1937 3620 Pistons

[rcull]

Just called Egge for some piston pricing, ouch!!! Does anyone have any alternate sources for some oversize pistons for a 1937 3620?

[Matt Harwood]

Egge makes most of the aftermarket pistons out there, so you're not likely to find cheaper slugs unless you maybe find some NORS pistons on eBay (although they're neither guaranteed to be cheaper than Egge nor are you assured that they will fit properly). JE, Wiseco, and others make custom pistons, but if Egge surprised you, they'll give you a stroke. 

 

I'd bite the bullet and buy proper new pistons from a reputable source like Egge rather than rolling the dice to save a few bucks (and you will only save a few bucks no matter what alternatives you find). Why take a chance with something so vital to the success of the rebuild? Nobody ever regrets doing it right the first time. 

[trimacar]

I'd look at Arias if I were you, I know we can't criticize too much on this forum, but the scrambled name isn't the best now.  If you spend just a bit more on Arias quality, you won't be disappointed.  You might be when your hen's lay break in the carton, or worse, in the jugs......

 

https://ariaspistons.com/

[rcull]

Egges price was about $1200.00, so I expect I can go just about anywhere for a competitive price:(

I would not have expected more than maybe half that.

 

 

Edited July 31, 2018 by rcull (see edit history)

[Bloo]

Arias, Ross, Wiseco, JE, etc. Yes, it is expensive.

 

Piston technology has changed a lot in the last 30 years or so. Custom pistons may give you the opportunity, if you choose, to have less weight (easier on the bearings), modern rings (smaller. last longer, control oil better, and wear the cylinder less), full floating pins (if the engine has some goofy pin arrangement that makes you nervous), possibly raise compression slightly (and tighten up the quench zone on some engines).

 

If the block needs boring, get the modern pistons. This is a place where it makes sense to spend the money.

 

 

[trimacar]

11 hours ago, Matt Harwood said:

a reputable source like Egge

Matt, I agree with almost everything you post!  Not this, though, the quality isn't there anymore for this company, sad to say.....

[Bud Tierney]

(1) Bloo---how far afield can you go on weight (lighter pistons, easier on bearings) without considering balance problems??

(2) rcull---if you've looked for NOS/NORS pistons, are you aware your pistons came in models up to 1940 and possibly later (1940 catalog listing)?

That catalog shows a piston change in 1937----"oldstyle engines" 1934-36,  change 1937 for 37-40 engines...

[Bloo]

1 hour ago, Bud Tierney said:

(1) Bloo---how far afield can you go on weight (lighter pistons, easier on bearings) without considering balance problems??

 

 

Is this an Ambassador six?

 

Inline sixes are inherently in primary balance, and the crank is balanced only to itself. The pistons are simply matched to each other for weight, so you can go as light as you want on the pistons without rebalancing the crank. 

 

If it is an eight, the crank (and rods) would need to be rebalanced for lighter pistons. Of course a custom piston supplier could probably do original weight if that is what you wanted.

 

If it were me, I would probably get it balanced anyway. There is really no downside. IIRC Nash was an early adopter of electronic engine balancing. I am not sure if they were doing that yet in 1937, but they may have been. They certainly were in the early postwar era. I had a 1951 Statesman that you could not hear idling, even standing next to it with the hood open.

 

[rcull]

7 hours ago, Bud Tierney said:

(1) Bloo---how far afield can you go on weight (lighter pistons, easier on bearings) without considering balance problems??

(2) rcull---if you've looked for NOS/NORS pistons, are you aware your pistons came in models up to 1940 and possibly later (1940 catalog listing)?

That catalog shows a piston change in 1937----"oldstyle engines" 1934-36,  change 1937 for 37-40 engines...

I don't know if these are the newer or older style pistons without some specification to compare.

It is a six cylinder and balance will be checked before assembly.

 

We may have access to a NOS set of flathead pistons which are 2-1/4" bore instead of 2-3/8". That would require sleeving all 6 cylinders! Not first choice, but the piston price is right making it an option. The pistons in the motor have about .002" wear and the ring clearance is about .003"-.0035". So loosing a little volume for NOS pistons may be better than sleeving for pistons with wider than desirable ring land clearance.