SOLD TRW 383 pistons .040

[Cranky]

Never installed L3057F pistons w/pins. NHRA approved legal replacements. Compression height is 1.900" 5/64ths ring groove. 200 plus shipping obo from 77505, Pasadena TX (Houston area)

 

[Cranky]

150 plus shipping.....

 

[okiemopar]

Pistons

What is the rated comp. on these? Thanks Ronnie

 

[Garys1969RR]

I think these pistons end up being about .032below deck. Then depending on chamber size, head gsk thickness, you can figure your compression ratio. For example, a 73 cc head volume, .020 gsk, a .040 O S 383 will be around 10 to 1 C/R. I'm not Cranky (today) but have been running some calculations on this lately. Thats my .02 cents worth. Good luck

 

[Garys1969RR]

Just did some quick checks, and an 80 cc head yields 9.6 to 1 C/R, and a 73 cc head is 10.4 to 1. With all other specs as above. I use the Keith Black C/R calculator.

 

[okiemopar]

Did you sell the pistons yet? Thanks Ronnie

 

[MoparMitch]

Can someone tell me how many cc's in 906 heads? Thanks

 

[Cranky]

Can someone tell me how many cc's in 906 heads? Thanks

Factory uncut open chamber heads run right around 90cc's.....

 

[Cranky]

Did you sell the pistons yet? Thanks Ronnie

I still have em....

 

[MoparMitch]

Thanks Cranky. I thought the 906 heads were closed chamber

 

[Cranky]

Thanks Cranky. I thought the 906 heads were closed chamber

Nope....915's were closed chamber and those were on 440's as a performance head in 67 only and those run right around 80cc. I understand you could find some 915's with the small exhaust valve on 383's but I've never seen any.

 

[kidmopar]

I have a set of 916 with the smaller valve coming here in a couple weeks from the machine shop. This is the closed chamber head cranky is talking about. they are 916 not 915, these were on a 383 i just picked up. these are actually easier for me to find then 915s. I have a set of those too and its a great head for increasing ur compression

 

[Cranky]

I have a set of 916 with the smaller valve coming here in a couple weeks from the machine shop. This is the closed chamber head cranky is talking about. they are 916 not 915, these were on a 383 i just picked up. these are actually easier for me to find then 915s. I have a set of those too and its a great head for increasing ur compression

Are you sure what you are talking about isn't a 516? Never heard of a 916 head for a BB. I have a pair of the 516's that I installed the larger 1.74 exhaust and cleaned up the valve pockets and did a mild port job to. They should work decently on a street engine. They are on a 440 with .020 steel shim gaskets with pistons that are .050 down and it works out to be 10.3-1 compression with a stock bore.

 

[Meep-Meep]

I actually saw a 66 383 with 915 heads from the factory. It was on some old big car back in the 80's that was donated to my auto shop and I tried to convince the teacher to give them up. He knew nothing about MoPar casting numbers but he knew they were closed chamber and that meant compression! Never did get them.

 

[okiemopar]

PM me on the pistons Thanks Ronnie

 

[kidmopar]

cranky, i checked back with the machine shop, u are right its 516 not 916 but theres a few sets out here ive seen, thanks, that number seemed funny to me too but i guess old age does strange stuff to ur eyes lol mine for sure!!

 

[Cranky]

PM me on the pistons Thanks Ronnie

PM sent....

 

[shag766]

cranky thats a fair price for new.

 

[Garys1969RR]

We bought a set of 915 heads that had the 1.60 ex valve in them. The guy has a bunch of old Mopar stuff, so no telling what they came off of. We had 1.75 ex valves installed and they work great on my sons 383.

 

[Meep-Meep]

We bought a set of 915 heads that had the 1.60 ex valve in them. The guy has a bunch of old Mopar stuff, so no telling what they came off of. We had 1.75 ex valves installed and they work great on my sons 383.

1.6 valve 915's are common. I have 6 sets of them and most are the small valve. Converting to 1.74 or even 1.81 is a non issue since the castings are the same.