head skiming/size headgasket/hks f-con!
04-07-2008, 08:45 PM
Post: #4
 
272 cams is tooooo vague... I'd recommend to do some research into Dynamic Compression Ratio.... The main reason you need a high static CR with long duration cams has EVERYTHING to do with dynamic compression ratio and at what point the intake valve closes.

std cr is 9.4 to 1 = TVIS/largeport based engines 10.3 to 1 is std for non TVIS/smallport Which one do you have?

ASSUMING...... (std cr 9.4) TRD .8mm will bump 9.4 to about 9.8. TRD .5mm gasket will bump static CR from 9.4 to about 10.1 You will NEED adjustable cam gears because the gap from crank to cams has shrunk, so the cams need to be adjusted accordingly

272 duration cams...... 1) DON'T produce very much vacuum...tough to tune on a MAP system, tougher still with an AFM system - assuming both mangement systems are stock 2) Peak hp for a "common" 272 comes in at about 8000-8300, std computer has a redline of 7500.

May I recommend.... selling your 272 duration cams and get either a 256, or 264 cam.... at least both will work within the std engine management parameters

SERIOUSLY look at stand alone engine management *IF* you plan on building.... there is 10hp minimum available with a good engine management system... even with all STOCK internals!!!

Dan -

You can |Sad .... OR you can ask for help!!!

OST Porting service - http://hachiroku.net/forums/showthread.php?t=19991
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Messages In This Thread
[] - Martin Bjerre - 04-07-2008, 05:28 PM
[] - Rossi - 04-07-2008, 08:18 PM
[] - oldeskewltoy - 04-07-2008 08:45 PM
[] - nick - 04-08-2008, 07:22 PM
[] - Ivan141 - 04-08-2008, 09:57 PM
[] - oldeskewltoy - 04-09-2008, 05:09 AM
[] - Ivan141 - 04-09-2008, 06:18 PM
[] - oldeskewltoy - 04-10-2008, 06:17 PM

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