josh4ku

iTrader: (10)

I am having a hard to deciding what to do, i was thinking 416 n/a build installed of boost for more reliability. But just can't see myself going without boost! This is where I'm at currently. My car currently has a 6.0L, ported 243 heads, ls6 intake. I am wanting to go with a pro charger. This will mainly be a street car. Not a DD. 3.73 gear s60 rear end with a magnum 6 speed. 91 octane with meth. I have narrowed it down to 2 different options:

Option A (cheaper option)
slap forged pistons and rods, and use the stock crank in the 6.0 and hit it with idk 8-12psi boost. I want to make at least 600 rwhp. reuse my current heads and intake. Custom martin smallwood cam.

Option B:

stroke the 6.0 into a 408 and hit it with 8-12psi boost and make 700+??? Reuse my current heads and intake for this also. custom martin smallwood cam.

Ive never driven a 6 speed pro charged car so don't really know how either one will act. My fear with the 6.0 is it not having enough low end torque, but it will be quite a bit cheaper. Help me decide! I only want to do this once. Car will probably see 5-8,000 miles per year.

gccasper04

iTrader: (4)

I've got a f1A 408. Makes 800 on 15# with a 6spd. Love driving it as it drives like a NA car when just putting and then when you mash on the gas and the fun begins

Blown06

iTrader: (32)

With a procharger.......the bigger the better.

lbm13186

iTrader: (4)

I went with a stock bore 364 with f1, meth, 243 heads and 12 lbs and I'm making 650bhp that's with the stock crank and forged everything else... Got plenty low end torque for the street. I had to decide as you did and I like it, gives me piece of mind having the block thicker and now I'm thinking about pulleying down and making around 18-20 lbs. trying to get a aster bracket to work to eliminate belt slip over 12lbs. I also have a ls1 intake and about to switch to a ls6

josh4ku

iTrader: (10)

Yeah I will probably be happier spending the extra money on the stroker

josh4ku

iTrader: (10)

That's good to hear! Deoends if that extra 3500 for short block is work the extra 100-150 hp!

conan

iTrader: (5)

If your budget can afford I would go 408ci. If not a 364ci in the 10-10.5 compression range will still have plenty of low end power. I have had a low compression 347ci and a now a 10.1:1 compression 383ci Procharged 6 speed street car. The higher compression made all the difference in all driving conditions out of boost. Car has all kinds of power again in the lower RPM's and then comes to life fast when the boost kicks in. For a Procharged street car I wouldn't consider running anything less than 10:1 again.

What do you have in the car as far as exhaust ?

josh4ku

iTrader: (10)

If I was running e85 or 110 I would look at 10:1 but with 91 and meth isn't that a little too risky??

Planning to run kooks 1 7/8 headers and kooks true duals.

Bob@BruteSpeed

iTrader: (16)

A lot of people has successfully done 9.5/1 with 91 octane and methanol. I'd go that route if you can't get 93 octane. Bob

josh4ku

iTrader: (10)

I have never seen 93 octane in kansas! I may just have to do that then. Bob what head unit do you recommend for a 408?

conan

iTrader: (5)

I'm on 10.1:1 compression with 91/meth. I have the car tuned on pump gas only and the meth comes on at 4 psi for some added safety. Its not part of my fueling. No knock or detonation, A/F is 11.5 until the meth comes on, then drops close to 11 in the higher rpm's.

Bob@BruteSpeed

iTrader: (16)

That's good to see! Are you using 100% methanol? Bob

conan

iTrader: (5)

Yes 100% Methanol.

It does suck you can't get higher octane at the pumps in the mid-west / west. I used to get 94 octane at the Sunoco's at the pumps when I lived in the Pittsburgh area.

Rise of the Phoenix

iTrader: (27)

Given the right cam and enough compression, you aren't going to have an issue with not enough low end torque/power on a 364ci D1SC setup.

josh4ku

iTrader: (10)

Well if 9.5- 10:1 will work. I may just put rods and Pistons in the 364 and use the stock crank.

roastin240

iTrader: (13)

Why not just slap the procharger on the current engine setup? Just dump meth in there for safety. You should be able to hit your 600whp on stock rotating assembly with 93/meth

Rise of the Phoenix

iTrader: (27)

If you're not trying to spend a ton of money, that's what I would do. The stock crank should be just fine at the power levels you're looking to make. My long term goal for my car is to add a D1SC. I'll probably try to keep all the stock internals though. I've seen it done a lot if you have a good tune, run good gas, and don't try and get too greedy.

josh4ku

iTrader: (10)

I only can get 91. Idk I'd just rather do it a little stronger the first time. i have to change the heads of I go that route . It's currently sitting at 10.7:1

josh4ku

iTrader: (10)

Probably would work fine. I have the money to do more. Just trying to figure out what the best all around setup will be and ultimately not regret in the future.

Rise of the Phoenix

iTrader: (27)

Then by all means drop in forged pistons and rods. Have you done the math yet to see how much more a 408 would be? Hell, if you're going to do that, why not do something like a 416ci setup? It's probably not much more than doing a 408ci.