SBM "MagnaVelocity" mushroom camshaft.

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Bighead440

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Just curious if anyone here has ever run or had experience with the only (to my knowledge) Direct Connection mushroom cam offered for small block engines? It's specs are pretty formidable, 324 duration with .633" lift (1.5 rockers) and a 110*LSA. The Mopar Performance books never mention it, but the old DC bulletins list it for NASCAR Grand National use on long tracks and other 355" Kit Car applications. I want to build a 4" crank SB with high compression and W2 heads for a nostalgia build in a really light chassis, possibly manual trans, and I think this might fit the build. I have a new set with lifters, and means to bronze bush the lifter bores, or the tube/peen kit to block the galleys. Any info or thoughts?
 
I don’t know about that cam in a lightweight drag car but the lifters are worth gold. I’m always on the lookout for a set but can never find them.

If the info you have doesn’t list the .050 number the only way I know to get that for one of theses cams is to multiply the advertised duration by .85 and Chrysler says that’s the number.

If that’s the case that’s a really slow lobe.
 
I don’t know about that cam in a lightweight drag car but the lifters are worth gold. I’m always on the lookout for a set but can never find them.

If the info you have doesn’t list the .050 number the only way I know to get that for one of theses cams is to multiply the advertised duration by .85 and Chrysler says that’s the number.

If that’s the case that’s a really slow lobe.
I think this one is around 290* @.050, based on lobe specs from REED, Racer Brown and Lunati for their 1.00" lifter mushroom cams. More rate-of-lift than just about any .904" cams that live and don't eat valvesprings.
 
I don’t know about that cam in a lightweight drag car but the lifters are worth gold. I’m always on the lookout for a set but can never find them.

If the info you have doesn’t list the .050 number the only way I know to get that for one of theses cams is to multiply the advertised duration by .85 and Chrysler says that’s the number.

If that’s the case that’s a really slow lobe.
OH, and I also need one (1) mushroom lifter to complete a set of 15 that I have.
 
Have you looked into this one from Schneider?
I talked to Jerry and Kevin about it, the Mini-Express was never a SB cam, so IDK what they started with, but it maps-out to the same lobe as the BB "M-E" cam. The BBs were ground on a 107LSA and I had them grind me one on a 106LSA. The Magna-Velocity is on a 110LSA, and has more duration, so I thought the Mini-Express might be worth a try in a SBM.
 
That’s incorrect, there was a SB mini express cam.
I’ll find the part number in a minute….
 
That’s incorrect, there was a SB mini express cam.
I’ll find the part number in a minute….
I see a part# P3690589 according to the old SA Design “Mopar Performance” book on the parts outline page they list it as “Magna-Velocity” with 324° duration and .670” lift for the SB. The RB section shows P3690588 with 332° duration and .695" lift which is referred to as “Super-stock” I can’t recall when the Mini-Express was offered, maybe in the early 80’s??
 
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I have been searching and have come up empty!

Uuuurrrrrrgggggghhhhhh!!!!

I give up for now and may return to post what I’m sure I have seen but can’t find. It was an older cam list I believe.

I think I know where you got that from though!!!!

Presented by Chrysler Corp. 1980!
(I love the mention of who’s cam there ground at. Cam Dynamics, Racer Brown, Crane….)

61E93727-5E57-44A5-8693-E5D154459A53.jpeg
 
That P3690589 is the 324deg./.633"-110 cam the PO is referring to, not sure if I've seen a mini-express SB cam listed anywhere.
 
with easily available mechanical roller cams, can’t say as I can figure out any logical reason these days of going down the mushroom road.
 
with easily available mechanical roller cams, can’t say as I can figure out any logical reason these days of going down the mushroom road.

Expense. If I could find a set of mushroom lifters I’d have zero issues running .750 gross lift. I would never try that with a .904 lifter.
 
Finding the mushroom lifter is the issue.
If you already have the cam and all you need is the lifter, I’d search for the lifters. Hens teeth
 
Well, Schneider "says" they have a "Mini Express" mushroom cam for a small block. BUT reading between the lines I THINK what they mean is they have a .903 lifter diameter "equivalent" camshaft, because they list shroom lifters nowhere. You might try calling them and see what they say if you have not already, @Bighead440 .
 
Well, Schneider "says" they have a "Mini Express" mushroom cam for a small block. BUT reading between the lines I THINK what they mean is they have a .903 lifter diameter "equivalent" camshaft, because they list shroom lifters nowhere. You might try calling them and see what they say if you have not already, @Bighead440 .
They say on their site that it requires the special lifters with a 1.00" foot. When I ordered my custom Mini Express (?) from Kevin Cantrell, he reiterated that to me, as did Jerry. Mine is on a 106LSA.
 
They say on their site that it requires the special lifters with a 1.00" foot. When I ordered my custom Mini Express (?) from Kevin Cantrell, he reiterated that to me, as did Jerry. Mine is on a 106LSA.
I wonder why they don't show lifters? Do they just not offer them? That's like buyin a hooker that won't put out.
 
I don't usually hang out in the smallblock forum ;) so I just came across this thread.

Back in 2019 or 2020, I had Schneider regrind my (B/RB) Mini-Express because some of the lifters weren't turning. They saved the lobe profile in their library and said they could make them on request. It does appear on their website as a LA cam (M-316F) which 12many linked in post #5.

Anyway it was originally [email protected] with .654 lift, now it's [email protected] with .652. It works great in my 451, but it'll be a whole lot of cam for a smallblock even if stroked to 408...
 
I have no experience with the whole mushroom lifter deal but this thread coming around again got me wondering; does anyone know if a "custom" lifter can be made to mushroom lifter specs? Seams like there must be a way to have them made. I know Trend offers tool steel lifters so it makes me wonder if they would make a set if someone really wanted them. Of course, I assume it is likely not a cost effective deal.
 
The mushroom lifter goes back decades, a poor man's roller. There were only solid roller lifters then, not hyd available.
Do not see a mushroom cam + lifters as a cost effective deal, nor giving as much power as a roller using the aggressive lobes now available.
 
Poor mans....ah, whatever. Good grief :rolleyes:

Im sure many builders here who’ve been around a while know why the mushroom lifter cams “as being discussed” came to be with Mopar.

Here’s a quote (from another forum) from someone out of Concord, NC who was involved in NASCAR:

“You are correct. I am a retired NASCAR engine builder, 28 years building engines for Hendrick Motorsports. I was hired in 1993 by Randy Dorton to become HMS Engines 4th engine builder. I got my start in the late seventies helping build engines for a couple of the smaller Chrysler teams. At that time all NASCAR Winston Cup Grand National Teams were just a few years in trying to make the smaller 357 engines work after NASCAR banned Hemi's and Big Blocks. We used the mushroom tappet cams because at that time roller cams were not permitted mainly because good roller lifters which could endure 500 miles of 200mph racing at high RPM and high valve spring loads without breaking could not be found. Mushroom cams allowed for a more aggressive profile to be run over a conventional flat tappet grind”

Plenty of other info-knowledge out there as well.
 
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Shrooms date WAY back in industrial and heavy truck stuff. We had a forklift project in high school auto shop with a Perkins diesel 4cyl that had shroom lifters. Sent them out locally and had them refaced.
 
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