Try these links out


http://www.kennebell.net/faq/faq-answers1.htm

and

http://www.motorsportsdigest.com/forced2.htm

 

thanks jw.
hmm...still kinda confusing. according to that second article your "effective" compression can be much higher than would normally be considered safe. since it is the first article i have seen that gives formula for this kind of thing i'll go with it for now. i have a friend witha few books on supercharging, and i'll begin hunting through them for some solid info.
according to the second article i should be able to build my motor for 9.5:1 compression and run 12lbs of boost on it for a total effective compression of 17.3:1 under full boost.

 

My impression is similar to the article, from what I have heard/ been told over the years. It seems to be pretty accurate, good luck with your blown 408. Later

 

Okay, all these ideas fine, but even with 600 HP you're not going to terrorize anything but the slowest of all sports cars. Nomatter how much power you put to the trans, your truck is still far too heavy to outrun any but the mildest of all Camaros. If you want to go fast, you need to design the entire vehicle around going fast. Power is not the only thing required to move the vehicle. Think about weight transfer, traction, and areodynamics. If you really think about those, then you'll realize how you're not going to go as fast as you think you should in that truck. An AOD trans will not support that kind of power unless built by someone who will charge you half your proposed budget to doso. You mention that you need an AOD because you need to do highway driving, but have you considered what kind of efficiency a blown 393 will get? I would honestly be suprised if you got more than 6-7.

I know this from experience: if you spend a great deal of money and time constructing a very powerful engine, then put it to the stock drivetrain, you will not go much faster. To go faster, you need a lower rear end gear, and a lot less wieght.

I'm am certianly not trying to shoot you down, but I'm trying to make sure you're being realistic about what you're trying to do. you can put 600 HP in that '91 F-150 and you will be stuck in the 14's until you blow the transmission up. A 14 second 1/4 mile is plenty fast to blow away all but the baddest of all the imports, and it will run a close chase to a stock Camaro. The moderator, Ratsmoker, has a 14-second truck, but it is much lighter than yours. If you really want to terrorize people, go pull an old fatfendered Ford (1950's-1960's) F-1 or F-100 and put your money into that. You'll have a light truck that can be as light and fast as you're willing to go. This month's Car Craft shows a '67 Chevy that runs a 9.30 @ 140 with his 10-71 blown mouse motor that puts 772 HP to the wheels on methanol.

It will be a cool project whatever you decide to do, but be realistic with you performance expectations. Personally, I think a C4 transmission with a Gear Vendors overdrive installed on it will be your best bet, since they have been proven to handle as much as 2,000 HP. The GV unit can split each gear into two, so you'll have 1, 1-high, 2, 2-high, 3, and 3-high (overdrive). Imagine a close ratio, hydraulically-shifted 6-speed. I think a naturally aspirated big block, or a small block with a good dose of laughing gas and some very low gear in a light vehicle will give you the ability to blow away anybody you really want to. TK

 

thanks tk. a lot of that has already been thought out without all the details.
i figure a c6 automatic with performance rebuild, and a ford 9" rear end with perhaps 3.75 gears. plus, i am planning on shifting some of the weight to the back of the truck (batteries, a good thick spray in bedliner and i already have a fiberglass hard tono cover). plus i was looking into some 16x10" wheels with good rubber for the rear end. i don't know how much suspension work is gonna be done, except for lowering the rear end some.
I know i'll have traction issues still, and mileage isn't really a concern since this will be a week-ender anyway. plus i'll be keeping the 2 stock gas tanks for 30+ gallons of gas.
the thing is i don't expect this truck to be a drag strip champion or anything, i mostly just want a scary sleeper.

 

Why not shave the gas doors, ditch the fuel tanks, and put a fuel cell in the rear center of the bed. Think about an E40D tranny, c6 with over drive and very strong with a decent rebuild. Don't be so quick to ditch the 8.8, its a strong rear axle, with some attention. later

 

hmm, well the fuel cell idea might happen a ways down the road when i get the bodywork done. it sounds pretty good.
my buddy is trying to get me to go with a Dana 60 or 70 rear for the full floating axles. i dunno. ill look into what can be done with the current rear-end to beef it up. my biggest concern was breaking axles.

 

Well the dana is strong as well. Good luck with your choice.