TRW Piston replacement - Speed Pro and the 'Z'

[Quickstop [UK]]

I have to find two equivalent pistons to make up the set in my truck - I have 4 x TRW L2441 .030 with D shaped cups and it looks like they are no longer made. Speed Pro now make them from what I can tell.

Speed Pro seem to have two equivalent pistons - the ZL2441F30 (Summit) and the L2441F30 (Jegs)

Both are D cups, both are 4.030, both are 5/64, 5/64, 3/16 rings and both are 1.560

Summit are $52.95 and Jegs are $66.

http://www.summitracing.com/parts/SLP-L2441F30/

http://www.jegs.com/i/Sealed-Power/844/L2441F30/10002/-1

Are they the same piston? The 'Z' in the Summit part has confused me. I think they ARE the same but is there any way to tell?

Thanks guys. Syclone 2612 WILL live to fight another day

 

[sytyguy]

Re: TRW Piston replacement - Speed Pro and the 'Z'

Same piston. Summit shows the manufacturer number, but Summit and Jegs both drop the Z for in house catalogging.

 

[wildphil]

Re: TRW Piston replacement - Speed Pro and the 'Z'

Probe makes a 2441 piston also. Others have used them.

 

[Quickstop [UK]]

Re: TRW Piston replacement - Speed Pro and the 'Z'

Got a link? Any suggestions of which one would be best? I'm looking at running with Summit...

 

[wildphil]

Re: TRW Piston replacement - Speed Pro and the 'Z'

At Summit it looks like they are sold in a set of 8. You could probably search and find individually sold pistons.
http://www.summitracing.com/parts/PBP-P2441F-030/

Here is a better price set.
http://www.flatlanderracing.com/probe-factorychevy.html

 

[fivetodrive]

Re: TRW Piston replacement - Speed Pro and the 'Z'

I have some good used ones... Not sure if you are looking for new...

But I can fit them in a medium flat rate box to the UK so shipping is easy to figure out.

Aaron

 

[Quickstop [UK]]

Re: TRW Piston replacement - Speed Pro and the 'Z'

The link I posted above is for a single piston. I can't see myself getting them for less than $55 so prob am set.

Good to know re: Probe though. I have never heard of them.

 

[Quickstop [UK]]

Re: TRW Piston replacement - Speed Pro and the 'Z'

Aaron - The other 4 going in are used so I am not being precious! I have to pay $120 ish for the 2 from Summit so if you can beat that and they're good, great!

Have you got some pics? Maybe PM me?

What rods are on there? The guy in the shop in the UK said you can't remove the rods so assuming you have stock rods with the stock crank grind then I am interested.

 

[fivetodrive]

Re: TRW Piston replacement - Speed Pro and the 'Z'

The rods are off the pistons you just press them on and off... But I have a lot stock rods as well. Hell let me look I might have a set on the rods... I was thinking of $20 each for the pistons plus shipping, if I have the ones on the rods maybe a bit extra for that. I will check the box.. Flat rate INTERNATIONAL medium shipping is kinda stupid at $47.95 but I could try to load the box up with other stuff as well, just have to keep under 20lb's for the international shipping...

What do you think?

 

[Quickstop [UK]]

Re: TRW Piston replacement - Speed Pro and the 'Z'

Aaron made an important point - are the stock rods tonawanda or Romulus? There was a number 5 stamped in the side on one of my pics.

Surely if the rods and pistons all weight the same, it doesn't matter too much? I plan to press out two rods from the vortec motor and reuse them with these two TRWs. The other 4 have the stock unknown rods.

Can anyone see any problems with this?

EDIT

RODS
There are four different rods in two different weights that come from two different engine plants, so there’s plenty of room for confusion, but it all works out if you follow these two rules:

Rule 1: Keep similar rods in sets by both appearance and weight;

Rule 2: Use only Romulus rods with Romulus cranks.

Then, the question is, how do you tell them apart so you can follow the rules? Start by sorting them by engine plant based on the shape of the balance pad on the big end. If the rod has a cast pad that’s only machined on the face, it’s a Tonawanda rod. These rods don’t have a forging number and may or may not have a dot on the shank. See photo.

If the weight pad on the big end is long and narrow and has been machined on all five surfaces including the sides, the ends and the face, it’s a Romulus rod. All of these rods will have an 818 or 045 forging number on the shank so they’re easy to identify.

After you have separated the rods by source, sort them by weight and put them in sets. The lighter ones will weigh around 662 grams, and the heavier ones should weigh about 675 grams.

The light and heavy rods can be interchanged in engines in sets, but it’s best to use the Romulus rods only on Romulus cranks because you may end up with a ticking noise if they are used with a Tonawanda crank. The Romulus rods have a wider face adjacent to the parting line that can hit on the side of the split pin rod journal, so the Romulus cranks are machined to provide additional clearance for the rods.

The Tonawanda cranks aren’t relieved in this area, so there can be light interference and a noise problem. The Tonawanda rods have the narrower face at the parting line so they can be used with either crank.

 

[proptop]

Re: TRW Piston replacement - Speed Pro and the 'Z'

New guy here and just my two cents. I would use your known good rods and get the older pistons from five to drive. The older ones (pistons) will be closer to the same weight that you have now. The newer ones are being made in India and are lighter. You should get it re-balanced either way but the older pistons are most likley the same weight.
Bob

 

[fivetodrive]

Re: TRW Piston replacement - Speed Pro and the 'Z'

Ok looked at the rods and they are marked k gm 045. So they are all romulus rods. Will try to upload pics from the phone.

 

[fivetodrive]

Re: TRW Piston replacement - Speed Pro and the 'Z'

Here are pics...