A new set of pistons and pins, new in box. PN 50015.030 No rings Pictures attached. $300 plus shipping, PayPal
I need some historical information on these pistons. When I bought my 1970 Buick GS 455. I found out by using a borescope and taking photos, the previous owner (purchased this Buick in 2015). Sometime after owning this Buick he had these exact pistons installed. When I bought these Buick in 2021, I was NOT told this modification had taken place. After purchasing the Buick, I've been fighting dedonation issues for over 2 years. I've had a classic car shop in Northern Virginia working on this as issue. Plus I've had some other upgrades completed. What I need to know is everything you can tell me about these pistons. Compression ratio, cast or forged. From the photos they look to be cast. What year are these pistons designed and manufactured. Are they considered high performance? Another issue I have been fighting is high water temperatures, especially with A/C operating. Anything you can tell me about these pistons can really help me out. Do you happen to know if these pistons sit below the block deck. I know this engine has not been decked. I can't really don't know what the compression this engine is at without pulling the heads and taking measurements and I really don't want to do that. The original engine rebuild was sometime in 2012. That is prior to the previous who purchased the Buick in 2015. So, if there was another rebuild after 2015, there is no documentation of this possibility. So you can see why I call my Buick engine a mystery. This has been a huge problem for me and expensive to fix the dedonation and high water temperatures. Any and all information you can provide to me about these pistons will be very helpful. It's my understanding these piston are no longer manufactured. Thank you VET (Navy). This is my email if you need it. foywhite@gmail.com
Austin, it pays if I can read.lol Your pistons are forged. Also, they are hypertectic. Now I'am wondering if my pistons are the exact as yours? Not sure Kenny belle manufactured these pistons way back in 2015? I guess it's possible I might be barking up the wrong tree. I only have photos from a borescope but they sure do look to be the same. I hope they are. VET (Navy)
I have a set of KB lightweight forge Pistons 0.10 made by Jahns they look nothing like the top of these pistons. Mine Have a slight dish with two butterfly cut outs.
I had LarryGS70 look at my borescope photos and he identified them as the photos I looked at that Austin has his pistons for sale. I just checked Austin's part number with the part number that Larry has in his Kenne Belle catalog and they are identical part numbers. VET
Austin, sorry, this is my third post, I checked your part number against the part number I got from Larry70GS. Both part numbers are identical. Just want to let you know. VET
My understanding is these are rebranded speed pros. If they are like the speed pro forged, they are in the hole quite a bit and the block needs to be decked a good amount
That's good news. I say this because with the junk gas on today's market, I'm leaning towards CR in the 9 to 9.5. I was sweating I had some high CR pistons. I've been fight two major issues. Dedonation and high water temperature with A/C engaged. I know because my block has been bored .030, this only adds to more high water temperature issues. The shop has changed my entire ignition system (MSD) and a adjustable vacuum advance. This is something I have never seen before but it seems to be very cool feature. For the high water temperature. I now have a new radiator, new fan clutch, new thermostat (160*) high flow, a special coolant made for high water temperature conditions and a High performance TA water pump. The last two items will be installed next week. If this works, I will be very happy and finally have a daily driver. The pistons really had me worried. Thank you for the info. VET (Navy)
Here’s a couple pages out of the early KB catalog pistons in my engine are KB 60001 with a 1/16 ring package. Looks like those could be KB60003 pistons.
Yes, I have seen your ongoing questions with pistons and detonation. I wish I could offer some firm advice. I do know compression ratio is not determined by the piston. Several other factors are involved. The pistons I have for sale are wrapped in July 10th, 1990, Los Angeles Times, news paper. I feel that is near the build date, not sometime in the 21st century. Pistons are hypereutectic, not forged or cast. There's a truck load of info on application of all of these. I have included a sheet from what was in the box of these pistons. I guess Jim Bell wanted guys to have this information. Thanks for looking at the pistons, and good luck with your water temps and detonation.
Here is the copy that I got from Larry (the Wizard). If you look at the last bottom line, this is the identical piston that Austin (part# is identical to my part#), that's in my Buick. VET
Thanks Austin, all this piston issue and detonation issues have been a real headache. I think we now have a grip on it. YAA One thing I didn't tell you, I was very surprised when a compression check was done and the average across all pistons came out to be 180 psi. I realize this is only static compression, but I have never had an engine have this high of static compression before. Thank you very much for your information. As far as the manufacturing date goes, who knows where the previous owner of my car got these pistons from??? VET
Yes, they came out in the later catalog I’m glad I have the Jahns Pistons in my engine. 180+ compression
Good luck with the sale ! I don’t think someone could go wrong if they’re building some kind of nostalgia engine build.
I did a little research on the pistons. One of the members had mentioned they maybe rebranded Speed Pros. I took the number stamped into the piston H392P. At Summit the Speed Pro current number on their hypereutectic piston is H392NCP. It would seem they are tied to Speed Pro hypereutectic ,with the numbers so close, over 20 years apart.
Excellent investigation. You're right, those number are real close. I believe you are right on. Thank you Austin.
Careful reading too much into cracking compression numbers.... I've seen 200k 3.4l v6 gm motor crank well over 200 and seen 8 second cars crank under 150.........when the valve close will drastically effect this........if they close late they bleed off the numbers.....and if they close early the numbers can spike
That's interesting, because my camshaft profile is almost identical to a Stage 1. Never heard of a Stage 1 having 180 psi static compression. I guess there's always a first time. lol
