im running dart 225's, 62cc chambers on my 403. i dont have dyno numbers yet but its faster than when i had the P1@6psi... 518/459. dont add FI without building the bottom end. i have #5 & #7 pistons sitting in my garage to prove stock internals cant handle it. btw, 21CMC/LPE did the work so no one can say it was who ever installed and tuned the car. They are one of the TOP FI specialists in the US.

i think the easiest way to get there is to pull the motor add a 4" crank, but the block will have to be machined and clearanced for h-beam rods, down time for the build maybe a month from start to finish. rent a car in the mean time. that or add a 50-75 shot dry or wet which ever you prefer. you could also look into street tuning your car, data log it and have someone go back over all the parameters to get the most out of it. 4th gear pull on a dyno doesnt do what you need in order to tune the PCM efficiently.


the darts seem to be in between as far as price vs all of the other heads mentioned, that is why i went with them, but got lucky and paid 1k for mine, hand finished, 5 angle valve job and ceramic coated. performance wise i dont think there are many darts running around on this site anyway to get a good positive feed back. these heads made 442/414 on a 346 with a 228/232 cam and ls6 intake. yes i bought them used from a friend who had them on his car for 1200 miles. he is running another set of experimental dart 225's that came from dart. as far as flow my darts flow similar to the patriot stage 3's. but port design, velocity, filling the cylinder and all of the other things go with the equasion is what makes the numbers.

btw your firewall in your C6 has to be modified to fit a fast 90. i think its funny people are making a recommendation without knowing the facts on a c6 before hand.

 

Yea, the firewall will have to be cut. Correct me if im wrong but i think there are a few companies charging around $600-$800 to install the FAST manifold on the C6's.....

 

spray that ****!

 

cut the fire wall WTF that's not going to happen, looks like maybe i try the spray, any suggestions?

 

Honestly, when I saw a person who has enough lettuce to buy a C6 and IFroge wheels, then replace all the fenders with ZO6 fenders, and with all the performance mods you have... then buy Patriot heads? I was like, WTF?!

I bet you'd net another 25-35+ rwhp and good power under the curve with a set of AFR 225's, but not quite 50 rwhp I doubt. The new TFS heads are making quite a spash, but the AFR's have a longstanding reputation and often-proven results. It'd be a tough choice, but with the kind of money you have going into your ride, Patriot wouldn't even be in the running.

Now, for me, Patriots and TSP's heads are at the top! LOL! I'll never be able to afford AFRs!

Hell, just pull the bastaard and stroke it to 402" and run a dead secksi sheet metal intake. You got the money.

But, I'm no expert, I'm just throwing that out there. My only experience is looking at dyno graphs every day for the last few years. Take my advice with a grain of salt.

 

we sound alike, i turned towards the bottle also....

 

Not everyone can do it big all the time. Maybe he was on a budget or had a budget in place, then purchased all his top line items first and when it came down to the heads, maybe the AFRs would have thrown him off budget which is probably why he went with TSP.....

 

 

It is a budget thing, every time I get something for the car the wife thinks she should get something as well so it’s kind of like doubling the budget. So if I look at spraying what could that cost a new pair of cheap ear rings or watch?

 

trick flow 225 heads
underdrive pulleys
ported TB and
ported fast intake should put you right in the range you are looking for

 

......OR, you can put on a set of heads that actually fix the major problem with the LS1 cathedral port cylinder head, that being the size of said port.....it's WAY too big in cross section for the amount of air it moves and the geometry of the port floor is all wrong (why do you think GM made the C5R head, and now the LS7 and L92 heads?). We are finishing up our CNC port design for the GM 5.3 head which changes the port configuration to something that works much better than ANY other cathedral port head out there. Testing has already shown it to make more power and especially torque with less camshaft (meaning better driveability and throttle response) than any other head we have used, by far. This first head program should be used on engines from 5.7l up to moderately wild 6.3l's (346" to 383"). We will be looking at practicallity of a version for bigger engines (they may be better served by modified L92 style heads). These heads DO require a manifold specially matched to the heads.

Brian
HiTech Motorsport