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Thread: Yada yada, more dynos.

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Posts: 71-80 of 262
2009-09-16 15:19:03
#71
Originally Posted by GT2871RBLUBIRD
well a base map is just that though, a platform to tune off of, if this car is running off a base map or i misread, i really feel the base map is your power problem.


Last I checked he was running a real time or one of those not a standalone
2009-09-16 15:59:44
#72
Originally Posted by DDSC
ok i can tell you there is a restriction. All ve's have it. It cost about $2-$3.5k aud to fix depending on how far you want to go.

As i said earlier, for a STANDARD ve head it will respond quite well to e85 or meth injection. This is true for a N/A set up, but more so for turbo. This extra power has NOTHING to do with the detonation resistance of these fuels. To give Another hint, there is a reason the n1 heads use smaller valves on the ex side...

Also, bigger cams and so forth NEED to be tuned whatever the engine! if you are running the same tune and expect big gains from a cams swap.....think again.


So, you're saying high compression with E85 is what's needed for VE heads...is that the restriction you're talking about?
2009-09-16 16:25:22
#73
Originally Posted by Coheed
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.


There you go that's your problem since day one there was a problem with your motor... A very healthy Stock SR20VE will give betwen 225-240 psi with everything sealing correctly. I have seen a VE-T with 8.5:1 wisecos measure 200 psi after changing a head with bent valve or valves not sealling and with that same head it was giving betwen 150-165 psi of compression. This problem was causing a loss of almost 80 whp proved by my friend
This means there its something wrong with your motor ... I have seen VE's with 3% leak down and still had bent valves those dam valves are very weak specially the exhaust ones... its just someting you should take into consideration...
2009-09-16 16:46:11
#74
Originally Posted by Scrildo
Last I checked he was running a real time or one of those not a standalone


He has a JWT ecu actually.
2009-09-16 19:13:05
#75
His motor could be a problem but im still doubtfull. My motor from the getgo had problems due to 3 starts with no oil pressure. Talkign 10-15 second starts each time with some reving to about 3k. Found out because of a spacer design misunderstanding the oil pump was damaged during tightening of the crank bolt. Needless to say the damage was done to the chrome rings. Found flakes of chrome rings when i pulled the pan off to replace the oil pump before the built motor even went anywhere.

Well lets just say that after that from day one my compression numers after breaking were as follows: 150, 150, 145, 150. Number 3 obviously took some brunt of the damage. But my motor runs absolutely strong as hell. Maybe not as strong as it could with healthy sealing rings but it more affects the idle and the idle only. I do get a tad bit of blowbye but nothing to worry about. I think the rings are slowly breaking in though because each time i beat on it and the more miles i put on it the better it seems to run.

I havent done a compression check since the very beginning but i may soon just to see if the rings are seating in more over time.

Again i dont see me gaining much hp by having say 175-180 psi of compression that the det's have when nice and healthy. But i wouldnt rule it out especially with leaky valves if that be the case.

The difference from leaky valves to improper sealing rings is the fact under boost the rings are pushed against the walls and during combustion helping seal more than while say at idle and out of boost. While a leaky valve is just that leaking all the time. So Payu you could be right my friend. Cant be ruled out.

I will say that even with my low compression my motor doesnt smoke a bit or burn a bit of oil at least not anymore since rebuilding the turbo, lol.
2009-09-16 19:22:10
#76
Originally Posted by Vadim
He has a JWT ecu actually.


with the jwt you pay for rechipping or reflashing the ecu with different tunes with your setup in mind no? that is too vauge and general, if you dont have a way to go into the ecu itsself and change the iginiton maping and fuel maping on the fly to suit your setup then i would definitly say you are probably losing 30-50whp maybe even more torque, those are nice ecu upgrades from stock as they optimize sertain things ect. but you really need a realtime or stand alone to fully utilize your setup, those kinda ''tuned'' ecu's are to general. now if im wrong and you can go into the ecu then stratch what i said.

but i definitly think your power is off if you are running a ''tuned'' chipped ecu.
aside from if you dont have anyother mechanical problems.

also alot of the times the dyno readings arent 100% correct so its possible you are making 420whp, but the dyno reading is just xx% lower
2009-09-17 00:05:52
#77
I totally agree its crazy what a good tune can do to these motors. Your running a vet setup with a det tune. I know you said people made good power with it but everything is totally different from car to car. Where you live also has an effect so I would see what a good tune can do for you and go from there.
2009-09-17 01:27:10
#78
Originally Posted by ashtonsser
His motor could be a problem but im still doubtfull. My motor from the getgo had problems due to 3 starts with no oil pressure. Talkign 10-15 second starts each time with some reving to about 3k. Found out because of a spacer design misunderstanding the oil pump was damaged during tightening of the crank bolt. Needless to say the damage was done to the chrome rings. Found flakes of chrome rings when i pulled the pan off to replace the oil pump before the built motor even went anywhere.

Well lets just say that after that from day one my compression numers after breaking were as follows: 150, 150, 145, 150. Number 3 obviously took some brunt of the damage. But my motor runs absolutely strong as hell. Maybe not as strong as it could with healthy sealing rings but it more affects the idle and the idle only. I do get a tad bit of blowbye but nothing to worry about. I think the rings are slowly breaking in though because each time i beat on it and the more miles i put on it the better it seems to run.

I havent done a compression check since the very beginning but i may soon just to see if the rings are seating in more over time.

Again i dont see me gaining much hp by having say 175-180 psi of compression that the det's have when nice and healthy. But i wouldnt rule it out especially with leaky valves if that be the case.

The difference from leaky valves to improper sealing rings is the fact under boost the rings are pushed against the walls and during combustion helping seal more than while say at idle and out of boost. While a leaky valve is just that leaking all the time. So Payu you could be right my friend. Cant be ruled out.

I will say that even with my low compression my motor doesnt smoke a bit or burn a bit of oil at least not anymore since rebuilding the turbo, lol.


exactly, my compression is low... compared to sea level cars. The 2psi less ambient pressure makes a difference in overall compression numbers. Maybe it isn't huge, but it is still a difference.

All I know is I don't burn any oil, the motor sounds and runs great. Hmmm. I am going to do some changes here for my birthday and get her back on the dyno.

I have thought about building another motor, but this motor is the strongest runner I've had. I used to have higher compression pistons in there, but it made a lot less power. The VET cams seemed to make the biggest difference in power. They really woke the car up with the log manifold.

But even if there was bent valves all the way around... why would the car only gain 4whp when the intake cam switches? This is peak power too, not just a small jump when the cam switches. There is literally a completely neglible difference in power when the intake switches over with the VE cams. VET cams still make a big difference when the intake switches. You can actually FEEL the intake cam switchover on the VET cams, but you can't feel ish when the VE intake cam switches. It seems absolutely pointless why it wouldn't flow better unless there was excessive backpressure or something.

Anyone have any ideas why the VE intake cam doesn't do anything?
2009-09-17 01:35:39
#79
Just hypothesizing with the VE cams... if you're not switching the exhaust cam at the same time as the inlet cam, then the exhaust cam's puny low lobe could be the restriction.

I'd really like to see what differences you get out of switching the cams simultaneously, hell even try switching the exhaust first to see what happens.


Do you have an idea of what kind of differences in compression #'s people see at your altitude compared to sea level?
2009-09-17 01:41:27
#80
I actually had the exhaust switch at 3700rpm with the VE cams. So when the intake would switch at 6000rpm there was little to no change in power. There may have been a very slight change in power when changing just the intake cam, and leaving the ex off. But who wants to do that?

Usually there is about 10psi difference from here and sea level, but it depends on the gauge you use too. My gauge I know reads lower than some others. My old DET only had about 145psi on all 4 and it made 330-340whp with the disco on 17psi.
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