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Author Topic:   destroked 400
A&M Motorsports
Dirt Maniac

Total posts: 117
posted May 17, 2005 08:19 AM  
Building a 4.125 + bore, 3.350 stroke engine with Brodix 11x 225 intake runners. Will these heads be tooooo much with the short stroke?

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Artie Perilloux
A & M Motorsports

chomme
Dirt Freak

Total posts: 300
posted May 17, 2005 11:36 AM  
RPM,s are the plan. Although I am on somewhat of a budget I am piecing the short block together 1 quality piece at a time. For starters I have a bowtie block and will work from there.

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Artie Perilloux
A & M Motorsports

wfoondirt
Dirt Forum Champ
Total posts: 505
posted May 18, 2005 07:52 AM  
We are running a 4.125x3.25 11x headed motor right now in our l/m. Driver loves it on the slick, but we have to turn ~8800 to keep up with the big motors when its tacky. We ran basically the same motor in mods alot and really liked them. The most important thing is compression, ours is 16:1, otherwise you will have no torque whatsoever.

Personally if I only had one motor I would go with a few more cubic inches, something in the 380 range. Its alot better all around unless you race primarily slick tracks. We're using the little motor now because we race a slick highbank 3/8 and don't need huge amounts of torque. But we also have a big cube motor that we will run at bigger or hooked up tracks.

A&M Motorsports
Dirt Maniac

Total posts: 117
posted May 18, 2005 08:13 AM  
WFO, the compression has me the most worried about this bore and stroke. I don't know if I can stuff enough piston into the 11x heads to get to 16 to 1 compression. With 18 degree stuff no problem but I'm stuck with what I have. Is there a specific piston manufactured to the Brodix combustion chamber to help me in achieving the most compression?

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Artie Perilloux
A & M Motorsports

wfoondirt
Dirt Forum Champ
Total posts: 505
posted May 18, 2005 09:54 AM  
It took alot of work to get the compression up. The heads had to be angle milled and we had to use a cometic gasket. You have to make sure the pistons have 40/60 valve reliefs or you will run into piston to valve clearance issues.

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