2" Headers on a 347/F1C setup?
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2" Headers on a 347/F1C setup? I currently run 1 3/4" Long Tube Headers on my forged 347/F1C, pushing ~19psi. Would 2" LT's be too much on a 347, or would it work well, since it's on a F/I set-up making ~800+rwhp???
TIA
TIA
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It depends on your goals and application. We are learning that blower combo's need bigger exhaust than you would think. It is important to note this is based around all out drag racing applications. With bigger headers you may suffer a drop in power/tq in the lower rpm bands. If this is a street car you are probably fine with your 1 3/4". If it is for all out drag racing I would consider putting the 2" headers on.
I'm running a 410" motor with a gear driven F1C and we are going to build a set of 2 1/8" stepped to 2 1/4" with collector mufflers. For us our engine lives between 4500-8500 rpm so we were not concerned with what happens at 3000-3500 rpm.
Hope this helps and good luck!
I'm running a 410" motor with a gear driven F1C and we are going to build a set of 2 1/8" stepped to 2 1/4" with collector mufflers. For us our engine lives between 4500-8500 rpm so we were not concerned with what happens at 3000-3500 rpm.
Hope this helps and good luck!
Last edited by ericg69ss; Mar 22, 2011 at 05:30 PM.
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Thanks for the feedback guys. I've got 3:73's and a 3600 stall, so I would think that should keep the car pretty responsive down-low in case of any power/tq loss in the lower RPM's. I know not too many people are running 2" LT's w/ a 347, but there are quit a few running 1 7/8"...
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Thanks for the feedback guys. I've got 3:73's and a 3600 stall, so I would think that should keep the car pretty responsive down-low in case of any power/tq loss in the lower RPM's. I know not too many people are running 2" LT's w/ a 347, but there are quit a few running 1 7/8"...
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Launching!
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From: Elk Grove Village Il
I try to get out to the strip a few times a year, but the car is mainly a street toy. Just looking to make it more efficient. The converter is a PY3600, so it should be pretty tight and not slip. Looks like you're pushing a good amount of boost as well..got to love the F1C 
Thanks!
Thanks!
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I wouldn't waste my money on a 2" header unless your starting from scratch. The biggest bottle neck is the 3" mid-pipe section and 3" collector. Until they make a 3.5" collector I won't be changing anything.
BTW-the 2" requires some massaging if your running a aftermarket bellhousing.
BTW-the 2" requires some massaging if your running a aftermarket bellhousing.
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Launching!
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From: Elk Grove Village Il
I wouldn't waste my money on a 2" header unless your starting from scratch. The biggest bottle neck is the 3" mid-pipe section and 3" collector. Until they make a 3.5" collector I won't be changing anything.
BTW-the 2" requires some massaging if your running a aftermarket bellhousing.
BTW-the 2" requires some massaging if your running a aftermarket bellhousing.
I wouldn't waste my money on a 2" header unless your starting from scratch. The biggest bottle neck is the 3" mid-pipe section and 3" collector. Until they make a 3.5" collector I won't be changing anything.
BTW-the 2" requires some massaging if your running a aftermarket bellhousing.
BTW-the 2" requires some massaging if your running a aftermarket bellhousing.
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Launching!
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From: Elk Grove Village Il
Iron 346, ported 706 heads with cometics and ARP bolts, cog driven F2 with A2W. Sounds dumb, huh? Gonna start with a 77/54 pulley combo to help it survive. Sorry for the thread hijack.
Back on topic please.
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Should now within the next month or two, haven't got it running yet. It's a "I'm gonna get flamed combo on this site" but we'll see how it works. If it doesn't, I'll build another motor for it.
Iron 346, ported 706 heads with cometics and ARP bolts, cog driven F2 with A2W. Sounds dumb, huh? Gonna start with a 77/54 pulley combo to help it survive. Sorry for the thread hijack.
Back on topic please.
Iron 346, ported 706 heads with cometics and ARP bolts, cog driven F2 with A2W. Sounds dumb, huh? Gonna start with a 77/54 pulley combo to help it survive. Sorry for the thread hijack.
Back on topic please.
