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#1
11-28-2023, 02:23 AM
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Can anyone identify these pistons?
Hi, I was wondering if snyone could help identify these pistons? When I ran the number L2262 on the internet, the closest similar were Speed Pro forged. These have been in this motor since at least the mid 90s. Any help is appreciated. Thank you.
Last edited by bob prichard; 11-28-2023 at 02:44 AM. |
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#2
11-28-2023, 04:57 AM
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Yep, look like Speed Pro to me.
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#3
11-28-2023, 07:05 AM
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Yes they are the 2262.
They use friction producing factory size 5/64" compression rings. The 4 valve notches total up to 6.7CCs if I recall right. They weight about 680 grams and use a very heavy 250 gram wrist pin. There compression height should give you about 020" deck clearance if the deck is untouched from the factory height and your Rods center to center are all about the same.
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Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
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#4
11-28-2023, 08:58 AM
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+0.030 TRWs. Pro amatauer tip; don't use the heavy pins. Reuse the factory pins.
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#5
11-28-2023, 09:09 AM
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Those pistons end up pretty far down in the holes at TDC, and HEAVY parts.
Good tip on putting much lighter pins on them. Being an older alloy they need a little room that modern forgings. We used them WAY back in the day when that is all there was, today those are door stops far as I'm concerned as there are much better offerings out there these days.......FWIW.....
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If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
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#6
11-28-2023, 11:41 AM
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Thanks for all the info. They are in my low mileage 67 Firebird 400 motor that was rebuilt in the 90s, and they may have been in even longer than that. If I were pulling the long block they would get changed. Thanks again for all the information.
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#7
11-28-2023, 04:11 PM
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[QUOTE
They weight about 680 grams and use a very heavy 250 gram wrist pin. There compression height should give you about 020" deck clearance if the deck is untouched from the factory height and your Rods center to center are all about the same.[/QUOTE] Mid summer I replaced the cast 8 vr pistons with these. Measured at .026 in the hole. Pins were 195 grams. I wanted to use the icon 150 gram pins from Butler. The pins I got were .250 shorter and 194 grams. Sent them back. Guy at Butler said probably got wrong pins from Icon. He also said the thicker wall pins are stronger.
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Frank M. 75 Firebird 68 Firebird 400 RAIII 66 Chevy II 461 Pontiac in AZ |
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#8
11-28-2023, 04:39 PM
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The 250 gm pins barely have a hole!
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Skip Fix 1978 Trans Am original owner 10.99 @ 124 pump gas 455 E heads, NO Bird ever! 1981 Black SE Trans Am stockish 6X 400ci, turbo 301 on a stand 1965 GTO 4 barrel 3 speed project 2004 GTO Pulse Red stock motor computer tune 13.43@103.4 1964 Impala SS 409/470ci 600 HP stroker project 1979 Camaro IAII Edelbrock head 500" 695 HP 10.33@132 3595lbs |
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#9
11-29-2023, 04:35 AM
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The set I bought a few years ago came with lighter pins. The set I bought 40 years ago had the heavy pins. I don't think they've come with the heavy pins for about 20 years now.
So if you think the pistons were installed a long time ago, probably heavy pins, if they were replaced in the last 10-15 years .. probably the lighter pins.
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I'm World's Best Hyperbolist !! |
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#10
11-29-2023, 08:25 AM
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Yes, at some point thank God the massive 250 gram pins did get changed over to the ones that where being used in the L2359F 455 replacement piston, and these are 192 grams.
__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
| The Following User Says Thank You to steve25 For This Useful Post: | ||
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#11
11-29-2023, 09:16 AM
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Yea, my hobo trick was to use Stock used 455pins in new TRWs for 400 (428? Too) builds (80's-90's). PAW was the deal at ~$145/ for a set of 8.
Last time i bought TRWs, they were "Speed-Pros"and all kinds of fancy laser coated skirts, and Stock-like Pins. Forged slugs these day look spendy. |
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