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Sure, what do you want to know?
Its a fairly straight forward setup with a gtx2863r and a holset hx50 with 67mm compressor wheel. 2x 44mm wastegates for the hp turbo and 1x 44mm for the lp turbo. The engine is nothing special. Just a stock bore 1.8 20vt, with forged rods and pistons 8.5:1CR Plus a crank girdle and pinned pulley. The head has the squish areas machined out and has been ported and polished. Upraited valve springs, inconel exhaust valves. Stock intake valves, followers and cams. And arp head studs.
I fabricated both the manifolds myself along with all the boost pipes. Fuel system is just 2200cc injectors on a modified stock fuel rail with 2x aem 400lph pumps. 1 feeding each side of the rail using an8 hose at 3bar base fuel pressure.
Boost control is as above with a manual controller on the hp and a 4 port mac on the lp. The ecu I'm using is a motorsport electronics ME442. I've only added a few extra sensors like flex fuel, EMP, EGT, fuel and oil pressure. I think that about covers the majority of it. But I'll more than happily answer any questions or grab more pics if you're interested
 

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I took the car to the dyno yesterday. We ran into a few issues, 2 of which are easily fixed and 1 which is really bugging me.
First issue, I need a proper FPR as the second pump over powers the FPR when it kicks in, Easy fix.

Second issue, spark blow out at high rpm. Most likely faulty coil sticks( tried different heat range plugs and different gaps along with increasing dwel with no luck) again a easy fix. I'll probably upgrade to some big external coils with HT leads.

Third issue, no matter how much boost we added after 29psi it made no extra power.
Intake air temperature throughout stayed at 86f even at 43psi so it's not running out of efficiency. EGT's stayed constant and total exhaust manifold pressure stays 1:1 with MAP so I can't see it being a exhaust restriction problem.
Adding ignition timing actually made less power so I'm thinking it went past mbt on that. It's running between 8 to 8.5:1 CR on e112 and knock monitored the whole time with zero signs of knock all day.
What I don't understand is that if the engine is getting fed 43psi and exhaust pressure is the same there it can't be lack of flow through the engine. So it should make alot more power. I feel like I'm missing somthing important here.
Any way, we capped boost at 29psi it made 430 at the crank. So it's on target to achieve what I want from it at 60psi. I just can't work out why it wont make more with adding an extra 14 psi in theory it should of brought it up to about 600


 

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Discussion Starter #1,603
Delaying the turn on point of the second pump can stretch the FPR capacity, if you don't need to activate it sooner for other reasons.

By that description it should have made more power. Is it possible the ignition just didn't have the power to fire it reliably at higher boost? You mention new/better coils, so this comes to mind first.
 

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That's a good point. The second one doesn't need to be on at all this power level so it could potentially be left off until just before fuel pressure starts to drop off. But I think I will still replace it with a higher flow regulator just to be on the safe side.

It is possible that the spark just isn't carrying enough energy to properly set off the ethanol. But it's really strange how the 43psi run followed the exact same power curve as the 29psi run, up to the point it blew out the spark about 1500rpm sooner.

I'm off to the track tomorrow and im borrowing a set of known good replacement stock coils to try. I'll see if that does anything with the issue and hopfully gather some helpful real world data logs
 

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Monk-E something is definitely wrong. Only 430 at the crank should be like 20 psi on that setup. I ran a 2 liter 16v and it made 500 at the wheels at only 26psi. You sure your cam timing is right? Did the pulley keyway sheer and the cam timing is off? What RPM you turning it to? Did you upgrade the valve springs?
 
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