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High Comp And E85

Simon-S14
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JustinP Mentor

JustinP

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Sounds good! I wish I had gone a bit higher on my build (9:1) as I will be using WMI with some safely measures just in case there is a failure of the system.

You could go really crazy and try and implement a DIY direct injection system to assist! Copy the BMW N54/55 design :) ) Would love to see that one day on an RB.

What are peoples thoughts on building a high comp motor with custom pistons with say 11:1 ratios or around that then running turbo and e85?

51NNA Community Regular

51NNA

Posted
Posted

Need more power Simon? Or just building a backup engine, nothing's impossible but you'll need a big budget, personally I wouldn't go higher then 10:1 but if you could pull off 11:1 it would be epic. The tune would have to be perfect and same with the build there's no room for error with that much comp, fuel would need to be under strict monitoring also.

GTScotT Grand Master

GTScotT

Posted
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Ive found that some of my +T setups have been sensitive to turbo choice. IE with an SR+T I found I could max a T28 on 9.5:1 and smash the performance of the equivilent DET 8.5:1, however moving to a TD05H 18G saw it was a lot harder to get the very most out of it.

In all cases ive experienced the cars have a lot more midrange with the added 1:1

I did however set sail to fail on my 10:1 setup, and am hoping to fix that soon.

51NNA Community Regular

51NNA

Posted
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I know this would be abit to extreme for you're application but have you considered a composite turbo setup? ie little turbo blowing into a bigger turbo so there's boost throughout the rev range? Ive had great success with this on duramax's but its been a HUGE budget involved. Considering though you have easy access to custom metal fabricators this wouldn't be such a challenge. Food for thought.

GTScotT Grand Master

GTScotT

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R u sure its smaller man? Im pretty sure the area across the firewall is the same but theres more room between the strut towers (i could be wrong). Its definitely shorter though.

Imagine rocking up to ANY event with a compound turbo setup, LOL

Simon-S14 Grand Master

Simon-S14

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dont want to be shaving the head that much to increase compression... you'll reduce the cumbustion chamber size.

need custom pistons with a higher crown height.

Would love to build a stroker RB28 with 10.5 - 11:1 CR balanced within a micron of its life to allow it to rev, Nitto spline drive pump to keep it lubricated. would be fairly nuts i would thing

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