Question About 440 Piston Choices

[Rusty34]

Hey everyone,

I need some advice on piston selection for a 1971 440 Magnum rebuild. It's .030 now and needs to go .040 over. I really like the Speed-Pro L2295F because of the 1/16" top and 2nd rings and I can get around 10:1 with stock heads plus they weigh very close to stock pistons which makes them an easy install. I've not been able to find them anywhere in .040. It appears the L2295F or FA might have been discontinued and any 440 size seems to be getting very hard to find. Anyone know more about this?

Tnx in advance,
Rusty

 

[33 IMP]

Pretty sure the 2295s are done, though I was able to buy one (not a set) from summit a few years ago.
And, to the best of my knowledge, there was never any .040 over 2295, There MAY have been .060s, but I've never seen anything but .030.
I have several sets of Ross new in the box that I bought cheap several years ago (they are now double what I paid) but if I were buying now?.....
Icon, or RaceTek, and I'd plan on getting it rebalanced for much lighter modern pistons. (Those 2295s are HEAVY!).

 

[gtxrt]

Hey everyone,

I need some advice on piston selection for a 1971 440 Magnum rebuild. It's .030 now and needs to go .040 over. I really like the Speed-Pro L2295F because of the 1/16" top and 2nd rings and I can get around 10:1 with stock heads plus they weigh very close to stock pistons which makes them an easy install. I've not been able to find them anywhere in .040. It appears the L2295F or FA might have been discontinued and any 440 size seems to be getting very hard to find. Anyone know more about this?

Tnx in advance,
Rusty

why would you want a piston that weighs as much as stock when you can save about 150-200 grams per piston plus get any pin height you want and the exact compression.

 

[1968rt]

read this....says it all https://www.motortrend.com/how-to/mopp-0309-buyers-guide-to-choosing-the-best-piston-parts/

 

[steve340]

I agree - go lighter and just rebalance.
There are a few advantages to go to lighter pistons. For a street engine a cast piston is fine.
The KB brand seem to work fine and are available in many oversize's.

 

[Runcharger]

I agree: I used to run those heavy slugs and then try to rev it to the moon. The engines started to last after I got smart and started lightening them. These days just buy the lighter pistons.

 

[Geoff 2]

What I would be worried about if this is to be a street driver: is not the brand of piston but the fact that:
- there is no quench with factory heads
-.........10:1 CR
-........& pump fuel.

 

[lewtot184]

I use kb184's with open chamber iron heads. I think they're the only sensible choice for a pump gas open chamber head. I've never had any failure with them, beat the snot out of them. I do exactly what the literature says for installation. They are are lighter than stock and can be bought in .040 over.

 

[DanielSlocum]

I use kb184's with open chamber iron heads. I think they're the only sensible choice for a pump gas open chamber head. I've never had any failure with them, beat the snot out of them. I do exactly what the literature says for installation. They are are lighter than stock and can be bought in .040 over.

How tight did you run them?

 

[lewtot184]

How tight did you run them?

I like to run them close to the minimum, .0025". I am running a set at .0035" now. They can be somewhat noisey when cold because they have straight pins and drilled oil return ring grooves, but they seem to make the same power as 10:1 flat tops plus pump gas friendly. They're 100+ grams lighter than stock.

 

[What’s up dock]

The L2295's are domed, so you'll be over 10 to 1 without any milling or decking. And as said, very heavy.
The L2355's are a flat top, forged sick pack style piston and they are available in .040 over. In stock too. Heavy, but a good piston. 5/64th rings
Stay away from the L2266's, low compression forged. Heavy, and will be .100 below deck.
A good choice would be an SRP piston. Only 250 bucks or so more than the 2295's you mentioned. If you have a few extra bucks floating around, then jump up to a Diamond piston or something like that.
And yes, you want to rebalance the rotating assembly.

 

[33 IMP]

With a 90cc head, normal .039 head gasket, and an undecked block, my 2295s (supposed to be 11.5 to 1) came in at a measured 10.6 to one. (.040 deck height, if I remember right) With a blueprinted decked block, steel shim gasket, and an 83cc head, they might really be 11.5.
And I still don't think they were ever available in .040.

 

[threewood]

For a street motor without power adders, the KB 236 or 237 are good choices. I have the 237's in my 440, with Source heads are about 10.3:1. The 236 has a raised pad for open chamber heads.

Just looked at Summit, ICON forged are about the same price as the KB's. I'm not sure on weight difference.

 

[33 IMP]

For a street motor without power adders, the KB 236 or 237 are good choices. I have the 237's in my 440, with Source heads are about 10.3:1. The 236 has a raised pad for open chamber heads.

Just looked at Summit, ICON forged are about the same price as the KB's. I'm not sure on weight difference.

I would choose Icon forged 1000% of the time over KB's at the same price point.
If Icons were $200 more than KB's....... I'd still take the Icons.

But I was lucky enough to buy three sets of new Ross, for $300/ea, a few years back. Like jewels compared to trw's.

 

[threewood]

I would choose Icon forged 1000% of the time over KB's at the same price point.
At Icons $200 more than KB's....... I'd still take the Icons.

I'm happy with mine, but they were at least $300 cheaper than the ICONs in 2016. No difference now, so I agree. Forged are better. Both sets are about $600

 

[lewtot184]

I use kb in one of my engines, icon in the other. I match pistons to the combustion chamber and what my intent for the engine is. I ignore the hype.

 

[1968rt]

L2266 can be made to work. Closed chambered with shim gasket will get you to 9.5 without milling, but they are heavy (876g) I prefer SRPs basically JEs (690g)

Part# CH Weight PinWt CCs Deck Ht

L2266F 1.991 876 225 0 flat top .090

L2355F 2.061 872 225 -7cc .020

L2388F 1.926 819 225 0 flat top .155

L2295 2.029 817 250 13.1cc .140 dome .051

7025P 2.050 815 250 13.1cc .140 dome .051

 

[33 IMP]

L2266 can be made to work. Closed chambered with shim gasket will get you to 9.5 without milling, but they are heavy (876g) I prefer SRPs basically JEs (690g)

Part# CH Weight PinWt CCs Deck Ht

L2266F 1.991 876 225 0 flat top .090

L2355F 2.061 872 225 -7cc .020

L2388F 1.926 819 225 0 flat top .155

L2295 2.029 817 250 13.1cc .140 dome .051

7025P 2.050 815 250 13.1cc .140 dome .051

And ALL of those are well over 1000 grams, piston and pin, plus (mostly) 5/64 rings. The Grant domed ashtrays I took out of my max wedge were well over 1200 gr.
If I remember right, my stroker Ross are around 750 grams, with pins (bbc) and rings.

 

[RemCharger]

And ALL of those are well over 1000 grams, piston and pin, plus (mostly) 5/64 rings. The Grant domed ashtrays I took out of my max wedge were well over 1200 gr.

Gotta keep that a secret! If the S/S MW guys find out, they'll all quit racing and setting records!!!

(10.50s was the best I ever got out of a heavy slug 383 lol)

 

[33 IMP]

Gotta keep that a secret! If the S/S MW guys find out, they'll all quit racing and setting records!!!

(10.50s was the best I ever got out of a heavy slug 383 lol)

In my old trw catalog, the bbm pins were the heaviest in the book, and one version of the 440 piston was THE heaviest piston in the book! (NOT counting diesels).