New pistons 73g heavier

[Knight rider]

the stroker kit I used was a procomp one

Good thing you didn't buy an expensive stroker kit. Can you imagine how much it would have cost to get top-quality parts reworked?

I actually don't pay for any machine work as my old boy has a engine recond shop unless it's a small job I use someone closer and all the work I'm doing now is because I wanted too, the engine was going fine I just decided to have a play porting the heads than thought I should freshen up the bottom end, which lead to the piston change which has made things a bit of a challenge but I'm glad I did cheers

Any ideas on the rods ? I like the idea of running Cleveland bearings but if it's not really any better it's alot easier to just get Windsor bearings and move on

[Mark O'Neal]

I'm going to be ordering these trend pins at 88g that's a saving of 42g so I'll be only 31g underbalanced so I'm sure that will be fine, unless for some reason this pin isn't a good idea in a street car ? Also I couldn't see the specs on the trend website but the seller confirmed the weight at 88g cheers and thanks again

https://www.ebay.com.au/itm/Trend-H927- ... 1716871705

When you call Trend talk to them about you application. I wouldn't go below 150 wall with your application... but that's just me.

Good luck with your build!

No, it's not just you.

It's anyone with a lick of sense.

[Knight rider]

I'm going to be ordering these trend pins at 88g that's a saving of 42g so I'll be only 31g underbalanced so I'm sure that will be fine, unless for some reason this pin isn't a good idea in a street car ? Also I couldn't see the specs on the trend website but the seller confirmed the weight at 88g cheers and thanks again

https://www.ebay.com.au/itm/Trend-H927- ... 1716871705

When you call Trend talk to them about you application. I wouldn't go below 150 wall with your application... but that's just me.

Good luck with your build!

No, it's not just you.

It's anyone with a lick of sense.

I think you're saying the h-13 .095 wall pins are no good ? If so please tell what they would suit I'm yet to see a lighter pistons that takes a 2.750 long pin so what would these pins even suit, trend site says there rated to 700hp NA ? Cheers

[Mark O'Neal]

When you call Trend talk to them about you application. I wouldn't go below 150 wall with your application... but that's just me.

Good luck with your build!

No, it's not just you.

It's anyone with a lick of sense.

I think you're saying the h-13 .095 wall pins are no good ? If so please tell what they would suit I'm yet to see a lighter pistons that takes a 2.750 long pin so what would these pins even suit, trend site says there rated to 700hp NA ? Cheers

No good? I did not say that. Pins are selected in accordance with the intended usage. H/P has nothing to do with it. Cylinder pressure, RPM, piston weight (the heavier the piston, the heavier the pin) and tune are all that matter.

Since this is not a 2bbl, flattop oval track motor, nor a Super Stock car, then the part is the wrong part for the job. You will soon find a situation where the pin will begin oscillating and it will tear the bottom out of your pistons.

Never mind that the H-13 pins probably cost you more than it would to BALANCE THE MOTOR AND DO IT RIGHT. But I'm sure you'll solve that problem when this one blows up.

[Knight rider]

Ok you've sparked my interest again in this even though I've made that decision to use them but it still isn't together

First thing the pins where less than halve the cost of balancing using Malley but that's not important.

What's is and these are just question you either know or you don't, I don't that's why I'm asking

The pins that came with the pistons are 5115 Low carbon steel 150" wall the question is what wall thickness is equivalent in strength using H-13 pins ?

Also have you seen these pins used in similar app and it failed as you say it will ?

Really just looking if this is a real problem or is the easy answer it won't work. Cheers

[Mark O'Neal]

Ok you've sparked my interest again in this even though I've made that decision to use them but it still isn't together

First thing the pins where less than halve the cost of balancing using Malley but that's not important.

What's is and these are just question you either know or you don't, I don't that's why I'm asking

The pins that came with the pistons are 5115 Low carbon steel 150" wall the question is what wall thickness is equivalent in strength using H-13 pins ?

Also have you seen these pins used in similar app and it failed as you say it will ?

Really just looking if this is a real problem or is the easy answer it won't work. Cheers

I've been at this, making pistons for forty years.

150 wall carbon steel pins are stiff. H-13, ..095 wall pins are flexible.

Have at it.

[MadBill]

For the record, all steels have the same stiffness*, which is what matters most for a wrist pin. (*Modulus of elasticity or Young's modulus, ~ 29,000,000 psi.)

[Mark O'Neal]

For the record a 150 wall pin is stiffer than a .090 wall pin. And a 2.500 length pin is stiffer than a 2.750 pin.

They should run .090 wall H13 pins in Top Fuel. Seems like a great weight saver.

[Knight rider]

Thanks for all info, I guess the only thing that I haven't really understood is the pins that came with the pistons are 5115 low carbon .150" pins which there would be no question about running them. I guess I thought the point of H-13 pins was so you could run thinner lighter pins with the strength, much like running tool steel retainers. Cheers

[MadBill]

Typically pin issues are due to flex, not breakage or wear, so the greater strength (UTS) of the H13 pin is less important than its greater flex due to the 0.095" vs. 0.150" wall.