ZFSix

iTrader: (14)

The car is not making much power at all, and I think we have narrowed it down to the cam being wrong for the motor.

Specs:

12:1 347ci shortblock, Wiseco pistsons, Manley rods, polished and balanced stock crank
Livernois Stage II LS6 heads milled to 62cc
Fast 92/PTM 92mm TB
Kooks 1-3/4" headers
42# Injectors
Racetronix fuel pump kit with the hotwire

Right now it has a 236/240 .601/.608 111+2lsa cam. It seems to run decent, but only put down 399.7rwhp and like 386rwtq. Weak!!

I was thinking about the HPE Big E cam, 244/248 .612/.615 112lsa.

Thoughts?

bigfatls6

iTrader: (34)

Is this an auto or 6 speed car? Did you have the cam degreed when it was installed? Who tuned it? i wouldn't jump to just swaping cams. You might swap the cam and only gain 3-5 hp. There are some cam only auto cars on here with smaller cams than the one you have makeing 420 rwhp. There probly something not right in the tune or valve train / cam timing. Maybe your clutch was slipping?

s346k

iTrader: (4)

t-rex.

PREDATOR-Z

You have domed pistons?
How are you getting 12:1 with 62cc heads, with .01 piston out of hole and .040 gasket, 2cc reliefs, I'm only getting 11.2

Is this a Mustang dyno?

ZFSix

iTrader: (14)

+6cc dome.

2 different Dynojets, Chuck (formerly of HPE) did the tuning. He has tuned my car 3 times before with no issues. It does run a little rich, but this setup should be making upper 400s, so I doubt tuning is going to get me 80+hp. The first pull untuned was 325hp...

It is a 6 speed also. The clutch grabs a little late but doesn't slip. Also I don't see that making 80hp as well. At first I thought something was off with the dyno so I took it to another shop and the 2 dynos were within 10hp of each other.

The cam wasn't degreed with a wheel, just lined up to 0 degrees with the dot on the other gear. It is a double roller chain.

Sales2@Texas-speed

iTrader: (5)

The quickest 346ci heads/cam car in the country runs an MS4

SOMbitch

iTrader: (8)

I don't think your cam choice is the problem. That cam should make good power. Something else must be going on.

3.8to6.0

iTrader: (10)

I agree. The cam you have looks very similar to EDC's original streetsweeper grind.

novaflash2002

iTrader: (51)

236/242 .600 .610 112+2 preaty much the g5x3

PREDATOR-Z

Did you datalog any KR.
Accorging to my calculations I am seing ~9.0 DCR which is detonnation territory with domed pistons.
I would say tune is part of issue.
What plugs are you running?

ZFSix

iTrader: (14)

Those funky E3 plugs are in it right now. I still have my old NGK TR55s, but I don't see that making a huge difference.

What if I put a mix of race fuel in it?

PREDATOR-Z

For sure you'll need a colder plug than TR55, instead of running around in circles you should live scan and record at various rpms to see what is happening.
You said it is running rich, that had to be for a reason (clue)

Sales2@Texas-speed

iTrader: (5)

You said it runs a little rich. Do you know this because it read rich on the wideband or because it smells like fuel??

With that compression, you'll want to run some race gas mix in the tank to avoid pinging/detonation. Also a cooler plug like Predator said would be to your advantage!

ZFSix

iTrader: (14)

What would a colder plug be?

Unfortunately the wideband was not working when he tuned it... so it was a guess. I am talking to another tuner around here to retune it because I am not happy with the way Chuck did it.

So I am basing it on smelling like fuel, it is horrible standing behind the car, even driving it with the windows down or up you can barely breathe.

JL ws-6

iTrader: (50)

Ya need to log the dyno runs and see if there's any knock pulling the timing out. You definately have something going on, I made 403 cam only in 2003 before any of the new technology came out.

Granted, the motor is probably built with heavier then stock components that aren't going to help make power, but you should be seeing in the 450+ range with a stick in the car.

The cam you're running isn't so small that it shouldn't me making a good bit more then it is.

I agree that you probably need some 100 octane gas, probably don't need leaded fuel, but something better then pump is probably needed.

I'd put a set of TR7 plugs in the car, that would be a good starting point as well.

ZFSix

iTrader: (14)

I know the numbers are horrible, I made 436rwhp cam only before I built this motor, with a Fast 90 and 244/242 cam on the stock heads and stock bottom end.

I'll order a set of TR7s and try some race fuel along with a retune and see where it gets me.

JL ws-6

iTrader: (50)

Can't hurt, I don't know what you have available for race fuel, if you have an unleaded 105 or something like that I'd start there, if not a 5 gallons of C10 and4 to 5 gallons of 93 should be fine as well. I assume there's no cats in the car to get screwed up, and if you tune it open loop the o2's aren't gonna be a problem with leaded fuel.

But if you are running the o2's the leaded fuel is gonna be a problem, cats, even with unleaded fuel won't be happy either.

Super Speed

iTrader: (8)

Be sure to post back here, I'm interested in what happens!

LS1-450

iTrader: (33)

....Ask for your money back because you surely didn't get a proper tune without the wide band.

LS1 SPEED

iTrader: (22)

yeh... how can a car be tuned with no wide band and know things are good?

cam should not be an issue

TR6 should be a good starting point for plugs

good luck getting it sorted out