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Got the car tuned today


johnAWD

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;1912033']Allow me to elaborate on my previous "outrageously optimistic dyno" comment.

 

The ambient pressure in Colorado Springs is about 3 PSI less than at sea level (e.g. LA). Thus, 10 PSI boost in Colorado Springs injects as much air as 7 PSI boost would in LA and 7 PSI is approximately equal to the stock turbo's wastegate spring pressure. I'm quite confident that the stock turbo on a stock tune holds at least 7 PSI to redline. So a stock LGT in LA should be pushing at least as much air through its engine as the modified LGT running 10 PSI boost in Colorado Springs. So how does the one in Colorado Springs produce so much more power?

 

The fact that it flows a ton more air at the same psi as the stock turbo.....

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The fact that it flows a ton more air at the same psi as the stock turbo.....

 

Which on a flow bench and paper is true. Turbo flow charts show the max potential of a given turbo's airflow capability, it doesn't mean the engine it is strapped on can flow the air....

 

So, when directly comparing different turbo's on the same engine,(Engine being defined as longblock) only the charge air temp will be different between them. So yes, the turbo heating the air the least will make more power, but it won't be too big a difference. Unless you are pushing one of them completely off its map.

 

Now, where larger turbo's show their stuff is in holding the boost all the way til redline. And therefore flowing more air, at lower temps, and hence the big power delta's over stock turbo's, particluarly the smallish vf turbo's.

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Congratulations John, those are great numbers, I would love to take a spin in your lgt. Your clutch should last a while if you take care of it right, ie. no track days and no launching. If I were you I wouldn't take it to the track either, you don't have anything to prove and for the time being you have a reliable running lgt that will eat vettes for breakfast at altitude. Enjoy it!
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Don't forget that you greatly improve the engine's efficiency when you toss the restrictive factory exhaust housing. That alone is enough to make a lot more power at the same pressure.

 

When I finally get everything on my car I plan to start tuning at wastegate pressure and then work up from there. I know the HTA Green from FP won't let me down in the power department!

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Dyno #'s and correction factors aside....

 

What afr is the 91 tune dialed in for? This along with knowing the inj. size tells plenty about the potential power being made.

 

 

11.0:1 across the board.

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;1912033']Allow me to elaborate on my previous "outrageously optimistic dyno" comment.

 

The ambient pressure in Colorado Springs is about 3 PSI less than at sea level (e.g. LA). Thus, 10 PSI boost in Colorado Springs injects as much air as 7 PSI boost would in LA and 7 PSI is approximately equal to the stock turbo's wastegate spring pressure. I'm quite confident that the stock turbo on a stock tune holds at least 7 PSI to redline. So a stock LGT in LA should be pushing at least as much air through its engine as the modified LGT running 10 PSI boost in Colorado Springs. So how does the one in Colorado Springs produce so much more power?

 

 

Maybe this helps:

 

10 psi is the measure of resistance to the turbos wanting to push air into the engine. The whole breathing characteristic of the engine comes into play here.

 

The biggest difference in going from 10 psi on a VF40 to 10 psi on a larger turbo is the restriction of the turbo itself. The VF40's hotside will restrict the flow of air substantially more then the hotside of the larger turbo.

 

This explains (in part) why the larger turbo will make more power (and flow much more air) at the same psi/rpm as a smaller turbo.

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I just got back from doing a couple of back to back "dyno" runs with my accessport v2. 3rd gear pulls, from 3000 - 6950 rpm. Car weight upped from 3365 to 3425. Fairly flat road, did a run in each direction.

 

First run: 371.60 hp, 349.15 tq

2nd run: 368.35 hp, 347.20 tq

 

Probably a bit optimistic, but pretty much in line with the dyno results.

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And I think I'm done. For awhile, anyway. Added a turbo blanket and a new K&N this morning.

 

http://jsalmi.com/car/turboinstall/scaled.IMG_5373.jpg

 

http://jsalmi.com/car/turboinstall/scaled.IMG_5375.jpg

 

http://jsalmi.com/tmp/test/scaled.IMG_5374.jpg

 

http://jsalmi.com/tmp/test/scaled.IMG_5375.jpg

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How are you liking your ride after a week of being in the big boy club? Stock clutch doing alright or having any slipping issues?

 

Sorry to threadjack.

 

I'm also running a different setup .... am I a member of the big boy club tommypenguin??? :lol:

 

After running the car for a couple weeks I find that I'm taking it somewhat easy so I don't have clutch issues. Haven't had slipping issues but haven't been driving the car really hard. Yes, I'm driving it but not going nuts.

 

After the tune was completed the tuner wanted me to accelerate hard from a rolling start. Had some definite slip from 2nd to 3rd.

 

I will definitely need a clutch shortly.

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Sorry to threadjack.

 

After the tune was completed the tuner wanted me to accelerate hard from a rolling start. Had some definite slip from 2nd to 3rd.

 

I will definitely need a clutch shortly.

Easiest way to identify a slipping clutch is to throw it in 5th on the highway at low rpms then go WOT around peak torque.

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How are you liking your ride after a week of being in the big boy club? Stock clutch doing alright or having any slipping issues?

 

No issues, but no launches. I roll on in 2nd and run thru 4th once in awhile simply for the rush.

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Picked up a couple gallons of $20/gallon subaru coolant this morning from GO. I've got another very small coolant leak to fix, which will require me to drain it again. It's been strongly suggested that I use this liquid gold vs prestone.

 

We were at Parker Days last weekend. Was fun flexing a bit. :)

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Something about protecting the aluminum block vs a cast iron block. I pinged a local scooby pilot who's in sales at a scooby dealership. One of the better know mechanics in the area, who now works at said dealership, strongly suggested it.
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