Mickey Thompson pistons

-
CrustyCuda

CrustyCuda

Member
Joined
Sep 15, 2020
Messages
9
Reaction score
2
Location
Alberta
Does anyone have any information they can share as to what application these pistons would be for. They look like old tech elevated quench pistons but I’ve been told also they’re low compression forced induction pistons. Planning to put them in a .030 over 383 but looking for some insight first.
E5780CD5-A263-43FE-9FCD-F55F88FAC7E0.jpeg
 
CrustyCuda said:
Does anyone have any information they can share as to what application these pistons would be for. They look like old tech elevated quench pistons but I’ve been told also they’re low compression forced induction pistons. Planning to put them in a .030 over 383 but looking for some insight first. View attachment 1715868127
Click to expand...

Measure the compression height and compare against a regular 383 piston. It will give you an idea about the compression in your application.
 
CrustyCuda said:
Piston measurements
4.280
.984 Pin
1.342 CD
.085 Step
Click to expand...

That would be way down on compression. How are you measuring the compression height? Did you add half the pin size in?

Stock 383 is about 1.92 compression height for whatever its worth.
 
qkcuda said:
Compression height should be around 1.9 inches for a 383.
Click to expand...
planning to put a 440 crank and 6.760 rods for a 431. the deal on these was too good to pass up regardless of the application. i just cant find any info on the pistons themselves. Mickey Thompson
 
CrustyCuda said:
planning to put a 440 crank and 6.760 rods for a 431. the deal on these was too good to pass up regardless of the application. i just cant find any info on the pistons themselves. Mickey Thompson
Click to expand...

The pin size you posted is a small block pin. BBM is 1.094 pin.
 
KB pistons for that combination are listed at 1.327 compression height, so you are in the ballpark.
 
CrustyCuda said:
planning to put a 440 crank and 6.760 rods for a 431. the deal on these was too good to pass up regardless of the application. i just cant find any info on the pistons themselves. Mickey Thompson
Click to expand...
In that application you should be very close to zero deck, a few thou.either way, depending on deck height of the block. So.....
Pretty good compression ratio, (i haven't done any calcs, w.a.g-11 to 1)will have to use open chamber heads, will have to bush the rods, and still have to use a pressed pin (no retainer grooves.)
I would also bet on a BUNCH of piston to wall clearance with those skirts. Maybe .007?
 
I googled that number and someone had a set years ago they called 426 pistons, but with that compression height they would have to be early stroker pistons. Having spent a lot of time trying to mix and match pistons myself, I admire your initiative.
 
Oh, almost forgot. With that deck height and a flat top, you'll need to cut valve reliefs In those pistons if you plan to run a cam that will work with 11, 11.5 to 1 cr.
Could always cut off the reverse dome.......
 
qkcuda said:
I googled that number and someone had a set years ago they called 426 pistons, but with that compression height they would have to be early stroker pistons. Having spent a lot of time trying to mix and match pistons myself, I admire your initiative.
Click to expand...
If they were standard bore, with a 440 crank they would be 426 cu in. Same b&s as a hemi.
 
33IMP said:
In that application you should be very close to zero deck, a few thou.either way, depending on deck height of the block. So.....
Pretty good compression ratio, (i haven't done any calcs, w.a.g-11 to 1)will have to use open chamber heads, will have to bush the rods, and still have to use a pressed pin (no retainer grooves.)
I would also bet on a BUNCH of piston to wall clearance with those skirts. Maybe .007?
Click to expand...
Depends on the alloy .007 seems like a extra ton of room
 
MOPARMAGA said:
Depends on the alloy .007 seems like a extra ton of room
Click to expand...
1WildRT said:
.007 was pretty common back in the day... Without expanders or trick alloys particularly if used hard pistons expand allot...
Click to expand...
Who knows? I'm sure that's why the op is looking for info.
Full skirt. How much ovality? How much barrel? More measurements are required to make an educated guess.
I took out an ancient set of full skirt pistons like those from a maxwedge that was running OVER .010 p to w. (.060 over)
I honed it a little, and put standard 440 pistons in it (.070).
I would not run those M/T pistons any less than .005.
 
33IMP said:
Who knows? I'm sure that's why the op is looking for info.
Full skirt. How much ovality? How much barrel? More measurements are required to make an educated guess.
I took out an ancient set of full skirt pistons like those from a maxwedge that was running OVER .010 p to w. (.060 over)
I honed it a little, and put standard 440 pistons in it (.070).
I would not run those M/T pistons any less than .005.
Click to expand...
Yeah, I agree the more I think about it you're right
 
.007 isn’t much for that piston. I think MT had those pistons made by Jahns. Or however they spelled it. I’d use them. I’d just make damn sure the cylinder finish has enough oil to lube those skirts with that finish on them. Even with .007 cold you won’t have that much at temp. You’ve got to have some oil on the skirts or they will grab the bore.
 
You must log in or register to reply here.
-

Back
Top