budd.26

I have a LQ4 6.0 that I recently installed a Texas Speed 228R cam and 799 heads with ls1 exhaust manifolds. It also has Fast injectors to support the mods. It is in a 1963 Toyota FJ40 Land Cruiser 4x4 with 4L80E transmission. I recently had it tuned and on 31" tires it dynoed 310WHP. It made peak power at 5300 and whats worse the horsepower never exceeded the torque. Texas speed rates their cam to make peak power at 6300 in an otherwise stock engine. Also the horsepower should always exceed the torque in a cam of this type. I am at a loss as to what would cause it to do this. The engine otherwise appears to run normal and good. The tuner could not figure it out and said it must be because I am running the stock truck intake manifold. When I talked to Texas speed they said their testing was done with a factory truck intake, so that rules that out. I have searched the forums but have not found any answers. Any ideas? I would really appreciate the Help!

Darth_V8r

iTrader: (4)

I bet your cam is off by a tooth. Advanced.

vwdave

iTrader: (3)

Mine did the same thing. I was given the wrong specs to degree the cam to and it was 5-6* advanced. I retarded the timing and picked up 17whp without any tuning changes.

jimmyblue

iTrader: (11)

If you have stock exhaust manifolds, what does the
rest of the exhaust lineup look like? Back pressure is
a flow killer and flow equals horsepower.

budd.26

It has 2 1/2" duals from the manifolds for about 4 feet then into dual 3" flowmasters and pipe to the back. I had to run manifolds because I could not find any headers that would fit. Will probably be making headers in the future

budd.26

It sounds as though I need to take it back apart and check cam timing. Does anyone know if the factory timing set has a built in advance or retard? I set the cam for 0 when installed as the cam specs said to do.

Darth_V8r

iTrader: (4)

The factory timing set is straight up. That said, I've seen factory timing sets that were not correct. I'd suggest for $38 if you're going in there, get a cloyes 3220 LS2 timing set. Matches stock LS1,2,6, and the chain is stronger than LS1 chain.

It's quite easy to think it is installed straight up and actually be off a tooth. I use a ruler to go from cam centerline to crank centerline and make sure the dots are centered in the ruler. For example, if you're advanced by a tooth, the dots will actually line up, they'll just line up slightly left (or passenger side since you're looking at it backwards) of center. If you can't get a good angle to look at it, it'll actually look lined up!

Even having done the ruler trick, I still like to degree the cam to verify the intake centerline is as specified on the cam card

budd.26

thanks for the good info. I will be tearing back into it the first chance I get. I will let you guys know what I find