odarabla

iTrader: (1)

I've decided to start on my new motor. It's going to be a 414ci LQ9 6.0 LS1. 4.000 crank, 6.125 stroke, 4.060 bore. The question I have is, I already have the 215cnc Trick Flow heads that are on my stock short block. I talked to Brian Tooley already and he said try to sell the heads and get the 235CNC heads for my build. What would you guys do? How much more power would I make going with the bigger intake runner and valves over what I already have? I plan on using the vic. jr. intake with the elbow and NW 90mm TB.. Also, if I stay with these heads they have a 62cc chamber and I am going to be using flat top pistons which would bring my compression to about 12.0:1. I could have a cam cut to fit these heads on this build but how much would I be short changing myself? The other thing is I really don't want to take a big hit on the heads I have now. They are pretty much still brand new. I've only had these heads on my car for about 8 months and the car isn't my dd. What would you guys do.. And how much would these heads effect my build? Thanks guys for all your help..

CalSpeedPerformance

iTrader: (64)

I personally think the 215cc head will still make very good power. You see alot of fully ported 5.3l/ls6 heads on 403-414 cube motors making good power. I think the 235cc heads will pickup approx 15-25 rwhp over the smaller heads

smok'nZ

iTrader: (160)

thats a big miss match if you dont want to take a loss keep them on your stock shortblock and buy something else but whats the point in spending thousands on a 414 and use 346 heads?

bluecamaroz28

If you keep the bore at 4.0" or 4.020" and open up the chamber on those TFS heads, you might be okay. If your on budget, you can get patriot LQ9 heads and sell the trickflows or keep them on your stock engine.

mikey

iTrader: (6)

The 215 heads with my Dominator 2X cam would be a torque monster! You'd need valve reliefs in the pistons though

Qwiknotch

The TFS 235's will work on a 4inch bore. I put my ls2 block at 4.010 and we had enough room by far to put a 2.100 intake valve in it. Granted, there is a small shelf around the exhaust area of the chamber since the 235's chamber is 4.125, but it will still fit. I'll let you know the power it makes when I get it done in the next month..waiting on pistons and valve springs and the cam right now.

odarabla

iTrader: (1)

Sounds good thanks!! I just have to sell my 215CNC trick flows first..

03 BUSA

iTrader: (25)

I would agree that the 215's are too small.