92_rugby_subie Posted August 3, 2013 Share Posted August 3, 2013 After nearly 35K and VERY rough driving on a busted HG, Im gonna assume that Ned needs his new engine built... He is a 1986 GL Sedan, carb'd of course (weber 32/36 DGEV) The donor engine is out of a 91/92 Loyale SPFI... and I have a few questions... Although maybe not even noticeable, I heard there is a slight bump in HP with using the SPFI engine with the carb manifold (bumps compression) --- IS THIS TRUE? If it is, and that is what I do, do I use the SPFI heads as well? Will my intake bolt right on to the SPFI? Provided all this is going according to plan, I need to swap the better SPFI block onto the other SPFI motor and build them on the side (while Ned still gets me to/from work) and so Im going to be doing HG anyway... I heard with the Legacy/Impreza/Forester models, using a fel-pro gasket set isn't ideal with some seals, but Ill probably order individual parts rather than a whole set.... Now, if all that goes well, my majority of parts orders will be for a 91/92 Loyale (90-94)... but would the gaskets for the intake be the same? What might I experience being different, the headers should be the same Im hoping, but I do have the Y-pipe from the Loyale if need be (eventually going to have a better UEL made by Sube101) I bring this up because I missed 4th somehow and hit 2nd at a high rate of speed and buried the RPM gauge and when I got home my coolant reservoir had boiled over and there was coolant under the carb as well... Neds temp has been sitting higher than I would like to... and the clutch is almost gone... So I plan to hit all 1000s of EA82 bugs that I have with one gigantic... stone? engine? what have you kind-of thing. Link to comment Share on other sites More sharing options...
idosubaru Posted August 3, 2013 Share Posted August 3, 2013 Fel Pro headgaskets are great, no need to retorque them like Subaru and other gaskets. I prefer seals from Subaru or Beck Arnley, i've had EA82 Fel Pro crank seals not fit properly, but I've used them plenty of times with success before too so you'll see plenty of people with success stories. In general...i don't know about swapping...but Subaru intake and exhaust manifold gaskets are often much higher quality than aftermarkets. The aftermarket intake gaskets are particularly flimsy often times. Link to comment Share on other sites More sharing options...
NorthWet Posted August 3, 2013 Share Posted August 3, 2013 The significant difference is just in the pistons. Blocks and heads are essentially the same. There might be a difference as far as EGR, but I honestly can't remember at the moment. Link to comment Share on other sites More sharing options...
djellum Posted August 3, 2013 Share Posted August 3, 2013 manifolds cant affect compression, just heads and pistons. in this case pistons. id just basically rebuild the spfi motor and put the new clutch on it, then put the manifold,carb, and disty from Ned on it once its in. doubt it will ulitimately need it but I would start with 92 octane gas and work down to make sure you dont have knock issues with the higher compression (im assuming your running 20 deg timing). Im guessing that the bottom end on the spfi motor is fine, and the heads would be the gen 3 ones, so just work on it while driving the other motor as long as you can or need to. manifold carb and disty are a few hours of work so you can probably get the car back on the road in a day if you prep right. Link to comment Share on other sites More sharing options...
NorthWet Posted August 3, 2013 Share Posted August 3, 2013 The manifold Q was most likely about whether they would fit on the motor, not re: compression. (It will.) "Gen 3 head" is not relevant, as carb/SPFI heads are not prone to the exhaust divider cracking that MPFI "Gen 3" heads are supposed to help. (Unsubstantiated claim.) If you just swap complete cam carrier, you won't need to fuss with the distributor and trying to re-orient it. Link to comment Share on other sites More sharing options...
MR_Loyale Posted August 3, 2013 Share Posted August 3, 2013 (edited) The manifold Q was most likely about whether they would fit on the motor, not re: compression. (It will.) "Gen 3 head" is not relevant, as carb/SPFI heads are not prone to the exhaust divider cracking that MPFI "Gen 3" heads are supposed to help. (Unsubstantiated claim.) If you just swap complete cam carrier, you won't need to fuss with the distributor and trying to re-orient it. This is the first I had heard that the head crack issue was related mostly to MPFI. This fall I will be doing my SPFI (93 EA82) head gaskets. I hope you are right, it would be welcome news. I had also heard that you can just reuse the heads in most case the issue isn't critical. Is this true? Edited August 3, 2013 by MR_Loyale Link to comment Share on other sites More sharing options...
NorthWet Posted August 3, 2013 Share Posted August 3, 2013 Three are 2 main types of "head cracks". The severe one is a crack in the exhaust port divider in MPFI heads, and is usually restricted to turbo motors. The MPFI (dual-port for intakes) is a completely different casting than non-dual-port, and the exhaust divider does not exist as such in non-dual-port heads. The other commonly mentioned "crack" can happen to any head, as it is a crack in the combustion chamber between the intake and exhaust valve seats. Nearly every head will have these, but they are typically superficial and Subaru's TSB for this issue basically says to ignore them. Link to comment Share on other sites More sharing options...
92_rugby_subie Posted August 4, 2013 Author Share Posted August 4, 2013 I should have stated my questions better, but you guys have it correct. I want to make sure everything is going to fit with the options that I will have... I have an entire EA82 SPFI engine to work with, and I of course have the parts that are on my engine... Im just curious as to what I can build on the side with the spare motor to make sure that when the motor is built, theres very minimal down time (as I will be renting a car through my work at near $50 a day... Id rather start the engine swap process on a Saturday after work and hopefully have it done before I go to work again the following Tuesday. Is it possible to have an entire SPFI engine ready to go so I can just unbolt my carb-manifold and drop the new motor in? Will the SPFI disty work with the carb set-up? I also am not sure where Ill be fuel level wise on that day (as Im not planning on a specific time) so I could just use an octane booster right? and run premium for the first few weeks? Then plus and then regular? Also, wasn't thinking of re-building the SPFI motor, I have one longblock with a low compression in cylinder 4 shortblock, and then a known good shortblock so I was just going to swap it in, new gaskets and go... As rebuilding is an extra couple hundred bucks... and kind of a waste of time as Ill probably join the EJ crew next year when I buy my WRX Link to comment Share on other sites More sharing options...
92_rugby_subie Posted August 4, 2013 Author Share Posted August 4, 2013 Im guessing too, that I should be taking certain parts off the other motor to get machined and stuff first? As in the heads will need to be machined for the new gaskets, I should probably send the lifters in to Mizpah to get rebuilt so I don't have the tick of death on the new motor. What is a good oil? I just switched to synthetic blend 10W-40 and have had some decent results with it not leaking and burning as much, but until the oil warms up I do get a little bit of ticking... Link to comment Share on other sites More sharing options...
djellum Posted August 4, 2013 Share Posted August 4, 2013 I dont think the disty from the spfi wont work, normally a vacuum can disty and an cpu controlled one are different. from the sound of the parts you could do a complete motor minus dist and intake/carb, then swap it in. Jeszek hasa write up on engine oils, and theres a post floating around from General Disorder about doing head resurfacing at home with sand paper and a piece of glass. having the heads gone over is never a bad idea though. I dont know for sure if the extra compression would even matter, im just saying pay attention to it. you can go higher octane or lower timing advance, though I dont know if either is really needed. Link to comment Share on other sites More sharing options...
NorthWet Posted August 4, 2013 Share Posted August 4, 2013 I seldom run anything other than Regular-grade gasoline in my MPFI and SPFI cars. There should be little concern here. The distributors function differently, so you will need to keep your carb-distributor. As I typed in an earlier post, might be simplest to swap your distributor-side cam-carrier (w/distributor) between the 2 engines. Heads should get surfaced one way or the other: The head tends to get an indentation/groove from the HG's fire ring, and if this is not removed by surfacing your new HG will not seal properly. Machine-shop, GD's method, or even more primitive ways (I used a 7" sander/grinder on mine) should be done. Mitzpah's service sounds like a good idea, and resealing or replacing the oil pump should also be done. Don't forget to get the cam-carrier O-seals for the oil-passage: Very few places other than the dealer carry these. Intake and exhaust gaskets are often claimed to be better from the Dealer. Flywheel and clutch should be considered in advance. Oil sender unit might need to be swapped between engines, if one is just an idiot-light sender and the other is a gauge sender. Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now