s38 swap

[Schneller Bayer]

I was recently enticed by the idea of dropping an s38 from the e34 m5 into a 99 m coupe. How possible is that? I like the idea of factory motor behaviour as opposed to forced induction problems. Naturally, as there never is enough power, that will come along, but for now i like the notion of an OE engine making 340 bhp in an m coupe. Last I checked, that m5 engine doesn't weigh much more, if at all. If it is too heavy, some minor work can be done (moving the battery to the trunk, carbon fibre/fiberglass hood, etc.) whaddaya guys think? Is it possible (with this I mean reasonably unproblematic kind of possible)? That will make a mean m coupe!

[drunknmunky02]

I think you will run into some fitment issues, as always. I'm sure you can fab brakets and the like, but the intake manifold is large and the length (front to back) may be an issue. I'm pretty sure you will have to get a new(used) tranny. The s38b35/36/38 are based on the M30 (aka-Big 6) engine (in 80's e24/28/23/34). The S50/52/54 is based on the "Small 6" engine (3 series e30 to current). This means most likely a custom drifveshaft and shifter components. I seem to remeber a guy doing it in an E36 but I don't remember how it turned out or if it turned out well.

Don't the "newer" M coupes have a similiar engine to the E46 M3? I'm sure you can find a motor from a wrecked Mcoupe/e46 M3 for the same price as a e34 M5 if not less. Pricing I have seen is close to $5500 for M5 engine, if not more. Lot more E46 M3's and new Mcoupes running around then there are people willing to part with their S38.

[Eric]

Originally posted by Schneller Bayer
I was recently enticed by the idea of dropping an s38 from the e34 m5 into a 99 m coupe. How possible is that? I like the idea of factory motor behaviour as opposed to forced induction problems. Naturally, as there never is enough power, that will come along, but for now i like the notion of an OE engine making 340 bhp in an m coupe. Last I checked, that m5 engine doesn't weigh much more, if at all. If it is too heavy, some minor work can be done (moving the battery to the trunk, carbon fibre/fiberglass hood, etc.) whaddaya guys think? Is it possible (with this I mean reasonably unproblematic kind of possible)? That will make a mean m coupe!

M5 motor is way heavy, don't do it. you could build your motor to the same power as the M5 motor easily

[Ryan Stewart]

Yeah man, why go to older technology and a larger block in such a tiny car?

Do the ODB1 conversion and some cams and you should be happy with a power increase.

I hate to tell you but what you really need is a good aftermarket radiator and and oil cooler. The problems with the M coupes is all in not being cooled enough.

[jinxed84]

AA has a siiiiiick mcoupe with the S52.


mmmmmmmm 469whp



or you could just put an s54 in there, it came with one in the last years of the model anyway.

have fun either way!

[Schneller Bayer]

Thanks for the advice guys! Happy Motoring!

[Qwickm3]

james Clay from Bimmerworld is swapping one into a vert. M3

[Ryan Stewart]

I would assume the MUCH heavier Vert E36 chassis would handle the increased weight much better than the Z car. The Z cars are basically E30s where you sit in the back seat. That is why the Z3 2.8 engine is sought after, its all alum.

[bmwks]

S38's weigh one pound less than a euro S50. Go with it!

[little740girl]

Maybe getting an M coupe with an S54 would be a better idea. Warning signs went up at the idea of swapping for an older engine. Especially one with individual throttle bodies and other fun, race inspired attributes. You'd probably want to do at least a minor rebuild before the swap, then with all of the fitting issues, it would be more adventitious to admit defeat, trade your 99 for an 01, and loose 7hp.

[Schneller Bayer]

Originally posted by little740girl
Maybe getting an M coupe with an S54 would be a better idea. Warning signs went up at the idea of swapping for an older engine. Especially one with individual throttle bodies and other fun, race inspired attributes. You'd probably want to do at least a minor rebuild before the swap, then with all of the fitting issues, it would be more adventitious to admit defeat, trade your 99 for an 01, and loose 7hp.

The s54 is great and super fast, but does not have much more room to play with. F/I is a fortune, and there aren't many possible mods for it. The s38, however, makes a hearty 340 bhp compared to 315 with the s54. If I were to stop there, the s53 would still be a better idea. I'm looking to put down large numbers, like 400+ whp. AA kits are awesome, but way-to-freaking expensive. The s38 also has 600+whp potential. that would be very pricey, but more than anything I would ever get out of an s52 or s54 for that money. Either way, I don't mind going with any engine if it produces numbers, and an s38 is not too heavy, a good stepping stone into further realms of extreme speed. The s38 goes where no s52 can go, and especially where no s54 can go. Still, I want 400+whp, but not the 31 000 that the AA kit costs. I saw ATP's kit, but given it's rookie status and mediocre software/customer service reputation, I'm nervous. Mechtech looked good until I found out it didn't produce much more than 300 whp. Cartech didn't seem promising, either. I did, howver, somewhere on dtmpower hear about or see an m3 with a mosselman kit with a larger turbo and intercooler, making huge gains. Any info on that? Any further advice on reaching 400+whp without spendin AA money? And for the doubters, I would never go without Water alcohol injection at those power levels.

[ajw45]

The cost of FI is nothing compared to the cost of building an s38 to 400 hp NA. You're talking an $15-20K+ 4L s38 engine to get 400hp NA, forget about the rest of the costs associated with the swap. Turbo your s52, make more power, and save some $$$. I think it would be pretty badass, but don't try to rationalize the cost over a turbo cause it is just flat out much more expensive.

[Schneller Bayer]

for the 400+whp, I would still turbo or super the s38. However, If I go with turbo, it'll make more power than a turbo s52 with some adjustments. 400whp NA would be the best, and if I had the money (which I don't) I would do that. That is however, completely out of the question for me. It sounds simple to say, "just turbo it", but there aren't many kits. AA is a 30 grand conversion, and the others aren't fully reliable in my books, and don't put the same numbers down. I just want the best way to go fast. An s38 will not be a turbo or super s52, but as money flows in, it will later overshadow the other engines. I would have to wait a while to turbo an s52, but I could sooner swap the s38, and make good power in the meantime.

[Schneller Bayer]

by the way, ajw45, you're car is freaking hot! I've always been an 8 fan. One of the few cars that I would buy just because it looks so good!

[Phillyvanilly]

Hartge puts the 5 litre V8 (dont know the engine code, pardon my ignorance) in Z-cars. Whichever of these options you choose it will be a sweet car, but my stomach turns a bit at the thought of doing a swap on a car that rare. Theyre hard to find, but if you can I say buy a Z3 coupe and do the swap on that, you dont have to feel bad about bastardizing an //M car and you'll also be able to beat the crap out of it on the track.