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Adding a blower to a 13:1 engine

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Big Rhino:
I am getting ready to add a 10:71 and alcohol injection to my 412 sbc.  Dart block, iron eagle heads and currently running 13:1 compression.  Is this too much?  Do I really need to drop down to a lower static compression?  This will be my "trial by fire" as this is my first time dealing with a blown engine.  Are mls gaskets OK with this set-up?
Thanks for any input!

Frontenginedragsters:
In my opinion:
 13 to 1 static compression is too high.
You will find with that much compression that it will be VERY timing / tuning sensitive.
Its like trying to walk on a fence. You can do it but you have to be on your game.
11 to 1 was always considered a safer place to start. 8)
MLS gaskets have no place on a supercharged alcohol engine.
SCE copper is the best way to go.
My opinion: Matt

ricardo1967:
Matt, I agree with you, but... can you please elaborate this part?


--- Quote from: Frontenginedragsters on September 30, 2013, 05:29:34 PM ---...MLS gaskets have no place on a supercharged alcohol engine.
SCE copper is the best way to go.
--- End quote ---

Big Rhino:
Many thanks Matt,
This is the kind of info I'm looking for.  I want to do it right the FIRST time.  11:1 it is, and I guess I'd better go swap out my gaskets!!  Thanks again,
Tom

GlennLever:
10/71 seems like a lot of blower, not sure you need that much or you will have to under-drive it a lot. Is it stripped?

Currently running a 8/71 on a 13.5 to 1 on my blown engine.

Not by choice, I took a normally aspirated engine and added a blower to get to the 8.5 index I was looking for on the normally aspirated engine.

I did not need all that much, best run as the normally aspirated engine was 8.59.

At Bowling Green this past weekend I ran it at 8.03+ (I really need to pull that time slip back out).

The input I have received is that initial compression ratio is not as important as the finial compression ratio. I have had tuning issues as stated by Matt above.

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