Ok guys. I'm in the process of swapping out my stock 1989 F250 4X$ 302 EFI for a 460 EFI that I am building from the ground up. I am ready to install my cam and my question is about cam timing. I have a Speed Pro set of timing gears that allow me to time the cam anywhere from 8 degrees BTC to 8 ATC in 2 degree increments.

My build is as follows:

460 overbored .040
TRW 2366 High compression pistons (estimate 10.5 CR)
Stock Rods
ARB Rod and Main bolts
Melling High volume oil pump
Milodon deep sum oil pan
Moroso automatic 3 qt oil accumulator
Melling MTF-3 Cam---Specs @.050 duration/timing:
204 Int 216 Exh
-5 BTC 29 ABC 44 BBC -10 ATC
Stock heads with chrome plated stainless valves stock diameters
MSD 6A ignition with Master Blaster Coil
Borland Headers
2.5 " true duals with Trush Flowmasters
Lightning Throttle Body with TransDapt spacer
Conversion from SD to MAF SEFI
All smog related equipment is verbotten (EGR, Air Pump, Catalytic converter, etc)
A9L ECM with Tweecer
E40D with Baumantor
BW 1356 Transfer Case
4.10 Sterling 10.25 Rear Axle with LockRight
4.10 Dana front axles with LockRight

I have heard that advancing the cam timing 4-8 degrees can provide some additional HP but primarily will provide low end torque (which is exactly what I want). Do I need to advance my timing at the cam, or can I just set it at 0 degrees and pick up the same advantage by advancing my distributor base timing?

Any advice or comments are welcome. Thank you!

 

Going only from only the duration figures you posted it's a awful small cam.

 

with 10.5-1 CR you might want a cam with more duration. It's gonna want to ping on pump gas..

On the bright side, with MAF you can go with a bigger cam with no problems

 

Not looking for 6000 RPM dragster here guys. Just want a good towing vehicle with decent mileage.

Everything I've read does not put me away from pump gas till I exceed 11-11.5 CR. Premium doesn't bother me as long as it will go with a load and have decent mileage.

Any ideas on the timing question?

 

Cam timing is NOT the same as ignition timing.

Points to consider...

EFI motors came with "straight up" cam timing. It was the '70's-->'87 carbed engines that were retarded for emissions.
(if in question I would ask the manufacturer of your cam)

10.5:1 is only going to work well if you have sufficient 'quench'. Was your block decked? What head gasket are you using? Etc....

I don't see where you mention what distributor you're using. But ignition timing does play a big role and for sure it will have to be tailored to your specific build.
(Re in "car" nation automotive) has some good advice on their site or Scotty can recurve a dizzy for you.

 

If you've got a good builder giving you that advice then go with it. I'm not a pro, not by a longshot. Just passing on what I've picked up while researching cam choices for my SD 460. It surprised me to see 10.5-1 CR used with a 205 @ .050 cam though. Everything I've read about towing / torque builds has me looking at about 9 to 1 with that kind of cam duration. I'm working on my 92 460 with a similar set of goals, but my shortblock only has about 18k on it so I'm not going past headwork (porting and milling) and a cam right now.

Looking to see progress and results on your build, good luck!

Oh yeah, cam advance.. The Crane tech and the Lunati tech I talked to both suggested 5-6 degrees of cam advance for the best lowend and midrange pulling power with 5000 rpm as my top end. Most of the time 4000 is as high as I rev it so my target is 1500-4500. I'm going with 207/213 @ .050 and about .490/.515 lift ground on a 114 LSA, installed at 5-6 advanced. Re in car nation is a good source for custom cams, he's done a lot of towing motors, both SD and MAF. I was surprised how little extra it costs to have a custom cam ground, $220 for a cam and lifters. $50 or so less than the Comp Cams efi cam and lifters I looked at when I first started doing my research.