TimsLS1

Hi is a 5/16" cromoly 0.80" thick pushrod sufficient for my mild set up. Its a mild cam but my springs are not they are dual Pac springs, cam is 217/228 110 lsa .590 Valve lift. Don't imagine I'll ever Rev past 6500 more likely closer to 6000.

I wanted to use 11/32 but can't find them here in Australia in my 7.275" length. 5/16 thick 0.80 Wall is best I can do here.

Almost everywhere I've searched says use thicker pushrods if possible.

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Che70velle

iTrader: (6)

7.275 11/32 pushrods can be had from any pushrod vendor. Nobody in Australia has them? I know you guys pay a premium for import fees, but you can get them all day long, if ordering a set is feasible and you have the time.
What are the springs rated for, seat and over the nose?

TimsLS1

Thanks, Sorry correction I found one in Australia that has 7.275 11/32 but I don't trust them. The others and two large vedors in USA got back to me this morning and don't have them either. The springs are as follows.

• Install Load (LB): 160
• Install Height (in): 1.800
• Open Load (LB): 425
• Open Height (in): 1.125
• Coil Bind Max (in): 1.020
• Damper: No
• Rate: 392

Che70velle

iTrader: (6)

Call Manton Pushrods. They will build you a nice set. I ordered my last set from them, and had them in my shop in 5 days. Freaky fast turnaround, and they build pushrods for anything, from a 60 hp 4 cylinder to a 12k hp top fuel engine.

TimsLS1

Thanks,
Its very expensive with our Aussie dollar trading at 61 cents, I'll keep looking locally, would be nice to know if a an 0.80 wall 5/16 would be sufficient. But I'm guessing probably not from your reply.

Che70velle

iTrader: (6)

The 5/16 rods will work. But the 11/32 rods will do the job with much less flex. Anytime you can increase the diameter of your pushrods, it’s always a good thing.

RonSSNova

iTrader: (3)

You are approx 400lbs over the nose due to your lower lift.
Thats an avg number, many many setups using 5/16 .080” push rods.

11/32 certainly are a benefit on max effort high rpm big cam combos, but I don’t see them being necessary for what you are up to.

TimsLS1

Thanks I thought so, although I'm am using slow leak down lifters, I would have thought that they would not compress as easily as a standard lifter and might need a stiffer pushrod?
I wasn't sure if many people used the 5/16 0.80 with bigger cams largely due ignorance on the whole subject.

I found some pushrods for it locally in Australia $214 for 5/16 0.80 wall and $279 for 11/32 0.80 wall. This is the last thing I have to buy for my expensive basic rebuild, just didn't want to let the rest of set up down.

I was given a cheap vehicle by my mum as a gift yesterday so I no longer have to use my LS1 as my daily, could even go hotter cam now as fuel economy doesn't matter much anymore and don't have to use it for driving in slow traffic.

TimsLS1

You are correct I found this in link, the difference is too minimal for me to be concerned about.

https://ls1tech.com/forums/dynamomet...sure-diff.html

dreadpirateroberts

iTrader: (1)

i remember that dyno from years ago when i was worried about the same thing... with mild to moderate setups, the 5/16ths are definitely adequate for the job.