doc

For those with experience on this matter, what turbo, wastegate, etc. are required for a do-it-yourself rear mounted turbo system? And cost. Of course, most of us would need the help of a friendly exhaust shop or fabricator.

The SC and turbo guys on DIY Prom board will need to be consulted for the ECM tuning. I'm comfortable over there.

Lets dont argue the merits or lack of, thats being addressed in the other thread on the STS RMT.

In addition, what boost levels should we (I) be looking for. I have a 10:1 CR 395 now in my IROC. So its not the most boost friendly motor.

So, lets get this thread going:

What turbo manufacturer (part number), wastegate, other required items, or part info & assembly.

askulte

Get a small single turbo, like a T3. Maybe one w/ a larger intake housing for more CFM's on your 395. Keep boost under 7psi. I'd say start at 4-5 psi, and tune from there. Find whatever small, cheap turbo you can, and start fabbing. Get one with an integral wastegate, so it's one less part to fab for the first time. It's easier to get a better setup in steps as you learn through trial and error, since the first try will never be perfect. That being said, any boost is usually better than no boost. Start at low boost, and gradually increase as you're sure the various systems are working properly (oil, fuel, heat, clearances, etc...).

Project

your running 10:1, wee bit high for turbo don't ya think

askulte

Nope! Plenty good enough CR. Lots of LT1's out there running forced induction with higher CR's. It's all about managing combustion chamber temps and pressures.

doc

Yea, I would say (even though I have no forced induction experience) that the 10:1 CR is not too high provide that the timing is set back and I run a proper AFR for my specific hardware.

Besides as posted above by askulte, I would start at low boost, get things dialed in and tuned well, then go up in 2 psi increments. With my motor (or even my LS1 car), 7 to 8psi is going to be plenty. I have no intention to run 20psi boost.

My goal would be to make a minimum of 500Hp at the drive wheels.

askulte: I have been on your website, nice Z28TT project. Can you or others get more specific about the turbo manufacturer and model #, also info on the waste gate. Writing T# does mean anything to me, so please pardon my lack of knowledge on this stuff.

askulte

The logbook link (http://www.skulte.com/logbook.html) from the main turbo page has all the specs, just not well organized... A revised website is on my todo list, but the larger exhaust comes first! Generally, the T numbers are Garret turbochargers, and the larger the number, the larger the turbo (which means it needs more energy to spin, but also moves a larger volume of air). Taking a dinky T2, you'd have it overspooled idling (well, not really, but you get the idea). Read the books listed off the turbo sticky at the top of this forum. They explain sizing turbos well. Since the exhaust has cooled down quite a bit by the time it reaches your RMT, you need a much smaller turbine (exhaust section of the turbo), as it's energy (heat being most of it) that drives the turbos, not flow as some folks (STS cough cough!) like to believe. Less heat = smaller turbine to run efficiently. Compressor sizing is easily done from compressor maps for whatever turbo you are using, and doesn't change with FMT or RMT (just cut it in half if you have twin turbos).

Andris