I'm considering doing a 408 and I was just wondering if anybody else had this set up and how they liked it. It'll be in a 02 T/A 1 7/8s headers, 4" exhaust, FAST 102, 4" intake tract, stick car 430 geared. Just curious if anybody else was running this set up or similar set up. What kind of power they're making, driveablity, track times, peak rpm etc. I'm trying to decide between doing this or a 370 with a prc 215 and MS4 or possibly a polluterv2. I all ready have a set of 215s. What do you guys think?

 

I battled that same question when shopping and opted for the 370 simply because of the price. The 215's with a MS4 cam and a Fast 102 is still going to be a screamer on that 370

 

530-550rwhp and 470-490rwtq in the 408.

The 370 would be probably more like 500-510/450-460.

So, not a huge difference. Since you already have the 215s, it might be more cost effective to just go with the 370. However, if the 215s are unused, you could sell them and get the 247s and the 408 without losing your shirt.

The 408 wouldn't be that much more than the 370. Maybe $800 more. It will make more HP/Tq but the difference is much less than going from a stock motor to a h/c setup. You are adding bore and cubic inches with the 370, so it will perform more like what you see from LS2 h/c combos vs LS1s, and they are usually up a good 20-30ft/lbs over the LS1. The 408 would just add another 30 or so on top of that. The added cam and heads will add about that much HP as well.

 

The 215s are used. They were on the 346 and it made 490. I do want to avoid the MS4 its brutal on the valve tips. Since I'm only looking at a 30hp/tq difference I think I'll just go 370 and possibly re gear and spray it. Will the power I'll pick up from the 370 justify the extra weight? Basically what I'm asking is should the car pick up ET from the swap to a 370 over the LS1.

 

It probably won't pick up much ET. The added torque of the 408 would tho. Remember, the 408 will be up about 60ft-lbs over the h/c ls1.

 

Put the 215's on the 408 with a good cam to match.

Everyone thinks they need huge port volume to make big power or even respectable power.

You don't!

 

You can send the 215's back and they can run a larger port program on them. The 215's will make for a very responsive 408 and still make good power.

 

What cam would you recommend for a 408 with the 215s. The only thing I'm worried about doing the 408 and 215 is having to stick a dish piston in to make up for the 60cc head. What would be my best bet on over coming that?

 

An -8cc dish piston would work fine for 11.5-11.6:1 compression assuming a zero deck and .051" gasket.

The smaller cross section of the 215 will need a slightly later intake valve closing event and the smaller exhaust port cross section will need a slightly earlier exhaust valve opening event.

This is in comparison to a larger head. Still doesn't mean it won't make good power.

Something that will drive well and make good power IMO would be a 243/250 .624/.595 114+3.

If you wanted to shoot for some bigger hp/tq numbers you could run a .040" gasket which with a 60cc chamber and 8cc dish piston would give you 11.9-12.0:1 compression.

I'd pair that with a 247/254 .624/.595 113+3 camshaft.

Couple options for you at least.

 

With the 12.0:1 compression and the 247/254 I can run pump gas correct? And how would that cam do if I ever did go with a different head down the road or is their really any need in it?

 

What is the altitude where you live or the density altitude on average? I see that you're in VA.

Altitude and DA can have a huge impact on the ability to run a given octane. I have done it with many customers in the past before and they make big power numbers while running well on pump gas 93.

 

I honestly have no clue. Its Hurley, VA 24620. I know when we run at Bristol (about 2 hours away) the DA is usually 2500 or above.

 

You should be fine IMO then.

 

I started thinking the same way, VandykeT/A.

A 248/254 113+3 camshaft, TEA Stage 2 heads opened up for the 4" bore with 66cc chambers and anti-detonation work done to the chamber, 2.055" turned down LS3 valves on the intake, and 2cc Diamond flat tops in an LS2. 12.1:1 with a quench of .035". Something similar should make 500rwtq and maybe 530-540rwhp with a ported FAST 102 and 1-7/8" headers.

 

Like Martin said, run the 215s on the 408. I did it with great results and wouldnt hesitate to do it again. I made almost 530-500 with them and the cam was just an off the shelf I picked and it was a handful.

 

408 without a doubt! No replacement for displacement!

 

this is what i made with the prc 247s with a similar cam to the tsp giant and 11/1 compression on a 418 ci motor

 

More compression and more header would bump your power up.

 

Forget the HP look at the torque!

 

yeh the bigger cube motor pulls good everywhere... my buddy has a c6 ls3 gran sport with a 233/248 cam, 1 7/8 headers and intake and i pull him from 40-140 while shifting like i'm going to the country club on a sunday