Motor Opinions...

[454muscle]

1. More reliable than the 305, especially the 350 and 400.

I was agreeing on everything you said except this. How does one figure an engine's reliability?

My bad. I dunno why I said 305 there. It should only be 350 and 400. 350s are known to break, and the 400 small block heads tend to run hot, even with steam holes drilled into them. Not to mention the longer stroke in both motors can put more stress on the mains and bearings. But I'm no expert here, just what I've learned over the years (others can chime in here, or by all means tell me I'm wrong).

The 455, if just a stock rebuild will tend to have less of these problems, with power and torque to spare.

 

[84cutspreme]

I put a 350 in my cutlass. I love it...but my pops has an 87 cutlass with a 455. The phrase already used on this post says it all...There is no replacement for displacement! Only downside is parts selection really. That and I thought my fuel mileage was bad lol.

 

[jrm81bu]

1. More reliable than the 305, especially the 350 and 400.

I was agreeing on everything you said except this. How does one figure an engine's reliability?

My bad. I dunno why I said 305 there. It should only be 350 and 400. 350s are known to break, and the 400 small block heads tend to run hot, even with steam holes drilled into them. Not to mention the longer stroke in both motors can put more stress on the mains and bearings. But I'm no expert here, just what I've learned over the years (others can chime in here, or by all means tell me I'm wrong).

The 455, if just a stock rebuild will tend to have less of these problems, with power and torque to spare.

I didn't know that 350's are known for breaking(yes i'm being a smart *ss). And none of my 400's have ever ran hotter than any of my 350's. Now since the longer stroke seems to be an issue, i think that would mean the 455 is the most unreliable out of the above mentioned engines, since it also has the longest stroke.

 

[87PontiacGP]

I'm in a similar boat, only I am either going with a Pontiac 400 or 455. I've searched around for the past couple weeks and I'll be damned if I can find a Pontiac 455.. 🙁 There getting hard to come by. Though, a 455 would be great fun with all the excess torque, a Pontiac 400 would be a great alternative, I think. They make great torque numbers, even if lower than a 455, and would be different than a regular 350 engine. From what I have read thus far, though, is the 400 doesn't like high compression. However, it makes great power numbers from, what seems like on other engines, to be small amounts of compression.. With around 8.5:1 - 9.1:1 compression, I've read people making (guesstimated..) around 300-400+hp and 430-470+ lb/ft of torque depending on the application.. I don't know about you, but that's plenty for my needs with the car as a daily driver.. 8)

So, in a nutshell, if you can't find a 455, I'd go with a Pontiac 400. Readily available, and can make pretty good power figures.

 

[565bbchevy]

I thought the OP was referring to 305 sbc or 350 sbc and then the choice other than that was a 455 Pontiac and when the 400 was mentioned I was under the impression we were still talking Pontiac which would void any of the running hot rumers.
And on the subject of 400 sbc running hot I disagree with that also, I have build a few 406's and never had an issue with cooling if it was built right to begin with,of coarse with steam holes and has a proper cooling system to support it then there are no issues.
Now if you drop a 406 sbc in where your stock 305 sbc was and use its cooling system that might be a problem since you just added 100 cubic inches and most likely some performance parts so you would have to expect upgrades for the cooling system also.

 

[mightymouse]

455, but anything pontiac would be cool.

 

[454muscle]

I didn't know that 350's are known for breaking(yes i'm being a smart *ss).

No need jrm81bu. Like I said, and I repeat, I'm just saying what I've learned and was told (mind you, from an engine builder) and I did say that I'm no expert and that anyone can chime in to tell me I'm wrong -- just in case you missed that little bit.

 

[Bonnewagon]

I've abused almost every motor Pontiac ever made from OHC6 to 455. Those long stroke torque monsters were designed to move several tons of land-yacht with style (421, 428, 455). But the most famous and loved Pontiacs (GTO, Trans Am) were equipped with 389's and 400's which share the same 3.75" medium stroke as do even the fun little 326's and 350's. As a Pontiac enthusiast for almost 40 years, I still gravitate to the 400 as my best-bang-for-the buck kick-*ss motor. It just feels, right. Especially in our lightweight cars.

 

[lvngded]

IMHO any Pontiac engine would be smokin. But aside from giving us some numbers, 350, 400, 455, you haven't put out any more information. Let everyone know what your goal is, and the folks here can help you get there.
I just started my project after doing a bunch of reading, and I am no expert, but alot of good people in alot of messages gave me the following advice. All of this is assuming that you want to use a Poncho motor.

1) The aftermarket support for Chevy & Ford outnumber the Pontiac at least 5 to 1. So while you will most likely find the parts you want, you won't find them as cheap.

2) Pontiac changed the blocks in 1970 from having 2 hole for mounts to 5 holes. I have also heard of 400s with 3 holes. Either way, if you end up with a 69 or earlier block you will need an adapter for it. One of the members turned me on to Butler performance for this. Good people there, lots of experience and very nice too.

3) Many brackets will transfer from the 301 to your new powerplant, as well as hoses I believe.
I can't say which for sure, the engine I have came with all of them. But the motor mounts will be something you need to look for.

4) I have read quite a few posts about headers and exhaust in general. There is a guy who makes a set for our cars with Pontiac, both D & round port for $500. I can't remember his name off the top of my head. But do a search here and you'll find it.

5) This has been said already, but it warrents being said again. Work backwards, decide what your goal is and figure out what you need to get there.

Thats all I got, if anyone spots an error in what I said, please chime in. Like I said, I just started and I am no expert.
Good luck and have fun.

 

[Kato Asmodeus]

Wow, Before I Say Anything, I'd Like To Say Thank You All For Taking The Time Out To Read My Post And Respond...
This Forum Is Awesome!!!... 😀

Now Yes, You Guys Are Right... I Should Have Mentioned What I'm Looking To Get Out Of The Car...
Well Honestly, I'm Not Looking To Race It Or Anything Of The Such But I Do Want To Know That I Have Great Power Under The Hood And I Definitely Want To Feel It... I Do Know For Sure, That Horsepowerwise, I Want No Less Than 400... So 400 And Up Is What I'm Looking For... As Far As The Motor, I Don't Want Anything Used Or Rebuilt... I Plan On Purchasing A Crate Motor So I'm Just Looking At A Couple Of Companies To See Everything They Offer...
I Never Even Thought Of A 400, Which Does Indeed Sound Great As Well... However, I Did Fail To Also Mention That Since Altering And Modifying The Chasis According To The Power Of The Motor Is A Major Factor In Deciding Which Drivetrain To Go With, I Want As Much As I Can Have With The Least Amount Of Modification To The Chasis As Possible...
I'm Looking To Keep The Car As Original As I Possibly Can, Just With More Power Than It Was Born With...
As Far As Suspension Goes, I'm Also Undecided... I've Heard Different Things When It Comes To Polygraphite Suspension Componants, Some Good, Some Bad... Anyone Have Any Useful Info About These From Personal Experience?...
If Not A Polygraphite Suspension System, I Was Thinking Air Ride...
Now When It Comes Down To Body, Paint And Interior, I Want To Leave The Body Completely Original... Trim, Vinyl Top And All That... Paint, I Want To Go With The Original Maroon Color It Was Born With Or Something Extremely Close... Interiorwise, I Want To Keep It Original Other Than Covering The Seats In Leather...
Oh And Yes, Dual Exhaust Is A Must!...