ARP L19 7/16 Rod Bolts?

September 02, 2022, 02:37 PM

Mike Rietow

quote:
Originally posted by Big Steve:
L19 bolts in my MGP Aluminum rods call for .0065-.0085 with 50wt oil. One pull, no step torque

That's interesting. Is there a specific 50wt oil they suggest or send with the rods?

How is the torque wrench set to get to .0065? A lot of friction there with an aluminum rod - 50wt oil, my guess is 80, 85 ft pounds torque wrench setting.

September 02, 2022, 03:50 PM

Big Steve

105 ft lbs is the spec. std 50wt oil. most pull between .007-.008 at 105lbs. I have had some go past .009 those go in the trash. So far never had a bolt/rod failure so must be doing something right

September 02, 2022, 03:56 PM

Big Steve

3/8” head ARP L19 fastener: 65ft/lbs torque, 0.0045”-0.0055” fastener stretch
7/16” head ARP L19 fastener: 90ft/lbs torque, 0.0055”-0.0065” fastener stretch
1/2” head ARP L19 fastener: 105ft/lbs torque, 0.0065”-0.0085” fastener stretch

September 02, 2022, 03:57 PM

SCDIV1

79 ft lbs is what I see in some Steel rods...
About .007 stretch shown for Eagle steel rods with L19 bolts
No way I'd use specs from an aluminum rod in a steel rod UNLESS I could confirm the specs were the same...

I've had issues with rod bolts trying to get to a tq spec using oil and the rod manufacturer even said std 30 wt oil They would seize, grab and give a false tq. I mixed oil with anti seize paste and later down the road the same rod manufacturer put the same type anti seize paste in their rod boxes.....Crower steel with very high TQ spec bolts....

I snug the bolt and go right to the TQ spec and mostly use the ARP lube sometimes with a little oil mix....

I never used the L-19 bolts and the only rod bolt failure I can recall was one of those Crowers and it was due to that bad TQ issue with the bolt "seizing" before it got stretched properly....

When in doubt I spend time researching the issue and make a call to get the right info before guessing....

September 02, 2022, 04:08 PM

Mike Rietow

quote:
Originally posted by Big Steve:
105 ft lbs is the spec. std 50wt oil. most pull between .007-.008 at 105lbs. I have had some go past .009 those go in the trash. So far never had a bolt/rod failure so must be doing something right

I'd say so.

I'd also say the oil acts like thread locker when it's all said and done.

September 02, 2022, 04:25 PM

Mike Rietow

quote:
Originally posted by Big Steve:
3/8” head ARP L19 fastener: 65ft/lbs torque, 0.0045”-0.0055” fastener stretch
7/16” head ARP L19 fastener: 90ft/lbs torque, 0.0055”-0.0065” fastener stretch
1/2” head ARP L19 fastener: 105ft/lbs torque, 0.0065”-0.0085” fastener stretch

This is correct according to what I'm observing, ARP Ultra Torque assembly Lube.

September 02, 2022, 05:29 PM

TD3550

I preload mine twice in the rod vice. Normally i get 89Lbs @ 55-65 with the ARP lube. Yes i have a couple that after the second preload went into the dumpster. CYA. Very time consuming.

September 02, 2022, 07:53 PM

Big Steve

quote:
Originally posted by TD3550:
I preload mine twice in the rod vice. Normally i get 89Lbs @ 55-65 with the ARP lube. Yes i have a couple that after the second preload went into the dumpster. CYA. Very time consuming.

I do the same with the rod vice before installing the piston on the rod. If it comes up short I remove the bolt and re oil and pull again and generally they fall into spec.

Running a aluminum rod motor is expensive but the way I look at it cycling them out at specific amount of runs before they break is way cheaper than replacing them after one broke. I just put a new set in every season.

September 03, 2022, 10:07 AM

wideopen231

quote:
Originally posted by Big Steve:
quote:
Originally posted by TD3550:
I preload mine twice in the rod vice. Normally i get 89Lbs @ 55-65 with the ARP lube. Yes i have a couple that after the second preload went into the dumpster. CYA. Very time consuming.

I do the same with the rod vice before installing the piston on the rod. If it comes up short I remove the bolt and re oil and pull again and generally they fall into spec.

Running a aluminum rod motor is expensive but the way I look at it cycling them out at specific amount of runs before they break is way cheaper than replacing them after one broke. I just put a new set in every season.

Have had the its cheaper to replace rods than replace rods,block,pistons and possible cam and crank too many times. Never understood why some would want to push runs way too long. Had one guy run rods 60 runs and this was when most alky teams replaced rods 15 or 20 runs. Bolts were not as strong,was 20 plus years ago. Arp L79 bolts are the shyt.

Did have a crew member forget left loosy goosy righty tighty thing. Over tightened and stretched the hell out of bolt,hour glass shape good on woman not so much on rod bolt.LOL

September 04, 2022, 04:49 AM

Footloose

If the rods are in good shape it would not scare me to put them in a cheap budget bracket engine that sees only 6500 rpm. They can last a long time in a mild 500-600 HP. motor.

September 04, 2022, 01:10 PM

Toad1

I just finished the bottom end of a used 377". It had 7/16" L19. I called ARP and they said .0068 to .0075 stretch. At 78 ft lbs with my ol trusty torque they stretched almost exactly .007. They told me to use their assembly lube. These rods and bolts probably have 500 runs on them but in something making maybe 500-550 HP I did not feel $700 for rods and bolts were needed.

September 04, 2022, 02:00 PM

SCDIV1

Pretty much exactly what I posted days ago.....

September 04, 2022, 07:32 PM

Mike Rietow

quote:
Originally posted by SCDIV1:
Pretty much exactly what I posted days ago.....

I've got a set of instructions from Scat rods for a 496 BBC i'm doing, says if they stretch .0065 at 75ft lbs, throw them away no good.

September 04, 2022, 07:34 PM

Mike Rietow

quote:
Originally posted by Mike Rietow:
quote:
Originally posted by SCDIV1:
Pretty much exactly what I posted days ago.....

I've got a set of instructions from Scat rods for a 496 BBC i'm doing, says if you observe them stretch .0065 at 75ft lbs, throw them away no good.

Scat uses torque, that's just a check they include in the instructions to qualify each rod bolt I presume.