Moparts
Pistons for 360
Posted By: CoyoteJack
Pistons for 360 - 10/27/10 12:25 PM
I am in the planning stages of building a 5.9 magnum with a 6/71 on top. I was wondering if anybody else had built a 5.9 whether it be blown or turbo'd. If they have, what pistons did you use? I am trying to get down to 8 to 1 compression with Magnum heads.
Jack
Best bet are to run some custom pistons so you can move your rings lower and get any compression height you desire. I run JE.
Posted By: dodge turbo
Re: Pistons for 360 - 10/27/10 04:58 PM
Ross custom here...8:1 comp with a x-head..ceramic coated tops all for around $500
Posted By: CoyoteJack
Re: Pistons for 360 - 10/27/10 05:59 PM
Quote:
Ross custom here...8:1 comp with a x-head..ceramic coated tops all for around $500
That seems like a pretty good price.
Jack
WOW! $500 for a blower piston with coating? Did you get some sort of special deal?
Coating tops for a set of pistons is about $120 + pistons!
Posted By: dizuster
Re: Pistons for 360 - 10/27/10 11:32 PM
I was thinking the same thing. Probably more like $1000+ for something like that.
I can tell you to get to 8:1 on a 5.9 with iron heads is going to take a custom piston though.
I'm in the middle of doing a 360 with open chamber '308 heads, and I couldn't get the compression to 8:1 with an off the shelf piston.
The closest thing I could get was a Probe SRS series piston. 14.5cc dish, but even with that you'd need a crazy thick head gasket to get to 8:1
Posted By: CoyoteJack
Re: Pistons for 360 - 10/28/10 11:50 AM
Quote:
I was thinking the same thing. Probably more like $1000+ for something like that.
I can tell you to get to 8:1 on a 5.9 with iron heads is going to take a custom piston though.
I'm in the middle of doing a 360 with open chamber '308 heads, and I couldn't get the compression to 8:1 with an off the shelf piston.
The closest thing I could get was a Probe SRS series piston. 14.5cc dish, but even with that you'd need a crazy thick head gasket to get to 8:1
That's exactly what I am finding. A friend thought of going with a chevy piston and getting my rods bushed to the chevy pin size, but up here the machinist's want a small fortune.
Jack
My custom JE pistons were $950, + rings. Since custom, I put the ring pack low, 9.3:1 compression with my heads, .927 pin. I bought 6.200 rods with 2.200 journals.
Posted By: dvw
Re: Pistons for 360 - 10/28/10 02:03 PM
I have a 340. 7.9-1 with a 6.25 rod. Venolia pistons were $500 in 1991.
Doug
Posted By: dizuster
Re: Pistons for 360 - 10/29/10 05:32 PM
Depending on the cam, the chevy pistons might not work anyway. Valves are in a different location/different angle...
How much boost are you going to try to run with this thing?
I mean you can always get a .120" thick cometic gasket, but they are expensive...
Posted By: todd440
Re: Pistons for 360 - 10/30/10 12:23 PM
Depending on what you want, I can have custom Diamond pistons made. If you go to a full dish design, then up to a 50cc dish is not a problem. I can even do a group buy if I get at least 5 sets of the same piston.
Posted By: CoyoteJack
Re: Pistons for 360 - 10/31/10 01:25 AM
I am only looking at running 8 lbs of boost. But you know how that goes. If 8 lbs is good then 10 must be better, and so on. LOL
Jack
Posted By: CoyoteJack
Re: Pistons for 360 - 10/31/10 01:27 AM
Quote:
Depending on what you want, I can have custom Diamond pistons made. If you go to a full dish design, then up to a 50cc dish is not a problem. I can even do a group buy if I get at least 5 sets of the same piston.
What kind of money are you talking about. By the way I won't be building this until the spring. Just trying to get my head around what is required first.
Jack
Posted By: dizuster
Re: Pistons for 360 - 11/01/10 12:56 AM
Are you trying to run this thing on pump gas? Even so, I wouldn't be afraid to run 8~10psi with a 6-71 at 8.5:1. You could get there with the Probe's that I mentioned above. The top ring is .320" down from the crown as I remember. So not a bad choice for a blower piston...
With a splash of race gas, you could run even more if you wanted to "turn it up".
Posted By: CoyoteJack
Re: Pistons for 360 - 11/01/10 12:36 PM
Quote:
Are you trying to run this thing on pump gas? Even so, I wouldn't be afraid to run 8~10psi with a 6-71 at 8.5:1. You could get there with the Probe's that I mentioned above. The top ring is .320" down from the crown as I remember. So not a bad choice for a blower piston...
With a splash of race gas, you could run even more if you wanted to "turn it up".
Yes on the pump gas. This is going to be a street engine to replace my current LA/Magnum hybrid. A great working engine but I want the eye candy sticking out of the hood. Not to mention the extra thrills of close to 600 HP and TQ. Do you have a part number for that probe piston? I would like to check it out.
Jack
Posted By: dizuster
Re: Pistons for 360 - 11/01/10 07:39 PM
Sure, no problem...
http://www.probeindustries.com/Chrysler_360_14_5cc_Reverse_Dome_SRS_Pistons_p/12351.htmI got them from
www.cnc-motorsports.comThey were BY FAR the best price. Just call them and tell them what you want to order, it's not on their website.
Posted By: CoyoteJack
Re: Pistons for 360 - 11/01/10 07:55 PM
Quote:
Sure, no problem...
http://www.probeindustries.com/Chrysler_360_14_5cc_Reverse_Dome_SRS_Pistons_p/12351.htm
I got them from www.cnc-motorsports.com
They were BY FAR the best price. Just call them and tell them what you want to order, it's not on their website.
They must have added them to the website since you bought them. Strange that the compression ratio is a little different from Probes site. I would still have to use a thick gasket to get down to the compression ratio I want, but I can live with that.
Thanks
Jack
Posted By: dodge turbo
Re: Pistons for 360 - 11/01/10 08:17 PM
like i said call Ross they will make you a custom piston for the same price as a shelf piece
Posted By: dizuster
Re: Pistons for 360 - 11/02/10 12:14 AM
I'm sorry man... but you can't get a Ross custom made for $499 shipped with pins...
The off the shelf Ross flat top is $100 more then that, and they don't even offer a dished shelf piston from what I see...
How can they be cheaper then that?
BTW... not to hi-jack but Dodge Turbo your truck is awesome... check your PM...
Posted By: todd440
Re: Pistons for 360 - 11/02/10 12:24 AM
I'm still waiting to hear back from my Diamond rep for pricing. The way I figure it, at 62cc head, 9.0 cc gasket, ect, you would need a 30cc dish to get you to 8.4 to 1. That's based off of .030 over on a 360, stock stroke.
Posted By: dizuster
Re: Pistons for 360 - 11/02/10 12:32 AM
Todd you're right my mistake. I had planned on running thick gaskets all along on the motor I'm building now (so that was stuck in my head). You're right you can't get there with a stock thickness gasket. It takes an .090" gasket or so to get there on the Probes.