[Mustangsaly]

I have a Chevy 350cid 1996 to 2000 5.7 Stock Rod Question,

I'm building a 400HP (Build/Dyno sheets say 420HP) out of a 1 piece rear main 4 bolt vortec block using vortec heads. I have the heads and a 2 bolt 1 piece rear main block now, but I've found a 4 bolt main 350cid 1998 vortec long block that run when heads were pulled and sold (long block is from a HS friend in the office of a salvage yard) I can buy the 4 bolt main 350cid 1998 vortec long block for $200 and I'm after the block & rods. is $200 a fair price for a 4 bolt main 350cid 1998 vortec long block ?

I know the rod question has been gone over, but in your opinion is the stock GM 1998 350 5.7 rods worth reconditioning ? I won't use the pistons or crank, just the block & rods, if the stock GM rods are good quality.




Mustangsaly

 

[Mustangsaly]

*Bump*




I ask cause they look smooth & shot peeded factory.......





Mustangsaly

 

[jimfulco]

That's because they're made from powdered metal. Pressed into shape and cooked, kinda like lunch meat. Scoggin-Dickey says they're good for up to 500hp.

http://www.sdpc2000.com/catalog/389/products/478/5700-PM-Connecting-Rods.htm

 

[Mustangsaly]

theres a thread on here by a performance engine builder not to far back that says PM rods are not strong enough for performance applications, and to stay away from them.


http://www.hotrodders.com/forum/350-crank-rods-question-101523.html





Mustangsaly

 

[327NUT]

You know all the new chevy engines use the PM rod, even the hipo crate engines. But the mere thought of "powdered metal" would just scare the hell out of me when I got on that thing. Theres just too many early GM forgings out there waiting to be rebuilt. I read an article "Exposing the Pink rod myth" which basically said that all chevy rods were forged from 1038 steel (except the aftermarket Bowtie which is forged from 4340) and the only difference the Pink rod had was that it got mag,d and shot peened from the factory, then got the infamous pink paint splashed on it. Also noted was that starting in '89 for some reason GM decreased the section width of the small block rod from 0.570 to 0.505. So I would look for an early set, have them mag'd, polish the beams, shot peen and install ARP bolts and resize and you'll be good to go.

 

[CNC BLOCKS NE]

The rods before the PM rods are the better rods as there is much more material around the rod bolts compared to the earlier rods with the small stamp pad on the side and the later rods may have a narrow beam but in the center where its thinner the beam actually gets thicker as you get closer to the big end of the rod making it a much better peice there is a reason GM redesigned those rods in the early 80's

 

[Mustangsaly]

so the rods in the 1986 block I have would be a much better rod to recondition than the PM rods in the 98 vortec block ?

this makes it sound like the PM Rods are the cats meow,and the new pink rod. and the PMs come at a bigger price that scat I beams.
http://www.sdpc2000.com/catalog/389/products/478/5700-PM-Connecting-Rods.htm


as a electrician I did a job at a monore factory ( they make monore shocks & rancho shocks ect. at this plant) but they had machines that stamped out a round washer looking piece with ridges on it, it was stamped out of power medal, the power kinda reminded me of a graphite powder, then they dumped the stamped piece on a steel chain type conveyor belt that took the pieces through a oven (not sure how hot it heated them but it was hot, and you could see a huge flame in the oven the pieces passed over) this piece was the size of a nickle and about as thick as a nickel with 3 ridges on it to make it stronger. it came out of the oven and cooled and then was rock hard. this piece goes in the shock tube and the chrome shock rod goes through this piece. the only powder forging I've ever seen in person.




Mustangsaly

 

[automotive breath]

I have a Chevy 350cid 1996 to 2000 5.7 Stock Rod Question,

I'm building a 400HP....

At 400 HP...

PM rods will work just fine

86' rods are even better

Early truck X rods are the best

 

[Mustangsaly]

is it cheaper to recondition & shot peeded and polish the beams and install arp fasteners on stock rods and would stock rods make better rods than buying new $200 scat I beams ?






Mustangsaly

 

[machine shop tom]

is it cheaper to recondition & shot peeded and polish the beams and install arp fasteners on stock rods and would stock rods make better rods than buying new $200 scat I beams ?
Mustangsaly

The 200 buck Scat I-beams would be a better choice than either of the stock pieces, especially if you were using floated pins.

tom

 

[automotive breath]

Tom gives good advise, why spend a lot of money on old rods when you can buy a new set for $200?

 

[machine shop tom]

Tom gives good advise, why spend a lot of money on old rods when you can buy a new set for $200?

Here are some pricing examples:

Recon stock rods, adding ARP bolts: $165
Polishing and bushing, more $$

Scat stock replacement I-beams (pressed): $225
Scat stock replacement I-beams (bushed): $240

Stronger rods will of course cost more, but we are talking stock rods here, and these Scat pieces are a little stronger than stock Chevy.

tom

 

[automotive breath]

Any opinion on the Eagle SIR rod, I see a lot of people buying them for about the same price.

 

[machine shop tom]

Any opinion on the Eagle SIR rod, I see a lot of people buying them for about the same price.

I do NOT recommend them. They will not hold shape when the big end is torqued to the proper stretch. I have re-sized them after stretching the bolts to spec. But after disassembly and reassembly and torquing, they go .002" (or more) out-of-round.

The Scats are better.

tom

 

[automotive breath]

Thanks, I’ll avoid them like the plague.

 

[Mustangsaly]

yes I was hoping to hear from Tom, I respect his opinion. Tom what about the $200 1998 vortec 4 bolt long block ? good 450HP block ? good buy ? it's a complete long block thats why I was asking about using the PM rods or using the 1986 stock stock rods.






Mustangsaly

 

[CNC BLOCKS NE]

I do NOT recommend them. They will not hold shape when the big end is torqued to the proper stretch. I have re-sized them after stretching the bolts to spec. But after disassembly and reassembly and torquing, they go .002" (or more) out-of-round.

The Scats are better.

tom

I agree with Tom as we have not seen any good Sir rods from Eagle as they are still having problems with there rods.

We don't build many stock type engines but if we do we have used the Scat rods with the 7/16 rod bolts and so far no issues.

 

[Mustangsaly]

I agree with Tom as we have not seen any good Sir rods from Eagle as they are still having problems with there rods.

We don't build many stock type engines but if we do we have used the Scat rods with the 7/16 rod bolts and so far no issues.

Thanks CNC Blocks N/E,

nothing like real hands on experience from a machine shop/builders. it's greatly appreciated ! your guys advice is a tad better than the advice from a guy I know that his uncles brothers friend said this or that was good or bad .






Thanks Guys



Mustangsaly

 

[CNC BLOCKS NE]

Thanks CNC Blocks N/E,

nothing like real hands on experience from a machine shop/builders. it's greatly appreciated ! your guys advice is a tad better than the advice from a guy I know that his uncles brothers friend said this or that was good or bad .
Thanks Guys
Mustangsaly

I hear that, Or when someone bases there info on one engine they have had for 4 years or so or one set of rods or one set of pistons ETC. as we have been doing this performance work for 33 years now and we try to base our info on many engines,blocks,rods,pistons ETC.

 

[Mustangsaly]

I hear that, Or when someone bases there info on one engine they have had for 4 years or so or one set of rods or one set of pistons ETC. as we have been doing this performance work for 33 years now and we try to base our info on many engines,blocks,rods,pistons ETC.

So true, I hate having the GM rods and not using them. but for the money I can't see any other way. I will have more questions B4 all the motor parts are bought or B4 the motor is built,



thanks




Mustangsaly