been working on the merc in my avitar as of lately, i originally purchased a 322 nailhead to go in it but since i have acquired a 58 pontiac 370 tri power engine and am really considering using this engine instead. i see a lot of nailhead's being used but not alot about these pontiac motors,is there a reason? i know maybe one reason because i don't see many performace parts for sale for them. if you have ever built/used one please some info on them or tell me why i should/shouldn't use it. my thought was there's no replacement for displacement. school me on this.thanks hot rust
I reckon you should go with something a little different then. According to http://www.enginefacts.com/pontiac370.php (the first thing I googled - meaning, I don't know whether its a reputable source )they are pretty unique to that year. Might be hard getting parts for, but, hey, what the heck?
Myself I would go with the pontiac. the pontiac will make more power than the nailhead. I have a 55 GMc with a factory 287 pontiac engine. i also have a 56 322 and a 401 nailhead. the nailheads are limited by the poor design of the heads. your 370 tri power can use later camshafts. iginition even swap the heads if you want. stick shift flyweels bellhousings are hard to find for the early pontiac. 60 and later blocks are different.
I'd vote for the Pontiac. That 370 is a very stout block and has loads of potential. (Some Pontiac fans claim it's one of the best they made.) Parts aren't that hard to find, but it does utilize a front engine mount under the timing cover and then two on the bellhousing. That might be a consideration for how you are going to mount it.
[pontiac 58 370 has the same bellhousing as 1959/60......i.e. 1958-60 are the same....change came in 1961
Poncho motors have a rather stout bottom end,...and there was a lot of factory "goodies" available, until into the early 70's. I would definitely go with one. 4TTRUK
Poncho. End of discussion. I've had 3 58 Pontiacs and of those two had Tri Power. Nice engines and they hauled those aircraft carriers along very well, besides you rarely see them so the cool factor alone works for me. Like has been posted before, have fun finding stick shift stuff for one but Bendtsens may make an adapter. Posted using the Full Custom H.A.M.B. App!
Here is my engine builder posing with the mill for my '34. This one is a 462 inch 389, but yours will look pretty much the same. And, yes there are plenty of speed parts out there. Good luck, -Abone.
Here is my same engine builder a few years ago standing by the engine in my daily driver. She has won a **** load of races, no Buicks have even come close... Actually, I'm just poking the Buick guys with a stick. The Nailhead is a hell of a good engine and would be a great choice for your hot rod just as much as the Poncho. (but the Pontiac would be faster....) -Abone.
thanks guys, i thought it might go this way with the pontiac, in the merc however i want to run an automatic ******, the 322 already has a benstead ****** adapter, so i guess they will get contacted again. i want to keep it simple, no billet and i thought maybe just some finned valve covers and nice air cleaners and use paint to detail out. what color were these engines from the factory? thanks hot rust
I have always loved the look & torque of Nailhead's, TV Tommy and all. But what does a Blue Oval guy know about GM stuff? In the July 2013 issue of Street Rodder magazine there is an a Tech article about "Poncho Power". Check it out.
I'm a Nailhead guy, and I'd go with the Pontiac in this case. No reasons that haven't already been mentioned. -Brad
55-60 Pontiacs had the same bell housing patterns, so you have two choices for automatics, unless you go with an adapter. Dual range hydramatic from 55 and some 56 Pontiacs, and the dual coupling hydramatic 56-60. If it were me I would be using the dual range hydramatic and the bell housing from a 55 or 56. I don't believe the 56-60 dc hydro bell housing will bolt to the dual range, but they might if you use the rear bell too.
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