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Jul 27, 2008 | 12:19 AM

HighdefJoe

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last header question

The 331 I'm putting in my 86 2wd has ported and milled GT40 iron heads, 1.6 Crane rockers, and a stage 1 Trickflow cam with .499"/.510" lift. The headers I was going to order were the Flowtech 12502flt, (the Hooker 6907hkr's are back ordered until late august).. anyway, do you think it'd be a huge power loss if I stepped down from the mustang 1 5/8" BBK longtubes
to the 1.5" truck headers? Are there 1-5/8" truck longtubes that aren't over $350?

Jul 27, 2008 | 12:53 PM

Franklin2

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From: Virginia

What transmission and rearend gears are you going to run? And if an automatic, will you have a stall convertor? If you never turn the higher rpms, then the larger header size won't matter.

Jul 27, 2008 | 03:51 PM

HighdefJoe

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The transmission is a 4spd OD manual. I'm probably going to need to find a 5sp ZF tranny after the motor swap. As for gearing, I have no idea what the truck has now. If I feel it to weak, I'll gear it later. Either way, I won't be revving too high anyway. It's my daily driver. When the engine was in the mustang, I would race it all the time but I just want a good motor for the truck while I build the monster for the mustang

Jul 27, 2008 | 10:23 PM

Franklin2

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From: Virginia

I would think the smaller headers would be ok. I would not go too wild with this motor if you are going to keep the rpms low. A truck is heavier than a mustang, so a high strung high revving engine is not going to work very well in the heavier truck unless you change the gearing. You will know right away if you are out of the powerband when in OD because the engine will not have hardly any power down in the low rpms.

Jul 28, 2008 | 08:00 AM

HighdefJoe

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Thanks Franklin. I'll let you know how it ends up when i finish it!

Jul 28, 2008 | 11:03 AM

nflfreak43

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From: La Vergne, TN

i want to see a video of this truck in action when your done this truck sounds like it will GET UP AND GO!! at least you wont have to worry about if you have power when you need it