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-   -   Upgrading Rod bolts on stock bottom-end - post if you've done it (https://www.evolutionm.net/forums/evo-engine-turbo-drivetrain/458097-upgrading-rod-bolts-stock-bottom-end-post-if-youve-done.html)

scheides Nov 11, 2009 09:18 PM

Upgrading Rod bolts on stock bottom-end - post if you've done it
 
Let's talk making 'big' power on the stock bottom-end reliably.

I keep going back and forth on doing this, and have for about two years. Where my car is currently at, I've heard of spun rod bearings, but at the same time there's lots of other people w/ good luck on stock bolts. If I want to push the stock bottom-end further, it would prolly be wise to do it, but I'm wondering what all the other locals are doing.

If you have actually done this, or know someone that has, please comment:

-Have you done it? Drop oil pan, swap bolts, torque, done, or is there more to it?
-Once they are in, how much further is the bottom-end safe to push?
-How reliable is this, long term?

Evoluvin Nov 12, 2009 02:03 AM

Also wondering this but I think you would be better off getting pistons and rods.

kanyonkid Nov 12, 2009 02:10 AM

i havnt done this yet, but once i get back to the states i am gonna do it since i've had my rod bolts for almost a year now jus sittin in the closet... i am only doing it because i have NO plans any time soon to upgrade my block as i will not be pushing over 420whp, but it's an easy straight forward install (if u know a decent amount about mechanics). Same thing as to why some people do head studs and some do not... just another one of those "cheap insurance" things....

03whitegsr Nov 12, 2009 10:58 AM

I've done it. When pulling out my stock bolts, I found some torqued as low as 16 ft-lbs where the tight ones were up around 34 ft-lbs.

Obviosuly they weren't installed lose and the bolts had stretched that much. This is just a 300HP stock redline '03 with 50k miles.

binky Nov 12, 2009 11:15 AM


Originally Posted by 03whitegsr (Post 7708553)
I've done it. When pulling out my stock bolts, I found some torqued as low as 16 ft-lbs where the tight ones were up around 34 ft-lbs.

Obviosuly they weren't installed lose and the bolts had stretched that much. This is just a 300HP stock redline '03 with 50k miles.

Wonder if I should do this to my motor....



-Bink

Chele Nov 12, 2009 11:29 AM

I had it done. A month or so later one of my bearings decide to go for a spin. Coincidence? I'm not sure.

scheides Nov 12, 2009 11:48 AM


Originally Posted by 03whitegsr (Post 7708553)
I've done it. When pulling out my stock bolts, I found some torqued as low as 16 ft-lbs where the tight ones were up around 34 ft-lbs.

Obviosuly they weren't installed lose and the bolts had stretched that much. This is just a 300HP stock redline '03 with 50k miles.

Did you torque all the new bolts to spec then? Any issues since?


Thanks for the feedback everyone, keep it coming!

scheides Nov 12, 2009 11:49 AM


Originally Posted by Chele (Post 7708651)
I had it done. A month or so later one of my bearings decide to go for a spin. Coincidence? I'm not sure.

Any comments on the procedure that was used? How much power were you making at the time?

l2r99gst Nov 12, 2009 12:00 PM

You should never use torque specs for rod bolts. You should use a stretch gauge.

For something that important, a torque number isn't going to tell you much. A stretch gauge tells you exactly when you are at the fastener's designed amount of preload.


Eric

scheides Nov 12, 2009 12:02 PM

Can you elaborate on how specifically you use the stretch gauge? Ever done it on....stock rods while they were still in the car? :)

apagan01 Nov 12, 2009 12:06 PM


Originally Posted by l2r99gst (Post 7708723)
You should never use torque specs for rod bolts. You should use a stretch gauge.

For something that important, a torque number isn't going to tell you much. A stretch gauge tells you exactly when you are at the fastener's designed amount of preload.


Eric

well said

l2r99gst Nov 12, 2009 12:09 PM

Here's an article I found just searching google for 'rod bolt stretch gauge'.

Murf Nov 12, 2009 12:17 PM

A friend of mine swaped his rod bolts out with arp's. He removed the pan and did one rod at a time, and one bolt at a time. You can pm him and ask him about it..Go into the Reno thread in the west coast forum...his screen name is Jer.K

Trojan man Nov 12, 2009 12:17 PM

Had mine done 2 years and 20k miles ago. Never a problem since, stock block 30r @31psi on meth daily. Revving to 8k (not daily but close) and even 9k a few times when the shifter locked me out at the track . As was said, use a stretch guage and if done correctly you shouldn't have issues.

scheides Nov 12, 2009 12:21 PM


Originally Posted by Murf (Post 7708786)
A friend of mine swaped his rod bolts out with arp's. He removed the pan and did one rod at a time, and one bolt at a time. You can pm him and ask him about it..Go into the Reno thread in the west coast forum...his screen name is Jer.K

I looked in that thread, searched for his username and 'rod' and 'bolt' and 'bolts' with no luck. Can you link to it?


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