VandykeT/A

I've got a 408 T56 car that made 570/522 on a loaded dynojet. Above 6800 the car has a noticeable power loss at the end of the track. I can feel the front start sitting down then I'll eventually hit the limiter. It doesn't have a misfire or erratic feeling. It just seems like It just starts losing power those last few hundred rpm. Is it possible the intake isn't flowing enough air up in the 7-72k range. It's a vengeance ported 102, 102 TB, fast toys 104mm lid speed density and chrs1313. Heads are PRC247 251/259 cam. 11.5 compression with 1 7/8 headers and 4" exhaust.

HCI2000SS

iTrader: (2)

If you are only wanting to rev to to 7k then the 102 should be plenty from what I understand

scotty2000ss

iTrader: (2)

Does the intake have the runners shaved down or are the ports cleaned up? Or both lol

MonmouthCtyLS7

iTrader: (6)

I doubt the problem is the Fast, especially seeing its ported by Vengeance.

hellbents10

iTrader: (10)

Need to see what kind of manifold vacuum you have at 6800+. If its little to none, then the intake is good at that point. I would suspect valvetrain first though.

Rise of the Phoenix

iTrader: (27)

I agree that the issue likely lies in the drivetrain. I don't see the FAST intake being the issue, especially only taking it to 7,000 to 7,200 RPM's.

redtan

iTrader: (5)

I would say the same thing, sounds more like valvetrain related than not enough airflow from a ported FAST 102.

kinglt-1

iTrader: (26)

sounds like valvefloat....even if the intake was a restriction, you would not feel the car fall over on the big end.

farmington

iTrader: (14)

check your sparkplugs. try closing gap down .003-.004

Rise of the Phoenix

iTrader: (27)

On a side note, what exactly are you running in the quarter mile, and what's the trap speed? If I remember right, this car put down some really high dyno numbers.

dr_whigham

iTrader: (49)

Yeah, I'd like to know the kPa from the MAP from 6k to shift myself...

KingJacobo

Just curious, if a fast 102mm was bottle necking you what would be a better flowing intake?

I always thought the 102 was the holy grail of street LS intakes.

VandykeT/A

Car made 570.63 and 522tq on a loaded Dynojet. I think the loading jacked it some. It made 535 through the air box set up. Loaded the dunk and it made 555. Pulled the lid and ran open bellow and jumped to 570.