Turbo or 3.0 Stroker?

[chameleonleather]

6k?!

s52 swap.

m20 turbo for auto-x is not great. on the track is just about setting up your car suspension. that's what coilovers are for...weight transfer

and how in the hell do you make a 2100lb e30?!

Sorry 2400lbs. Although with a M42 set up 2100lbs is not unheard of. Basically bare shell with some panel cut away or replaced with lighter material.

[mikeedler]

dude, I have no idea what you are want to use that adds an extra 70lbs.-- my turbo cars turbo manifold is lighter than the stock, the blow off with alu. piping weighs about 5lbs and the turbo with the wastegate weighs nowhere even close to 25 lbs.-- and you will get alot more than 50hp if you do it semi correctly.

i say turbo if you want to go fast, but if you want it for curves dont get a very large turbo.- if you want something to track, probably without turbo- i dont like driving my turbo car in the twisties at all- it comes on to boost at any given time and if your in a curve it sure makes it interesting.

for the money you will get alot more hp for you $ out of the turbo

[etxxz]

6k?!

s52 swap.

m20 turbo for auto-x is not great. on the track is just about setting up your car suspension. that's what coilovers are for...weight transfer

With the turbo set up it would be built to hit peak torque by 2.5k. Everyone I talk to says if I go with turbo I will be itching for more and more boost, hence more wear and higher cost in the long run. I have taken rides in a 3.1 stroker 2100lbs e30 race car and it's just silly fast. And it wails like a banshee.

and how in the hell do you make a 2100lb e30?!

[chameleonleather]

With the turbo set up it would be built to hit peak torque by 2.5k. Everyone I talk to says if I go with turbo I will be itching for more and more boost, hence more wear and higher cost in the long run. I have taken rides in a 3.1 stroker 2400lbs e30 race car and it's just silly fast. And it wails like a banshee.

[Jon325i]

Both are tempting propositions - of course, the ultimate solution would be to build a 3.0L stroker with turbo :)

Going with the stroker route, the mechanical complexity of the motor is going to remain largely unchanged. You mentioned doing MegaSquirt (a good thing) but aside from that it should be as durable and no more complicated to work on/maintain than a stock M20. I've had a chance to ride in a E30 with a 3.0L M20 and although it wasn't totally finished off and tuned well, it still had an impressive amount of torque down low which made for snappy take offs.

With the turbo, there's obviously more "stuff" bolted onto the engine and maintenance & repairs may become a bit more involved to do depending on how the forced induction set up is installed in the engine bay. No doubt this would be a fun package to run and you can set it up conservatively with a smaller snail to bring on boost early for better low end grunt (like a stroker) or go for more mid-range and/or top end punch. Of course, if you go with a more extreme turbo set up many internal changes will need to be made to cope with the stress expected. Check out http://www.turbochargingdynamics.com for a nice set up - albeit at a price - which it set up to work with stock M20 internals.

I guess which one to go with is going to boil down to your preference and driving style. Some like the power down low, others prefer maximum fun as the tach nears redline.


Jon

[chameleonleather]

This is exactly the insight I'm looking for. At this moment the M20 is going through a rebuild and I'm torn between building a stroker or build it for turbo. Most people say turbo of course, but that’s 70 lbs up front! In my opinion it is one thing going fast in a straight line and another driving fast on the track or autox. I would love the extra 50hp from the turbo but this is also a DD. I would love some more guidance. It's going to cost me 6k either way with Mega Squirt and tune. With the stroker it will be all new parts with s50 crank and custom pistons, cam, rods, rockers and springs (the whole nine yards)...and with the turbo it will be a stock rebuild salvaging as much parts as possible and using a comatic gasket.....I'm leaning towards the stroker just for the "new" factor alone.