Supercharger and a Auto
I have a TH350 with the modulator (cant get a manual valve body for a TH350C) and I am not using anything on the line. Problem with a check valve is if you go into boost quick is it may hold vacuum in the line so unless you find a check valve that can vent quickly its a bad idea.
I took a stock aftermarket modulator and ran 25psi into it and it didnt move from where it sat with zero vacuum. So at boost it will be in the same position as zero vacuum or wot/high load on a n/a car. Unlike a non bypassed positive displacement (roots type) blower, manifold vacuum with a centrifugal supercharger is just like a n/a car until you are really into it, zero vacuum or 10lbs of boost and the valve is in the same position. I have had no problems at all with the modulator hooked up directly.
I took a stock aftermarket modulator and ran 25psi into it and it didnt move from where it sat with zero vacuum. So at boost it will be in the same position as zero vacuum or wot/high load on a n/a car. Unlike a non bypassed positive displacement (roots type) blower, manifold vacuum with a centrifugal supercharger is just like a n/a car until you are really into it, zero vacuum or 10lbs of boost and the valve is in the same position. I have had no problems at all with the modulator hooked up directly.
Try this simple test, put a vacuum gauge between the modulator and the check valve and see what happens. The gauge will go to 15-18hg of vacuum and stay there so the modulator will never close. Thats what the check valve is for on your brake booster and canister for the vents under the dash is there for, pull the check valve off the booster without the car running and see what happens. If you put a simple one way check valve in the modulater it will do the same thing when you pull the hose off between the check valve and modulator.
I have read in places that the modulator diaphram will rupture over 6psi, and thats why 99.9% of most trans builders dont recommend a vacuum modulated transmission in a boosted car. That may have been true of the old big canister modulators but not the newer ones. Unless FLP has some sort of arrangement so it only closes at positive pressure its not a good idea IMO. 3,000 miles and 115 passes later I still havent ruptured the diaphram with 7-8psi.
I have read in places that the modulator diaphram will rupture over 6psi, and thats why 99.9% of most trans builders dont recommend a vacuum modulated transmission in a boosted car. That may have been true of the old big canister modulators but not the newer ones. Unless FLP has some sort of arrangement so it only closes at positive pressure its not a good idea IMO. 3,000 miles and 115 passes later I still havent ruptured the diaphram with 7-8psi.
Last edited by kp; Apr 16, 2004 at 12:12 PM.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
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
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Originally Posted by KraZy
Should I be worried about my tranny (new and rebuilt for power) when i put my Procharger on?
Thread Starter
Joined: Nov 2001
Posts: 3,066
Likes: 0
From: Sunny San Diego
Originally Posted by Got Me SOM
Ed are you gonna go boost now? My car should be going in for a Vortech next week.
One of the main reasons I never considered a Supercharger. The Vortech would have be an good solution, cause they were already smog legal. But I would have to cut my hood.
Just have to work out my CR issue.
if you have a regular z28 you don't have to cut your hood. I like the power of the ATI's but they have problems, ie belt slipping issues, and for some reason they need to be paid more attention to than the Vortech kits.
Vortechs cost more but no one has reported any issues similar to the ATI's..
just word of caution, have money stored away just in case you have to build your bottom end.
I like the Vortech cause of the proven aftercooler system.
just my thoughts.
Good luck. Either way bottles are babies, real men get blown!
Vortechs cost more but no one has reported any issues similar to the ATI's..
just word of caution, have money stored away just in case you have to build your bottom end.
I like the Vortech cause of the proven aftercooler system.
just my thoughts.
Good luck. Either way bottles are babies, real men get blown!
Thread Starter
Joined: Nov 2001
Posts: 3,066
Likes: 0
From: Sunny San Diego
I have the SS hood. So with the Vortech I would have to cut. 
I only plan on pushing 5 psi. So hopefully I won't to many issues with the belt.
And yes. I have $$$ set aside. You have to pay to play.
I had a blower on my old V6 Camaro. I do miss that whine.
How about blown and bottle fed.
I only plan on pushing 5 psi. So hopefully I won't to many issues with the belt.
And yes. I have $$$ set aside. You have to pay to play.
I had a blower on my old V6 Camaro. I do miss that whine.
How about blown and bottle fed.
Hey Ed I have a SS too and fawk it I'm gonna cut the hood but the instructions show you how to cut and where to cut so it won't mess it up that bad. You can always buy another hood later I guess, if you return back to stock, which I doubt you'll ever do!
boost and nos-nice! not on stock bottom end though..
all you have to do is put 9:1 pistons and rods and you can go to 12 psi safely and that should net you 550 rwhp easy. That in an automatic would be awesome. Then you squeeze some to hit the 600 mark or use it just for "emergencies"
boost and nos-nice! not on stock bottom end though..
all you have to do is put 9:1 pistons and rods and you can go to 12 psi safely and that should net you 550 rwhp easy. That in an automatic would be awesome. Then you squeeze some to hit the 600 mark or use it just for "emergencies"
