JAX04

iTrader: (17)

First off, let me just start by saying, have read threads, i have searched, ive posted in many threads regarding spool valves over the last couple years.


HOWEVER, what i have not found is WHY people are against them....


I have recently seen more then one person say they have "been their, done that, wont do it again" etc. Or something to that affect.


What is their issue? Why are they not liked?

From the data ive seen, between Zombie and SP, they seem to pretty friggin legit, i can understand that getting them to work with your particular setup might be kind of a pain in the ***, and they add "one more point of failure" etc. But ****, lets face it, with all the points of failure in turbo setup, whats one more, lol...

Besides those things, why or why not?

Also, if anyone has a t6 valve, or can make one, shoot me a PM so we can discuss it.


EDIT: Id also like to add this to the discussion, Assuming a person has decided to full on go with a valved idea, be it wastegate method or flapper valve, Which side of the turbine housing is best blocked? From a few diagrams it would seem they are not symmetrical...

98Z28CobraKiller

iTrader: (17)

There seems to be more than one way to skin this cat. Some use a flap type deal that covers up one side of the twin scroll exh housing and others like Zombie (IIRC) used a wastegate to do it with a pipe plumbed into the bypass side. I can see the wastegate method being far more reliable.

JAX04

iTrader: (17)

I have seen both systems used to success, however that can be measured.

My one issue with the wastegate method, Minding that i believe it too be far more reliable as well, is the fact that flow of exhaust just doesnt look good in my head, lol.

Valve is still a straight through design when full open, a wastegate is a 90* bend.

Now, maybe im just thinking WAY to far into that, and it would actually have a very small impact on the velocity, or whatever????????

EDIT: for what its worth, ive even got a few pics of people building them right into the divided housing itself.

EDIT: Added another question in green to add to the discussion in the OP

Tiago

iTrader: (27)

we used one in a Supra with a 3.4L stroker and a GT4508R and I gotta say it had more area under the curve than my TA with the 427 and twin 76s... it was awesome to drive on the street.

when we took the car apart 2 years later though, the middle devider on the valve was pushed out and almost completely separated, and about to go through the turbo catastrophically... so we pulled it out just in time lol.

black98ws6ta

iTrader: (77)

I used a Spool valve made by one of the companies that threw in the towel. It had a problem with seizing and I spent alot of time trying to modify and make it work. I even used a air solenoid and nitrous pressure to actuate it. I'll take a properly sized turbo over the trouble I had any day. Maybe some of the more expensive valves (SP) work perfectly?

JAX04

iTrader: (17)

Thanks for the input guys, i appreciate it, i have not made my mind up yet on what im doing.

I know im using no larger then say 330-352CI for the next engine, i was told this is going to be the size where the HP88 thrives. With that said, im just trying think of ways to maximize my spool on and off the track.

I know their are things you can do at the track, timing, afr, the 2 steps and transbrakes help alot, but those things wont get used from a roll. As much as i can sit here and say i would never do that, its pretty inevitable someone will wanna play around and ill take the bait, lol

yelo04goat

iTrader: (11)

brake boosting from a roll works wonders.. just have to make sure you get the move..


i say build it for the track have the cam specced and the tune worked for good spool and then run it that way don't run extra parts that could ruin the turbo or motor.. I'm sure you won't have any trouble hurting feeling on the street even if it spools slow from a roll

1320

iTrader: (6)

zombies is a flapper, I should know, I put it on, like the rest of the car. I also run them on my dodge ram 3500 (twin compounds) hx40 and ht3b/26. And on a sand rail with a s475, and on the turbo van with a 5.3 and a .96 housing 72.

I like em.......I like the area under the curve. I did have seizing issues on my truck, but I just honed the shaft area, and lubed it a bit and its been ok. All have been in service for years now. I dont ussually build a system with out them in fact.

JAX04

iTrader: (17)

Are you using the SP valves?

1320

iTrader: (6)

I make my own.

JAX04

iTrader: (17)

Shoot me a pm if your interested in making me one.

trav-tech

iTrader: (1)

(1320) care to share any pics of these set up on some of your builds? Thanks