I'm new here guys! i dont have a buick GN, but i joined this forum cause you guys are turbo junkies and know your stuff. I have a '70 camaro rs/z28 with a 406 pushing about 425hp with about 9:1 compression. I was thinking about twin turbos with the budget upside-down header installation or even a single turbo with proper plumbing. can anyone tell me what would be the ideal turbo and A/R ratio to make a 9 sec. car with a single turbo? Thanx guys
Need turbo advice please- '70 z28 rs
- Thread starter kree
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I cannot give you an answer, but can offer some help.
There are 2 dominant Garrett distributors that have been great suppliers to our Buicks and they do lots of other vehicles too.
PTE can be reached at: 219-996-7832
Limit Engineering at: 928-453-7321
Thanks for visiting and let us know how it works out!
There are 2 dominant Garrett distributors that have been great suppliers to our Buicks and they do lots of other vehicles too.
PTE can be reached at: 219-996-7832
Limit Engineering at: 928-453-7321
Thanks for visiting and let us know how it works out!
first thing would be, are you running some kind of efi or a carb? if your going carberated, forget about it, your MUCH better off with a blower. from what i have seen the guys who run twin turbo setups usually have pretty small turbos, like te33, having 2 of them works out to be about the same as a +/- 66 with less lag thanks to their smaller size. if I were you I would really concider a single turbo, they can make about the same power and its a whole lot less complicated, and cheaper too. I'm not a turbo expert at all, but I think I would start out with something cheap and go from there, like a used gn turbo, see if its over kill or not enough before you spend lots of money on a new turbo. just my thoughs.
Thanx guys - some specific questions....
First off, I'd like to thank everyone helping me out on this. Your advice is much appreciated. After doing some homework I am leaning toward a single turbo. My engine specs can always be adjusted (cam,stall speed etc.) What I really need to know is what turbo is best for my 406 to get into the 9's. Since the baseline of my 406 is higher than what a stock 3.8 would be without a turbo (approx. 400+hp), can I get away with using a turbo thats not as serious as the ones that GN's use to get into the 9's. For example, would I be able to pull it off with a PT60 series turbo? Or can I do it by running less boost. ie. 15psi instead of 22+psi? What would be the best trim size for use with my displacement? What would be the ideal A/R ratio? and How can I calculate this? Also, what is the best way to handle the oil return line from the turbo with a small-block chevy? I do have a supercharger-ready carb, so what would be the problems assosciated with this setup? I was contemplating using a carb with an extra injector before the carb to richen the mixture according to boost. What would be the best EFI system to use for my setup? I was thinking of converting my edelbrock intake by welding in bungs on the runners for the injectors, then using a 90 degree pipe on top where the carb would be and mounting a throttle body to it. However, if I do this, what should I use as an ECU to controll it? I know there are a lot of questions guys, but its the only way to learn. Thanx once again guys.
First off, I'd like to thank everyone helping me out on this. Your advice is much appreciated. After doing some homework I am leaning toward a single turbo. My engine specs can always be adjusted (cam,stall speed etc.) What I really need to know is what turbo is best for my 406 to get into the 9's. Since the baseline of my 406 is higher than what a stock 3.8 would be without a turbo (approx. 400+hp), can I get away with using a turbo thats not as serious as the ones that GN's use to get into the 9's. For example, would I be able to pull it off with a PT60 series turbo? Or can I do it by running less boost. ie. 15psi instead of 22+psi? What would be the best trim size for use with my displacement? What would be the ideal A/R ratio? and How can I calculate this? Also, what is the best way to handle the oil return line from the turbo with a small-block chevy? I do have a supercharger-ready carb, so what would be the problems assosciated with this setup? I was contemplating using a carb with an extra injector before the carb to richen the mixture according to boost. What would be the best EFI system to use for my setup? I was thinking of converting my edelbrock intake by welding in bungs on the runners for the injectors, then using a 90 degree pipe on top where the carb would be and mounting a throttle body to it. However, if I do this, what should I use as an ECU to controll it? I know there are a lot of questions guys, but its the only way to learn. Thanx once again guys.
Boy, you are in need of A Plan! First off, if you are serious about going turbo, get the book "Maximum Boost" by Corky Bell. Lots of info in there about adding a turbo to a car. You'll find lots of answers there. How to do a carb setup, carb vs. efi, oil supply and return, etc... is all there.
Until then, I can help you get an estimate of the turbo size you'll need and whether your fantasy is realistic or not. Let's start off simple: you say you want to run 9's. How much flywheel hp do you think that will take in your car? What is the redline rpm of your engine?
John
Until then, I can help you get an estimate of the turbo size you'll need and whether your fantasy is realistic or not. Let's start off simple: you say you want to run 9's. How much flywheel hp do you think that will take in your car? What is the redline rpm of your engine?
John
