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Discussion Starter #1
I am building a 468 bbc with the following specs and would like an estimate on the hp and tq:

468 ci
compression 10/1
merlin heads, oval port, 2.19"intake, 1.88" exhaust, 119 cc
stroke 4"
rod length 6.135"
Isky 280 megahydraulic cam, lift .565"
edelbrock airgap intake
holley 750 cfm carb, manuel secondaries
2 1/2" Patriot headers into 3" exhaust with Flowmaster 50's
hei ignition w curve kit

thanks a bunch for your replies.
jeff taylor
 

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I would estimate around 500 hp and 500 ft lbs. Below are a couple of motors to compare to. I think yours will be somewhere in between.

454
~8:1 compression
220 @.050 .500 lift hyd flat tappet cam
weiand stealth intake
"049" heads with 2.19 1.88 valves

made 419 hp @5100 RPM 473 ft lbs @ 4100 RPM
http://www.compcams.com/Community/Articles/Details.asp?ID=-1989283802

Although your heads will flow better, I think a set of 049's with the 2.19 valves would be close enough to make a comparason.

This next motor is one that a friend of mine had built

461
9.5:1
242 248 @.050 ~.600 lift hyd roller cam
cleaned up 049 heads with larger valves
victor jr intake port matched to heads

made 560 hp @6100 RPM 560 ft lbs with 20w50 oil

I think these heads would flow a little better than yours, and he has a larger hyd roller cam. Also, I dont know if you have already gotten the headers or not, but you may be able to get away with a little smaller primarys.

Adam
 

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I think that Firestone is giving you some good advice there,a 2 1/2 header is way too big.My bbc only has 1 7/8 inch tubes and it works pretty darned good,and it is a bit more on the radical side than yours,the big tubes could hurt your low end streetability and all round torque.
 

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Discussion Starter #4
thanks for the quick response guys. After seeing firestone's comment, I went back and checked the size of the header primary tubes and found that they were only 1 7/8 inches.

keep the replies coming.
thanks,
jt
 
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