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Discussion Starter · #1 ·
Going to look at an extra motor for the boat. Anybody know, was the 1970 455 olds GT engine a flat-top piston originally? I recall most of them are flat but I think a couple of years may have had scooped?
 

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Discussion Starter · #3 ·
sorry I do that sometimes, the GT is the Rocket. My Dad always refers to them as the GT motor so I always do as well.

I'm just going to need to order some parts and doublecheck some things and cant remember if they had flat top pistons.
 

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Discussion Starter · #7 ·
The GT is referring to the fact that the motor came out of a 1970 Olds 455 Toronado GT - which was not just a ford thing:

"Of the 25,433 Toronados built in 1970, only 5,341 were Toronado GT models. The GT provided a 455 cu V8 of
400 hp, up 25 hp from the standard 455. A 400165 performance cam and special torque converter gave this Toronado 0-60 times of 7.5 seconds and a top speed of 135 mph. Dual exhaust with a notched rear bumper and nugget gold metallic paint with black wheel arch pin-stripes and the GT hood badge, further identify the GT."
 

· AKA OhOneWS6
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The GT is referring to the fact that the motor came out of a 1970 Olds 455 Toronado GT - which was not just a ford thing:

"Of the 25,433 Toronados built in 1970, only 5,341 were Toronado GT models. The GT provided a 455 cu V8 of
400 hp, up 25 hp from the standard 455. A 400165 performance cam and special torque converter gave this Toronado 0-60 times of 7.5 seconds and a top speed of 135 mph. Dual exhaust with a notched rear bumper and nugget gold metallic paint with black wheel arch pin-stripes and the GT hood badge, further identify the GT."
I almost asked if that is where you got the GT from. The 455 rocket was available in other models as well.
 

· Jet boat service
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The 455 Rocket motor came in two versions as far as the piston goes. The low compression engine ,8.75 to 1, had a deep dish piston, I believe around 22 cc's deep. And the high compression version, 10:25 to 1, had a shallow dish of around .014 cc's deep. Heads were around 79 to 82 cc. There were different power options of course, using different carb, cam and exhaust combinations. Actually, I just checked, and the deep dish was a 39.5 CC cup, .306 deep. Jim :):)
 

· Sit N' Spin
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The 455 Rocket motor came in two versions as far as the piston goes. The low compression engine ,8.75 to 1, had a deep dish piston, I believe around .022" deep. And the high compression version, 10:25 to 1, had a shallow dish of around .014". Heads were around 79 to 82 cc. There were different power options of course, using different carb, cam and exhaust combinations. Jim :):)
Dr Olds has spoken :D
 

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The 455 Rocket motor came in two versions as far as the piston goes. The low compression engine ,8.75 to 1, had a deep dish piston, I believe around 22 cc's deep. And the high compression version, 10:25 to 1, had a shallow dish of around .014 cc's deep. Heads were around 79 to 82 cc. There were different power options of course, using different carb, cam and exhaust combinations. Jim :):)
Solid info above here , almost embarrrased to admit my first line Mechanic job was at and Olds dealer in the very early 70's ;)
 

· www.highflowdynamics.com
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Going to look at an extra motor for the boat.
Got one almost ready to go over here. Fresh bore, Speed-Pro forged pistons, balanced, CompCams hyd flat tappet cam, Cloyes roller chain, polished Edelbrock intake, HV pump, 10-quart Milodon pan, adj valve train, MT valve covers, etc. Photo documented, everything new and unfired. Will be completed before the week's end.

Call, email, or PM if interested,

LO
 

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Discussion Starter · #15 ·
The 455 Rocket motor came in two versions as far as the piston goes. The low compression engine ,8.75 to 1, had a deep dish piston, I believe around 22 cc's deep. And the high compression version, 10:25 to 1, had a shallow dish of around .014 cc's deep. Heads were around 79 to 82 cc. There were different power options of course, using different carb, cam and exhaust combinations. Actually, I just checked, and the deep dish was a 39.5 CC cup, .306 deep. Jim :):)

Now that's what I was looking for, thank you VERY VERY much! You guys never fail to amaze me with the amount of knowledge on this board.
 
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