What kind of valve springs to get to 900rwhp. Jpc uses a 3 inch up pipe. Edp uses a 2.5 up pipe and I think the crossover is to small. I did 790rwhp 826rwhp through an auto with a edp kit but that was the limit with trick flow stage 1. It is the bp issues that cause valve float.
EDP 7475 Results
- Thread starter Big Q
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What kind of valve springs to get to 900rwhp. Jpc uses a 3 inch up pipe. Edp uses a 2.5 up pipe and I think the crossover is to small. I did 790rwhp 826rwhp through an auto with a edp kit but that was the limit with trick flow stage 1. It is the bp issues that cause valve float.
I am the dyno shop owner that Big Q is working with. I am currently working with EDP to solve a couple of issues they are having.
So far is doesnt look like the hotside is an issues at all, but more on that later. If you dont know what to look for i could see someone jumping to the conclusion that the hotside is the issue.
So far is doesnt look like the hotside is an issues at all, but more on that later. If you dont know what to look for i could see someone jumping to the conclusion that the hotside is the issue.
Ok..... So what is it?
I will post back today once i get more testing done. I have enough to know whats up but i want to know exactly before i post anything.
Check out my facebook if you want 402 Dyno... My main goal is just to help the OP but if it helps everything else out i am glad. Just hang tight.
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Very interested as well.
it has to be something between the merge and the turbine, if the larger DP's aren't fixing it.
it has to be something between the merge and the turbine, if the larger DP's aren't fixing it.
From my findings it is not it the hotside or not the route of the problem.
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I honestly don't see how it couldn't be the hotside & intercooler...I am seeing a 6psi drop through the intercooler and when I tested backpressure I was well over 2.1...Interested to see your results/findings 402
care to elaborate?
You basically nailed it but haven't put two and two together yet.
Big Qs car has 8 pound spring in the wastegates. Bottom of the wastegates are referenced to manifold. This is to achieve 8 psi in the manifold regardless of what the turbo is making. What i found so far is just like you said a MAJOR pressure drop through the coldside. When i was commanding the wastegates to make 8 psi in the manifold at 6000 rpm i was seeing 13.5 psi at the turbo cover. A typical street turbo kit will be 2:1 backpressure to boost. That means at 6000 rpm i am roughly 27 psi back pressure at only 6000rpm with 8 psi in the manifold. I have not tested it higher yet but looking at the chart the drop will continue its trend and could possibly be making 15 psi to achieve 8 psi in the manifold. That means is its ONLY 2:1 ratio there is 30 psi of backpressure if not more... NO stock valve springs will support that without losing control and floating.
Once we see 8psi in the manifold and 8-9 psi at the cover the backpressure will only be 16 psi IF that. Then this car/kit will be making power and wont see the backpressure issues or at least not on a stock engine or until some serious power levels.
This is the dyno chart. Second from the bottom in black is manifold, Bottom is in red...
Take that red line and at least double it, that is the current backpressure in the system assuming it's only a 2:1 backpressure to boost.
https://flic.kr/p/xtUmYy
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I am wanking the front clip now and going to confirm its not the bov or anything else.
When i talked to EDP their intercoolers are of the cheap kind, so if i confirm this is the problem i hope edp listens and fixes their kits. If not please expect a BELL direct replacement from me.
When i talked to EDP their intercoolers are of the cheap kind, so if i confirm this is the problem i hope edp listens and fixes their kits. If not please expect a BELL direct replacement from me.
Here is my graphs I'm making 11psi on the manifold & seeing 17psi at the turbo...also saw 23psi in the hot side between the up-pipe & the y/merge section. 9.5:1 aluminator that comes w/ the boss valve springs (I know they are not much better than stock) the 721 pull was with an air to water intercooler from an f350 w/ couple bags of ice in it. Pressure dropped but it still hit a wall at 6k which leads me to believe that the intercooler is junk & the hot side is restrictive.
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Fix the pressure drop, get that turbo making 12 psi to achieve 11 psi in the manifold and your backpressure will drop dramatically and you wont think the hotside is restrictive.. Nothing there points to a restrictive hotside
so intercooler looking like the issue.
Interesting...
easier fix than hotside i suppose.
Interesting...
easier fix than hotside i suppose.
402, what do you think of the hotside? any modifications needed? or you think it's a good standard?
Not yet anyway. Once i get this car doing what i want, i will determine if the hotside even needs to be looked at. Personally i love the hotside on a street setup.
interested to see if something like this could fix all the issues.
http://www.treadstoneperformance.com/product.phtml?p=69394&cat_key=63&prodname=TR1245-28+1200hp
http://www.treadstoneperformance.com/product.phtml?p=69394&cat_key=63&prodname=TR1245-28+1200hp
Obviously another china intercooler but treadstone is probably the highest quality china one made....
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