Still a long way from finished but, wanted to share my project with you guys and though it would be interesting to quiz you guys and get some estimates of horsepower and torque numbers I might expect with this combination. This is my first turbo motor so I'm not sure what to expect and I'm certain I'll have a learning curve. Its a LT1 350, the motors not built yet because I 'm still using it for mock up. The turbos are Garrett GT32's with 71mm compressors and a T3 .78ar turbines and, I'll be using AFR 190 heads with about a 8 to 1 compression ratio. The cam motion camshaft is 220 218 @ .050 lift and .553 .531 lift on 114 lca. It is inter cooled and will have water/alcohol injection.
My initial goal was only 600rwhp but who knows, only the dyno will know for sure. Anyway, It's fun to share and get input, good or bad.
Here's a couple of pictures of the motor and what it's going in.
Be Cool. Ed
05-17-2007 04:09 PM
With proper tuning, I see no reason why you will not hit your goal or be very close to it. Your cam looks like it will be fine for your app, as do your heads. How much boost are you planning on running? This will be the ultimate deciding factor on how much hp you will see on the dyno.
05-17-2007 07:42 PM
I'm thinking about 16 lbs max for boost and the exhaust pressures will probably be getting pretty high. I sort of wish I would have selected a turbo with a t4 turbine housing but, I'm hoping this combination will be entertaining enough.
05-18-2007 06:34 AM
Looks like a fun project. I've never been involved with turbos, so would you mind sharing some of your thought process about selecting turbos and engine components?
05-18-2007 01:00 PM
The whole turbo thing is new to me also. There is definitely science involved in selecting one and I should have spent more time researching. There are so many different variations and types of turbos, it makes your head hurt. I selected mine based on a horsepower level I wanted and input from a Garrett technician. That was two years ago and I've learned more since then and would probably do it differently now. The exhaust side of the turbos I'm using have a T3 mount witch is a smaller housing and should give quick spool up but, they will probably be restrictive at higher rpm. If I had to do it again I would use a turbo with a T4 housing and then I'd have room to grow, not that I need it, with 600 to 700 horsepower and a manual trans the rambler should be a handful.
As far as motor parts, you build like you would for any high horse application. The cams in turbo motors are pretty mild so it won't have that nice choppy idle I like but, It will be way more practical, at that horsepower level than a normally aspirated motor. With the 6 speed overdrive trans, it should get decent gas mileage as well...gonna need that, the way gas is rising :mad:
05-18-2007 02:12 PM
I think that the T3 turbines will be a good match for this as it sounds like it will see the street often. I dont think that they will be all that much of a restriction at "higher" rpms, the import crowd uses them on allot of high strung motors with good outcome. Being that you have the smaller t3, spool up should be good, your compression sounds about right as well for the boost you plan to run. I see this making your goal at the wheels on pump gas easy. What are you going to be running for management?
05-19-2007 07:11 AM
I'll be using a f.a.s.t. bank to bank with wide band o2 and you are correct about a lot of street use. I plan on driving this car everywhere. I didn't want to get carried away with turbo size and camshaft profile because I plan on driving it often. It has PS, PB, AC, PW and air ride suspension so, I built it for mostly for street duty but, it would be a shame to not know how quick it will be in the 1/4 mile so, I'm following NHRA guide lines to make it track legal. I know it would be quicker with an automatic trans but the 6 speed should be fun.