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Author Topic:   GM Connecting Rods
fast40
Dirt Roller

Total posts: 10
posted July 29, 2004 08:31 PM  
I'm trying to put together a low budget bomber/enduro motor. I've secured a good 010 block and a set of hyperutectic flatops from online auctions. I'm now looking for a set of used rods. Can anyone explain to me the difference between GM Powder rods, GM Pink Rods, GM "X" rods and GM "O" rods. Any help on which would be the wiser choice would be much appreciated. Thanx

racer17j
Dirt Forum Champ
Total posts: 5390
posted July 29, 2004 10:19 PM  
Thanks Racer17j. the PTM site offers seven different choices for reconditioned GM rods starting at 99.95 .If nothing better comes along I will probably go with those. Their top of the line recon. rods are re-worked "X" rods so they must be good. I still would like to know what the difference is between the "Pinks", "Powders", "X"s, and the"O"s. Any help would be appreciated.

iowatoolman
Dirt Freak

Total posts: 369
posted July 30, 2004 12:11 AM  
nothing much really they are all made the same. some are hand selected for perfection but that is someone standing on the assembly line just grabbing rods out of the pile
i would suggest a set of eagle 4130 sir rods they are stronger than any stock rod and not to expensive (considering arp bolts and they are new) usually about 200 sometimes you can find them cheaper

rico 08
Dirt Forum Champ
Total posts: 1139
posted July 30, 2004 06:37 AM  
o rods are lightweight but supposedly strong
X rods are heavy but supposedly not any stronger
PM rods are supposedly stronger than either

Just a thought...i spent $219 reconditioning my X rods,they have arp's but i think next time i'll try a scat rod...maybe

fast40
Dirt Roller

Total posts: 10
posted August 02, 2004 10:20 PM  
Just came upon the opportunity to buy a set of Summit Stage II rods with two seasons on them for sixty bucks. Dont know much about them other than they have ARP bolts and go for about $350. a set new. Also, on a different subject, this weekend I found a set of 487X heads. I was happy as a pig in poop untill I pulled the second one and saw that it was a plain 487. From what I understand the X head has a little larger runner volume. If this is true how well would they work together on a bomber stock? Somebody had obviously been using them that way for a while on the street.

iowatoolman
Dirt Freak

Total posts: 369
posted August 03, 2004 10:30 AM  
even with two years on the rods they are still gonna need to be reconditioned which is more money

as for tghe 487x heads yes that is true but nothing a little porting can't fix most guys i know look for 993 heads for porting them big (is a truck casting and is heavier so it don't crack)i have a set that are ported and flow almost as good as my darts 215cc

racer17j
Dirt Forum Champ
Total posts: 5390
posted August 04, 2004 09:44 PM  
sure if your building a scatter motor (claimer)
but i don't have a claim in my class so i put the goodies in mine

racer17j
Dirt Forum Champ
Total posts: 5390
posted August 05, 2004 05:08 PM  
Does anyone know the story behind GM PM rods. I have found a set for sale resonable. Any info is appreciated.

wenee9w
Dirt Roller

Total posts: 11
posted August 17, 2004 12:41 PM  
I hear when they break they break at the big end of the rod.I am a little leary myself of them but i have seen people run them.?

maniac motors
Dirt Maniac

Total posts: 128
posted September 09, 2004 04:16 PM  
go with the scat rods if you want reliability by the time you buy bolts and resize them you probably wont se much difference

racer s
Dirt Forum Racer

Total posts: 83
posted September 09, 2004 07:34 PM  
would you be ok with stock rods turning aroun 7000 rpm???????

iowatoolman
Dirt Freak

Total posts: 369
posted September 09, 2004 10:59 PM  
not even close to 7000 maybe 5000
i know guys that run stock rods to 6000 and that scares me

have you ever had a motor shell pieces out at you????

it is not a pretty sight

go with the scat or eagle sir rods

drive hard or drive home

powerglides
Dirt Freak

Total posts: 374
posted September 13, 2004 09:25 AM  
I have raced for 14 years and this year I got the best (most expensive) motor I have ever had from one of the most reputable builders in the area. I have always used recon stock rods for 1200-1800 laps up until this motor and NEVER had a problem. The new motor had Eagle stock replacement rods in it and it lasted 3 features before breaking a rod and destroying the whole motor. I am going back to garage built motors with stock rods. GM builds some tough stuff.

rfb320
Dirt Maniac

Total posts: 150
posted September 14, 2004 09:01 PM  
I have stock gm rods in my engine that I ran at 6500 all season and not a single problem. I did put arp rod bolts in and resized them and made them full floating. but they are still the stock rod

iowatoolman
Dirt Freak

Total posts: 369
posted September 14, 2004 09:28 PM  
tell everyone how much you spent getting ARP bolts installed then resizing and then getting them bushed for floating pins
???????????????
quote:
Originally posted by rfb320:
I have stock gm rods in my engine that I ran at 6500 all season and not a single problem. I did put arp rod bolts in and resized them and made them full floating. but they are still the stock rod


racer17j
Dirt Forum Champ
Total posts: 5390
posted September 14, 2004 10:22 PM  
PTM 84.99 GM Select Castings Used
Arp 190000 bolts
or go to www.gustafengines.com he has em for even cheaper
i've ran ema ll year in my b mod ask racer17j how my motor runs

Donnie Ross
Dirt Freak

Total posts: 264
posted September 16, 2004 04:54 AM  
do a search on rods and you will find hendrens and other pro motor builders prefer shotpeened and magnafluxed stock rods over cheap imports.

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