Exhaust-2.5 or 3"
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Team Owner
Joined: Oct 2004
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From: altered state
St. Jude Donor '05
Exhaust-2.5 or 3"
I hope I'm not brutallized 'cause this one's not going in the vette.
6 in.rod 358, 10.5-1, Dart conquest heads (flow around 305cfm), SR 250/254 .050, .660/.670 lift on a 110, Team G angle milled w/ plenum work, Jesel 1.6, etc. Plan on using coated 1-3/4 Super comps and Flo's
Occasional street and strip use/weekend warrior. Plan on running pipes all the way back- 2.5 too restrictive, or am I in 3 inch only territory?
Occasional 7200 rpm blasts-3300 lb car, 4.11's, 97 T-56
Don't want to kill all torque, but don't want it choking. Whatchya think?
6 in.rod 358, 10.5-1, Dart conquest heads (flow around 305cfm), SR 250/254 .050, .660/.670 lift on a 110, Team G angle milled w/ plenum work, Jesel 1.6, etc. Plan on using coated 1-3/4 Super comps and Flo's
Occasional street and strip use/weekend warrior. Plan on running pipes all the way back- 2.5 too restrictive, or am I in 3 inch only territory?
Occasional 7200 rpm blasts-3300 lb car, 4.11's, 97 T-56
Don't want to kill all torque, but don't want it choking. Whatchya think?
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
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2.5 will carry you a long way..out to around 500 or so crank HP barely, but you have a pretty serious piece there. No way I wouldn't go ahead an put 3" on it if I was starting from scratch. It allows you growth room later and can actually be quieter if you use right mufflers.
JIM
JIM
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
If you have heads that actually flow 305cfm on a 355ci with a cam that big there is only one thing that motor is good for and that is revving, so you can forget about the torque loss thing, go with the 3 in. pipes and rev the crap out it 
Thread Starter
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
The heads, believe it or not flow some pretty good number lowers in the curve (better than a CNC AFR 195), Yet the ports have very little material removed. I spent a ton on these babies! I'll have to dig up the flow sheet and the cam card. It has very short seat timing; The ramps are slightly inverted. I wish I'd had an extra $500 at the time to dyno this pup as the #'s would tell me more. I'm sure its well over the 500 mark somwhere. I appreciate the feedback.
