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Author Topic:   ROD BOLTS
muddogg1
Dirt Roller

Total posts: 5
posted February 19, 2004 07:03 PM  
THERE IS A WAY TO INSTALL ROD BOLTS BY STRETCH INSTEAD OF TORQUE.I AM TRYING TO FIND OUT HOW TO DETERMINE WHAT STRETCH I NEED FOR A 351 WINDSOR AND A 289.CAN ANYONE HELP ME OUT?
THANKS.

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WALLACE M REID
19 BROADWAY DRIVE
GREENVILLE
SOUTH CAROLINA
29611

Ego Racing
Dirt Forum Champ
Total posts: 724
posted February 19, 2004 08:16 PM  
Yes. Speedway has a guage for measuring bolt stretch.

b4racing
Dirt Forum Champ
Total posts: 626
posted February 19, 2004 08:33 PM  
I would contact the place that manufactures the bolts to see what they suggest. Bobby

2nd2none
Dirt Forum Champ
Total posts: 755
posted February 20, 2004 05:30 PM  
you are heading in the right direction. Alot of rods get over torqed because "the books" say to torque them to 65 foot lbs. If you got a set of rods that have been on and off a motor a few times and the last time they get torqued to 65 ft lbs they may stretch .010 or more......thats way too much and you will have a rod bolt failure. If you call one of the high end rod manufactures like carrillo, crower, oliver etc. and ask them how much to torque their bolts they'd tell you the amount of torque doesn't matter you need to tighten that rod bolt untill it has about .005" to .008" of stretch, even if its only 40 lbs it'll still hold!!

2nd2none
Dirt Forum Champ
Total posts: 755
posted February 20, 2004 05:35 PM  
Also, you need to be able to check the stretch on final assy of engine. If you check it for stretch with the rod in a vice and it has .007" of stretch at 55 lbs when you pull it apart and put it in the motor for the final time and just go off the 55 ft lbs it now might have more than .007" of stretch. So be sure and check EVERY rod bolt for proper stretch on the final assy of the motor and dont worry about if 1 rod has 2 different torque settings for each bolt as long as that rods bolts have the same amount of stretch.

Ego Racing
Dirt Forum Champ
Total posts: 724
posted February 21, 2004 11:28 AM  
Correct 2nd. I have seen an engine for a mini stock where the guy torqued everything. I got there late and just started to check the engine over and found 2 bolts still loose to the touch, It was a problem on the bolt. If he were measuring streach he would have seen the problem, If I had been latter or not got there it would have went into the car.

muddogg1
Dirt Roller

Total posts: 5
posted February 23, 2004 07:55 PM  
I WANT TO THANK YOU GUYS FOR THE HELP.I BEEN OUT OF RACING FOR A LONG TIME AND A LOT HAS CHANGED.I AM A MECHANIC BUT I ALWAYS USE TORQUE SETTINGS,BUT I WAS READIND AN ARTICLE IN A DIRT TRACK MAG AND THOUGHT I MIGHT NEED TO TRY IT WITH STRETCH INSTEAD OF TORQUE.SOUNDS LIKE IT WILL WORK OUT BETTER.QUESTION NUMBER 2.ARE FORGED RODS BETTER THAN CAST RODS?SORRY TO ASK SO MANY QUESTIONS BUT IF ONE NEVER ASKS ONE NEVER LEARNS.THATS WHAT MY GRANDDAD ALWAYS SAID AND HE WASN'T WRONG TO OFTEN.THANKS GUYS.
MIKE REID.

2nd2none
Dirt Forum Champ
Total posts: 755
posted February 23, 2004 09:32 PM  
Yes, forged rods are better than cast, he!! anything forged is better than cast including cranks. 4340 forge is better than 5140 also.....

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