Big port head flow tuning

[oldeskewltoy]

Diskovod Wrote:Yeah, man! Thanks for points!

I'm thinking about removing these boundaries also as there are no ones on Formula Atlantic heads...

and then slice some mms from the bottom of the head to have 11:1 compression...

When those areas you marked are removed, the term is commonly called "de-shrouding". When removed it is easier to run addition compression, because these high spots get hot, and can cause pre-ignition. The negatives is removing enough, and yet not "hogging" the chamber out... each particle you remove from the chamber DECREASES your compression! It is advised to get the chambers measured accurately *IF* you decide to mess inside the combustion chambers, that way you can make each chamber the same volume, therfore providing equal performance

As a comparison to your Atlantic head, here is my street prepared head....




I did my chamber work based on the TRD N2 engines (a bit closer to your street performance type)




Oh... you'll need one of these to measure chambers...

[Diskovod]

oldeskewltoy Wrote:

Diskovod Wrote:Yeah, man! Thanks for points!

I'm thinking about removing these boundaries also as there are no ones on Formula Atlantic heads...

and then slice some mms from the bottom of the head to have 11:1 compression...

When those areas you marked are removed, the term is commonly called "de-shrouding". When removed it is easier to run addition compression, because these high spots get hot, and can cause pre-ignition. The negatives is removing enough, and yet not "hogging" the chamber out... each particle you remove from the chamber DECREASES your compression! It is advised to get the chambers measured accurately *IF* you decide to mess inside the combustion chambers, that way you can make each chamber the same volume, therfore providing equal performance

As a comparison to your Atlantic head, here is my street prepared head....




I did my chamber work based on the TRD N2 engines (a bit closer to your street performance type)




Oh... you'll need one of these to measure chambers...

Sure, man!

"each particle you remove from the chamber DECREASES your compression!"
Yep, I know that, I'm gonna shave the head anyway.

Yeah, I'll need to measure them... that's not hard, but it take a little time to make that fluid based measuring stuff

Also I suddenly found through Club4AG your files on the Box with TRD N2 manuals! Thanks for sharing!

I'm going to pull out my engine soon, will be showing pics of progress and be likely to get some more advices. Anyway thanks for your posts!

P.S. Do you know what was the compression ratio for Formula Atlantic?

[oldeskewltoy]

Diskovod Wrote:P.S. Do you know what was the compression ratio for Formula Atlantic?

http://www.geocities.com/motorcity/7177/...specs.html - not sure how accurate....