E30 w/S50 Swap Question

Im seriously considering swapping the M20 out of my E30 for an S50. Ive done a lot of research into the swap, so I dont need input on the logistics, etc. What Im looking for is opinions on whether its worth it? Anyone ever swap in an S5X and regretted it? Can someone give me their driving impressions of an E30 with an S5X in it?

This is a street car that sees a lot of HPDE use, and it will continue that way after the swap. Should I do it?

Car in question:

It feels like the car should have come with the engine stock. Don't listen to people who say that S52 E30s are rockets and it's so much power... it's not, it just becomes a good quick car. Nothing extraordinary but just properly powered. And when you stay out of it, it's a smooth, quiet, modern engine so you'll get good reliability, and a quiet, comfortable ride. Mine is a dedicated track rat and the engine now makes about 900 ponies but even NA, it was great! Ok sure it's not as neutral as an S14 powered car, you can feel it's a bit nose heavy but it's really not a big deal and the power MOOOORE than makes up for what little balance you give up.

Oh and don't get anything other than S52. They are so freaking cheap now that it's asinine to get anything else (I mean M50 or M52).

If I were E30ing again, that's probably exactly what I'd do.

I bought an E30 which had had an M50 swapped in, which I in turn swapped out for an M52 (it was cheap and available, and the M50 had low compression on one cyl). In addition to the peak power bump, it seemed to have a great deal more torque down lower than my friend's M20-powered 325i.

I can only imagine the S52 would be like that but better.

I don't know what the price difference is these days, but if BigD is right and the cost difference is small, why not? OTOH, I didn't feel like I was lacking for power with OBD-I-swapped M52, which to me felt roughly as quick as (and considerably more responsive than) my 2012 WRX.

I moved to the E30 from a 2002, so while the six-cyl E30 may be considered a bit nose-heavy, the improved front suspension over the 2002 always made it feel much more willing to turn (though you could certainly tell it was a heavier car). I ended up with coilovers and camber plates, and though I only made a few autocrosses with it before it was rear ended, it worked really well.

One thing more important than anything else I've said so far: in the name of all that isn't school bus, swap in a faster steering rack while you have the engine out. IIRC, I used a Z3 rack, and it was a massive improvement. I hated how much wheel movement it took just to go around a corner on a city street. Absolutely insane. Of course, you're already driving the E30, so maybe it's not bugging you... I wouldn't drive another non-rack-swapped E30.

S52, OBD-I manifold, 3.5 MAF, turner headers and a tune netted me 235whp in my E30 on a weak headgasket.

It was a BLAST of car. There is absolutely no reason to second guess it. It doesn't lose it's "tossability" and you add 100whp.

BigD wrote: Oh and don't get anything other than S52. They are so freaking cheap now that it's asinine to get anything else (I mean M50 or M52).

Last time I looked, the S5x motors were still well over double the cost of the M5x ones. More like triple, actually. This is going by what I see on the forums, Craigslist, and car-part.com. I'd love to get my mitts on a cheap S52, where are you seeing them?

Tom_Spangler wrote: Last time I looked, the S5x motors were still well over double the cost of the M5x ones. More like triple, actually. This is going by what I see on the forums, Craigslist, and car-part.com. I'd love to get my mitts on a cheap S52, where are you seeing them?

Their relative costs may have remained the same but that's to say the M50 can be had damn near free. In my neck of the woods, there are no fewer than 3 S52s for sale on the local forum, going as low as 2k (Canadian) and have had zero interest for months.

I hear about these cheap S52 engines as well. But they must be zapped up immediately. OTH I can find M50/2 engines all day from $2-600. Add S50/2 cams and a tune and make 90-95% of the power for 1/3 of the cost (from what I am seeing)

If I were to build another one, I would do M52 + S52 cam + tune . . . The M50 we did was no slouch, but the extra tq of the M52 would be awsome. . .

+1 on going straight to the S52 w/ OBD-I swap, headers, cams, ZF trans and 3.64 LSD (70/30 ramps + extra clutch pack) and a custom tune.

It already looks like a track car... don't piddle with it. Go all in.

I'm putting an S54 in mine (in avatar) this winter

Strike_Zero wrote: I hear about these cheap S52 engines as well. But they must be zapped up immediately. OTH I can find M50/2 engines all day from $2-600. Add S50/2 cams and a tune and make 90-95% of the power for 1/3 of the cost (from what I am seeing) If I were to build another one, I would do M52 + S52 cam + tune . . . The M50 we did was no slouch, but the extra tq of the M52 would be awsome. . .

This has been floating around for a long time and it needs to be nipped in the bud. With all those mods, an M52 can get close to the STOCK power level of an S52, and not torque. But why would you leave the S52 stock? Throw the same type of chip and M50 intake on the S52 and you have 250-260whp. 3.2L > 2.8 > 2.5... no way around that, don't kid yourself, it's not a 5% difference.

Strike_Zero wrote: I hear about these cheap S52 engines as well. But they must be zapped up immediately. OTH I can find M50/2 engines all day from $2-600. Add S50/2 cams and a tune and make 90-95% of the power for 1/3 of the cost (from what I am seeing) If I were to build another one, I would do M52 + S52 cam + tune . . . The M50 we did was no slouch, but the extra tq of the M52 would be awsome. . .

As Big D mentioned..............not really.

Well it depends . . . I'm a cheap thru necessity type dude (don't have cash to throw at car parts). But S50/2 cams at the time when I built my M50 was $375 and the tune was $275. And it made ~210 whp and about ~195wtq from the OTS tune. S50/2 were at a minimum of $3000/$4000, respectively, with cams started around $2000 (based on some old data when I built my M50). So for less than $700 my little M50 made 95% of the power of my stock S52. I don't think that's too bad.

Never doubted the 3.2>3.0>2.8>2.5 deal (I've owned, driven, repaired a ton of them). Based on my research and uderstanding (however poor it might be), unless you have the dollars to do it, the M52 + S5x cam + M50 intake + exhaust + tune is an absolute bang for the buck. To date, I have yet to find a S50/2 even within $700-1000 of a similar mileage M52.

If the OP has the dollars, why not skip the S52 and go to the S54 like GPS.

Strike_Zero wrote: To date, I have yet to find a S50/2 even within $500 of a similar mileage M52.

I bought a 110k S52 with good numbers out of an auto M3 for $2200 with the ZF trans included. They are more money for sure but given that all the other stuff - headers, intake, oil pan... etc... cost the same I feel like it's worth the extra 500-800 for the torque.

I'm racing it though - I might have felt differently on a street car. The S54 isn't optional anymore in my class - it's the new baseline. Believe me, writing that check hurt.

Thanks for the feedback guys. This is exactly what I am looking to hear.

ransom wrote: One thing more important than anything else I've said so far: in the name of all that isn't school bus, swap in a faster steering rack while you have the engine out. IIRC, I used a Z3 rack, and it was a **massive** improvement. I *hated* how much wheel movement it took just to go around a corner on a city street. Absolutely insane. Of course, you're already driving the E30, so maybe it's not bugging you... I wouldn't drive another non-rack-swapped E30.

Already have a re-built z3 rack in there. Sooo much better than the stock bus steering rack.

Strike_Zero wrote: If the OP has the dollars, why not skip the S52 and go to the S54 like GPS.

I dont have the dollars for that swap. Its a lot more involved and a lot more dollars for both the engine and getting it running than the S5X's.

Giant Purple Snorklewacker wrote: +1 on going straight to the S52 w/ OBD-I swap, headers, cams, ZF trans and 3.64 LSD (70/30 ramps + extra clutch pack) and a custom tune. It already looks like a track car... don't piddle with it. Go all in. I'm putting an S54 in mine (in avatar) this winter

What engine is in your car now? The S52 you mentioned. Interested in selling as a drop in swap to me

Strike_Zero wrote: Well it depends . . . I'm a cheap thru necessity type dude (don't have cash to throw at car parts). But S50/2 cams at the time when I built my M50 was $375 and the tune was $275. And it made ~210 whp and about ~195wtq from the OTS tune. S50/2 were at a minimum of $3000/$4000, respectively, with cams started around $2000 (based on some old data when I built my M50). So for less than $700 my little M50 made 95% of the power of my stock S52. I don't think that's too bad. Never doubted the 3.2>3.0>2.8>2.5 deal (I've owned, driven, repaired a ton of them). Based on my research and uderstanding (however poor it might be), unless you have the dollars to do it, the M52 + S5x cam + M50 intake + exhaust + tune is an absolute bang for the buck. To date, I have yet to find a S50/2 even within $700-1000 of a similar mileage M52. If the OP has the dollars, why not skip the S52 and go to the S54 like GPS.

Those numbers are VERY impressive.....I'd be curious of dyno type and correction factor used.

When I bought my S52, FOUR years ago I paid $1800 + shipping and it came with a warranty from Vines Automotive in Alabama.

And stepping up to an S54 is a HUGE jump in terms of cost.

In reply to Giant Purple Snorklewacker:

Hehe that was the point of my post (probably was clear). If you got the duckies sitting there, then by all means spend it . . . But there are alternatives.

Sent you a PM . . .

Grinch337 wrote:

Giant Purple Snorklewacker wrote: +1 on going straight to the S52 w/ OBD-I swap, headers, cams, ZF trans and 3.64 LSD (70/30 ramps + extra clutch pack) and a custom tune. It already looks like a track car... don't piddle with it. Go all in. I'm putting an S54 in mine (in avatar) this winter

What engine is in your car now?

It's an open hole. Long story... but there is also a hole in it's old engine.

In reply to z31maniac:

I should've included that in the "why not skip to the S54"

I don't have the dyno plots anymore (lost it in a HD crash).

None of us believed it when the numbers came up, but the backup runs where all close to that number. My stock 99 M3 put down ~220whp and closer to 250 with the tune and M50 intake manifold on the same dyno with the same operator.

Strike_Zero wrote: Sent you a PM . . .

Huh. I didn't get anything.

Try: walter_DOT_gator_AT_gmail_DOT_com

Strike_Zero wrote: My stock 99 M3 put down ~220whp and closer to 250 with the tune and M50 intake manifold on the same dyno with the same operator.

That is pretty typical. I was at 262wHP/252TQ with an S52, schricks, raceland headers, OBD-1, 24lb injectors, euro MAF , out of the box Turner chip and a 7400 redline. The extra torque is what really gives it the edge over the other motors. It pulls harder coming off a corner and you get to keep those extra MPH all the way to the next one.

z31maniac wrote: And stepping up to an S54 is a HUGE jump in terms of cost.

It is also a HUGE jump in terms of power.

I'm sitting on a dyno'd 355wHP and an extra 800+ RPM redline so I can up the gear for even more acceleration w/o losing top end speed vs the S52.

I am soooo excite!

Giant Purple Snorklewacker wrote:

z31maniac wrote: And stepping up to an S54 is a HUGE jump in terms of cost.

It is also a HUGE jump in terms of power. I'm sitting on a dyno'd 355wHP and an extra 800+ RPM redline so I can up the gear for even more acceleration w/o losing top end speed vs the S52. I am soooo excite!

Very very true.

I think the S54 cost is where an LS1 starts to be comparable. But of course, that's not legal for your racing is it?

z31maniac wrote:

Giant Purple Snorklewacker wrote:

z31maniac wrote: And stepping up to an S54 is a HUGE jump in terms of cost.

It is also a HUGE jump in terms of power. I'm sitting on a dyno'd 355wHP and an extra 800+ RPM redline so I can up the gear for even more acceleration w/o losing top end speed vs the S52. I am soooo excite!

Very very true. I think the S54 cost is where an LS1 starts to be comparable. But of course, that's not legal for your racing is it?

It makes the LS look positively cheap in all honesty but, no, no out of family swaps allowed and has to be 3.5L or under.

z31maniac wrote: I think the S54 cost is where an LS1 starts to be comparable. But of course, that's not legal for your racing is it?

Not just that, but V8 swaps in E30s involve more compromises than straight six swaps. Exhaust routing, brake boosters, heater hoses, etc.