So here is my dilemma. When I bought my GT the guy could not find the cam card and he is still looking for it. He cannot remember what brand of cam it is or what duration the cam has. All he knew was that it has 512/525 lift. Anyway to tell without pulling it out and checking? He also said that it was a custom grind for the supercharger.
512/525 lift Duration ???
- Thread starter toxzzic1
- Start date
If you remove a valve cover and a set of intake/exhaust rockers, all you need is a dial indicator with a magnetic base. You can measure lobe lift at the end of the pushrod. Removing your spark plugs helps with turning the engine over by hand. Multiply your lobe lift x your rocker ratio and then you will have your gross lift numbers.
At this point there are only 2 ways you are going to find the duration. One way is to pull the camshaft out of the engine. The other way is with a degree wheel and aforementioned dial indicator.
It could be anything. Depends on what the goal was when the cam was designed. You'd have to take a lot of accessories off to be able to mount the degree wheel. That also includes pulling the balancer off. It may not be worth all that work just to find out what the duration is.
It could be aaaaaaaaaaaaaaanything, especially considering it was a custom. If you're really worried about it, and/or have intentions of replacing it, tear it down and measure it. If you really have no intention of changing it, just drive it and enjoy it. 
I just wanted to find out if it was the best cam for the application. Right now up top it has gt-40 ported and polished heads and a typhoon upper and lower intake. I am looking at replacing the heads with AFR 185's and a new trick Flow intake. I am still trying to decide whether to use the track heat or the box-r. So I may change the cam for the upcoming changes. Do these sound like good changes to make or is there anything that you would do different?
Is it a stock bottom end? If so, you may run into piston-to-valve trouble with those AFRs. You could just run Trick Flow heads if you're going to run a TF intake.
Yes it is still supercharged running 6# of boost with a Powerdyne bd11-a unit. Right now the car runs 11.7 in the 1/4. I am wanting to get into the mid to high 10's. So what intake would you recommend. I am using the Typhoon upper and lower. I am looking at going with the TFS Track Heat or the Box-R intake I am also looking at changing from the ported and polished GT-40 heads to a set of AFR 185's or TFS Twisted Wedge heads? Will not knowing exactly what my cam is cause a problem making a choice? Would you recommend one setup over another? I am also looking at changing to a Vortech s-trim and selling the Powerdyne.
Those numbers are already pretty good.
Definetely get rid of the powerdyne while it's still working, when it let's go (and it will), repair is unlikely. Sounds like you push the car hard so the sooner you rid of that SC, the better.
For clearance issues, that's a car by car basis.
Unknown cam, unknown piston specs make it tough to call.
165's or standard tw's would probably be your best bet.
For an intake i like the edelbrock rpmII.
Definetely get rid of the powerdyne while it's still working, when it let's go (and it will), repair is unlikely. Sounds like you push the car hard so the sooner you rid of that SC, the better.
For clearance issues, that's a car by car basis.
Unknown cam, unknown piston specs make it tough to call.
165's or standard tw's would probably be your best bet.
For an intake i like the edelbrock rpmII.
2vNotch
Active Member
lol sounds like some1 got bit by the mod bug! dont worry happens to all of us and then this "wondering" begins...we already have a stout combo, but is it maxed to its potential?? Sounds like u got a good combo there and if u really wana push it buy a water/meth kit and call it a day...Its much cheaper than the few horses ur gnna gain spending thousands do H/C/I swaps...and remember, a good, light suspension package changes track times too Good Luck!
Good Luck!I am actually looking at a water/meth kit. hoping to have it in a couple of weeks. I guess I will start looking at a S-trim and see where that gets me along with the water/meth kit.The car already has about every suspension mod you can get so no room to grow there. I guess I will start changing a few things under the hood. Right now I am running a clutch fan and stock radiator. So I will be changing to an aluminum radiator and dual electric fans.lol sounds like some1 got bit by the mod bug! dont worry happens to all of us and then this "wondering" begins...we already have a stout combo, but is it maxed to its potential?? Sounds like u got a good combo there and if u really wana push it buy a water/meth kit and call it a day...Its much cheaper than the few horses ur gnna gain spending thousands do H/C/I swaps...and remember, a good, light suspension package changes track times too
2vNotch
Active Member
If he hes a motor build sheet it may give you the PT# of the pistons, most of Probes SRS series pistons use to be dual relief..so you can run decent lift/duration with a 2.05" intake valve with either a inline or twisted wedge head. Id have a very different cam with the new parts you are considering BUT you do not need to get crazy with a blower cam and what you have right now may work great. IMO, small duration as long as you have a decent split will work great.
With a AFR185, TW190 Id like a RPM II or a Holley Systemax intake..
I like the meth idea on either combo.
I'd add the meth and enjoy the combo till your ready to buy a new race block set-up that can take the extra power.
With a AFR185, TW190 Id like a RPM II or a Holley Systemax intake..
I like the meth idea on either combo.
I'd add the meth and enjoy the combo till your ready to buy a new race block set-up that can take the extra power.
My main goal is to have a 500 rwhp car. Looking at what I have can you tell me what I need to change the get where I want to be.
Powerdyne bd11-a making 6# of boost
eagle rods
forged probe pistons,
forged crank.
GT 40 heads ported and polished
Typhoon upper and lower Intake,
GT spacer 1" BBK spacer
BBK 75MM TB
36# INJ
BBK headers
H pipe
flow masters,
373 gears,
all susp upgrades, with rear lakewood cal tracs,
racing clutch, with adjuster,
msd 2 box with rev control.
255 in-tank race pump.
Currently 348rwhp
Powerdyne bd11-a making 6# of boost
eagle rods
forged probe pistons,
forged crank.
GT 40 heads ported and polished
Typhoon upper and lower Intake,
GT spacer 1" BBK spacer
BBK 75MM TB
36# INJ
BBK headers
H pipe
flow masters,
373 gears,
all susp upgrades, with rear lakewood cal tracs,
racing clutch, with adjuster,
msd 2 box with rev control.
255 in-tank race pump.
Currently 348rwhp
Right off the bat, you need to ditch the Powerdyne, if for some reason it could produce that much power, you would blow it up shortly thereafter.
With an S trim, 500rwhp is fairly easy.
The question is how much boost you want to get you there.
IMO, the less boost it takes to get you to your goal, the better/more reliable the car is.
So if you can use the cnc wedges or afr 185's, by all means do so, rpmII intake, custom cam.
42 injectors.
That's pretty much it.
Just remember, the stock block no matter what pistons rod etc will only put up with 500rwhp, and honestly even that's too much. Sounds like you are going to drive this car hard, which i can appreciate, but it may not last long at that number.
450rwhp sounds like a better idea, and you may be able to get close with just a supercharger swap with a pulley. Just remember what i said above, less boost=more reliable, and with gt40p heads (of any sort) the boost level is going to be much higher than with tfs or afrs's.
With an S trim, 500rwhp is fairly easy.
The question is how much boost you want to get you there.
IMO, the less boost it takes to get you to your goal, the better/more reliable the car is.
So if you can use the cnc wedges or afr 185's, by all means do so, rpmII intake, custom cam.
42 injectors.
That's pretty much it.
Just remember, the stock block no matter what pistons rod etc will only put up with 500rwhp, and honestly even that's too much. Sounds like you are going to drive this car hard, which i can appreciate, but it may not last long at that number.
450rwhp sounds like a better idea, and you may be able to get close with just a supercharger swap with a pulley. Just remember what i said above, less boost=more reliable, and with gt40p heads (of any sort) the boost level is going to be much higher than with tfs or afrs's.
