3-Series (E21, E30)Chat relating to the BMW 3-Series from 1975-1983 and 1984-1991 line. Specific models: BMW 315, BMW 316, BMW 318, BMW 318i, BMW 320/4, BMW 320i, BMW 320/6, BMW 323i, BMW 320i. E30 Family models include: BMW 325e, BMW 325i, BMW 325is, BMW 325ix.
Alright guys, im new to the forum, i dont own a BMW but my friend does and he doesnt have internet access, so he relys on me to do his research for him, which i dont mind.
First off, im in the process of Turboing my VW Bora, 24v VR6, GT35r Turbo, 034Motorsports standalone, etc etc etc.
I was wondering if i could gather some info on turboing the 2.7L motor that came in the 325es in 86.
Who sells a kit?
if there is no kit, who sells the parts, i.e., manifold, chip, etc.
im trying to steer him away from doing a 95 325i motor swapm only said to be like 180hp or something?? i think a turbo setup would be better.
Yes, I'm doing the same thing, however with 9:1 compression raito boost over 4-5 lbs gets you into trouble fast.
Now that I have gas (for my welder that is) I'm going to finally build my inexpensive turbo manifold that I designed for bugget builders. If interested we can talk about setting him up with one for a good price.
BTW, I find that odd that they call the VR6 a DOHC. The VR6 is really a V6 with one cylinder head and one cam runs each bank. To be technical about it the VR6 is in reality a SOHC because to "truly" be a DOHC you need 4 cams per bank.
they changed the engine when they went from the 12v to the 24v, it is now a DOHC and can support 500whp on 8:5:1 compression. It is also offset 15 degrees instead of 45 or 30, its almost like a inline six. VR6 translates to Vee-Rehein motor six cylinder, which means Inline Vee. Crazy germans
how much boost you add will be directly dependant on how much fuel you add as well as how cool you can get the intake charge.
With that much compression, you will be limited due to the fact that the pistons and valves are not made for high cylinder pressures and heat. It also does not help that there are no piston squirters to help cool the pistons as well.
Anything can be boosted, as I am sure you already know with previous experience.
yes anything can be boosted with enough prep... if you boost to high and the pistons arent made for the pressure... well yeah bye bye pistons... there is always some prep in changing parts if you want to go crazy with boost...
Melted pistons, blown head gaskets and burnt valves are most common. For boosted motors lower compression pistions are better, ideal ratio is close to 7.5:1 to 8:1.
Here is a few guide lines for turbocharging motors:
#1 For every 1 psi of boost raises the compression raito about .5 psi.
#2 For every 1 psi of boost raise the octaine rating by 2-3 points.
#3 1 psi of boost raises your ambient air temp in the intake by about 12-13 degrees F
#4 For every 10-15 degree raise in ambient air temp raise the octaine rating by about 1-2 points.
#5 Effective intercooler surface area should be about 12 square inches for every 5-6 psi anything less no intercooler is needed and more intercooler space raises turbo lag.
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.