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Lynxh
02-09-2004, 09:50 AM
Hi,
I was wondering if anyone out there can tell me the compression ratio 0f a stock 455 stage 1??

Thanks
Smartin
02-09-2004, 10:42 AM
What year??

70 and earlier was something like 10.25 to 1

71 and up was 8.5 to 1

They eventually dropped the compression on all their engines to 7.9 to 1
Lynxh
02-09-2004, 02:04 PM
I'm told that its a 1970 but am not entirely sure if that is true.Thanks
Lynxh
02-09-2004, 02:08 PM
Smartin would you happen to know what size the torque converter is for the stock transmission?? It's a 9" torque converter if that helps. Or if there are markings on the torque converter that will tell me.

Thanks,

Gerald
Smartin
02-09-2004, 02:12 PM
I have no idea on the convertor size, but 9" sounds right....at least I hear that size being thrown around here..:Do No:

If you can find a casting number on the block or heads, then we can find out what year it is.
Lynxh
02-09-2004, 03:32 PM
Alright,
Thanks for all the help Smartin.
LARRY70GS
02-09-2004, 06:04 PM
Lynxh said:Smartin would you happen to know what size the torque converter is for the stock transmission?? It's a 9" torque converter if that helps. Or if there are markings on the torque converter that will tell me.

Thanks,

Gerald

9":eek2: I don't think so. Stock converter for the BB trans behind a 70 Stage1 is more like 13" with a stall speed around 1600 RPM. Also, I believe someone cc'ed a stock 70 Stage 1 and compression was more like 9.8:1
Lynxh
02-09-2004, 08:19 PM
Mustn't be the stock converter than. The one that's with the transmission now is a 9" converter.
LARRY70GS
02-10-2004, 11:18 AM
No Buick ever came with a 9" converter stock. Are there any markings on it? 9" generally is a race converter with high stall speeds
Carl Rychlik
02-10-2004, 01:05 PM
Even though Buick rated the Stage 1 at 10.5 to 1,the actual compression was more like 9.8 to 1(as Larry said).

As for the converter,the stock Stage 1 was indeed 13 inches,and it had an ink stamp with two letters on it-I've forgotten what they were,but(" Buick Encyclopedia on two feet") Mark DeConti would be able to tell you what two letters were on there.
Lynxh
02-10-2004, 01:11 PM
Yeah there is a marking on the back of the converter that says 9".
Lynxh
02-12-2004, 03:46 PM
The pistons in the engine have a letter F after the serial number on them does this stand for forged??