more about the set up and parts in her.
Valve Springs ??????
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 901
Likes: 1
From: Oxford PA
Valve Springs ??????
Ok took the car today had it up on rollers. Car put down a decent number all things considered. But my power curve stopped somewhere around 5200rpm and basically went flat... I am leaning torwards valve float?
The cam is just under .600 running the AFR 225 small bore heads. I would like to do spring swap as these spring have 20K street miles on them. Be nice to get a good idea of a spring to recomend. Heard of some of the patriot springs failing so really dont want to go there. I would rather spend a little bit more money and get something a wee bit better.
The cam is just under .600 running the AFR 225 small bore heads. I would like to do spring swap as these spring have 20K street miles on them. Be nice to get a good idea of a spring to recomend. Heard of some of the patriot springs failing so really dont want to go there. I would rather spend a little bit more money and get something a wee bit better.
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 901
Likes: 1
From: Oxford PA
[IMG]
[/IMG]
crappy phone pic but you get the idea... Current springs have quite a few passes on them and about 20K street miles... Just looking at the little magic wave at the 55k mark making me think valve float...
[/IMG]crappy phone pic but you get the idea... Current springs have quite a few passes on them and about 20K street miles... Just looking at the little magic wave at the 55k mark making me think valve float...
Last edited by easyvette; Aug 6, 2011 at 10:55 PM.
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 901
Likes: 1
From: Oxford PA
Build is pretty basic under the hood...
Procharger D-1 (flip drive 8rib)
383 cubic in
AFR 225 heads
American racing 1-7/8 no cats.
cam 226 232...
Going on a massive boost leak hunt in the morining
Procharger D-1 (flip drive 8rib)
383 cubic in
AFR 225 heads
American racing 1-7/8 no cats.
cam 226 232...
Going on a massive boost leak hunt in the morining
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Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 901
Likes: 1
From: Oxford PA
Back playing again this morining. Testing for boost leaks. Was getting alot of air out of the bypass valve. So pulled the bypass (vortech mini race bypass) plugged that off and started testing again. All the piping held pressure up to 30/35psi and then my temp plug let go. What a dam bang that had!!!! At 25 psi the piping was solid!!!
So is the bypass junk now?
So is the bypass junk now?
Le Mans Master
Joined: Oct 2005
Posts: 7,088
Likes: 1,829
From: Metro Detroit Michigan
When you pressure tested, did the manifold have pressure? If you blocked off in front of the manifold, the vacuum/pressure port on the bypass valve wouldn't have had a signal, which it needs to work properly.
Racer
Joined: Aug 2006
Posts: 401
Likes: 85
From: Terre Haute Indiana
For what it's worth, that's graph is exactly what mine looked like before I swapped springs b/c of valve float. Mine died off around the 5200-5300 range just like yours. Search for my name and you'll see my graph. I made another thread with the end results afterwards.
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 78
From: Forney Texas
It's the bypass valve. It's the easiest part to replace. Replace it and head back to the dyno. You'll see what you're looking for. 
The springs might be a contributing factor, but you're losing more boost than you might think out of that POS Vortech bypass valve.
Replace it and just look at how much boost you pick up. That will give you an indication of whether or not you can expect to do better on the dyno.
The springs might be a contributing factor, but you're losing more boost than you might think out of that POS Vortech bypass valve.
Replace it and just look at how much boost you pick up. That will give you an indication of whether or not you can expect to do better on the dyno.
Last edited by BLOWNBLUEZ06; Aug 7, 2011 at 04:16 PM.
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 901
Likes: 1
From: Oxford PA
Have a Big Mondo valve here on the shelf so thats the first plan of attack... Just trying to figure out where the hell to put this beast of a valve.
As for when I tested it. I took the entire intake out of the loop. The rockers are still on in the car figured the air could have found an open valve. So capped of the intake coupler with a plug also. Basically in the end had the charge pipe from the supercharger plugged and the intake charge pipe plugged and the bypass valve plugged becasue the bypass was leaking alot of air. Going to get this new bypass valve on and test again to see how much air comes out if any compared to the last test. From there its gonna be borrow a big red procharger valve for test purposes.
Arun as for spinning yep I am overspinning the heck out of it... I was about 3K over max impeller and spoke to a tech off the record and he said I should be fine. That was with the 3.4 and the inovators west damper. I do plan on spinning this thing until it totally runs out of steam. I dont think its out of steam being about 3K over its not the most effiecent thats for sure.
As for when I tested it. I took the entire intake out of the loop. The rockers are still on in the car figured the air could have found an open valve. So capped of the intake coupler with a plug also. Basically in the end had the charge pipe from the supercharger plugged and the intake charge pipe plugged and the bypass valve plugged becasue the bypass was leaking alot of air. Going to get this new bypass valve on and test again to see how much air comes out if any compared to the last test. From there its gonna be borrow a big red procharger valve for test purposes.
Arun as for spinning yep I am overspinning the heck out of it... I was about 3K over max impeller and spoke to a tech off the record and he said I should be fine. That was with the 3.4 and the inovators west damper. I do plan on spinning this thing until it totally runs out of steam. I dont think its out of steam being about 3K over its not the most effiecent thats for sure.
Le Mans Master
Joined: Oct 2005
Posts: 7,088
Likes: 1,829
From: Metro Detroit Michigan
Since the intake manifold is blocked off, I think you will also need to apply pressure to the small hose going to the bypass valve to know if the valve is leaking under actual boost conditions.
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 901
Likes: 1
From: Oxford PA
Good call... Never thought about that one when I took the intake out of the loop... Already cut the little bypass flange off so its going to be the big guy regardless. The bigger vale has a much bigger chamber on top of the hat for a better hold back ratio... But I will remember that when I retest this valve on the flange before it goes in the car.
