EA82 spfi & IMPCO mixer carby on EA81

[jono]

Here is a pic of how it is ..err...stacking up with my tricky little adaptor, an IMPCO CA125 mixer, and A3-32 adaptor sitting atop an EA82 spfi inlet manifold I managed to prise from the grips of Scott in Bellingham , export downunder.....

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I have since added about 10mm of spacer tubing between the acc cable pull mount and manifold on longer bolts to improve the line of things

 

And this is how I finally on third attempt, managed the clearance issue there is between the EA81 edizzy vac can and the water pipe for the EA82 thermostat housing section of the  EA82 spfi inlet manifold.

 

First two goes involved tapping the hole of the drilled out pipe location to 1/8" NPT to nicely take 1/8" BSPT fittings, now blanked off with a brass plug.

 

Final method is a mounting tower for something topped with M6 thread. i reduced it in height with a 13mm drill bit and hacked off remainder, leaving nice thick solid boss to drill through, tap to NPT and screw in a M F 90 deg elbow in 1/8" BSPT, select 8mm barb for the hose, and viola! as they say. Takes the factory 7mm ID bypass hose without trimming, a little trim may be good.. Also real stoked to see a trial fit of the lower rad hose XX correction , it was a top hose from EA82 XX of an EA82 fit in reverse ? to the tight fit location of EA82 inlet thermostat housing to the EA81 MY radiator - looks impossible until it went on nicely

 

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The reasons for doing this in the first place was primarily to have a more sturdy setup than my silicone hose sleeve between the mixer and Mitsubishi efi throttle body adapted to an EA81 inlet manifold I had prior> Additionally hoping to employ the vac advance benefits , which are often unplugged on propane coversions anyway. I have run vac advance on same EA81 before without issues. The issue this time around may be that spfis did not run vac advance anyway :oops: We did not get the spfi option down here, just mpfi with or without hair dryer - and carbies. Now that I think about it, NA mpfi did not use vac advance except the early XT 4 Vortex.

 

I have a choice of three vacuum ports on the spfi throttle body to try anyway. May have port my own !

Edited January 4, 2014 by jono

[skishop69]

Nice! A few questions though to point some things out. Did you put EA82 SPFI pistons in the EA81 to bump up the compression? If not, you're going to loose about 15% of you're HP since propane has a lower BTU rating. Also, your idle quality will most likely be a bit lopey. Secondly, did you install new, hardened exhaust seats? Stainless exhaust valves? Propane conversions eat exhaust valve seats up if they're not hardened and can do the same to the valves over time if they're not stainless or at least high quality. I've built several V8 propane engines but never a 4 cyl though the basics are still the same. I believe Ivansimports here on the forum has one though. One other thing.... I'm not sure about the laws down under, but here you can't just throw a tank in it and drive. Huge legal and safety issues. Has to be a special, automotive use, mounted tank. Propane is great for off roading though, as it will run the same no matter how bumpy the terrain or how steep the incline! Stay away from deep water though! lol

[jono]

Thanks , just trying to match your XT halo repair quality.

 

Secret in the LPG is its alleged 109 RON octane rating compared to the 91, 95 and 98 wet petrol choices we have.

 

Many years ago when leaded petrol was compared to LPG mix of propane and butane, said to have only 80% the energy of petrol , volume for volume. So, to retain same -ish power - expect to use up to 20% more volume, and #1 it does, or did - until I added one leaning ring, fitted EA82 Y pipe and getting giggling great fuel economy and still driving well, powers well. This engine is only 30.000km since full flat top piston rebuild. Pistons were marked EA71, EA81

 

The valve seat issue - hardened seats for unleaded fuel and standard valves do the trick

 

 

This is Subie LPG #3 of mine , first being my first Brumby EA81 that has done 250 - 300,000km on LPG no worries on . This one already LPG, just improving on things. I suffered a power loss after conversion due to the 20/60 cam grind felt only when loaded up or towing 300kg trailer up hills but EA82 Y pipe fixed that. Power loss on this EA81 minimal, just not chirping tyres like it did on petrol. Snorts like nothin' else sounds like a weber I believe !

 

 

 

#2 is an EA82T, draw through   done about 80,000km so far and running up to 12 psi for brief moments and only in extreme hot days and mountain loads does it even tickle the knock sensor I monitor in dash.

 

As for legality - all complianced ! 80l useable tank in one - got a bit shakey at 720kms the other day, gauge still showing a little bit left, did not fill to work out economy but happy since it used 70 litre +/- 2 litres for 540km for ten years !

71 litre useable in the other ute, think sdan turbo EA82 has 72 litre capacity

Edited December 22, 2013 by jono

[skishop69]

Thanks! That first halo repair was a pain. Getting geared back up to drop in my EJ22 NA engine with the turbo added in. That's cool how well your LPG seems to work out. I always bumped the compression up to 9.5:1 or higher and reground the cam to even gain some HP. Never considered LPG on a Subie though just because I'm a power whore. lol

[silverback]

Did you change the timing advance curve of the distributor?

[jono]

on this one - no as I could not source the correct limiter to do as a spare, in order to retain original in case goes back to petrol.

My other EA81 - brazed up the max ends of the slots, advanced initial timing to 14 ? and got just another 14 so a max of 28 total as suggested by gas dudes (and likely referring to 6's and V8's when they did so)

 

My EA82T just gives it max advance until knock control cuts in - usually only under load on very hot days and hauls

 

It is now pretty much completed ...with all the gaskets in place adding a bit to its height, still clears the underside of the bonnet better than its last set up. It also has room to add PCV hose to the top of the air filter casing.

 

Need to wait a few weeks before it gets on the road to test. Not going to be the best comparison as it will be three months between drivng it with std EA81 intake and the wider insides of the EA82 spfi inlet manifold

Edited December 28, 2013 by jono