Page 1 of 1
forged pistons for 291
Posted: Thu Dec 14, 2006 10:33 pm
by Gullwing
At $800 forged Ross pistons are a little pricey. Has anyone tried using pistons from another make motor that are about 40% cheaper. The 265 Chevy motor had about the same bore as did an AMC motor. Anyone ever tried that. Oh yeah I am shooting for a flat top 8:1 compression ration.
Posted: Fri Dec 15, 2006 7:13 am
by 392heminut
I think where you will run into problems is with the valve relief cuts in the piston tops. Chevys are wedge heads, the valve reliefs are nowhere near where they would need to be for a hemi head.
Posted: Fri Dec 15, 2006 10:50 am
by desotoman
I know of one guy that did it. He was a machinist by trade and took a set of 265 chevy pistons and put them in his 291 desoto. It has been a long time since I have talked to him but as I recall he used some kind of ford rod also. This was many many years ago when 265 pistons were dirt cheap.
Question? Is this a race motor? Do you really need Forged pistons? Cast piston will work fine for the street. Just a suggestion.
Good luck on what ever you decide.
Posted: Fri Dec 15, 2006 11:43 am
by johnny5
Have you tried Venolia? They're better quality and probably a couple hundred buck less than Ross.
Posted: Sun Dec 17, 2006 2:00 am
by 41hemi
I used Silvolite pistons made for the 292 Ford Y block in my 330 Desoto which I think has the same bore as the 291. The stock bore 292 piston was actually .030 over for my 330. All that was needed was to cut the reliefs in the pistons.
Posted: Sun Dec 17, 2006 8:47 am
by TrWaters
I have a set of NOS L2091F TRW .030 forged pistons sitting on the shelve for this very reason.
These are for a HD truck application, and are a higher compression than the car pistons.
They have a thick top, and cutting a bevel on the outside edge and valve notches are no problem.
When you have the rods refurbished, just bush to the correct pin size.
Keep in mind, that unless you can do some of these operations yourself, you probably wont save much money in the end over buying pistons.
Posted: Thu Apr 05, 2007 1:57 pm
by desotohemibill
I recently sold a 291 and a 341 to 2 different buddies. Each of them bought Venolia forgings at 9-1. They ran about $525.00 a set. The 291s have quite a dome. I will send a photo of them on request.
Cheap 291 pistons
Posted: Wed Jan 16, 2008 1:23 pm
by jimstandefer
I'm using chevy 305 flat top (no valve notches) hypereutectic Keith Black pistons avail. on ebay for $189. Using chevy stroker 6.125 rods. ($125.) 330 crank destroked to 3.7" with mains turned for 291 and rod journals for 350 chevy. ($450.) Works out to 0.0" deck. and about 8.0 to 8.5 cr. Heads could be milled to increase cr. but I'm going with a blower so need for more cr. Making intake - Desoto flanges avail for $55. (and exhaust flanges same price). Main body of intake (box) is piece of U shaped thin structural steel used in pre-fab metal buildings. Using 1.94 valves from 330 and pontiac exhaust valves in the 291 heads. Still, trying to watch the pennies it is still VERY expensive.
Re: Cheap 291 pistons
Posted: Thu Apr 03, 2008 12:43 pm
by jimstandefer
jimstandefer wrote:I'm using chevy 305 flat top (no valve notches) hypereutectic Keith Black pistons avail. on ebay for $189. Using chevy stroker 6.125 rods. ($125.) 330 crank destroked to 3.7" with mains turned for 291 and rod journals for 350 chevy. ($450.) Works out to 0.0" deck. and about 8.0 to 8.5 cr. Heads could be milled to increase cr. but I'm going with a blower so no need for more cr. Making intake - Desoto flanges avail for $55. (and exhaust flanges same price). Main body of intake (box) is piece of U shaped thin structural steel used in pre-fab metal buildings. Using 330 valves valves in the 291 heads (large exh. valve better for blower). Still, trying to watch the pennies it is still VERY expensive.
Re: Cheap 291 pistons
Posted: Thu Apr 03, 2008 12:53 pm
by jimstandefer
jimstandefer wrote:jimstandefer wrote:I'm using chevy 305 flat top (no valve notches) hypereutectic Keith Black pistons avail. on ebay for $189. Using chevy stroker 6.125 rods. ($125.) 330 crank destroked to 3.7" with mains turned for 291 and rod journals for 350 chevy. ($450.) Crank counterweights must be turned down .300" in lathe to clear bottom of cylinders. Works out to 0.0" deck. and about 8.0 to 8.5 cr. Heads could be milled to increase cr. for normaly aspirated but I'm going with a blower so no need for more cr. Using 330 valves in the 291 heads (large exh. valve better for blower). Using blower intake fabricated by Jack Wagner in Lawton, Ok. (beautiful intake !!) Still, trying to watch the pennies it is still VERY expensive.