Was on e30 tech reading about turbos

[llll1l1ll]

and one guy did his for 1500. He has a whole article on it. Anyway, I'm gonna take up that project, but the only thing is that my car's engine has nearly 200k miles on it. Should I do a little bit of a rebuild, get a new engine, or just leave it? Kind of an idiot question, but I felt I should ask it since I really want to do this. Also, if I rebuilt the engine, or sorta rebuilt it (just like, quick rings and a little bit of a head job), how much would that run me? Any place to get a cheap, used engine with maybe around 100k miles on it? Any help is appreciated!

[darien28]

rebuild you head (250-400), get a td crank(250-300), low compression pistons (400-600)... you could use stock crank, but it's not recommended.

[llll1l1ll]

Forgot to add, I drive an '88 325is

[LowR3V'in]

On the forged crank... Don't wast your money on it unless you plan on boosting into the 500+hp range...

Stock is fine :up:

[darien28]

but if you're rebuilding, might as well spend 250 for that extra security... unless you really can't afford an extra 250. >_< I got mine for 265 shipped.

[rscheiring]

I read over Corky Bell's book "Maximum Boost". Its a must read. I just got it out of my library, so cheap enough.

Seemed to me that if you wanted to bolt on exh. manifold, turbo, wastegate and intercooler (and pipe it al together) you would be in that $ range if DIY. But there is only so far you can go with stock fuel pressure, pistons (compression a bit too high), injectors, intake manifold, downpipes, etc etc). So the boost that would provide is small (5-9psi), providing mostly acceleration value. I think hp would be in the 220-240 range (at the flywheel).

It seemed to me for less $ you can get there more conventional ways - 4.1 LSD, higher compression pistons+crankshaft, etc.

This opinoin is completely theoretical - anyone with practical experience on this to agree or disagree?

[PeterCip]

maximum boost = great read...
but you are mistaken, 8.8 is not high compression by anymeans, and you can get well over 250 HP out of the M20 without swapping the crank. Fuel you are right about, it will have to be dealt with. TCD is on here and he is pushing I think 14 PSI?
I was boosting 7.5 psi and got 276/296 on the dyno, now I am at 10 psi and I can tellyou its a lot more power.
The M20 is quite good at taking the extra power..the clutch on the other hand is not. ask matt---
1500 sounds great and all, but once you start getting into it, you are gonna spend more money. it is the little things that get you, head bolts, gaskets, accesories gauges, etc.
good luck with your project. it is a fun task...
now If I could only tackle the body work...
-pete

[rscheiring]

Pete - I'll only believe you when you come install one in my car ;)

[llll1l1ll]

Yeah, for right now I'm only planning on having it being boosted low, around 5-6 psi. So, I'm figuring stock internals would be ok, considering this guy has stock internals. I mean, later on I might boost higher, but it'll be a small turbo and whatnot, so yeah, I'm thinking stock internals will be ok. I guess ill just slap some new rings on there and get a headjob. Shouldn't be too bad! But, would I need to alter the compression ratio if I was just running that low 6psi boost? Or can I keep everything the same.

[LowR3V'in]

What's the stock compression? 8.5... :shock: That's very low [Perfect]

[PeterCip]

Pete - I'll only believe you when you come install one in my car ;)

where do you you live? I owuld be down for another project, or at least, I would help you do yours...
-p

[PeterCip]

Yeah, for right now I'm only planning on having it being boosted low, around 5-6 psi. So, I'm figuring stock internals would be ok, considering this guy has stock internals. I mean, later on I might boost higher, but it'll be a small turbo and whatnot, so yeah, I'm thinking stock internals will be ok. I guess ill just slap some new rings on there and get a headjob. Shouldn't be too bad! But, would I need to alter the compression ratio if I was just running that low 6psi boost? Or can I keep everything the same.

Listen, don't worry about the internals. they will hold and treat you just fine..just remeber to swithc to either head studs or a grade 12.9 socket heat cap machine screw, I think they are m12 x 1.5? don't worry aout your rings unless they are bad to begin with and the head job may be over kill. asess what needs to be done and what doesn't.

6 is low boost and will give you about 250ish HP. more than enough for our cars. change stuff like the timing belt and clutch, these are the weak links...
PM if you need some more info..
-pete

[diegom6]

forget the internals, just concentrate in the fuel delivery and spark(if you use high boost) I'm runing arround 10 PSI and is fast as hell!

[darien28]

my secret project biturbo e30 in progress.... updates once completed...

I might sldo go into production with my custom parts (manifolds and whatnot).

[rscheiring]

Pete - I'll only believe you when you come install one in my car ;)

where do you you live? I owuld be down for another project, or at least, I would help you do yours...
-p

I'm in MA. Live south of Boston, work in Western Mass (Springfield). What about you?