New Member
May 21, 2013
Looking for some advice on the current build. Car is a 2000 Saleen S281-sc. Original goal was about 6-700whp with a kenne bell. New goal is about 750whp pump gas and 900whp e85. The build: 4.6 iron block .20 over, trickflow 44cc heads, mhs tfs stage 2.5 blower cams, kennebell 3.2lc, arp head studs, arp main studs and side bolts, eagle crankshaft stock stroke, manley h-beam rods, diamond dish pistons (compression ratio somewhere around 9.5 to 1 have to look through build sheet again), total seal rings, king main bearings, clevite rod bearings, billet oil pump gears, comp cams adjustable cam gears. The car has a t56 magnum with a built 8.8, with twin 525 return style fuel system. Car has 80lb injectors on it from original build, and will be getting upgraded once it's time for the E85. This build has been years in the making, being na for some time while saving for the kenne bell, and unfortunate life events have postponed it until now. Car will spend most of if not all of it's time on the street as it is a lower mile show car, and it will absolutely not be getting a roll cage, although it is getting upr upgraded upper and lower torque boxes to try and manage all those ft/lbs. Now my question is, what size headers would be suitable for the aforementioned goal of 900whp on e85, would the 1 5/8 that are on there now suffice or would it be worth investing in a bigger 1 3/4 or even 1 7/8 header. There's not much info out there regarding header size for the application. Also, does anyone have any experience with running the mhs 2.5 blower cams up to 7-7500, which will probably be the intended rpm range given the power goal. Also, what are you twin screw guys doing to keep IATs down? Any advice/info is appreciated, not too many guys building big hp twin screw 4.6 2v so we are kind of in uncharted territory here.
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Feb 3, 2011
The land of commies and socialists!
@99-04cobra4life welcome to the site.

I would call MHS about the cams.

1 5/8 headers seems a little small for what your planning.

As far as the heat goes run the largest heat exchanger you can.

Upgrade all the lines and fittings to 3/4 minimum. Make sure all the fittings don't have excessively small I.D.

Bypass the reservoir like a GT500. They pump KB supplies may also need to be upgraded.

If I am correct thanks to KB you can't really go past 3/4 lines due to the design. You can never flow more water than your smallest restriction allows.

I'd be very interested to see the transfer tubes for your intercooler brick. If they look like I suspect they do there's some serious gains to had there as well as at the brick itself.

Post some pic of it and I'll let you know if and how you can.
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