Ok, got around 34,000 miles on the truck and will be upgrading the motor from the 4.8L I already have. The truck is an '04 RCSB 2wd with a 5 speed and 3.73 gears. I am contemplating buying a LQ9 and camming it and leaving the entire rest of it alone. But will I be happy? I need a 13 second flat truck. I want to be NA with no nitrous or blowers so that's out of the question. Anything I've ever had that's been fast throughout my life has had more than 400 cubic inches, I don't know if I'm going to be entirely convinced that a 364 cubic inch motor will please my palatte for torque. I have desktop dyno 2000 and put together a realistic naturally aspirated 402 motor with a Z06 cam and small tube headers. It produced the flattest and most pleasant powerband yet with that cam. For heads I am considering a set of mildly ported 317 casting heads to keep port volume within reason and keep intake and exhaust pulse velocity high. This motor is expected to produce flat torque from off idle to 5500 RPM's, I will take it up to 6,000 on ocassion but there shouldn't be a reason to if this motor is built strong enough. Now keep in mind I'm trying to build outside the box here and not make a big lopey, shakey, non-operable at low speed truck. This is a daily driver and needs to knock down 17 MPG or better. Now, an 11:1 comp 402 with 317 heads (got the flow numbers from richard@WCCH) desktop dyno is producing some pretty stout numbers. SEE BELOW. The only factor is, can a motor like this be built for around $4,000 or less? What does the typical 402 shortblock go for? Heads seem cheap and I can swap most of my valvetrain over from my existing 4.8. What have you guys spent that built your own? A truck like this should run 13's no problem and leave room for more down the road if I should so desire.

 

have the same program... love it... one thing ive noticed in your picture though, is youve got yourself setup for a 402... not a 408...

bore = 4.030 = 408

prolly wont change your numbers much, but just somethin i noticed...

 

IMO, you can easily get a 13 second flat truck with a H/C 6.0 and save a ton of money.

 

[QUOTE=hirdlej]The only factor is, can a motor like this be built for around $4,000 or less? What does the typical 402 shortblock go for? Heads seem cheap and I can swap most of my valvetrain over from my existing 4.8. What have you guys spent that built your own? A truck like this should run 13's no problem and leave room for more down the road if I should so desire.QUOTE]

I'm actually gonna do a similar truck pretty soon, got a rcsb lined up that i'm gonna do a cammed 6.0, and eventually gonna do a 408. Just wanted to post to make sure if anyone has valuable info i would get it, hope you don't mind. I know that a lot of guys are doin really well with 408's, probably is still pretty safe bore.