460 Throttle Response - Ford Forums

Rlzegers · 10-29-2009, 10:38

Hi Guys,

I replaced my 400m engine in my 1978 Ford F350 with a 460 a few months ago and I've been happy with the results but have an interesting observation. Not long after he bought the truck new, my dad tore the 400m down and put a RV cam along with an Edelbrock SP2P intake and Holley carb. It was a major improvement! One of the biggest differences was the very quick throttle response. It also towed his fifth wheel much better. I bought the truck several years ago and replaced the tired 400m with the 460. It tows my fifth wheel much better (larger trailer than dad's) and like I said, I'm happy with it but I'm very surprised that the throttle response isn't "snappier" like the 400m was. When under a good load it just pulls and pulls as long as you keep the RPM over 1700 or so, so it's not a lugging engine. With the Lunati 00096 cam with a Weiand 8012 intake and Holley 700cfm carburator and recurved dizzy, I expected a little more "snap". It almost has the "feel" of a diesel engine.

Ron

**Paul Kane** · 10-29-2009, 23:46

Quote:

Originally Posted by Rlzegers

Hi Guys,

I replaced my 400m engine in my 1978 Ford F350 with a 460 a few months ago and I've been happy with the results but have an interesting observation. Not long after he bought the truck new, my dad tore the 400m down and put a RV cam along with an Edelbrock SP2P intake and Holley carb. It was a major improvement! One of the biggest differences was the very quick throttle response. It also towed his fifth wheel much better. I bought the truck several years ago and replaced the tired 400m with the 460. It tows my fifth wheel much better (larger trailer than dad's) and like I said, I'm happy with it but I'm very surprised that the throttle response isn't "snappier" like the 400m was. When under a good load it just pulls and pulls as long as you keep the RPM over 1700 or so, so it's not a lugging engine. With the Lunati 00096 cam with a Weiand 8012 intake and Holley 700cfm carburator and recurved dizzy, I expected a little more "snap". It almost has the "feel" of a diesel engine.

Ron

Ron,

It depends on the year of the 460, but if it is 1972 or later then you have about 7.8:1 compression ratio and that is killing "snappiness," or throttle response. Also, the Weiand 8021 is a "high rpm dual plane" and your low rpm towing engine might respond better in the lower rpm range even with the OEM iron intake, although I might consider something like an Eldelbrock Performer (not an Edlebrock Performer RPM) over the Weiand 8021 in your paticular application.

Paul

Rlzegers · 10-30-2009, 17:41

Thanks Paul for the response. It's a 1971 engine but the person I bought it from bored it +0.020" so there were new pistons and I don't know what the compression ratio of them are. The Weiand is a 8012 rather than a 8021 but I don't think there's a bunch of difference other than maybe port size. I'm thinking it might be the cam because it's power band is in the 1500-5000 RPM range, which might be higher than what dad's RV cam was. I have no idea what the specs on that cam and RV cam seems to be a pretty generic term. Like I said before it pulls very nicely and I'm a happy camper.

Ron