EA81 Dyno Tune results

[tweety]

Yesterday my trike got its final Dyno tune. But a recap first.

 

A few years ago I ditched the then 1916cc VE engine that came supplied on my Oz Panther trike. I ordered it with the VW 3 speed automatic from a 1971 model. After several major issues with the VW engine I replaced it with the EA81. Many people say use the EJ seies engines. In hindsight, due to it being an auto I had good reason to but there were several other reasons for going EA.

 

- tilt test is required in Oz. Means extra weight rear of the standard centre of gravity causes issues with engineering.

 

 

Tike reached 62 degrees before it tended to tilt. This was within spec.

 

- Room,  the ea81 is less width than the VW so fitted easily. The engine bay needed to house the total exhaust system.

 

- Chassis strength. The trike has alloy monocogue frame. It ability to take the extra weight is questionable.

 

Thats the EJ question over and dusted.

 

Originally I had the weber 32/36 carbie. No anti pollution stuff is required on trikes in Oz so off it all came. I noticed the 32/36 was frustrating me combined with the auto.  Then we purchased a small trailer. It weighed 1300lbs so I needed extra power. I mounted a SC12 Toyota supercharger with delorto carbie. I got the power....about 100+hp but I had no shares in Australia's vast oil ore deposits to afford to run it. 14 mpg.

 

 

Then next step was SPFI. I had several issues after install. The MAF was faulty (thankyou Rockauto for supplying a Nissan one instead of an eA82 one) then throttle sensors (thankyou USMB member Naru for chasing those up for me) and the system really needed someone with more knowledge than I.

 

We sold our trailer and had little need for huge HP. We decided to fully recondition the ea81.

I retained the SPFI manifold. Purchased a 38/38 weber synchronic carb. I had made a custom adapter.

 

 

I had the valve covers chromed, painted up the custome exhaust and had seals in the auto renewed.

 

 

 

 

The engine was balanced, 9.5:1 CR, bored to 1820cc (1mm larger pistons) and a ground cam good torque for low revs.

 

Two weeks ago we did our first dyno tune. Dont forget the engine pushes a power draining automatic transmission using up to 23hp. Yesterday with the correct jetting we achieved 53hp at the wheels and a huge 6% more torque as can be seen by the graphs.

 

There was one issue with this size carbie. It is usually more suitable for a engine 2500cc or more. With an engine as small as the ea81 you really need smaller fuel squirters. But the ones on this carb were the smallest available. The result was riding slowly around corners sometimes give a short hiccup. The engine is being flooded. The was compensation with using smaller idle jets that fixed the problem almost entirely.

 

 

 

 

 

We also got the best timing right. Way back when the engine had an adapter plate bolted up, the timing marks disappeared as they were on the flywheel that was discarded. The dyno tuner ran the engine to its peek performance then the timing was found to be 12 degrees. I made up a marker to point to that point. No more guess work.

 

So, how does it run?  Very smoothly with the least amount of flat spots. Cant detect them now. Great pick up. Easily raises the front wheel about 6-8 inches off the ground in a controllable manner on take off. Much much better torque felt.

 

We spent a total of 6 hours on tuning. I would recommend to owners of new rebuilt engines to get this tuning done regardless of cost. Nothing helps more than a dyno with a graph screen. Cheers  Tony

 

 

Edited May 5, 2015 by tweety

[two85s]

That is amazing!!  Excellent and beautiful work.  Thanks for posting your work and results.  Very nicely done.  All the best to you, Aaron

[zombieblues]

Beautiful trike!

[Loyale 2.7 Turbo]

The Trike is Awesome, and also your EA81 looks Awesome.

 

Very kindly, Let me ask you: ~ 53.2 Hp on the Wheels, 

 

Means how much Total Hp output from your Modified EA81?

 

Kind Regards.

[tweety]

Thankyou all.

 

I havent got hp at the crank amount. I told the dyno operator that the stock ea81 is rated at 73hp and so 53 at the wheels "would that mean at the crank this engine is more than 73hp" his response- "way over".  But I'm wise enough to know it wouldnt be that much based on my experience with previous mods. eg

 

4 years ago  I had this engine worn and stock with no anti pollution stuff and a 32/36 carb. From standstill the front wheel wouldnt lift off the ground at all. Then there was the supercharged version that produced 100hp + (i.e. on the dyno it hit 100hp then a leak in the custom manifold occured so that was the end of that days work). At standstill the front wheel could rise 18 inches and at 25mph when changing from 1st to 2nd on the auto would rise again about 3-4 inches. The engine however was not tuneable at different rev ranges. = very inefficient with raw fuel exiting at times. By the time SPFI was fitted I believe the supercharger had done internal damage so no running result with the SPFI could be taken seriously. In terms of power from standstill this engine now rebuilt with this carbie and cam (see cam specs below) is somewhere in between the 32/36 and the supercharged version. My guess....maybe 80-85hp at the flywheel.

 

 

More importantly is torque output.  The engine builder was asked to rebuild this engine with highest torque possible with lowest revs. Afew reasons for this. 1/ am an older driver (59) and had my days of high revving Lotus's etc and wanted this trike to be a comfortable quiet cruising machine. 2/ the auto trans dictates performance would be more desirable to have torque at low revs 3/ A long lasting engine is wanted with the least fiddling. The rebuild specs are below

 

 

Rgardles sof being rebuilt for a torque engine it is free revving more than I thought it would be.  The max speed in gears for around 5000 revs are around 25,108 and 80. Max speed restricted by the parachute effect of the roof that begins to take effect around 75mph onwards. On the dyno it freely went to 100mph with no wind  lol.  There are more informative members here than I to make sense of all these dyno figures. But I suppose the smile on my face tells me of how happy I am. For some of these decisions were a gamble. I've read up on and used the 32/36 carbie. It is a carbie as they correctly claim "is about 3mpg more economical than the 38/38". But I found using the 32/36 in conjunction with the auto trans wasnt a good match as just when the second throat would open the trans would change up. You had to operate the auto as a manual to get best response and that defeats the reason for an auto transmission. My only other comment after all these mods is that I believe a Holley single barrell carbie or similar would do just as good a job as this 38/38 has and maybe easier to tune. My dyno man told me he had all the jets and squirters for the Holley carbies.

 

As previously stated the eJ option might have been worth my effort considering how much power is lost with the auto trans. With a manual gearbox this little ea engine would have been a delight in this trike weighing 660 kgms. With the auto when climbing some hills that loss of power is noticeable when a 3rd manual gear would be ideal when the auto is screaming in 2nd. But I must say that with the increase in power and torque now, climbing the same hills often sees this engine hold its speed in top gears much better than it did.

 

I will stick to the auto trans. Most trikes here in Oz are manuals. I dont like taking my left hand from the bars to change all the time. There is no feeling better than cruising the winding beach roads in the summer with the auto doing its thing. Below is some pics of the trike on the "Great ocean road Victoria". The road was built by post WW2 soldiers upon their return to their country. Its 2 hours of bliss. I once had a Porsche 911 behind me. Road signs before bends often read 35mph (70 kph) just right for the trikes 2nd gear kickdown. These bends were taken at 65mph though with such grip the Porsche was left behind every time.   Mind you when the straight road came I saw his tail lights.....Think that guy regretted paying 4 times the price for half the fun.

 

 

 

 

 

[Loyale 2.7 Turbo]

One word: Awesome!

 

Yes, at ~ 9.48 Compression ratio, that EA81 must be in the Neighbourhood of 100 Hp at the Flywheel, and I Agree with you, many people spend their money in Expensive cruisers that doesnt payback a single drop of Fun.

 

Thank you for sharing this information and Photos.

 

Kind Regards.

[coxy]

If you could get the Air Fuel graph in the last chart sloping the other way and finishing at the same AF ratio at top end it would be perfect and probably get another 5 MPG on cruising.

 

What it wants is about 14.2 to 14.4 at cruise and around 13.2 at full throttle, Did he do any part throttle runs as well as those figures at at full load and it is a bit rich down low and in the Mid range (We Have a Dyno at Work)

 

Part throttle you would not want to go any leaner than about 14.5 or it would lose power and probably miss too much because of the manifold length on an EA engine, The theoretical perfect AF ratio otherwise known as Stochiometric is 14.7, Meaning 14.7 LBS of Air to One Pound of Fuel.

With fancy modern Injection and Ignition systems they can run acceptable much leaner than that but they lose a lot of power, The XR6 for instance has a cruise mixture ex factory of about 18>1 and boy do they really pick up power making them a bit more normal richness wise.

 

Problem with making things lean to pass emissions laws and looking for Economy is that often richening them up makes better power and torque and gets better fuel consumption but emissions go ballistic so we have the false economy forced on us by Bureaucrats whereby they see the emissions figures they want but the vehicle uses more fuel so for distance travelled a richer Illegal spec engine can in fact put out less emissions than a legal spec engine because it does not burn as much fuel for the distance travelled.

 

A good example of that is that a Ford Territory actually gets about the same fuel mileage as a 1971 GTHO, Hullo what with the cost of fuel and a territory supposedly being a Family car why does it do little better than a Seventies Muscle car with a 351 4V Clevland when it has a supposedly  efficient injected whizbang multi valve twin cam inline Six with variable cam timing??

[naru]

coxy, on 06 May 2015 - 06:09, said:

 

 

A good example of that is that a Ford Territory actually gets about the same fuel mileage as a 1971 GTHO, Hullo what with the cost of fuel and a territory supposedly being a Family car why does it do little better than a Seventies Muscle car with a 351 4V Clevland when it has a supposedly  efficient injected whizbang multi valve twin cam inline Six with variable cam timing??

 

That is not a good example at all.

Surely weight is a big factor.

2915 lbs. for a 4 speed GTHO and 4508 for a Ford Territory.

That is 55% more.

[tweety]

mmmm, dynoes are a science. Been reading up a lot tonight and got a headache now ahha.

 

Some automatic cars compared to manual can lose up to 40% but there is a 25% "rule" being the norm to go by.

[carfreak85]

I gotta ask, why did you use road speed on the x-axis instead of engine speed?

[tweety]

Hi carfreak

 

Perhaps the answer to that question is- I have no idea. I'm limited to my knowledge of what the dyno operator does and dynoes in general.

 

I've just let it be in his hands and he did the graphs at the end.  

 

My "expertise" is in tinkering and design, ideas and testing them. Hence since owning this trike I've designed and had made the roof, installed  the ea81 in place of the VW using an adapter plate, made my own manifolds up for the install of a supercharger, installed spfi with reasonable success, designed the exhaust etc. but when it comes to tuning, carbie workings, ECU's, etc I'm at a loss.......oh, and I'm good with the ladies     Tony

[Uberoo]

So what is the point of the "tilt test?

[MR_Loyale]

I think it is to see at what angle the trike will flip backwards from the counter force of the torque driving the wheels. At steeper angles, the gravity vector that opposes the torque lessens until at some angle the torque overcomes the gravity component opposing and the trike flips backwards.    That or I am just full of crap. lol

[tweety]

yeh guys, all to do with safety, if too much weight at the rear. Imagine if there was no tilt test. A large V8 on the back of a home built trike. snap the throttle and you're on your head.

 

Likely not done in north America. We aussies have a big brother here, several in fact. Having said that the engine protection bar is designed to prevent your trike flipping backwards anyway..

[Uberoo]

looking on youtube Ive seen some v8 trikes doing wheelies,the problem is with a v8 is that the engine has to sit so far rearward of the tires that even if they wanted it to flip the engine will hit the ground long before the trike will tip.Which makes the engine an effective abit expensive wheelie bar.Most of them are rocking some sort of steel bash bar which limit the angle even more.Heck, even yours would have hit the engine/exhaust on the ground long before it would tip,the only reason it got up so high in the first place was because the back tires were on those ramps.In the interest of safety your government made a rule that typically physics wont allow to happen in the first place.Unless someone makes a trike with the engine sitting vertically over the transmission,which is vertical over the tires,a trike will not flip over without some serious help.

 

I could see a "lean" test where the bike is angled over sideways to see how far it would lean before tipping being valid but not the tilt test.