3V compression,boost and RPMs

Heaten m90

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On E85 with 7LBS of boost what would be needed to run 12+/1 CR while spining up to 7.5K RPMs. I'm thinking some beehive Springs, Dimond flat top pistons, manly rods and a good balancer with a stock crank stock aluminum block would work out just fine..... any thoughts?
 

Department Of Boost

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On E85 with 7LBS of boost what would be needed to run 12+/1 CR while spining up to 7.5K RPMs. I'm thinking some beehive Springs, Dimond flat top pistons, manly rods and a good balancer with a stock crank stock aluminum block would work out just fine..... any thoughts?

I don't think you can get over 11:1 with flat tops? Someone correct me if I'm wrong here.

Otherwise it all sounds good to me.
 

Heaten m90

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I haven't seen anything higher than 11:1 for sale on any website. How much wiggle room is there with deck height and head gasket selection?
 

drive_55_not

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I haven't seen anything higher than 11:1 for sale on any website. How much wiggle room is there with deck height and head gasket selection?


You'll need a custom piston with a DOME if you want more than 11:1.

I used Diamond flat top pistons ,, listed as .65cc dish on my current build using the 52.25cc measured average head volume, 3.562 bore, .030 compressed gasket, 3.63 gasket bore and .007 deck the calculated CR is 10.78:1.




.
 

05stroker

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Or mill the heads and or decks. With the deck height at .008 and a 48cc CC 12.0:1 is achievable. Thats what mine was with flat tops.
 

BruceH

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I haven't seen anything higher than 11:1 for sale on any website. How much wiggle room is there with deck height and head gasket selection?

If you use the FRPP heads with a small combustion chamber it's possible to go over 11:1 with flattops but it's not really going to make much difference imo.

A more capable supercharger will bring far more power than the compression ratio difference of 11:1 to a little higher.

Not sure what your plans are but that's where I'd go after putting forged rods and pistons in the car. Something capable of more boost with lower iats.

There are several compression ratio calculators available online. Here is a link to several performance related calculators:

http://www.wallaceracing.com/Calculators.htm
 

Heaten m90

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I completely understand your logic and I'm thankful of you trying to point me in the right direction. But I'd rather run a nitro/meth mix than get rid of my precious little m90 and the song she's been singing to me for almost 10 years now

with what I payed for the car and the money I got into it. I should be driving 1000WHP super snake lol
 

46addict

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I used Diamond flat top pistons ,, listed as .65cc dish on my current build using the 52.25cc measured average head volume, 3.562 bore, .030 compressed gasket, 3.63 gasket bore and .007 deck the calculated CR is 10.78:1.
Does Diamond make pistons in 3.56" diameter?
 

eighty6gt

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Use a stock 5.0 engine instead! 2015-2017 F150 - I think next year will be DI and that will be another nut to crack. I guess you'll need a TVS and a DOB manifold.
 

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