Mustang Tech

Thanks for your input Jacko but it's not just a little tappet noise. It's every rocker that's making a racket.

I once used some cheap proform rollers on a stocker, thinking it would be better than the stamped steel rockers when we changed a stock hydro cam (non roller)... I had two rockers that insisted on chattering.

Rotating the engine over by hand with covers off I was able to identify the offenders, but by pure fluke I rotated the engine backwards to try and see what was going on and the pushrod magically seated to the rocker after that?

Not sure why but after that I they didn't chatter until I didn't use the engine for a while. Once the lifters leaked down they chattered again. I ended up replacing all the pushrods in that case which solved the problem, but only did that is it was the cheapest form of elimination...


Charlie

some rockers will touch the spring retainers

Nuts wrote:Thanks for your input Jacko but it's not just a little tappet noise. It's every rocker that's making a racket.

in that case it is more fundamental then; eg pushrod length or primary oil gallery issue

No interference Shaun. Pushrod length is spot on Jacko. Going to yank the manifold and have a good looksee.

Any wiser Nuts?

On to a few urgent jobs. I'll get back to it when I have nothing else to do.. I need break from it

Ok here's an update for you.. Problem was the Ford Racing Lifters just weren't up to the task. Switched to a set of Comp Cams 851 short travel lifters. Problem solved! Quiet as a mouse now. Owner very happy as he picked up best modified XL at the falcon nations recently!

Nuts wrote:Ok here's an update for you.. Problem was the Ford Racing Lifters just weren't up to the task. Switched to a set of Comp Cams 851 short travel lifters. Problem solved! Quiet as a mouse now. Owner very happy as he picked up best modified XL at the falcon nations recently!

Howards are about the best I've found, Ive had the comp cam break the push rod seats, but they were magnums not short travel, the short travel are a better lifter. The Howard Maximum effort are a real good lifter, but even the normal ones are pretty good.

I used the Eaton ones in my 347. They seem to be working well.

It would appear that it all boils down to valve springs and cam. Although the cam profile is almost identical to my engine, the valve springs are very different. I'm using the stock springs that came with the edelbrock performers. Probably good for 6.5k. Pete is using AFR heads with much stronger springs and designed to rev all day at 8k.

Nuts wrote:It would appear that it all boils down to valve springs and cam. Although the cam profile is almost identical to my engine, the valve springs are very different. I'm using the stock springs that came with the edelbrock performers. Probably good for 6.5k. Pete is using AFR heads with much stronger springs and designed to rev all day at 8k.

AFR's come with a roller spring, 185 are good for mid 6000k, the 195 heads have Pac racing HR spring thats good for 7200, the bigger heads use a solid roller spring which are about 250 on the seat.

Shaunp wrote:

Nuts wrote:It would appear that it all boils down to valve springs and cam. Although the cam profile is almost identical to my engine, the valve springs are very different. I'm using the stock springs that came with the edelbrock performers. Probably good for 6.5k. Pete is using AFR heads with much stronger springs and designed to rev all day at 8k.

AFR's come with a roller spring, 185 are good for mid 6000k, the 195 heads have Pac racing HR spring thats good for 7200, the bigger heads use a solid roller spring which are about 250 on the seat.

These are 205's and not sure what springs are fitted but I had to upgrade my valve spring compressor so I could compress the springs.

They will be a Pac racing spring 220 on the seat they are really a solid roller spring and should be swapped out on HR they put a heap of load on everything and just wear stuff out.

Thanks for that Shaunp. I'll pull one set and measure them when I get the car back. Could explain a few things..