Speedmaster Rods, can i trust them?

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And as always, have all of them checked. "Out of the box" can bite you in the butt.
Definitely, clean check repeat, and to add to that ive never seen an "out of the box" set of heads thats ready to bolt on, if nothing else they have metal chips down in them someplace, one set i saw had chips under the valve spring shims
 
And as always, have all of them checked. "Out of the box" can bite you in the butt.
I did that on my current 340. I built it about 25 years ago, and it still runs great. I built a several motors before that, and I never checked anything. If the machine shop said the bores were 0.030 over and the crank was 0.010 0.010, I just bought 0.030 pistons and rings and bearings. Then I put things together without checking anything. I guess I was lucky?
 
I did that on my current 340. I built it about 25 years ago, and it still runs great. I built a several motors before that, and I never checked anything. If the machine shop said the bores were 0.030 over and the crank was 0.010 0.010, I just bought 0.030 pistons and rings and bearings. Then I put things together without checking anything. I guess I was lucky?
Yes you were
 
I wouldn't hesitate to use those rods.
I grind three reliefs on the rod's big end chamfer on every engine I build on V engines, where the rods are paired. If one rod gets trapped against the crank cheek, it's oil can escape & fresh oil can enter the journal.
That metal is extremely tough when grinding it & you really notice the difference, compared to how easy it is to grind factory rods.
 
I did that on my current 340. I built it about 25 years ago, and it still runs great. I built a several motors before that, and I never checked anything. If the machine shop said the bores were 0.030 over and the crank was 0.010 0.010, I just bought 0.030 pistons and rings and bearings. Then I put things together without checking anything. I guess I was lucky?
If you had all your parts at a good machine shop they probably measured everything for you and made sure you weren't gonna have any issues, but its still important to check bearing clearance with plasti-gauge if nothing else, because people do make mistakes, especially nowadays with all the defective part issues going around
 
Don't want to hurt any feelings but SM rods, Eagle crank, heavy TRW slugs, obsolete Mopar cam... are all on my Do Not Fly list.
 
Don't want to hurt any feelings but SM rods, Eagle crank, heavy TRW slugs, obsolete Mopar cam... are all on my Do Not Fly list.

Do you think SM has their own foundry in China....that foundry probably makes many different brands of steel rods....Eagle...Scat...K1...and so on...
I have run both Hughes fast rate cams and "old" mopar cams....the MP590 is just as fast as Hughes 6064....MP cam 10.66...Hughes 10.65 in Bakersfield....Mp cam 10.78 in Vegas ..Hughes 10.79 in Vegas...same car...same engine...

Post your camshaft comparison ?

Current 71 Dart has "old" MP590 cam in the 360....10.38 @ 126.06 ....with Speedmaster heads...
 
Don't want to hurt any feelings but SM rods, Eagle crank, heavy TRW slugs, obsolete Mopar cam... are all on my Do Not Fly list.
Kind of agree. But, new quality rods $800-1000, new 4340 crank $1000, nice light new pistons $800, new solid cam and lifters $500, and might make what? 25 more horsepower? 50?
For $3300, I'd run what I already have in my garage.
 
Do you think SM has their own foundry in China....that foundry probably makes many different brands of steel rods....Eagle...Scat...K1...and so on...
I have run both Hughes fast rate cams and "old" mopar cams....the MP590 is just as fast as Hughes 6064....MP cam 10.66...Hughes 10.65 in Bakersfield....Mp cam 10.78 in Vegas ..Hughes 10.79 in Vegas...same car...same engine...

Post your camshaft comparison ?

Current 71 Dart has "old" MP590 cam in the 360....10.38 @ 126.06 ....with Speedmaster heads...
And i guarantee that my "outdated" MP590 camshaft kit isnt gonna lifter issues like everyone has been having lately due to the poor lifter hardening thats been going around
 
And i guarantee that my "outdated" MP590 camshaft kit isnt gonna lifter issues like everyone has been having lately due to the poor lifter hardening thats been going around

I am building the same 340 that you listing off, except i have Scat rods, it is just stuff i had laying around and we are going to put it together and see how it runs.
 
Yea, i think all the rods are pretty much forged in the same place anymore, i will say these look really nice actually, and they all weigh exactly the same, i think where they cheep out is the rod bolts, they dont use ARP bolts and they dont give much much info on what they do use, the least we would do is use ARP bolts and have the rods checked and resized if needed

View attachment 1715810191

View attachment 1715810192

ARP hardware and have a trusted local shop check them!
 
I did that on my current 340. I built it about 25 years ago, and it still runs great. I built a several motors before that, and I never checked anything. If the machine shop said the bores were 0.030 over and the crank was 0.010 0.010, I just bought 0.030 pistons and rings and bearings. Then I put things together without checking anything. I guess I was lucky?
The machine shop bored and honed your block with out having the pistons first? Not a good idea as piston diameter and compression height vary from piston to piston. Without ?the pistons how can they bore / hone the bores accurately? I've never had or heard of a machine shop boring a block like that.
 
Do you think SM has their own foundry in China....that foundry probably makes many different brands of steel rods....Eagle...Scat...K1...and so on...
I have run both Hughes fast rate cams and "old" mopar cams....the MP590 is just as fast as Hughes 6064....MP cam 10.66...Hughes 10.65 in Bakersfield....Mp cam 10.78 in Vegas ..Hughes 10.79 in Vegas...same car...same engine...

Post your camshaft comparison ?

Current 71 Dart has "old" MP590 cam in the 360....10.38 @ 126.06 ....with Speedmaster heads...
With your SM rods did you use the bolts they gave you or upgrade to ARP?
 
Used the rod bolts that came with them....not spinning this thing to the moon...lol
 
The machine shop bored and honed your block with out having the pistons first? Not a good idea as piston diameter and compression height vary from piston to piston. Without ?the pistons how can they bore / hone the bores accurately? I've never had or heard of a machine shop boring a block like that.
agreed, the guy i use always wants the pistons and hones each bore to it's own piston and marks them accordingly.
neil.
 
agreed, the guy i use always wants the pistons and hones each bore to it's own piston and marks them accordingly.
neil.
That's the best way to have a block bored and honed. Also, I think it's a good idea to leave the torque plates on while the ring end gaps are checked. When I would look for a machine shop I would see how clean and organized they are, name brand of machines they used and then how long it would take to have the work done and also I'd check out their reputation. One thing that i know for sure is that cheaper is not always better.
 
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