Rwhp
Le Mans Master
Joined: Mar 2001
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From: Watkinsville, GA and Glen Cove, NY
I would guess that you would be at 500 wheel horsepower with that combo but that cam looks very small to me. Those AFR's like lift and the Super Victor is a high rpm manifold. 540's can really tame a cam from combos I have seen. Should be a fun combo though.
Safety Car
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From: Pettis Performance 565 with two stages of Nitrous Supply nitrous 1.082, 4.61 at 155, 7.17 at 192
Ya, about 500....but that cam is too small. In the famous words of 427Hotrod "it as a weenie cam.""
There is probably 50 rwhp in a bigger cam.
What is the rest of the combo, compresssion ratio??
There is probably 50 rwhp in a bigger cam.
What is the rest of the combo, compresssion ratio??
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From: Corsicana, Tx
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Do a search on TNBusa..he built a 540 with AFR 315's and a Super Victor recently. He used a relatively small cam also for nice manners and good life expectancy and he made 719 or so flywheel HP. Probably good for 730 or so since his carb was real rich during the testing.
Is the motor already running? I'm assuming you can lock up the trans? That 4l80 is going to eat some power I imagine.
JIM
JIM
Is the motor already running? I'm assuming you can lock up the trans? That 4l80 is going to eat some power I imagine.
JIM
JIM
Race Director
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From: Lenoir City Tennessee
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Do a search on TNBusa..he built a 540 with AFR 315's and a Super Victor recently. He used a relatively small cam also for nice manners and good life expectancy and he made 719 or so flywheel HP. Probably good for 730 or so since his carb was real rich during the testing.
Is the motor already running? I'm assuming you can lock up the trans? That 4l80 is going to eat some power I imagine.
JIM
JIM
Is the motor already running? I'm assuming you can lock up the trans? That 4l80 is going to eat some power I imagine.
JIM
JIM
Weenie cam at idle.
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Instructor
Joined: Mar 2007
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From: Henryville Indiana
Unless the engine is already together CHANGE CAMS!!!!!
Thats an awfully small cam.You could run STOCK heads with it it's so small!
I had a 468 BBC in my 79 Camaro drag car that had a Lunati 722/722-258/262 Roller in it with oval port heads and a Victor 454 and an 850.It idled at 1000,11" vacuum and pulled 707hp,649# torque at a 7400 redline.
Car ran 6.30 1/8th mile ALL MOTOR.
You can go close to 700 lift and in the mid 250 duration with a wide lobe center and still have a civilized combo.
The heads are overkill for the cam.....Use 1.8 rockers to get more lift.
Thats an awfully small cam.You could run STOCK heads with it it's so small!
I had a 468 BBC in my 79 Camaro drag car that had a Lunati 722/722-258/262 Roller in it with oval port heads and a Victor 454 and an 850.It idled at 1000,11" vacuum and pulled 707hp,649# torque at a 7400 redline.
Car ran 6.30 1/8th mile ALL MOTOR.
You can go close to 700 lift and in the mid 250 duration with a wide lobe center and still have a civilized combo.
The heads are overkill for the cam.....Use 1.8 rockers to get more lift.
Team Owner
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
I'd say that it's about 430 - 450 RWHP as a 4L80 is used.. The 4L80 is stong but has a huge parasitic loss.. Expect 35% loss through drivetrain and accessories with the 4L80
If you have a restrictive exhaust, probably even more..
If you have a restrictive exhaust, probably even more..
Last edited by GrandSportC3; Jun 11, 2007 at 07:35 AM.
Le Mans Master
Joined: May 2006
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From: League City Tx
Assuming your 540 EFI makes 700 crank hp, less 30%(at least, probably more like 35%) for parasitic loss through the 4l80e/stall converter and IRS, you should end up with around 480-500rwhp. 455rwhp based on a 35% loss. It really depends on how much power it made at the crank.
Guys, he probably went with the smaller cam so its easier to tune the EFI. Plus he probably wants it really driveable and able to run accessories easily.
Guys, he probably went with the smaller cam so its easier to tune the EFI. Plus he probably wants it really driveable and able to run accessories easily.
Race Director
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From: Corsicana, Tx
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Well it IS a weenie cam!!
But I DO see the need for it depending on application.
The beauty of building a BIG motor is that you CAN build it with things like milder cams and still get *X* perfromance/HP. That way you get the power as well as great manners.
The problem most of us have is that with a motor that big....they just flat respond to anything you can do to get air in them and you can get some big increases pretty easily. It's like crack...easy to get addicted to! But of course comes all those nasty issues...like poor manners etc.
The 315's are excellent heads and will support 700-750 HP without any trouble even using smaller cams. That's the beauty of them. For 800 Hp range the 335's or 357's make it easier especially with larger cams.
For what you've described, you might not be off too far on cam.....it WILL be a TQ monster! If you don't have rockers already, throw some 1.8's on intake side for sure.
Isn't it funny how 700 HP is where we START to get excited these days for our pump gas street motors? There was a time when Pro Stock's were aiming for 600 in race trim!!
JIM
But I DO see the need for it depending on application.
The beauty of building a BIG motor is that you CAN build it with things like milder cams and still get *X* perfromance/HP. That way you get the power as well as great manners.
The problem most of us have is that with a motor that big....they just flat respond to anything you can do to get air in them and you can get some big increases pretty easily. It's like crack...easy to get addicted to! But of course comes all those nasty issues...like poor manners etc.
The 315's are excellent heads and will support 700-750 HP without any trouble even using smaller cams. That's the beauty of them. For 800 Hp range the 335's or 357's make it easier especially with larger cams.
For what you've described, you might not be off too far on cam.....it WILL be a TQ monster! If you don't have rockers already, throw some 1.8's on intake side for sure.
Isn't it funny how 700 HP is where we START to get excited these days for our pump gas street motors? There was a time when Pro Stock's were aiming for 600 in race trim!!
JIM
Team Owner
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Assuming your 540 EFI makes 700 crank hp, less 30%(at least, probably more like 35%) for parasitic loss through the 4l80e/stall converter and IRS, you should end up with around 480-500rwhp. 455rwhp based on a 35% loss. It really depends on how much power it made at the crank.
Guys, he probably went with the smaller cam so its easier to tune the EFI. Plus he probably wants it really driveable and able to run accessories easily.
Guys, he probably went with the smaller cam so its easier to tune the EFI. Plus he probably wants it really driveable and able to run accessories easily.
Last edited by GrandSportC3; Jun 11, 2007 at 12:11 PM.
Le Mans Master
Joined: May 2006
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From: League City Tx
I highly doubt that the engine makes 700 HP with that little cam.. My small block cams have a lot more lift and duration that this little cam.. The low compression doesn't help either.. I'd say that the engine makes about 630 HP - 650 HP at the crank (probably even less than 600 HP) and 430 - 450 RWHP (or less) at the rear wheels... and that's a very optimistic prediction.. That would also require open exhaust or race mufflers.. With street mufflers, I'd bet that you'll make 400 RWHP AT MOST!!!
Man would I be pissed if my high $$ 540 only put 400 to the wheels....
Hell a buddy of mine has a stock ZZ502, only change to it was to a 850 double pumper and it made 360 rwhp through a Th350, 2500 converter and 3.73s in a 10bolt...I couldn't imagine a 540 with well over 100+ hp more only making 40 more to the wheels.
I guess we'll all see when he dynos it.
Big motors just make more power, straight up. Another friend of mine has a cast 496", edelbrock oval ports that are lightly worked, an Ultradyne hyd flat tappet and a performer RPM and it made 611hp on an engine dyno on pump gas. Its around 10.25-1 he says. The cam was only like 236/238 and .580 or so lift. He put this motor in a 66 Chevelle with a Th400, decent converter and 3.73s and it went 10.90s@121. Guy drives that car EVERYWHERE.
Safety Car
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From: Pettis Performance 565 with two stages of Nitrous Supply nitrous 1.082, 4.61 at 155, 7.17 at 192
I highly doubt that the engine makes 700 HP with that little cam.. My small block cams have a lot more lift and duration that this little cam.. The low compression doesn't help either.. I'd say that the engine makes about 630 HP - 650 HP at the crank (probably even less than 600 HP) and 430 - 450 RWHP (or less) at the rear wheels... and that's a very optimistic prediction.. That would also require open exhaust or race mufflers.. With street mufflers, I'd bet that you'll make 400 RWHP AT MOST!!!
Le Mans Master
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From: League City Tx
I AGREE!
If you ever talk to anyone from AFR, especially Tony, you will know they are a huge advocate of small cc, high flow ports and "small" cams. The great flowing heads make up for the lack of long duration cams yet the small cam and small ports make for strong low to midrange. Even on their website that has 383" motors making 500hp, its only with like a 232* hyd roller cam, 10.5-1 compression and an RPM air gap intake. They really prefer velocity and cylinder filling as opposed to long duration/huge cams.
Cubic inches make up for sheer rowdiness 90% of the time.
He is gonna have a torque monster here. That thing is probably gonna run 10.80s with a 3.08 gear....
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All that cool velocity stuff is great...but there is a point where you need *X* cross section dimensions in a port to feed it at any real RPM. 315cc is a small rectangular port. Trying to feed 540" takes some airflow. It WILL be a TQ monster.....better be ready to hang on and keep it straight...and shift quickly!
A running motor creates a lot more interesting dynamics than a measly 28" of flow on a bench. What looks good on a bench doesn't always go faster.
Don't get me wrong, Tony has a great set of heads designed there and they do what they are supposed to do. Be a bolt on head for 95% of the street/race type big blocks out there.
JIM
A running motor creates a lot more interesting dynamics than a measly 28" of flow on a bench. What looks good on a bench doesn't always go faster.
Don't get me wrong, Tony has a great set of heads designed there and they do what they are supposed to do. Be a bolt on head for 95% of the street/race type big blocks out there.
JIM
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
I know that I have a lot less cubes but my 406 cam has .672 lift and on my 434 the cam has .704 lift and much more duration...
Safety Car
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From: Pettis Performance 565 with two stages of Nitrous Supply nitrous 1.082, 4.61 at 155, 7.17 at 192
He only has .600 lift.. That's very little for such big engine.. With the right cam, he could make well over 700 HP but I doubt that he has anywhere close to that with the current cam.. That cam is way too little to get anything close to it's potential out of the engine..
I know that I have a lot less cubes but my 406 cam has .672 lift and on my 434 the cam has .704 lift and much more duration...
I know that I have a lot less cubes but my 406 cam has .672 lift and on my 434 the cam has .704 lift and much more duration...
Ok, I checked, at .600 they are flowing 385 cfm on a 4.6 bore, so probably 375 cfm on a 4.5 bore.
Team Owner
Joined: Jul 2001
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
I may have been a litle generous with my guestimate of 700 hp, however you have to compare those AFR 315's at .600 lift to your small block heads at .600. Just guessing, but I'll bet those big block AFR CNC 315's are flowing over 350 cfm at .600, your small block heads won't flow that at .800. Not to mention an extra 144 cubes pulling the air fuel mixture into the cylinders.
Ok, I checked, at .600 they are flowing 385 cfm on a 4.6 bore, so probably 375 cfm on a 4.5 bore.
Ok, I checked, at .600 they are flowing 385 cfm on a 4.6 bore, so probably 375 cfm on a 4.5 bore.