408 with single Turbo T76??
Thread Starter
Teching In
Joined: Mar 2007
Posts: 23
Likes: 0
From: Westfield, IN
Originally Posted by ocdwill
tim go 88 ....just do it. better safe then sorry...the car will be bad eather way but more is better...
If I do not sell we will dyno with 76 and see what happens, then if I want to go up more in HP
then I will go 88 but it is a T6 vs T4 and will have to change mounting bracket. I may just have to drive around with 650hp instead of 750 for a while. 
Thread Starter
Teching In
Joined: Mar 2007
Posts: 23
Likes: 0
From: Westfield, IN
Thanks
Originally Posted by Earl H
Titan,
You are getting many of the same answers I got when I was looking at doing a 4XX motor with my T76gts...well, only then the S88 wasn't avail. In the end, I ended up going with a different motor combo and twins.
You are getting many of the same answers I got when I was looking at doing a 4XX motor with my T76gts...well, only then the S88 wasn't avail. In the end, I ended up going with a different motor combo and twins.
Earl,
I know we have posted on the corvette forum also about this project what in your opinion is the downside to the 76 in regards to Backpressure? Is the 76 not going to be efficient so once I get over app. 650-700 that I loose power or could hurt motor?
Or is it the case that to make 750-850 I need a 88 on 408ci and nothing is wrong with 76 just will not make that kind of power?
Thanks
I agree with others that a bigger turbo would make the power easier, but I think it's only going to take 12 PSI or so to make the numbers we're looking for. I'm sure this turbo is capable of making that on the 408. Considering we already have the turbo, and the setup is proven and works well, I think this is the best way to go. Since we're already throwing money at this project with both hands, I think it's wise to use what we have, and if we need to change it later, it's no big deal.
If anyone insists on seeing a bigger turbo on this engine right away, donations can be made to: Gymtitan, C/O Late Model Speed at the address in my sig
Ed
If anyone insists on seeing a bigger turbo on this engine right away, donations can be made to: Gymtitan, C/O Late Model Speed at the address in my sig
Ed
Originally Posted by gymtitan
Earl,
I know we have posted on the corvette forum also about this project what in your opinion is the downside to the 76 in regards to Backpressure? Is the 76 not going to be efficient so once I get over app. 650-700 that I loose power or could hurt motor?
Or is it the case that to make 750-850 I need a 88 on 408ci and nothing is wrong with 76 just will not make that kind of power?
Thanks
I know we have posted on the corvette forum also about this project what in your opinion is the downside to the 76 in regards to Backpressure? Is the 76 not going to be efficient so once I get over app. 650-700 that I loose power or could hurt motor?
Or is it the case that to make 750-850 I need a 88 on 408ci and nothing is wrong with 76 just will not make that kind of power?
Thanks
Btw, try selling your turbo on the turbo mustang board or any number of import boards...that turbo size isn't uncommon for them. Also give Brian Cook a call (Vette Forum). He is putting together a single kit (C5s) and might be able to give someone a deal on his hot/cold parts and your turbo. Good luck either way.
Thread Starter
Teching In
Joined: Mar 2007
Posts: 23
Likes: 0
From: Westfield, IN
Working hard
Originally Posted by Ed @ Late Model Speed
I agree with others that a bigger turbo would make the power easier, but I think it's only going to take 12 PSI or so to make the numbers we're looking for. I'm sure this turbo is capable of making that on the 408. Considering we already have the turbo, and the setup is proven and works well, I think this is the best way to go. Since we're already throwing money at this project with both hands, I think it's wise to use what we have, and if we need to change it later, it's no big deal.
If anyone insists on seeing a bigger turbo on this engine right away, donations can be made to: Gymtitan, C/O Late Model Speed at the address in my sig
Ed
If anyone insists on seeing a bigger turbo on this engine right away, donations can be made to: Gymtitan, C/O Late Model Speed at the address in my sig
Ed
TECH Addict
Joined: Jul 2005
Posts: 2,153
Likes: 3
Of course, there are better suited turbo's than the 76 on a 408. However, I don't think 750 rwhp through a locked converter would be a problem. I've made 700 rwhp on a 388 LTx through an auto/loose converter at only 17 psi, plus pulled 146 mph in the quarter at full weight. It'll do about 23 psi before it's out of steam, plus a locked up auto would put over 100 more hp to the tires than my TH350.
Mike
Mike
Originally Posted by engineermike
Of course, there are better suited turbo's than the 76 on a 408. However, I don't think 750 rwhp through a locked converter would be a problem. I've made 700 rwhp on a 388 LTx through an auto/loose converter at only 17 psi, plus pulled 146 mph in the quarter at full weight. It'll do about 23 psi before it's out of steam, plus a locked up auto would put over 100 more hp to the tires than my TH350.
Mike
Mike
Standard 76 or 76gts?
If anybody can make 750 through a 408 T4 standard 76 it's Ed. Since ya have it it's a nobrainer to run it on a dyno. Just for fun I'll bet Ed a coke you stall out in the 600's rwhp. Put a pressure bung in the exhaust between the turbo and the head for grins also
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Staging Lane
Joined: Feb 2007
Posts: 97
Likes: 0
Originally Posted by gymtitan
That's what we will see in a few days on the dyno. I run the chart and it looks like we will be good to 14-15 lbs before the 76 is out. Of course if we also add the spray the numbers will change. Ed didn't you promise 750rwhp on street tune to my wife?
lol... Ed, you in deep poop!! never promise the wife things......you know that....she might tell her man to beat you up..lol
Thread Starter
Teching In
Joined: Mar 2007
Posts: 23
Likes: 0
From: Westfield, IN
Originally Posted by ocdwill
lol... Ed, you in deep poop!! never promise the wife things......you know that....she might tell her man to beat you up..lol
Dam you do know me to well. That is just to funny and it has been a while since she asked me to do that.
Originally Posted by engineermike
Of course, there are better suited turbo's than the 76 on a 408. However, I don't think 750 rwhp through a locked converter would be a problem. I've made 700 rwhp on a 388 LTx through an auto/loose converter at only 17 psi, plus pulled 146 mph in the quarter at full weight. It'll do about 23 psi before it's out of steam, plus a locked up auto would put over 100 more hp to the tires than my TH350.
Mike
Mike
Originally Posted by gymtitan
Ed didn't you promise 750rwhp on street tune to my wife?
Maybe, but she was feeding me hot wings and beer, so I can't really be held accountable....Iwould have agreed to damn near anything
Originally Posted by onfire
Standard 76 or 76gts?
If anybody can make 750 through a 408 T4 standard 76 it's Ed. Since ya have it it's a nobrainer to run it on a dyno. Just for fun I'll bet Ed a coke you stall out in the 600's rwhp. Put a pressure bung in the exhaust between the turbo and the head for grins also
If anybody can make 750 through a 408 T4 standard 76 it's Ed. Since ya have it it's a nobrainer to run it on a dyno. Just for fun I'll bet Ed a coke you stall out in the 600's rwhp. Put a pressure bung in the exhaust between the turbo and the head for grins also
Thanks Tom, you're on,but if I win, I'll want pie with it!
I'll take some pressure measurements for you.
Ed
Staging Lane
Joined: Feb 2007
Posts: 97
Likes: 0
Originally Posted by onfire
update?
Last edited by ocdwill; Jun 3, 2007 at 08:18 PM.