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Thread: Yada yada, more dynos.

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Posts: 31-40 of 262
2009-09-15 02:14:50
Oh hell run them at 4bar! Still have plenty of injector left. I only ran 3bar on my setup, albeit at roughly sea level. I don't have logs for injector duty cycle, but I was told that I was at the upper threshold as well. Aren't the 740's at 3bar good for like 450whp?
2009-09-15 02:18:45
Okay, 87 percent duty cycle with 740's yields ~435whp at sea level. 740cc injectors are good to 500whp at 3bar, so you've got around 65whp to play with. I need to see what boost you're running again.


After looking at your boost level, I think you're only good for 25~27psi of boost before you run out of injector at your elevation. That of course will change with atmospheric conditions. I wouldn't run over 25psi at 3bar of fuel pressure, but that's just me.

You may find that with the 1.06 A/R housing that you'll be dangerously close to max inj. duty cycle.
2009-09-15 02:35:18
yikes. Injector duty is way up there then. But I am nowhere near 430whp even... something doesn't add up.

My maf voltage and injector duty both say i should be making a ton of power.
2009-09-15 03:26:06
740cc injectors are good for 550whp from what the chart says. at 4 bar they are good to 610whp or so.
2009-09-15 04:30:37
I just went with 1000cc inj. to make it easy
2009-09-15 04:39:45
Hmmm. Maybe there are still a lot of pumping losses from the high backpressure. I am not sure if it is the housing or not, but I am willing to fork out money for the .82 anyway just to test. I think that I should be putting out more power, and there is a gremlin in the system that is not allowing me to do it. I'm gonna find it though.

Bent/burnt valve, possible, but leakdown doesn't show anything is wrong. Very little blowby from the engine. Run all this summer and still can't see any oil in the catch can on the level indicator. It has steel wool in there so it should capture oil pretty good.

Compression, not amazing, but typical number for this elevation. Could be my tester too. My stock VE with 10.3:1 only had 175psi compression and made 170whp with stock everything. 10.3:1 compression. My old 9.3:1 only had 155-160psi iirc.

But the car runs rediculously hard. I took her out and beat her up real good at the dyno day. Had to break in the new gearstacks

With 4 people in the car it was faster than me by myself on 15psi. We're talkin 800+lbs of cargo

Andy put down a few runs. They were inconsistent ranging from 320whp to 380whp in his DE with stock cams, SC61, split-log manifold.

My engine just sucks. lol.
2009-09-15 07:41:01
could just be a low reading dyno
2009-09-15 07:55:11
Run it on e85 or meth/water injection and you will make the power. There is more benefits to these types on fuel on a standard ve head that just detonation resistance......
2009-09-15 12:42:02
Originally Posted by ashtonsser
740cc injectors are good for 550whp from what the chart says. at 4 bar they are good to 610whp or so.

What chart are YOU looking at?

740 cc = 500 WHP * Red
---------------------------------------------740 cc @ 4 bar = 580 WHP
2009-09-15 13:37:17
hmm maybe i was glancing at the 800cc ones, sorry bout that. Lol
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