L2355F TRW Pistons- Good Choice?

I'm putting together a 78 block, 79 build date, 440 RV motor. Going into a 2wd Ramcharger.

I'm looking to bring the compression up and have a nice respectable cruiser/driver thats got a bit to play with once in awhile.

I found a set of new in the box TRW L2355f pistons. But it seems they are discontinued so specs on them are not easy to find.

They were originally purchased for the guys 70 440 6 pack superbee. But he went with a high compression piston instead.

These have been on a shelf for 20 or more years.

You must not have looked very hard. You can by them anywhere. Summit has them for $370.

https://www.ebay.com/i/253864478565...Hj4zm6wIViuCzCh3XQACREAQYASABEgKIL_D_BwE

Strong
Tall compression distance
Heavy

Comp height= 2.061"

Weight= 872 grams (.030" over)

Valve cuts = 7 cc's

Yep, about 1 lb heavier each than a modern piston. We used to build them with these slugs and the bobweight was around 3200 or 3300 grams. Now the bobweight is down in the 2500 gram range for a lot of BB engines that I see.

Are you sure?
1 lb. is 454 grams

Not TRW, different brand yes. Wasn't sure if the specs would be the same under a different manufacturer.

These are SpeedPro not TRW.

My concern was that a different manufacturer may have made some changes from the TRW specs.

Federal-Mogul absorbed TRW probably about 25 years ago.

Some non brand-name parts are listed with TRW numbers to make identification easier.

Thank you for this information. I haven't delt with any performance engine building since the late 90's

I'm just trying to get up to speed again. I'm sure I have forgotten a lot, and there's probably a slew of new stuff, or a new different way of doing it that I don't know.

I've had those pistons in my 440 for 15 years or so. Edelbrock RPM heads and a Racer Brown SSH-44. No complaints here.

Looks like the Federal-Mogul/TRW thing happened in 1992.

Then they acquired Sealed Power/Speed-Pro in 1993.

I remember when TRW started their name in the early 1960s, I think it stood for Thompson Racing Wholesale
One of the local parts stores started pushing the TRW line back then

Thompson Ramo Wooldridge.

Any custom piston manufacturer make something SIMILAR to the 2355 as a lite weight?

If you are doing a complete engine, there are much better pistons out there these days. Unless this guy is practically giving them away, I'd look around a little more.

I have KB pistons in a 360, I used them because I got them for free. A friend had them sitting on his shelf for 10 plus years.

Yes almost all of them have a shelf stock piston that is close to that one only way lighter. I used a set of ross with manley h-beam rods and had a bobweight in the 2400s.

Same CD ? ... flycuts for what cam ? How does the price and weight compare to the heavy ones ? Pin size ?

More money of course, like $600-700 a set
1.09 or .990 pin
Lighter, go to the ross site and look, there are even lighter, shorter skirt piston brands available.
They are flycut, 4cc if I recall, cleared my .590 with 2.14 1.81
Cd is close, 2.065 they end up about .017 in the hole in an unmilled block

I think Speed-Pro sells a lightweight version of the 2355.

These have a date of 1980 on the paperwork that comes with them.

And as far as cost, they are quite attractive at $100 for the set. And that includes a never mounted Holley Street Dominator intake to boot.

This is a shoestring budget build, using parts I have gathered over the last couple decades.

I understand they may not be the newest technology but at the price I feel like I can live with the extra weight. I'm not building a full on race motor.

https://www.campbellenterprises.com/mopar_ross_pistons.htm
The Ross shelf equivilant is 647 grams

https://www.manciniracing.com/keblicfhrsep.html
The KB Icon piston is 692

I didn't find any lighter weight Speed Pro/Sealed Power stuff

Are you putting new rods in to this engine? Any aftermarket rod I've seen are for a floating pin, the TRW/Sealed Power pistons are a pressed pin.

I plan to use the existing rods. If they all check out. There's a chance they may be "six pack" rods, it seems they were often used in tge truck engines from information I recall.

Again probably not ideal due to weight (or so I've been told) But they lasted this long.

Kind of a no brainer then.

I've run the similar boat anchor (my engine builder calls them) L2293 pistons in 3 different 383's and they have always been outstanding.

Yes they are heavier than the new stuff. I've dropped valves, broken camshafts, rockers, pushrods, bent valves but the pistons live on.

I'd estimate I've put thousands of runs on them over the years.

I damaged one when a valve dropped but we swapped it with an ebay spare and were racing again the next weekend. I also pinched a ring during assembly once.

They can be noisy on cold start-up (piston slap I guess) but they are the only dome piston available for a 383 that I'm aware of.

Maybe someday I'll get a set of custom $$$ pistons made to compare. My theory is the lighter assembly free revs faster but the gains would be negligible on the track but who knows.

I had the same pistons in my 383 years ago. And yes they were a bit noisy on first start. But they served me well as well. I assumed it would be the same with these.

Probably the best piston you could use would be the KB hyperutectic. They don't expand like other pistons allowing tighter clearances. Much lighter and stronger than regular cast pistons. Manufactured by United Engine and Machine. If you have six pack rods, don't use them. They are very heavy and no stronger that the LY rod which is a common 4 brl rod.

Those type rods will hurt the upper RPM limits of the motor by around 300 RPM
Almost as bad as using the stock street hemi rods in a 440

I agree with Dwayne, id take the deal. Ran them in stock car motors for years at a constant 6000 to 6500 rpm, never had a problem with stock rods. Jim.

For that price I would use them but no 6bbl rods. LY rods, new rod bolts, resize, and balance it. A rev limiter would be smart. Heavy pistons and high rpm, on either of those rods will stretch them, and raise the compression, so you do get a warning, then they break at the beam. It is wise to know your compression, then check it after a hard missed shift or driveline failure, if it raises 5 lbs change the rods, as you have a time bomb on your hands. Great piston other than that.

Is that piston number for the 6 pack motors or the higher compression ratio race pistons?

2355 is 6bbl