[ShihanJim]

Alt & Steering Brackets

I have a 77 Trans am and looking to put a 670 or 12 heads on the 400. The original bracket of the 77 Alternator and power steering will not fit. The bolt that has to go thru the Alt bracket, alt, sleeve, Steering bracket to the top of the head is not there to the 670/12 heads.
Is there a alternative bracket to install the Alt/Steering or will a bracket system for a 1970 Pontiac 400 fit?

[Skip Fix]

Brackets and pulley offsets are a match so bracket for a 70 will need 70 pulleys.

My SR RAIV heads had the boss for that cast on so we could drill and tap it when I had them on the 78 TA.

['ol Pinion head]

'70 1/2 Firebird V8 accessory brackets & matching pulleys would be one solution but will be expensive. The main thing you have identified is when installing '67-70 big valve (or converted late 60's small valve heads) on 71+ Pontiac V8's, these earlier heads don't have the top accessory bolt hole, the one for the long alternator bolt on '71+ 10SI alternator/PS bracket setups. Instead there is just a curved area there & no material to drill & tap.

Have detailed before how several times I've taken the common style '71+ Alt brackets & loaded PS setup, & on the long alternator bolt, trimmed it down by a few threads. Then I then flipped the long bolt around backwards. End up using a plastic insert style locking nut at the front pivot hole where the end of the long alt bolt comes through the large front alt mtg plate. Little cumbersome to do by oneself in a car (can use the cherry picker & a thin fabric ratchet strap if you don't have help). This is with the most common 71+ Pontiac V8 Alt & PS brackets, not a '71-76 Pontiac V8 running the large 80 amp 27SI alternator.

The flipped long bolt trick works well for solving this issue, and with properly tensioned belts you may go years without any need to remove the alternator or PS pump. When I was a teen, I was bad about over tightening the alt belt & all that did was eventually take out the wp & alt bearings, lesson learned.

Welcome to PY board!

[ShihanJim]

Thanks Skip Fix, my 77 400 had a 6X8 head and wanted 670 or 12's but the 77 brackets would not fix. I was wondering if I can get a set of brackets that be used on those 670 or 12 with the 77 alternator and PS?