Thread: not too happy!

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I have had my 1977 F-150,(460) completly redone everything inside is new except the crank, just needed to be polished,the cam(comp cam) is the biggest you can use with a stock torque convertor,stock heads,airgap intake,Holly street avenger 670 cfm,long headers/dual exhaust,stock distributor,roller rockers,C6 tranny,3:50 rear gears with 235x75x15 tires.I set the timming @ 12 btc.My problem is that I have a 74 f-100 stock 460 except for the 4Bbl and headers,350 gears,same tire size, when I drop the tranny in low hit the gas the tires smoke all through low gear.When I drop the built(mild) 460 into low hit the gas it won`t even break the tires loose.If I break torque the 77 it still does not have the power to break the tires loose.It is not exactly a pig but the stock 460 will show me its tail lights.I put more than a few dollars into this 77F-150 and the stock (except for the headers)74 460 beats me home every time....anyone with any ideas.Thanks in advance!

eht nailicis

A bit more information on the heads and cam would help...cam specs along with casting number and mods done on the heads. What pistons and what compression ratio?

Thanks for the reply Dave,I have all that info but in my desk @ work so I will send the specs on Friday. Again I appreciate the reply!!!

eht

I'm thinking a little under carbed, but if it won't break loose 235/75's it could be a torque converter problem. My mild 360/390 73 F100 Edlebrock intake, 600 holley, and hedman headers would smoke 31 15's.
BTW, I like your handle.

I'm thinking that torque convertor won't let the rpms come up high enough to get into the range where the cam is working. Every part you add affects all the other parts, so it just could be that your cam has taken away your bottom end. I'd get it on a chassis dyno and see what's what.

Don

I concur with Don - the stock converter probably locks below 2000 - well before the cam is starting to come alive. Depending on the cam specs, you may be 500 - 1000 shy on the converter stall speed. Even though the cam is the "biggest you can use with a stock torque converter" it would be interesting to know where (what RPM) the power starts.

Post the numbers and I'm sure you'll get some reasonable ideas!

Welcome to CHR,

Regards,
Glenn

Not enough gear for the cam.

Not enough ignition timing for the cam.

Not enough converter for the cam.

Not enough head for the cam.

Not enough intake manifold. Any carbureted street motor built today will benefit from a high-rise, dual-plane intake such as an Edelbrock RPM or Weiand Stealth intake manifold. They advertise making power from 1500 to 6500 and are the best street manifold you can bolt onto a street motor in my opinion. They will make around 40 hp more than a low-rise intake and will make it where you can use it on the street.

Too much cam for the available static compression ratio. Compression does not begin in the cylinder until the intake valve closes with the piston coming up the bore on the compression stroke. If the motor is light on static compression ratio and you install a cam that delays the intake closing point of the intake valve, some of the charge can be blown back up the intake tract through the still-open intake valve. Choosing a camshaft that will perform correctly is quite a juggling act when building a motor and too much or too little cam for the available static compression ratio can make or kill the combination.

Beginning in 1972, Ford began using timing chain sets that retarded the camshaft timing by up to 8 degrees in order to bring the motors into compliance with ever-more-stringent emissions laws. You may have inadvertantly installed one of these retarded timing sets in the motor and you would not have caught it if you didn't degree the camshaft upon installation. Retarding the cam will add to the top end performance while decreasing the bottom end "snappiness" of the motor.

For the benefit of you newbies out there, yes there is ignition timing and there is camshaft timing. Do not confuse the two. Ignition timing has to do with where the spark plug fires in relation to the piston position in the bore. Camshaft timing has to do with opening and closing of the valves in relation to the piston position in the bore.

Thanks techinspector1,your input is appreciated.I normally do most of my own work but have become somewhat disabled so I had a speed shop do the work and I went along with his combining of parts...airgap performer intake,670 cfm Holly,hedman headers etc. but what gets me is that my stock 77 460 (other than 650 Holly on stock intake and headers) same gears and tires blows by me at least from light to light.I have a Accel dist.I will be putting in soon and without going "ALL OUT" what do you think as to the torque convertor. I do pull a RV with this truck as I do with my stock 74 f-100 460.
Thanks again,glad I joined....
eht

Just want to thank all who cared enough to try and get me going forward. Thanks to all who replied!!!

Eht

Richard is right, I forgot all about that retarded timing chain setup. That could be one major contributor, along with some other components not working well together (cam, stall speed, high gear ratio). 460's ae generally torque monsters, so something isn't letting it do it's thing. Get those cam specs if you can, it will help.


Don

I know what changing the timing set did for a '76 F250/460. It took a California spec truck that was a major dog into another performance world. Of course two grocery bags of CA. required pollution control crap went with it as well. A 780 cfm 3310 Holley helped a wee bit too