Mushroom lifters – Any advice

Andrew_B

Andrew_B

Junior Member
Mushroom lifters – Any advice

I’m building a few flatheads and was thinking about installing Studebaker Champ Mushroom lifters. I have the back cutter to spot face the bottom of the lifter bore, and can machine the bronze lifter bushings. Just wonder if anyone here has built a flathead with them and has any advice or pointers in going this route.

Thanks,

Andrew
 
Re: Mushroom lifters – Any advice

Isky made some track cams 1023/1024 that used these lifters. To take advantage of them the cam should be ground for them.
 
Re: Mushroom lifters – Any advice

I agree Ron. No reason to go to the effort to install them if the cam doesn't take advantage of them. I have cam blanks that will be machined for each engine.

Andrew
 
Re: Mushroom lifters – Any advice

Back in the 50's I asked Isky why he made mushroom lifter cams for flathead Fords.
His answer, "Why did I ever do that. Big mistake."
 
Re: Mushroom lifters – Any advice

I've got some also, but never found any cam to run. Haven't really looked hard. Pete discouraged me.
 
Re: Mushroom lifters – Any advice

If the objective is maximum performance a roller cam is much better. Only during the initial .050 of valve lift does a mushroom lifter cam have a slight advantage.
 
Re: Mushroom lifters – Any advice

I've looked at the Crane roller lifters/cams but I think they require too much valve spring seat pressure for a flathead to handle and I'm sure they are not light weight. A mushroom lifter is 15 grams lighter than a hollow adjustable lifter. I'm sure the return on investment is low, but I've got the time.

Andrew
 
Re: Mushroom lifters – Any advice

Barney Navarro used them for a while and found that they have tendency to egg shape the follower bore more rapidly than the stock ones. They solve one problem but create another one.
 
Re: Mushroom lifters – Any advice

What constitutes "more valve spring seat pressure than a Flathead can handle"? Which part of a Flathead can not "handle" high seat pressure?
 
Re: Mushroom lifters – Any advice

I built a 59AB with a Craine roller cam a few yr's ago. The owner had the cam and a set of Crain dual springs. I installed one of the valve and spring set ups. It took a 10 foot bar and tender fingers to get the keepers in. I don't know what the seat pressure was but it was weaked. I finally got hold to a guy that run one of those cams in a street and drag car. He said he knew what I ment about high pressure. The first one he built only run a short time and split the block. He talked to Dave Crain, and Dave told him if anyone used one of those cams they were on ther own, there had been no testing on those cams. SO, he set the next one up with single Esky springs with 100# seat pressure and been draging it for 2 yr's with no trouble. SO, I built the one I was building that way, 3-5/16 + 4-1/8, 3 97's, ect, 37 LaSall trans, quick change. In a 35 street coupe, The guy has been running it on the street for 5 yr's and loves it. Walt
 
Re: Mushroom lifters – Any advice

JWL said:
What constitutes "more valve spring seat pressure than a Flathead can handle"? Which part of a Flathead can not "handle" high seat pressure?
Click to expand...

I would like to know that also....
I ran one with a .488 lift radius lifter cam at 200 lb. on the seat.
Worked fine.
It gets rather tiresome hearing all these BS old wives tales all the time.
 
Re: Mushroom lifters – Any advice

The Late, Great Flatdog, who put a fully streetable 3,000 pound '34 well into the 12's with a blown flathead, used that cam. He groused a lot about the sheer difficulty of compressing the springs and getting all the parts together in there... at some point the engine was torn down, and as an experiment (the skin had grown back on his hands and he wanted to keep it there, I think) he reassembled the thing using only the outer spring. No problems, no sign of float, no loss of performance measured on the strip or on his G-meter used for road testing.
 
Re: Mushroom lifters – Any advice

I have done quite a bit of research on the history of flathead cams (see http://www.tildentechnologies.com/Cams). I believe I can shed some light on the history of mushroomed and radiused lifters and why.

Despite a rather small duration, Ford was able to get good lift out of their cams by using what is called a “dwell at maximum velocity”. The radial point where the cam contacts the lifter is directly related to the velocity or rate of lift (think of it like a lever arm). I do not believe the aftermarket had the capability to use this design technique. The only way they could get more lift was to (1) increase the duration, (2) use a larger mushroom lifter, or (3) use a radiused lifter.

I have degreed several flathead cams now and have yet to find an aftermarket flathead cam with a dwell at maximum velocity. If this technique were used, I believe you could get just as good a lift curve without resorting to mushroom or radiused lifters.
 
Re: Mushroom lifters – Any advice

Hi Cartravel,

I've been to your website many times in the past, reading through the information you published on cam design and performance. Great information, but it still confuses me.

Andrew
 
Re: Mushroom lifters – Any advice

I wish I could make it easier to understand. The bottom line is that I don't believe the early aftermarket cam grinders had the sophistication to do designs with the dwell at maximum velocity. Mushroomed and radiused lifters achieve the same goal, but are more complicated.
Larry
 
Re: Mushroom lifters – Any advice

Yes, Flatdog was quit a guy, and I miss him as well. WE spent many a night BSing Flatheads, he taught me allot.
Ol' Ron
 
You must log in or register to reply here.
Back
Top