[1stgenbird]

I have swapped a 455 into my Trans Am and am in the process of acquiring brackets to attach the alternator and power steering pump.
I have an alternator bracket that I'm told was used on the '70 GTO and T/A 455. The photo of the bracket attachment shows an arm of the bracket attaching to a bolt on the water pump. On my 455, I don't have a bolt in that location.
Were there different water pump styles in 1970 for the 455? The 455 I am using came out of a '70 Bonneville.

[goatless]

All '69 and up Pontiacs had the 11 bolt water pumps and will be interchangeable- the only oddball was the early '69 short water pump, but that still bolts up just the same.

[Held for Ransom]

I believe because of hood clearance, the 1970 Firebird line-up used different brackets than the other models.

['ol Pinion head]

Very early production '70 Pontiac V8 & P/S equipped A-B-G series used the same two piece alt strap set-up that was used in '69. The large black cup style '70 A-B-G alt bracket was introduced late in the Fall. Either style of these alt bracket will work with the '69 & later 11 bolt water pump & the '67-70 Pontiac PS V8 pumps. The '70 V8 Firebirds used their own set-ups, which require their own specific pulleys. I have had numerous 2nd Gen Birds with early big valve heads & the '71+ brackets, thus '70 Bird brackets & pulleys are not a must for the '70 heads.

other problem fit deals:
-There are some early aftermarket alum intakes that relocate the thermostat hsg & create a problem when attaching the original alt brackets. Been a long time but ran into that with a few P4B's.
-If you have a '68 timing cover & early 8 bolt waterpump, that could cause a problem too, as the small waterpump bolts are in different spot & will not line up with the '70 cup style alt bracket or the '69 front alt strap.

[1stgenbird]

Thanks for all the great info.
This 455 has the same style water pump and timing cover as my 67 Firebird 400 so it must have been swapped at some time in it's life. I will just use the two strap style alt. bracket as my 67 has.

[rexs73gto]

No don't do it , it will make your life harder . Reuse the timing chain cover & water pump from the engine your removing. Getting parts & lining things up will go a lot easier if you use the later modle timing chain cover & water pump. The 67 style pump & cover will not cool as well as the newer style cover & pump.

[1stgenbird]

Don't have an engine to remove. The TA had a Chevy 350 that was scrapped years ago.

[rexs73gto]

I hate to say this but it would be better in the long run if you would just buy another timing chain cover & a new water pump to be the correct on you need rather then try to piece it together with the 67 style. All the items you need are on the net or from guys here on this site , so please do this before you piece it together & maybe it'll work,,,, maybe.