The two fastest cars I owned personally...and it was a close tie...was a 72 TransAm 455HD (not HO) that was originally a Michigan dealers dragstrip car, and a 63 Valiant convertible i put a 426 Hemi dual 4bbl & 727 combo in.

quote Originally posted by rogergarrison: The only thing that makes sense to me it was not the same engine in the Buick, but a Pontiac version of it, and they just used the Buicks turbo system on it.

The Pontiac version of the GN engine used later model 3800 series heads in order to fit the Trans Am engine comparment. According to magazines of the day the Pontiac version had a superior head design than the one used by Buick. Pontiac's factory rating of 250 horspower was actually over 300. While I drove both the GN, and Turbo Trans Am new, I never did see them race side by side. I do remember beating a pretty strong 455 4-speed 70 GTO with my 86 Turbo Buick demo at the drags. My car still had the window sticker on it at the time. The Turbo T/A's seemed very quick too. We only got two so I was not able to drive one as a demo. I did get to show it to the customer that ended up buying both T/A's. I remember seeing his eyes go wide open when the boost hit. I knew i had the sale right then.......

[This message has been edited by Rick 88 (edited 05-26-2014).]

quote Originally posted by California Kid: Quote: Back in the 60's they didn't do flat out test for top speed and advertise it because of Insurance going through the roof any time the speed showed over 100 mph. 1969 RAIII 400 Hiden Pontiac Spec chart for GTO and Judge Performance figures (with 4 spd) Power 365.5 bhp / 272 KW @ 5100 rpm (366 advertised) Torque 603 Nm / 445 ft lbs @ 3600 rpm BHP/Liter 56 bhp / liter Power to weight 0.26 bhp / kg Top Speed 200 km/h / 124 mph 0-60 mph 6.5 s ((( Note posted RAIV listed Top Speed at 124 for insurance when it would do over 130 easy)))

That 1969 engine put out something like 310 bhp and 375 TQ net.

Here are the figures from my daily driver Solstice (I admit to it being slightly warmed over):

350 bhp, 375 TQ,
BHP/Liter 175 bhp / liter
Power to weight 0.26 bhp / kg
Top Speed 155 mph
0-60 mph 4.8 s
1/4 = 12.99

And the modern Pontiac also went around corners very well indeed. Too bad they never had an engine like that to stick in the 88 Fieros!

quote Originally posted by Rick 88: The Pontiac version of the GN engine used later model 3800 series heads in order to fit the Trans Am engine comparment. According to magazines of the day the Pontiac version had a superior head design than the one used by Buick. Pontiac's factory rating of 250 horspower was actually over 300. While I drove both the GN, and Turbo Trans Am new, I never did see them race side by side. I do remember beating a pretty strong 455 4-speed 70 GTO with my 86 Turbo Buick demo at the drags. My car still had the window sticker on it at the time. The Turbo T/A's seemed very quick too. We only got two so I was not able to drive one as a demo. I did get to show it to the customer that ended up buying both T/A's. I remember seeing his eyes go wide open when the boost hit. I knew i had the sale right then.......

That still dont explain (if Pontiac was superior) why the Buicks were faster than the TAs. Like mentioned already, BGN was the fastest production street US car at that time...why not the lighter TA instead.....? Was my own experience just a coincidence that the Buicks stomped our TAs? We had them when both were relatively new 1-2 years old. After getting beat too many times street racing in my TA over a few months, I sold it. While I know my 4bbl 455 TA was modified all thru, it would totally kill my turbo one...like racing a Corvette and a Cavalier.