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senior member
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Discussion Starter #1
i was thinking of bumping up my compression from @ 8.5:1 to 9:1 to get better off the line results. will i loose power on the top end beings as i will have less volume to pack with boost? boost will be run at @12,20,&@25psi+. might wanna run e85 or alcohol temporarilly for playtime. at what point does lowering compression help/when does it not? 35psi,nitro,?
 

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Some guy
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Final compression ratio=[(Boost/14.7)+1] x Compression Ratio

With those boost numbers you may run into some reliability problems.
 

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Or Seth, either one
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Paul,

In your current application, I don't think you would notice much, if any difference at all in the way it performs out of the hole.

Two reasons:
1) It's a jet and isn't loaded at the punch like a stick shift car or hard biting prop... It doesn't have to pull itself through the lower rpm range. You may knock a slight fraction of a fraction of a second off the time it takes to hit max rpm.

2) It's a turbo and not spooled at the hit either.

There may be ever so slight benefits to be had, but you'd be pushing your luck with your current set-up...

Any loss in volumetric efficiency would occur at/near peak torque rpm. After that, it becomes a cylinder filling game of how much you can get in while the valve's open less and less time per intake stroke. If everything is in proper tune and you're using the appropriate fuel for the boost level, the extra half point would bolster the entire torque curve, even the slight VE loss at peak TQ will show a gain.

If you want to really boogie. Sell the Banks system and piece together a blow through system with new turbos... you'll make more power with less boost, and a lot more with the same boost. Just say'n. Probably spool sooner too.

Been following your build thread and you continually inspire me with your tenacity. Keep it up Paul! :))THumbsUp:))THumbsUp
 

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If you want to really boogie. Sell the Banks system and piece together a blow through system with new turbos... you'll make more power with less boost, and a lot more with the same boost. Just say'n. Probably spool sooner too.

Been following your build thread and you continually inspire me with your tenacity. Keep it up Paul! :))THumbsUp:))THumbsUp
:))THumbsUp
 

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steelcomp was here
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Paul,

In your current application, I don't think you would notice much, if any difference at all in the way it performs out of the hole.

Two reasons:
1) It's a jet and isn't loaded at the punch like a stick shift car or hard biting prop... It doesn't have to pull itself through the lower rpm range. You may knock a slight fraction of a fraction of a second off the time it takes to hit max rpm.

2) It's a turbo and not spooled at the hit either.

There may be ever so slight benefits to be had, but you'd be pushing your luck with your current set-up...

Any loss in volumetric efficiency would occur at/near peak torque rpm. After that, it becomes a cylinder filling game of how much you can get in while the valve's open less and less time per intake stroke. If everything is in proper tune and you're using the appropriate fuel for the boost level, the extra half point would bolster the entire torque curve, even the slight VE loss at peak TQ will show a gain.

If you want to really boogie. Sell the Banks system and piece together a blow through system with new turbos... you'll make more power with less boost, and a lot more with the same boost. Just say'n. Probably spool sooner too.

Been following your build thread and you continually inspire me with your tenacity. Keep it up Paul! :))THumbsUp:))THumbsUp
Very well explained!:))THumbsUp
 

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Premium Member
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I don't know how big this thing is, but the idea of 20, 25 or 35 psi from a Banks setup is pretty lofty.
Pushing 25 lbs at that compression ratio on E85 is doable, if you are on your tune. My guess is you're not, or you wouldn't be on here asking.
if you can't thoroughly conquer the above on E85, forget nitro. That's like starting a new career as a dog trainer, and starting with adult wild wolves. You WILL get bit!!!!



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Nitro a very delicate operation. Requires bravery. Ranks right up there with letting a dry fart out with a bad case of diarrhea. While wearing an expensive pair of designer underwear.

In other words, I wouldn't want to try it. :shock:
 

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steelcomp was here
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I don't know how big this thing is, but the idea of 20, 25 or 35 psi from a Banks setup is pretty lofty.
Pushing 25 lbs at that compression ratio on E85 is doable, if you are on your tune. My guess is you're not, or you wouldn't be on here asking.
if you can't thoroughly conquer the above on E85, forget nitro. That's like starting a new career as a dog trainer, and starting with adult wild wolves. You WILL get bit!!!!
But you learn, really fast! :cool:
 

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Haulina29
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The big question is on a antiquated Banks system if you could make 25 pounds wich you cant what would the exhaust pressure be ? Were not talkin roots with zoomies .?
 

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mo balls than $cents$
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I see that someone finally paid attention to the formula I put up in post #2. (If it's even possible to make that much boost with that system?)
If you convert the system to blowthru and throw on some cheap ebay turbos.talk to stallion thats what he did to hass's old banks deal and it turned out to run badass
 

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mo balls than $cents$
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Lets look at this:
Turn it to blow thru instead of draw thru
diffrenet turbos from Ebay'
headers instead of logs

Mmmmmmm yeah, thats still a Banks deal:)sphss
You dont know wtf youre talking bout bob go kick a puppy or something
 

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You dont know wtf youre talking bout bob go kick a puppy or something
You're a day late. Happens when you are use to waiting for your turbo to spool. The fact that you arrived is all thats important.

Paul,

There may be ever so slight benefits to be had, but you'd be pushing your luck with your current set-up...
If you want to really boogie. Sell the Banks system and piece together a blow through system with new turbos... you'll make more power with less boost, and a lot more with the same boost. Just say'n. Probably spool sooner too.


100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3
 

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Lets look at this:
Turn it to blow thru instead of draw thru
diffrenet turbos from Ebay'
headers instead of logs

Mmmmmmm yeah, thats still a Banks deal:)sphss
Eric still used the Banks logs & risers & wastegate adapters that I had, just moved the carb to the intake manifold were it should have been in the first place, added a couple of small intercoolers over the valve covers and it ran great, much better than the original old banks deal.
 
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