well I cannot find pistons that are very affordable for the292. Just a thought but I have a nice lathe and was wondering if the is any other( more affordable) piston I can purchase and maybe perform a cr reduction to it? just take some material off the top and have a nice set of flat tops. Well I am new to cars and 6s but I am willing to throw time at it in leiu of mony. any thoughts or sugestios on getting a 292 close to 10.5:1? granted 0 deck and how much off the head.
How far down in the hole are the OEM pistons? The 2.009" compression height is pretty much an antique. I don't know of any direct interchange in the 3.875" bore range. If you're doing a complete rebuild with a reground crankshaft, it's basically free to have the crankshaft slightly offset ground to raise the piston in the hole. A set of .030" under rod bearings costs the same as any other and can raise the piston .015" for more compression. You have already considered milling the head and block also to get zero deck/smaller combustion chamber? jack vines
That is the problem with doing the 292. The 250 is super easy with early 307 pistons being perfect (later 307s have so much chamfer on the side of the crown that it hurts compression so ones only for or from the late 60s should be used. ) Also sometimes we avoid custom made when they are really not that expensive. A set of 8 last time I had some made to my specs was about $634 so six would be about $475 then. $475 to get EXACTLY what you want is not bad even for someone as cheap as I am. I have used Ross for most of my custom orders. Forged light weight and exactly as ordered them is hard to beat. Might be $600 today. Last ones I had made were 2006 I think. However, Like you I also enjoy reworking others . In the slant six world one trick is to use longer rods (198 rods in a 225) to bring the piston up the hole. I dont know but perhaps a Buick or Olds rod of a longer length would work for you too. I have been down this exact road with customers and I always steered them to the 250 where a Killer six can easily be built for very little gold. (IE Four America 35 Chev Vintage stock car was one I was involved it. It sure doesnt lack for power and it is a 250.) However if your heart is set on a 292 and it is carved in stone I can appreciate that as well. Don
yes already commited. Now I see after the purchase the added expense with this motor. Pistons are 600-700$$$$. not a poor mans build. unfortunatly I am a poor man monetarily.i was just hopeing I could pick up cheaper v8 pistons and remove material to match desired height. alas.
If this is going to be a driver, you might consider propane pistons. They will raise the compression but not like flat tops at zero deck. A good street combo is the propane pistons and a 270 rv camshaft. Hope this helps. Hud
Every time I look for them they are "out of stock". Do you have info on who has a set? Wow- just checked summitracing and Lpg cast pistons are in stock http://www.summitracing.com/parts/slp-980p30
Yep, he beat me to it. One can't ***ume that we automatically know what 292 you are working on or why you have the need to lower the compression on it as both the Ford V8 or GM six 292's weren't high compression engines stock.
MR 48 I want to raise compresssion without spending700 on a set of out of stock pistons. And thank you for your reply.but if lpg pistons will get me there and not cost more than the cost of the motor. To be be honest the motor has 50k on it and was told it runs superb. perhaps I should not mess with the pistons? And just do some head work.
The pistons for the 292 is the main drawback to people wanting to do a rebuild. A 292 in stock form makes 300 ft lbs of torque starting at around 1800 RPM and remaining there until around 3200 RPM or so, and will be fine your purpose. So just leave it alone and enjoy it the way it is since money is a problem.
Or there is this option :http://bangshift.com/blog/watch-a-1936-chevy-pickup-with-a-turbocharged-chevy-292-inline-six-make-nearly-900-hp-at-the-tire-and-run-160-mph-at-the-drags.html
You could do a milder version with less boost and retain your stock pistons,probably pick up some MPG as a side benefit.back in the mid 70's I worked at M&M Speed in Sacramento and we sold several AK Miller turbo kits.
now your talking, just freshen it up with new gaskets and the like put on a 4 bbl and headders and you will be happy with the results.
I have headers and a weber 38. I just need to pick up another carb and manifold. maybe just lump port and call it good. Off topic but anyone know if I have to cut the firewall or reshape the pan to accomodate the transmission
What transmission do you mean? The 2004R would be a good swap it is smaller and easier to fit and has .67 overdrive to perk up MPG.
I have a 292 that ended up with a .030 deck on the head lump ports flow ported over size valves .550 springs and that cost over $2000. The bottom end has gas pistons and it will be around 11/1 compression. Just so you know for street it is recommended to use the Offy over the Clifford with the water cooling. Split headers are a big plus too. I also had a head built for a turbo that is in the wings. It always takes money for any of this so stay conservative.
I mean the 700r. are there fitment issues with the existing area for the trans. will it have to be enlarged. I thought 200 because it is smaller but Tom Langdon recomended 700r, so I do not know which would be easier.
For towing, an OD auto is complications you don't need. Use what you've got or get a truck 3-speed automatic, gear it for cruising and let the low speed torque and the torque converter get you off the line. jack vines
Quality USA made forged pistons offered here for the Chevy 250-292 . The 292 pistons are custom made with a taller compression height to eliminate the excessive cutting of the deck for zero decking. http://12bolt.com/250292_products/pistons They come with rings. I use them all the time. Those Speedpro pistons are heavy, expensive and do not come with rings.
My mistake I have a turbo 350 that needs to be rebuilt. Would this be good set up for my intended purpose. I have heard they can fail under heavy torque
Wow bud a set of pistons for $124. Makes me worry. But you can't always judge by the price alone. Thanks for the link
I think all stock type replacement pistons for the Chevrolet 292 six cylinder engine will be dished. If you just want to bump up the CR, why not swap to a 194 six cylinder head, casting number 3864883, and have it milled. That particular head has the smallest combustion chambers of the 194-215-230-250-292 family of sixes cylinder heads. If I remember correctly, when I did this back in about 1976, with a 250 CID six, I had the 194 head milled .060. You could also deck the block some, the pistons are probably about .025 in the hole to start with. Check E-Bay for pistons if that's the way you decide to go; sometimes you get a good deal. Butch/56sedandelivery. There's a set of .020 over, 292 pistons for $89.00 BIN on E-Bay right now; beat that. There are also standard sets for $115, .030 for $105, .040 for $115, and .060 for $105; again, that's darn cheap. They are all cast pistons, and name brand.
Use 194 cylinder head . All Chevy straight 6 heads back then are interchangeable with little tweaking required. All the cylinder heads are around 74 cc ***bustion chamber ,somewhere in that ballpark , except the 194 which is around 61ish for the ***bustion chamber
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