Ace Of Spades 51 Report post Posted October 1, 2012 I have a FL e30 325i with the piston rings starting to go and I have got a spare m20 b25 but its PFL... Is there any differences between the PFL and the FL m20s? Or do they just swap right over? If so what are they? Any info would be awesome as im on break for 2 weeks and would love to get this done asap! Cheers Sam Quote Share this post Link to post Share on other sites
_Matt_ 42 Report post Posted October 1, 2012 (edited) same engine, wait for an experts answer though Edited October 1, 2012 by _Matt_ Quote Share this post Link to post Share on other sites
Andre3000 55 Report post Posted October 1, 2012 You'll probably have to swap the entire loom and ecu aswell. I'm pretty sure the crank angle sensor is located differently, but there may also be another way around this. Have you thought of mixing & matching? I hear you can get more power using the PFL head on a FL short block, but don't quote me on this. Have a search on e30tech.com/forums or r3vlimited.com, they both have a wealth of information. Quote Share this post Link to post Share on other sites
BM WORLD 1286 Report post Posted October 1, 2012 just use the bare engine block and manifolds. use all your original electrics that are in the car etc. i think the early engine may have higher compression pistons?? what happened to the m50b25 conversion?? Quote Share this post Link to post Share on other sites
Ace Of Spades 51 Report post Posted October 1, 2012 Still haven't sold the engines yet so the bank balance is quite empty Ok, the other engine is striped appart from the manifold, head and block. So basically the fl loom will attach to all the pfl plugs on the engine?? André3000: I have thought about it but i'm really looking for the easy way to do it as i'm trying to sell the car but if it doesn't sell there will be an m50 going in P.S (But if anyone is interested in a m20 b25 engine I have two which I can sell (1 mint other needs new piston rings) PM if interested would like around a 1g for both.) Quote Share this post Link to post Share on other sites
Eagle 1680 Report post Posted October 1, 2012 I used a PFL block on my FL 325i with all the original FL components. Don't remember having any issues. I think PRL block was 9.5 CR compared to 8.8 CR on FL iirc Quote Share this post Link to post Share on other sites
byza213 1 Report post Posted October 1, 2012 if i had the funds id buy it man to chuck in e21 later on! Quote Share this post Link to post Share on other sites
BM WORLD 1286 Report post Posted October 1, 2012 Still haven't sold the engines yet so the bank balance is quite empty Ok, the other engine is striped appart from the manifold, head and block. So basically the fl loom will attach to all the pfl plugs on the engine?? André3000: I have thought about it but i'm really looking for the easy way to do it as i'm trying to sell the car but if it doesn't sell there will be an m50 going in P.S (But if anyone is interested in a m20 b25 engine I have two which I can sell (1 mint other needs new piston rings) PM if interested would like around a 1g for both.) use all the face lift sensors , electrics , front damper hub etc etc , only use the old block , and manifolds should be ok Quote Share this post Link to post Share on other sites
Deano 1 Report post Posted October 5, 2012 Pfl or pre 88 are 9.7:1 block code 25 6E 1 Fl SA build 9.4:1 block code 25 6E 2 Fl US spec 8.8:1 block code 25 6K 1 or 2 Quote Share this post Link to post Share on other sites