I'm almost done with the chassy work, and have begun to start planning and mapping out the 355 boost ready Lt-1...

I"ll be lifting the engine out this summer... but I want to get my heads on in the mean time.

For a head setup that's not short of breath...

I've decdided to go AFR... and then have them hand ported afterwards...to make sure they flow where they should be. So far I'm not sure what heads I would want to go with. The car will be Forged 355 with an 8 to 1 ratio... but I won't have the turbo on there for a while... so in the mean time I plan to return to the world of N20..until my LT-1 fund kicks back up. I plan to spin the car to the 6.5K + rpm range with Turbo in mind... so I need the heads that are imost ideal for that...but on a side note I need to keep emissions in mind... and still am unsure of how emissions friendly any of these heads may be.

215cc raised Runners
210cc LT4 SBC Racing
220cc LT4 SBC Racing
227cc LT4 SBC Racing


Would do you guys out there running similar setups reccomend best for a TUrbo/Nitrous motor .. I'm aware all of these heads are N20 ready so AFR claims... but I'm more worried about emissions... than anything else...since all of these heads are "Race"versions...

Right now I know that I don't need a set of heads that are extremely "breathy"... since the car won't exactly be dependent upon all motor power alone... but I do want the heads that will still breathe the best if I didn't have a turbo setup planned.

What suggestions and reccomendations do you guys have?

O yeah... and they will be used in conjunction with a custom grind turbo cam...

 

The 215 RR's would make the most power, but I doubt you're willing to spend the bucks to get those to work.

Given the options, at 355 cid, I'd get the 210's. They're slightly bigger than you really need, but flow way better than the 190/195's even though AFR's numbers don't show it. I wouldn't do the 220's unless you were 383 cid, and the 227's unless you're 400+ cid. I've seen a 230 cc head hurt the power of a NA 355 because it was simply too big of a port.

 

210's hungh.... hmmmm

okay we're getting somewhere....

So how much trouble is it to run the raised runner 215's?

 

I've been perfectly happy with my ported 195's. But the 210's might be a better choice though you will lose some port velocity when not in boost and the car will seem a little "softer" and less responsive at light throttle, especially if you have a big cam. But I would absolutely not bother the the raised runner heads. Before I would do that I would adapt a set of gen I heads.

Rich

 

Raised runner heads require a custom intake manifold and shaft-style rockers. Not to mention, the heads alone are $500 more than conventional.

 

I see.... 210's are ideal... I estimate I'll have close to 3 g's dropped into the heads when I'm done....


but even at low boost those are ideal hungh....

Do you guys think it's better to by the race ready version... or competition package... if I'm goign to have them cleaned up anyway?

 

I bought AFR 210 bare castings (completely unported). I sent them to Lloyd Elliott along with some valvetrain and had him port the heads for me (total cost for bare heads, porting and valvetrain ~$2000). Check out my post and look at the flow #'s I just got from him. They are much better on the intake side and a little less on the exhasut side compared to the full compettiton porting by AFR (according to their flow #'s).

http://web.camaross.com/forums/showt...86#post2676286