360ATI

I will soon begain working on a 408 for my Procharged 00' R/T, and just wanted some insite from all you guys who have taken the 408 path. This is what I have so far..........................aluminum R/T heads "Ported", M-1 4BB "PortMatched", Mild Street cam (Not sure on the size yet, maybe around .480-.500 lift area), bigger throttle body, a much small blower pully (12-13PSI) & Copper head gaskets. I would like for the compression in the new motor to be around 8.5:1 so I can get away with the much higher boost level safely..... Any suggestions would be great.

rtspeeddemon

Well just finishing my build up of a 408 with a procharger.

I assume you have strengthened the bottom end... Crank, rods, pistons etc?

Cam is a little small but should work fine, you can certainly go bigger especially with more cubes now available.

Add a windage tray while you are at it and of course a new oil pump.

12-13 lbs is likely about the max our heads can withstand and still stay attached to the block due to the poor bolt pattern.
Copper head gaskets are not necessary but your choice. Felpro 1008's will handle the duty just fine.

K.J

bad360rt

Yup, I'm pushing around 12lbs or so on the Felpro's with MP bolts, no problems so far. I need to start saving my pennies and collecting parts for a forged stroker shortblock, and maybe a lil more portwork on my heads

360ATI

Bad360RT

Do you still have the stock bottom end . If so, I had no idea they could handle that kind of power.

RTSPEEDDEMON

What compression ratio & throttle body size did you go with on your setup, also who did you buy your kit from? Good stuff thanks for the help .

BigPurp

1st thing, don't waste your time with the aluminum mag heads, they are total and utter crap. If you want aluminum heads look into the indy 360-2 and run the 360-3 intake manifold with them.

Simpler solution is to stick with 2.02 r/t heads.

408 can handle a lot more cam than a 360, let that thing BREATHE. 212/218 .560.560 114 would be very very tame and work well with the blower.

58mm F&B or an accel/accufab 4bbl T/B

02sierraz71_5.3

iTrader: (2)

Im not familiar with a chrysler based 408 but that cam looks tiny I couldnt imagine you being able to even fill the cylinders with enough air seems like it would only hinder power production especially at higher rpms

rtspeeddemon

Bought the DFI etc through Damon Blumenstein
You can contact him at sales@db-performance-eng.com

TB is a F&B 52X55mm, compression is lowered to 8.5:1

360ATI

The reason for the smaller cam is due to the fact my truck is my daily driver, I agree a much biger cam would produce more power, but would greatly hender the drive ability of the truck . The largest cam I would go with would be .525 lift and most likely hang with a 55mm throttle body on the 4bb M-1.

bad360rt

I'm running a Mopar replacement shortblock now, ran lean and took out a couple of the stock pistons last Nov. BUT, the stock bottom end can handle quite a bit if you make sure you're getting enough fuel. I didn't have a wideband on the truck at the time (big mistake), I think I'd still be running the stock shortblock if I had known my a/f at the time. Live and learn. Anyone running boost should have a wideband on their truck, period. $500 for a wideband is a lot cheaper than a new shortblock. I made 452rwhp on the stock bottom end.

BigPurp

A nasty cam in a 360 will be pretty tame in a 408 so don't go too small. Also don't focus on lift that much, it has very little effect on the drivability compared to the duration and lsa. Mine is a daily driver as well, taken it on road trips etc. No issues what so ever. It's got a 214/224 .540/.560 on a 114 and isn't bad to drive around town/traffic at all. New cam will be quite a bit bigger and i'm not overly worried what so ever. I wouldn't run anything smaller than a 224/224 114 unless you plan on doing a bunch of towing and need all the low end torque possible.