Valvetrain Questions

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Aug 23, 2001 | 01:05 AM

79F2504x4

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Senior User

Joined: Aug 2001

Posts: 213

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From: Six Shooter Junction

Valvetrain Questions

[font size="1" color="#FF0000"]LAST EDITED ON 23-Aug-01 AT 02:11 AM (EST)[/font][p]I have a 71 460. I was wondering if the valvetrain can handle a cam with a profile like Lunati's 00096 Grind. I had a friend tell me i would float the valves with a cam like that. Just want to know if i need new springs valves and pushrods. Have to to college so wont be building motor up till christmas so i have some time for research. I like to make sure everything is going to work before i try it. I also would like to know the profile numbers for my stock cam and if there is a web site or book for finding these numbers.
Thanks
Chase
P.S. Does any body know the stock horsepower and torque ratings for a 71 460 and if so, at what rpm's.

1979 F-250 4x4
460 Holley650, MSD OFFROAD, Flex-a-lite fan
C6-B&M Transpack
Dana HD44Front/60Rear 3.73 Limited Slip
35 inch Goodyear Implement Tires
4 inch Skyjacker System

Aug 23, 2001 | 07:05 AM

DeenHylton

Elder User

Joined: Jan 2000

Posts: 966

Likes: 2

From: Crooked River Ranch, OR

Valvetrain Questions

Your stock valves will be fine under 6,000 RPM but you will need to buy new lifters plus springs that are matched for the cam, your stock springs will coil-bind with that high of lift.
To get full benefit of the new cam you'll also need to up-size that 650 to a 750-800 CFM carb ( I'd stick with a vacuum secondary). I would also purchase a slightly higher stall converter, somewhere around 1,500-1,800 stall.

Deen Hylton
Ford F250 460 C-6, K&N, Headers, Dual Exh.,Comp. Cams,Shift Kit
Pioneer CD w/Bose Speakers.
Other Passion: Blown 77 Corvette (Sorry Guys/Gals)
How I can afford to Drive the above: 93 GEO Metro

Aug 24, 2001 | 10:23 AM

jim henderson

Postmaster

Joined: Mar 2001

Posts: 4,968

Likes: 3

From: So Cal

Valvetrain Questions

One recommendation...

If you plan to run at an RPM above say 5,000, I have read on this digest that you should have some bottom end work done on the 460. The 460 rods have a problem with higher RPMs, so I have read. I know my 94 stock 460 doesn't make any power above about 4,500RPM(probably due to cam and intake etc) mine just thrashes, so I would guess the engine wasn't designed with high RPM in mind in stock condition.

Don't know if this is true but makes sense since it is after all, a truck engine.

Good Luck,

Jim Henderson

Aug 24, 2001 | 07:28 PM

proud owner

Mountain Pass

Joined: Jan 2001

Posts: 229

Likes: 0

Valvetrain Questions

Correct.
The rods have the tendancy to ummm, yea... SEPARATE at the caps. The rod bolts give way and there it goes!! If you plan to run better than 5000rpm, invest in some good (ARP Pro) rod bolts. The rods themselves are good to 6000, but yea..

J/.c

1965 Ford Galaxie 500 (okay, so not quite a truck)
460/C6 transplant @ 389hp/491 lb.ft.
14.29@103.8, 13-14 mpg heheheheheh

Aug 24, 2001 | 07:36 PM

proud owner

Mountain Pass

Joined: Jan 2001

Posts: 229

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Valvetrain Questions

You will have to find the right height and pressure springs for that cam. Without a higher pressure spring, you will float the valves.
By the way... your 71 460 is approx 350 horsepower and 450 lbft torque stock... plus or minus some.

J/.c

1965 Ford Galaxie 500 (okay, so not quite a truck)
ANOTHER 460/C6 @ 365hp/519 lb.ft.
14.36@100.4, 16-18 mpg AHHAAAHAAAHAAA!

Aug 24, 2001 | 08:25 PM

79F2504x4

Thread Starter

Senior User

Joined: Aug 2001

Posts: 213

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From: Six Shooter Junction

Valvetrain Questions

Thats what i figured about the valve spirngs. Does any one know what would be the best springs for my application.

I found a book in my garage that has most the info on certain motors from 71-77. It says my 460 has 365hp@4600rpm and 500FtPT@2800rpm.

Thats more than i expected, but the gas was way better back then to.
Thanks
Chase

1979 F-250 4x4
460 Holley650, MSD OFFROAD, Flex-a-lite fan
C6-B&M Transpack
Dana HD44Front/60Rear 3.73 Limited Slip
35 inch Goodyear Implement Tires
4 inch Skyjacker System

Aug 25, 2001 | 03:08 AM

cobrajet

Tuned

Joined: Feb 2000

Posts: 309

Likes: 0

From: michigan

Valvetrain Questions

alot of the cam manufactures sell the cam and the springs and other components as a matched set this way everything will work great together. if your going that far, in my opinion i sure wouldn't have all this work done and have a weak link in the system like the stock valves especially if you want to see 6,000 r.p.m.'s.. that's just that ,, there stock valves! especially too since with a more agressive cam the seat pressures are going to be greatly increased, like if your spring set comes with dampers to go with the springs, or even dual valve springs. it's up to ya, but that's just my 2 cents. see ya all later. C.J. ......................