FJ1600 Question

[Yella7]

Jeszek 

thanks for the tip, I will do as you suggest and write to JTH.  We have nothing to loose

There is a company called "Japan Treasure Hunt" which brings rare vintage Japanese car parts, to America and other areas, they do an intermediation between the english spoken people, and the Japanese people, as they are in Japan; I believe that they could help both of you, to research and find the needed documentation, in Japan

 

Pete,

Thanks for the offer of spreadsheet information. I also have some information on the EA71 motor if you need that.

I too found difficulties posting pictures on this website so I'll send you a PM with more information on my car.  Meanwhile, the tyres I run at the moment are  180 X 550 x 13" slicks but really, they are too wide. 165 X 13 would be better. Ground clearance is around 60mm.  

 

Keep in touch,

Les

[Loyale 2.7 Turbo]

Jeszek 

thanks for the tip, I will do as you suggest and write to JTH.  We have nothing to loose  ...

 

Let us know the results, please  Good Luck!

 

... I too found difficulties posting pictures on this website so I'll send you a PM with more ...

 

As we Love photos here, I kindly suggest you to follow the steps written here,

 

to share photos on your posts:

 

~► http://www.ultimatesubaru.org/forum/topic/152891-recurrent-question-how-to-share-photos-on-your-posts/

 

Kind Regards.

[Astro12]

Hi All,

 

After doing some more research on my car, it turns out that
this car was manufactured by a company called Oscar, not Tokyo R&D as I had
previously thought. The car is an Oscar SK94 Bullet. Dead giveaway is the
billet aluminium pieces on each upright with OSCAR machined into them.

Have a few updates since my last post. I have the fiberglass
bodywork mostly complete but still some work to go. The original bodywork
needed some freehand blending which was helped by the use of polyurethane foam blocks
and some flat fiberglass sheet which I laminated. When finished to a final
shape this was glassed over and the foam was removed from the inside and
glassed on the inside. I could have left the foam in place but polyurethane
foam creates a cyanide gas when burnt. Not that I intend burning the thing, but
you never know.

The side pod bottom edge was raised by 10mm to allow more
support around the dzus fastener holes as the old ones were very close to the
edge and cracked easily. Exhaust outlet flanges were fitted to the undertray
and will be riveted on. New mounts have been made for the nose hatch which
allows access to the shocks and pedal assemblies.

An air box was fabricated in fiberglass, incorporating a flat panel filter to feed
the two Hitachi carbs, as originally they were fitted with tall ram tubes and
only a stainless steel mesh covering them to keep out the small rocks and
insects. As I intend running this car at some less than ideal venues, I figured
a filtered engine intake would be the way to go. The mould for this air box came
from the local dollar shop in the form of a rectangular plastic tub. I plan to
incorporate a couple of shorter ram tubes inside of the air box under the
filter. Air inlets will be cut into the front and top of the air box when I
finally have it bolted down.

The original head rest was sectioned and raised in height
and blended with the surrounding bodywork and air box.

When I have finalised the engine related bodywork, the
engine will be removed hopefully for the final time and rebuilt to ensure
reliability.

That’s about all I have for the moment so I’ll post some
pics of my progress.
 

Astro.

Edited November 8, 2016 by Astro12

[Astro12]

Hi All, I have been busily working away at the bodywork for the car and now almost complete. Some minor things need fixing but I thought it was time to turn my attention to the motor for this project.

To make the motor stable on the workbench I made some simple brackets which bolt to the bellhousing. Before dismantalling the engine I wanted to check a few things, like cam timing and CC's at TDC so at least I had a baseline with which to work. I made an adaptor to attach a degree wheel and a plate to secure a dial indicator on. The plate bolts on to the exhaust port of the head. Cam timing seemed a little different to factory with slightly more inlet duration 274 and less exhaust duration 251 than stock, which is 268 for both. Valve lift seemed very low with .339 Inlet and .332 Exhaust.

Cam timing figures were.

In Open 19 BTDC

In Close 75 ABDC

Ex Open 60 BBDC

Ex Close 11 ATDC

I've found a local cam grinder who has some different profiles for these engines, so maybe a new one is on cards.

Cylinder volumes at TDC Varied a little bit but this could have been due to some leakage. I will check again at dummy assembly stage.

#1 44cc = 10.1:1

#2 37cc = 11.8:1

#3 38cc = 11.6:1

#4 38cc = 11.6:1

With a bore size at 92.5 this would translate to the above compression ratios. I might have to run some high octane and be careful with ignition timing.

The pistons protrude the engine block by an unknown amount as I forgot to measure this before pulling it apart.

The heads have also been machined so that the combustion chamber protrudes into the cylinder. It's no wonder the pistons have been kissing the cylinder heads. Some remedial work necessary here.

One of the reasons I am pulling the engine apart is that the engine had been exhausting oil from #2 cylinder as evidenced by oily spark plug and exhaust port.

The cause of this was #2 piston skirt was cracked from the oil return groove to halfway down the skirt, and the oil ring expander had broken.

Makes me glad I decided to take engine apart.

Hopefully I can find a set of .75 pistons as a couple of bores are a bit pitted. Engine parts for EA71's over here are getting real hard to find.

Anyway that's about all I have for now so I'll post a couple of pics.

 

[Astro12]

A bit of an update on my engine. After inspection of the
engine it was realized that there are some issues which need attention. The
left bank cylinder head has been ported by someone who was a little ambitious
with the grinder and have ground through both head stud holes either side of
the inlet port and in the exhaust port to the pushrod area.

 

The inlet manifold on that particular bank of the engine has
also been over-zealously ported and broke through to the bolt holes.

 

The rockers have also been taken to with a grinder, very
badly I might add, leaving sharp edges and stress risers everywhere. The
miniscule performance benefit which this process may have gained, has left the
rockers in an extremely fragile state. Considering the fact that I will be running
increased valve spring pressures, the risk of using them is too great.

 

All these problems led me to start considering alternative
engines. Before I pulled the engine apart, I had the perfect engine an EA 81T
but sold it to another member, thinking that it would not fit in the chassis. I
did not realise at that stage that the 81 would simply bolt in where my fat
case 71 had been. How I’m kicking myself now. So I have been looking into
replacements. I got hold of an EJ 22 Liberty, pulled the engine and box.
Unfortunately the EJ package is just too different to go ahead with. The
chassis is very closely moulded around the EA platform and a change to the EJ
would mean big changes to the rear of the chassis. I have just gone too far
with the existing one so I am in the process of procuring a Brumby for its EA
81.

 

I still want to rebuild the 71 as a spare, so I am in the
process of sleeving the head stud and manifold holes with aluminium tube and
welding the exhaust port. I will need to get some replacement rockers for this
engine. If anyone has a set they would be willing to sell, that would be great.

 

I have looked into adapting some roller rockers but I have
not yet come up with a final solution. Jesel have some nice rockers with the
correct offset but the body interferes with the head studs and they are too
long as they are designed for nascar engines. I have also drawn a design in CAD
which could work but needs some refinement. I have a cousin who has a big CNC
mill, so I could potentially make my own but I just want to get this thing on
the track.

 

That’s about all I have for now so I’ll post some photos of
the carnage.

I've included photos of the cylinder head face which has been machined so that the combustion chamber protrudes down into the cylinder by .020" or .5mm. Also I've included a photo of the Naca duct which I moulded, to be glassed into the undertray to cool the exhaust and help the hot air get away from the radiators.

​
 

 

 

 

[pontoontodd]

That's quite a machining job on the heads, never seen that done before.  Is there enough piston to head and valve clearance?  Rough rule of thumb is 1mm piston to head cold, at least make sure it will turn over without the head gasket in between.  Probably want more if the engine is stressed.

[Astro12]

That's quite a machining job on the heads, never seen that done before.  Is there enough piston to head and valve clearance?  Rough rule of thumb is 1mm piston to head cold, at least make sure it will turn over without the head gasket in between.  Probably want more if the engine is stressed.

Apparently this was the done thing with engines in these cars. I've seen photos of another head from one of these cars with the same modification. It's just a shame that they forgot or just didn't know about basic engine building. The pistons in my engine have been kissing the cylinder heads. In my rough estimation I figure they assembled the engine with 0.020" piston to head clearance. I will probably be machining the heads flat, that alone will give me 0.040". I have been looking into pistons and have found that EA 82 pistons have a slightly lower compression height. Which ever way I go I will unfortunately be losing compression, but I'll try to retain as much as I can as my bigger cam will need it.

[Astro12]

I’ve been busy working on engine solutions. I managed to get
hold of an EA 81 out of a Brumby which was getting an EJ transplant. Thanks
Lewis.

So after I pulled all the unnecessary equipment off the
engine, I decided to install it to the car before I rebuild it, so that I could
sort out any issues prior to rebuilding it. I’m glad I did as there were some
issues to deal with. The engine bolted to the FWD single range 5spd with no
problems. That was the only thing which was a bolt on. The 81 has a smaller
spigot on the crank for the flywheel but a larger bolt PCD than the 71 flywheel
which is a bit of a bummer as the flywheel I have for the 71 has been
drastically lightened. This just means that I will have to lighten the 81
flywheel and keep the flywheel/clutch assemblies with the relevant motor, not
such a bad thing as they’ll be balanced as an assembly anyway.

The next thing I realized was that the tapped bolt holes
which my engine mounts bolt to are 5mm wider per side as well as 5mm lower.
This may not be a problem in a production car as the rubber mounts would
probably accommodate this comfortably, but in my car the mounts are rigid and
any offset needs to be dealt with. The way I dealt with this was to make new
engine mounts. That was all fine and dandy until I realized that the new engine
mounts would foul on the gearshift linkage. Luckily I was able to slightly
modify one of the mount to clear the linkage. There is some very slight
differences in the top bellhousing mount holes which just required that I
machine new spacers which now need to be engine specific.

The major difference is that the 81 deck height is roughly
1” wider than the 71 which means that my twin Hitachi carb manifold will not
fit, and I’m not about to cut this up to suit.

So I could run a single Hitachi on the standard manifold,
after lots of excess manifold protrusions are cut off and the thermostat
housing relocated.

I could make a manifold from scratch to suit the twin
Hitachi’s, but I figure if I’m going to make one I should make it suit a better
carb. I think an IDF Weber would be a good thing so I’m in the process of
buying one of those and I’ve modelled the manifold in CAD, to be fabricated
from aluminium. I will not have the coolant passage running under the inlet
tract, this will be plumbed directly to the thermostat housing which will also
have to be fabricated as a remote unit.

I considered fuel injection as an option, which would make
for a really easy and desirable inlet configuration, but the system would bring
with it, unwanted baggage. The car does not use an alternator as there is not
enough room for one, so running an injection system that is reliant on battery
power would be a bit of a drain on the system. 
Apart from the above, injection would also add unwanted complication in
terms of wiring, tuning. At this stage I just need something simple and
reliable. I may consider injection down the track, but for now a carb will have
to do.

So I’ve made all these changes to suit the new engine, apart
from the inlet manifold, so these will be squirrelled away for use when I want,
or need to use the 81. I figure it makes sense to make the car suit the 81 as
they are a lot more available than the 71’s. First up I’ll be rebuilding the
old 71 and I’ve sleeved the cylinder head and inlet manifold where they were
excessively ported. I will be using the 81’s rocker assembly on the 71 until I
can source a replacement set.

So I haven’t been idle, I’m doing something every day, but
life and work get in the way of building racecars.

 

Astro.

 

 

[Astro12]

 

Hi All,

 

I’m getting really close to paint for the chassis and body
panels now. It will be great to see it in all its designed colours finally.
Then the most exciting bit, the final assembly.

 

I still haven’t rebuilt a motor for the car yet, but I’ve
had some development on that front. I was able to purchase some replacement EA
71 cylinder heads as the ones I had weren’t able to be saved. They came with
rocker assemblies and rocker covers.

 

The heads have been reconditioned but have been sitting for
a while so they will come apart for a look-see. This means that I will now be fitting
the ‘71 with twin carbs first up, and have the ’81 as a spare. I have made an
inlet manifold for the ’81 to suit a 40mm IDF Weber. I’m not entirely happy
with it, but it will work and I may end up making another one for the ’71. I
made the manifold from steel 1/5/8 mandrel bends and steel plates as the
aluminium bends were deemed too expensive at this stage of the build. I decided
to make the manifold in three parts because I am not sure of the final deck
height I will end up with so at least I will have some adjustability in this
department. This meant that the carb could potentially rotate so I made an
adjustable brace which mounts to the front of the engine. I made some coolant
outlet ports which will be welded to the inlet flange plates to take coolant
from the heads to the remote thermostat housing.

 

 Regulations require
the fitment of a fuel tank vent valve which shuts in the event of a rollover so
I purchased one online, not realizing that this valve is designed to be mounted
in the top of the fuel tank and an extended vent line attached to the valve. I
did not wish to cut an additional hole in the tank, I wanted an inline valve which
could be mounted up high so I came up with a design which uses commonly
available brass BSP fittings and works just as well. I wanted one also for the
coolant overflow tank so I made a bracket to mount the two valves to the
chassis tubing.

 

I’ve added some brackets to the radiators for securely mounting
them in the rad ducts with three M6 bolts. They were previously held in by zip
ties through the core. Bleed nipples have been added to the top of the
radiators to bleed any air bubbles back to the header tank. The radiators will
be gently soda blasted before being painted in heatproof aluminium paint. Radiator
inlet ducts have been radiused and smoothed.

 

I’m in the process of making some new suspension pushrods
which are longer than the originals as the car came with about 25mm of ground
clearance and the new ones should give it about 75mm. You can always come down.
I purchased the chrome moly steel from a company in Sydney which I have dealt
with previously for my roll cage tubing. Racetech steel are a pleasure to deal
with and have ample stocks of the right stuff for building race cars.

 

That’s about all I have as far as progress is concerned.

 

I’ve included a photo of an exhaust valve from a ships
engine which I have in my workshop which was given to me by a friend. The valve
measures 1m tall. Not sure of the engine it came from but a cool piece of
engineering.

 

 

 

[Astro12]

 

Finally some progress!!

 

It’s been a long time since I posted, just because I have
not had any new or exciting developments to report, just lots of
sanding/filling, followed by more sanding/filling.

 

I just remembered, I have
been doing other stuff like making foam cutting implements, cutting foam core
wings and moulding wing mounts. I have yet to laminate the wing cores in carbon,
but these can be finished after the car is done. New longer pushrods have been
made as well as anti-intrusion tubes welded into the front lower a-arms. All
suspension parts have been sandblasted and painted. I’ve made a body panel
stand to hang the panels on when they are off the car. Packed mufflers with
stainless wool. Rebuilt carbies.

 

Today, however, I have just finished painting the chassis
after sending it off for sandblasting and receiving it back four weeks later.
Two weeks overdue. I have used a colour called Blue Grey and I am pretty happy
with the result.

 

I had planned to have someone paint the fiberglass bodywork,
but money became a bit short just before Christmas, so I have decided to paint
it myself. I had a colour mixed to match the original Blue.

 

Because I like my neighbours, and I do not wish to paint my
other cars and my house with my efforts at spray painting, I decided that I
would need a paint booth in which to paint my parts. Luckily for me, whilst at
a recent garage sale I picked up a used 6 x 3 meter gazebo which had been used
for a wedding reception for $10. The seller assured me that all of the parts
were there. Including walls with windows. The sellers’ wife assured me that it
looked beautiful when assembled with fairy lights for decoration. I didn’t have
the heart to tell her that it was going to be used as a spray booth.

 

The spray booth was assembled and taped at the joins, a
floor consisting of pond liner was added and taped to the walls. A 500mm floor
fan was used to extract the fumes and a filter of dressmakers wadding was used
as a filter at one end. The fan worked quite well with no noticeable fog in the
booth while painting.

 

After undercoating the body panels this afternoon, it seems
that I have plenty more sanding and filling to do before I can put a top coat
on, but at least I can see where the problems are now.

 

So for now, I’ll post some pics of progress.

 

 

 

[Astro12]

Progress is coming along now,

Today I started the topcoat process by painting the undersides and insides of all the panels. Next is prepping the outsides of all the panels for their final coat. It's great seeing the final colour after all this time.

[Astro12]

Finally finished the painting of the body panels After a couple of days of prep to get the panels ready for the topcoat, I have all of the panels painted. Now for the best bit, engine and reassembly. I have started the reassembly process but I will have to wait until I get the engine back in to complete some things. The worst bit is I have to go back to work next week but the engine rebuild will also be starting next week. I'll try to remember to take photos of the engine process.

Here are some photos of the completed panels.

 

[pontoontodd]

How much longer do you think it will be until you drive it?

 

Looking good, love your paint booth!

[Astro12]

Hi Guys, started pulling apart my reconditioned replacement heads for the 71 today. Looks like I have some work ahead of me! The heads have been reconditioned quite well but are stock as a rock. There are some very restrictive looking bits in the ports so they'll be in for a bit of porting. At least I have examples of how far I can't go with the original heads. The valves in the original head are also bigger but have a different collet groove and retainers which would not allow the valves to rotate so I hope I can get new bigger valves with the square collet groove to suit the new collets and retainers.

Is any one familiar with these different collet grooves ie. which models have which groove? The original retainers look like the have been machined a lot to make them lighter so they may not even be Subaru, but the original valves with the round collet groove are definitely genuine Subaru. I would have reco'ed heaps of EA heads in my day but that was 20 years ago and I wouldn't have taken much notice which collet groove they had.

If I have time I may flow test the new and old heads for comparison and to help me choose a cam. Has any one had anything to do with the Sub4 cylinder heads for EA 81 from New Zealand? Are they still making them? I've tried to research them but seem to come up a bit short of information. I know Flygas makes a set of 81 replacement heads but I think the price might frighten me!

As for as when I'll drive it, who knows, at least a couple of months. If it's not time I'm short of, it's money. Oh well. At least it's going back together.

Astro

Edited February 5, 2018 by Astro12

[Astro12]

Hi All, engine progress is slow at the moment as I'm still waiting for parts, so I thought I'd share some photos of the chassis and body going back together. Heads have been ported but just need oversize valve seats cut when I get my new valves. I have done some initial comparative flow testing with the original heads and it appears that I'm not that far off the extensively ported head with my new ones with bigger valve seats to come.

I've been trying to complete everything that I can prior to needing the engine, but this is taking some time so I have been assembling some body panels which will have to come off again for the engine install. Shocks are rebuilt, springs powder coated, electrics are mostly complete, just need terminating at the engine, some engine related plumbing.

Through my research into engine parts for this engine, I've found that Mitsubishi 4G63 (8 valve) engine valves are almost a direct fit for the larger valves available for the EA engine and the conrods from the same engine are a match for big end size and gudgeon pin size, although they must be a longer rod as this engine has an 88mm stroke. Some further research needed. Just thought someone may be interested!

So for now I'll post some photos. 

[Subaru Scott]

Hey, nice little project you got there! Looks like you're making good progress. I'll bet that thing is fun as hell to drive.

 

I always wanted to build an EA71, just because I love the super-short stroke and wanted to see what kind of rpm I could get. 

 

But I was always broke back in the days I ran those... with kids... so it never happened.

 

That type car is the perfect platform to have for that engine. Enjoy!

[Astro12]

Finally got all of my engine parts today. No excuses now! I
was not able to get completely flat top pistons as I had hoped, it seems that
the only ones available now are EA 82’s with valve reliefs and a lower
compression height. Just means I’ll have to take some more off the block. Oh
well, I guess that’s the way it is when playing with older engines.

 

I’ve been assembling parts of the car which I can do without
needing the engine. Front end is all built, body is mostly done, just needs a
few more dzus fasteners and the mirrors mounting. I couldn’t help myself the
other day when the car almost became a roller, with the help of a trolley jack,
I rolled the car out onto the driveway and took some photos.

Astro

[pontoontodd]

 

Finally got all of my engine parts today. No excuses now! I

was not able to get completely flat top pistons as I had hoped, it seems that

the only ones available now are EA 82’s with valve reliefs and a lower

compression height. Just means I’ll have to take some more off the block. Oh

well, I guess that’s the way it is when playing with older engines.

 

 

I’ve been assembling parts of the car which I can do without

needing the engine. Front end is all built, body is mostly done, just needs a

few more dzus fasteners and the mirrors mounting. I couldn’t help myself the

other day when the car almost became a roller, with the help of a trolley jack,

I rolled the car out onto the driveway and took some photos.

 

 

Astro

 

Looking good, should be a blast when it's done!

 

Make sure you have enough piston to head clearance.  Guess I mentioned that before.

Edited May 29, 2018 by pontoontodd

[Astro12]

Hi All, finally I’ve had some progress engine-wise. The engine cases have been bored and honed and machined the valve seats for the oversize valves. Multiple angle valve seats and back cut valves. What appears to be small gouges and scratches in the seats, is actually remnants of Vaseline which I smeared on the seats to stop rust. I still need to do additional porting to open up the restriction point near the manifold faces, inlet and exhaust, where the casting for the head bolts is. I am hoping I can open this area up without breaking through as the original heads were. After this porting, the main restriction will be the cast twin carb manifold. There’s not much I can do about this, but I will have my fabbed IDF Weber manifold at the ready to substitute after I’ve run the engine in.

I checked the piston to valve clearance, and the valve cutouts in the pistons are just a wank, the valves have 0.350” travel at TDC without a head gasket. The valves will never get close enough to the pistons to need valve reliefs. The only thing that they do is reduce compression by 3cc.

The new pistons have a shorter compression height than the original ones so I’ll be machining the cases to have the pistons 0.010” above the deck face. The pistons are 0.014 – 0.022 below the deck face currently. I’m having a bit of a dilemma regarding head gaskets. I’ve purchased two Permaseal gasket sets, an older set and a newer set for the same engine, and the head gaskets are 0.020” thicker in the newer set. As I am trying to maximise my compression ratio this gasket inconsistency has the potential to become a big problem. At the moment I’ve based my calculations on using the thinner gasket leaving 0.042” for piston to head clearance. If I was to base my calculations on using the thicker gasket, and machined the deck accordingly, somewhere down the track if someone substituted the thinner gasket, the pistons would once again, hit the heads. I just don’t know what gaskets are going to be available in the future.

This brings me to my plea, for anyone in the USA who may be able to check on availability of Fel-Pro gaskets for this engine, and also for the EA 81 for me. I’ve tried here but no-one seems to be interested in suppling parts for these engines. I have both part numbers,

 EA 71 – P/N 21205 PT-1.

 EA 81- P/N 8818 PT.

 and a link which I’ll post here.

http://www.fme-cat.com/Application.aspx?year=1980&make=SUBARU&model=BRAT&cat=Engine&subcat=Gaskets and Sealing Systems&brand=Fel-Pro&engbase=1.6L 4Cyl H (1595)(-)&ga=Y&back=true

Also I have a part number for Total Seal gapless rings for these engines, which again, do not appear to be available here. Part No MX7565

So please, if anyone could confirm for me that these parts are available in the US or not, this would help me greatly.

I made a new crankshaft pulley as the old one had cracks in it. The pulley hub is machined from steel and the pulley which bolts to it is machined from aluminium.

The new water pump was only available with the small standard cast pulley so I removed this and fitted a the flange to which a larger diameter pulley was fitted to reduce the pumps rpm’s and limit cavitation at higher engine rpm.

The car is finally rolling on four wheels so I’ve included some photos of that as well……………  Astro

 

Edited August 4, 2018 by Astro12
Add Photo

[Astro12]

Hi Guys, my engine is progressing well now. I would like to thank a couple of USMB members, golucky66 and pontoontodd for your assistance and research in regard to head gaskets and piston rings, Thanks Heaps guys

I was able to get the Felpro gaskets from the US, but as they are 0.092” thick and compress to 0.088”, I now have to machine about 0.060” from the block faces to achieve a reasonable compression ratio. This will put the pistons at + 0.044” above the deck, still leaving 0.044” piston to head clearance. I still have to machine the heads to reduce the chamber volume from 40cc to 34cc to achieve 10:1. I’m guessing that this will take about 0.020” off the heads. I’ll be cc’ing the heads as they are being machined, so I may end up with a little more than 10:1 if I’m lucky, maybe?

I was able to purchase the rings through a local company who deals with Total Seal USA. Standard rings were available off the shelf, but unfortunately for me I needed +0.040”, so they had to be custom ground, making them more expensive. I bit the bullet and paid the man the money. They turned up about two weeks later, which I think is awesome service. They are now gapped for the cylinders. Now most of my hard fought combustion pressure will stay where is supposed to!

I’ve had several porting sessions now with the heads and some flow testing in between. Results are looking good with more flow throughout the valve lift range than the original heads the car was supplied with. I’m very surprised with these results as the original heads have had a lot of port work. Just goes to show that bigger is not always better. The new heads have an EGR port in one of the heads so I made an aluminium plug to blank this off.

Rotating and reciprocating components have all been balanced. I also resized the conrod B/E, just to be sure. The assembly had obviously been previously balanced, but was found to be about 6 grams out on the crank and about 10 grams on the flywheel. All is well with the balance now. It was hard to find a place to remove metal from a flywheel with so little available metal left.

That’s about all I have for the moment, with some more progress to follow shortly.

Astro.

[Astro12]

 

Hi Guys, almost finished porting the heads, with just some minor tidying up to do. I’ll machine the manifold faces when I’m finished porting. The ports look quite different now compared with how Subaru cast them. Throughout the porting process, I’ve tried to open up the cross-sectional area as much as possible without removing too much metal in areas where this would lose airspeed in the port. I’ve re-machined the rocker arm contact faces and reassembled the rocker assemblies.

[Astro12]

A couple more photos.

 

[Astro12]

Ok Subaru fans,

I’ve been having a bout of procrastination with regard to cam spec for my engine. I’ve actually had the original cam built up and ground to a spec which I now consider to be too large for my application, see attachments.

 To quote a famous engine builder, I endulged in the Stroker McGurk syndrome, ie. if some is good, than more must be better, and too much must be just right. So I now, have to take my lovely new cam back, to be ground back to something sensible. I hate do-overs, especially when it costs hundreds of dollars!

The cam spec may be ok if I had forged pistons and therefore could rev the engine over 6000rpm, but I just have to be realistic about what the engine is capable of, also the short nature of the circuits I am likely to drive on really don’t suit a much larger cam.

So I am considering something in the range of 230 degrees of duration at 0.050”, instead of 262 degrees.

The blocks have been decked 0.060” to achieve the pistons sticking out of the bore by 0.044 to compensate for the 0.088” thick Fel-Pro gaskets. That still leaves 0.044” for piston to head clearance pontoontodd. I would strongly advise against doing this as this makes the decks very thin above the liners. If I were to do this build again I would pay the extra money and have custom forged pistons made. The heads have been machined 0.071” to reduce their volume from 40cc to 30cc to achieve a 10.6:1 compression ratio.

I’ve attached some graphs of the old and new (too big) cam specs for you perusal.

So all going well I should have the engine together and in the car by January. I’ll post some pics and hopefully vids of startup.

[pontoontodd]

On 12/5/2018 at 1:17 AM, Astro12 said:

Ok Subaru fans,

 

I’ve been having a bout of procrastination with regard to cam spec for my engine. I’ve actually had the original cam built up and ground to a spec which I now consider to be too large for my application, see attachments.

 

 To quote a famous engine builder, I endulged in the Stroker McGurk syndrome, ie. if some is good, than more must be better, and too much must be just right. So I now, have to take my lovely new cam back, to be ground back to something sensible. I hate do-overs, especially when it costs hundreds of dollars!

 

The cam spec may be ok if I had forged pistons and therefore could rev the engine over 6000rpm, but I just have to be realistic about what the engine is capable of, also the short nature of the circuits I am likely to drive on really don’t suit a much larger cam.

 

So I am considering something in the range of 230 degrees of duration at 0.050”, instead of 262 degrees.

 

The blocks have been decked 0.060” to achieve the pistons sticking out of the bore by 0.044 to compensate for the 0.088” thick Fel-Pro gaskets. That still leaves 0.044” for piston to head clearance pontoontodd. I would strongly advise against doing this as this makes the decks very thin above the liners. If I were to do this build again I would pay the extra money and have custom forged pistons made. The heads have been machined 0.071” to reduce their volume from 40cc to 30cc to achieve a 10.6:1 compression ratio.

 

I’ve attached some graphs of the old and new (too big) cam specs for you perusal.

 

So all going well I should have the engine together and in the car by January. I’ll post some pics and hopefully vids of startup.

 

Normally I would agree 100% but this is a race car, right?  Are you planning on running it hard or just cruising around the track?  If the transmission is geared properly you should be able to keep the RPM up in even the slowest corner.  Are there any experts on this engine you can consult for what these two different cam profiles would do for your engine?  It seems like a big change, I would think 240-250 might be best.  Do you have adjustable cam gears?  Unfortunately you can't adjust intake relative to exhaust, it looks like your lobe separation angle (intake to exhaust) is similar on both cams, you might want to change that too (less for lower RPM use I think).  Also I don't know if it affects the grinding cost but on most pushrod engines I'm aware of you want about ten degrees more exhaust than intake duration (so maybe 240 intake / 250 exhaust).  Are you planning on running it on an engine or wheel dyno to tune it?  I can tell you cam timing will make a huge difference on how much power you make and at what RPM it peaks, easily +/- 10% with say 20 degrees change.  How do the cast pistons limit your RPM?  I'm familiar with rod and bearing failure with excessive RPM, are the forged pistons just that much lighter that it's easier on the rods?  Just hoping you get the most out of this build, I think it will be awesome when finished.  Take this all with a huge grain of salt, I don't know anything about EA engines and this is all very engine dependent.  For instance if your ports flow very well I think you can get away with less duration.

[Astro12]

Hi pontoontodd, this car will be used for very short and tight hillclimb courses where bottom end power is of more use than top end power. As for the gearing, well I just have to put up with whatever ratios Subaru put into the Leone FWD car as I'm sure there are no aftermarket gearing options. No adjustable cam gear. Lobe separation on old cam was 100 degrees and new one was 114, new revised cam will have 109. Might put it on rolling road if I can't sort it out on track. The RPM limit is a self imposed one, as I have found out through research that the cast pistons tend to crack the skirt from the oil scupper slots when revved over 6000 RPM.Two of the pistons I pulled out of my engine had these cracks. I'm pretty sure my engine saw over 6000 RPM. see tach photo. I doubt that the engine would have made good horsepower at these revs with the small cam it had. Forged pistons would likely be heavier but much stronger. I would also specify oil scupper holes, rather than a full skirt width slot as in the cast pistons. EA cylinder heads are very poor as far as port shape and flow, I managed to port my heads to flow more than the original ones, but they are still way off what is needed for big horsepower. All I can hope for is a really fat torque curve.

Astro