10.67:1 on boost too much??

Badaz01

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As stated in the title I’m looking at running a 10.67:1 compression ratio on my 2001 cobra with stock heads a D1sc procharger and upgraded 3 core intercooler with 80lb injectors. Cams are stock as well. I am gonna have a 93 octane tune as well as an e85 tune. Is 10.67:1 compression ok for this set up on either fuel pretty sure e85 is ok not sure about 93 octane. I only plan to run Max 12psi of boost.
 

01yellercobra

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If the 93 is for emergency only you'll be fine. I wouldn't run that compression full time on 93.

And aren't you running a D1. Spin it to 17psi at least. World of difference in how that blower will act.
 

Badaz01

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If the 93 is for emergency only you'll be fine. I wouldn't run that compression full time on 93.

And aren't you running a D1. Spin it to 17psi at least. World of difference in how that blower will act.
I would like to run 93 for fall/winter storage. If for some reason e85 would become non existent could I run 93 with torco with the same results of e85.
 

MG0h3

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Not sure how long your car sits but just throw some stabil in it.

I’ve been on E85 non stop for 3 yrs or so. Car sits for a few months at a time in the summer. Couple yrs it got started once after 3 months than sat another 3 months. No issue.


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Badaz01

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Not sure how long your car sits but just throw some stabil in it.

I’ve been on E85 non stop for 3 yrs or so. Car sits for a few months at a time in the summer. Couple yrs it got started once after 3 months than sat another 3 months. No issue.


Sent from my iPhone using svtperformance.com
That’s cool my car sits in the winter where I live in southwest pa probably about 3-4 months. I’m having a dual in tank pump return style fuel system installed as well with the compatible parts for e85. Is there a special type of stabil formula for e85 or is it just good old stabil.
 

Badaz01

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I saw the new coyote motors specs today 12:1 wow and they run those on boost and pump 93. Don’t think I’ll have issues with 10.67:1.
 

Black02GT

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I saw the new coyote motors specs today 12:1 wow and they run those on boost and pump 93. Don’t think I’ll have issues with 10.67:1.

Variable valve timing can play a huge roll in dynamic compression. Can't compare 5.0s with 4.6s. On that note I run the compression OP mentioned +- (pretty much what works out for Cobra heads and flat tops with stock head gaskets). At 20 psi from a TVS so a Procharger would be a little less stress. I think yoh can do it on e85. Might have to chill on the timing on 93 but at 12psi I don't see a problem really.

Edit: Just realized 01 not 03-04. Stock rotating assembly?
 

Badaz01

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Variable valve timing can play a huge roll in dynamic compression. Can't compare 5.0s with 4.6s. On that note I run the compression OP mentioned +- (pretty much what works out for Cobra heads and flat tops with stock head gaskets). At 20 psi from a TVS so a Procharger would be a little less stress. I think yoh can do it on e85. Might have to chill on the timing on 93 but at 12psi I don't see a problem really.

Edit: Just realized 01 not 03-04. Stock rotating assembly?
Yes stock rotating assembly but it is forged Kellogg crank so that’s good to go also having Manley rods and the flat top pistons are Manley as well.
 

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