First off I'm new to the turbo world. I have a procharger P1SC and have just bought a used turbolocity single turbo setup kit. Shortly after buying it I have found out that it seems that the 2v engine that I have doesn't like single turbo's. The reason gave was because of suspected valve float, and that the kit would fall on its face way earlier than any other power adder out there. Is this true, or should I have nothing to worry about?

 

I always thought it was space limitations, but not 100% sure.

 

Pure and simple BS. What they don't love is the fact that you break the rods at very low hp levels.

 

My power falls off as well with my PTK kit. I've seen dyno graphs of the twin kits falling off as well, but the fall off doesn't seem to be as dramatic. And I can personally attest that it is NOT a dyno-loading issue for my problem was rearing it's ugly head at the track as well.

I've seen 2 2v single turbo stangs over 1000 RWHP so I know they can be made to work. I just need to figure it out.
I have a few theories and will hopefully have the problem corrected over the winter. First I have to get this C4 in.

 

the problems I have read about with these kits also include, not being able to produce very much power on an turbolocity kit, pretty much the kit has been nothing but trashed in any thread I have read.  I don't know what to do. I hope someone who has had experiences with this kit could post something on here.

 

Mine loves my single Where is you alls' power falling off at? Lemme guess 5200 on up? It probably isn't the kits fault, the stock intake and cams weren't exactly designed to pull to 8,000 rpm. Thier powerband is right around 5200, it's downhill from there.

Are you losing boost somewhere? If you aren't losing any boost then I wouldn't blame it on the kit.

You gotta make your own space, there is more room in front of a 97 GT engine than there is a 95 GT engine.

#ad

I 2nd that one. This is mine @ around 400 fwhp.

#ad

 

It's a BS myth that has been spread by people that don't haev a clue. There is nothing that will maek a twin set-up any stronger than a good single on a 2V car.

 

You need to remember that the valve springs are only rated at 60#'s from the factory for '99 up cars. Couple that with a few thousand street miles and you have some springs that aren't really up to the task of holding down exhaust backpressure.
It IS an issue with some cars/kits. I can speak from experience on that.
As far as the heads/cams/intake being restrictive, that's not the reason. I had a vortech on my car and that thing pulled till I let off(6300 rpm).
It seems like a few people on the internet have debated the issue and theorized but no one has posted up a fix. If/when I get it worked out I'll let you know.

 

So they are supposing that a single turbo will somhow have less backpressure against the exhaust valve?

 

I'm not exactly sure what you mean by this.
I don't know about everybody else but my thinking is going towards MORE backpressure.  I have yet to actually measure it.  I sold my tremec and I'm just about done with my c4 swap so my car hasn't been driveable in awhile.  The next thing on my project list is to measure actual exhaust pressure.  That data should be able to tell me if I'm going in the right direction.  Any help is appreciated. 8)

 

well thank God. I guess I will just take my procharger off and put on the turbo. I have a few more questions, should I be able to get a better time with my car turbo charged? I have ran a 12.00 1/4 time with a 1.89 60ft time at 115. Will I be able to go faster, my heads are being ported right now but I'm not sure that will matter now. I called procharger and they said with the P1SC I should be able to produce up to 800hp, but I don't believe it b/c the belt was slipping at only 12psi.

 

Do you remember me? I was at douglas the night you and itsav6 were over there, I was the one with the direct port nitrous kit on that 97 gt in the above post. I was also in adel the night you were runnin like 12.40's and Randall said you belt was slippin. You guys need to let me know about when yall are plannin on going back to the track, I am going to douglas this sunday you guys ought to come to.

 

I don't see how you are having problems @ 8 psi, I have 7-8 psi on my single kit and the power really doesn't fall off at all. BTW I have the 99 heads on my car. If you think the valve springs are the problem and you need a fix, call vt, comp, crower or basically any other company and order a set of valve springs. Do you think you may have too small of an exhaust housing on the turbo? That may build excessive exhaust pressure @ high rpms. Is there any way you can post up you dyno numbers? That would be better than discussing something that no one can see.

 

Are you getting the 8 psi from my sig?  I've ran more than that.  The more you run, the faster/sooner it falls off.  The valve spring manufacturer's you mention don't offer very stiff springs.  The stiffest out there is Endura Tech, rated at 112#'s on the seat w/PI heads.  But I believe the solution is going to be a little more than just swapping valve springs.  I really don't want to throw a bunch of theories around until I get some more hard data. 
And my turbo is a gt40 50 trim with a .94(or maybe .96) exhaust A/R.  Should be plenty big enough for a 281. And the turbo kit I have uses tubular headers with 1 5/8's primary's so they should flow pretty well.
My car also has 80,000 miles on it so I'm sure the springs don't have anywhere near the rated factory force anymore.  I'm not the only one with the problem, just do a search on modulardepot or modularpowerhouse. 
I have dyno sheets of 13psi but don't have a scanner.

thanks,
Jeremy

 

Properly sized single will work just fine on a 2V motor. We use PTK setups with our 4.6 customers....no problem and big power.

 

After thinking about it some, I think I am just going to sale this kit and fab one.

 

Yes I remember you, I have emailed you. If you will call me so I can ask you some questions about your setup.
My car is going through a major transformation and I just don't want to go the wrong route with it.

 

Wow, I haven't heard any of this before but I have been buried in my car. I have transmission problems right now so we stopped at 10psi and from 6-8 there was definately no power loss. I haven't dynoed it yet on 10 but it feels like it pulls all the way through and I'm running my car up to 6500 on the pulls too. I'll post numbers when I get them but I'm going to agree with the guy that said "Unless your losing boost, it's not the turbo kit". I do have built heads and a bullit intake with a huge throttle body and stage II cams and maybe that's the difference... I don't know. I do know my combo put up good numbers on low boost and eveytime I turn the boost up it loves it. That is a wierd problem you guys are having. Interested to hear the problem.