[TRADERMIKE 2012]

This is the one you have been waiting for, a comprehensive detailed "way to build a Pontiac Engine" from the bottom, the up is done already, by the best on the PY forum. Look to learn something that you never knew before: "narrated by Mike", in real time. All are welcome and say what you want, here there are little rules, just have fun.

[462gto]

I would recommend getting the book in the link to get more familiar with the pontiac V8 and then find a good machines shop in your area that is familiar with pontiac v8s and If you don't know a good shop in your area start a new thread and ask the forum.

How to Rebuild Pontiac V-8s - Updated Edition (Cartech) https://a.co/d/gcTaxgc

[steve25]

Your jumping the gun here!

A build can not take place until it is known what the condition of your parts are and then in turn what may need get remachined or replaced!

The block and its internals need to go to a competent machine shop to be magnafluxed , looked over and measured for the needed tolerances.

Do not toss out the old main and rod bearings as they can give a clue to the machine shop as to what may or may not be going on with the motor.

I might not be a bad idea to hook up with other Pontiac folks down there who have successfully built a few Pontiac motors, especially if what they have built has lived through the rigors of racing .

If you have not joined one of the many Pontiac clubs in Fl then that would be a good start as many of them have knowledgeable tech people in there ranks.

[Cliff R]

Engine building involves close attention to detail, careful parts selection, and exact precision, at least if you want it to lead a long heathy life.

Right to start with assume nothing. Those heads that you had done aren't going to make the grade so plan on stripping them completely down and having a full set of guides put in them and new one piece valves, springs, etc. You can retain the Pontiac retainers and locks, nothing out there is any better and most of the aftermarket stuff considerably heavier.

Toss that POS low end 3 keyway timing chain set in the nearest dumpster as well.

I'd re-use the crank and outfit the engine with a good set of forged rods and modern forged pistons (all installed in the correct direction and orientation). Modern forgings with the right alloy can be ran nearly as tight as cast pistons and you get the better ring packs, much stronger parts and full floating so you don't have to "cook" the rods to press the pins in place.

I'd stick with a flat tappet cam but insist on USA made lifters. If Comp is DLC coating them even better. The last couple of flat tappet engines I did here used camshafts that I sent out to be "coated". It's an ion-bond process and they come back looking like black chrome plated. Without any oil at all they claim lubricity equivalent to using 5W-30 motor oil. In any case it's cheap insurance and for the couple hundred bucks it costs if nothing else you'll sleep better at night.

Plan on balancing the spinning assembly, and decking and squaring the block. Meaure the bores and locate good pistons in the desired over-bore size. During that deal establish tight quench (.035-.040") and the true static compression ratio so you can make the right cam choice so it runs fine on this new fuel.

I've done more of these engines than most who will read this, and push for higher compression which makes more power at every RPM and allows for more camshaft with less negatives, so NOT part of the "lowering compression for pump gas then turn right around and install some short seat timing fancy whiz-bang lobe profile cam to get some of the lost power back" crowd.

Like your way too long running thread on the FUBAR'D engine still sitting between the fenders you'll get a LOT of advice. Mine is simple and aside from a few upgrades with better rods/pistons/ring pack I'd keep it simple and fairly close to "stock" in many areas.

I am NOT a big fan of roller rocker arms and have found most to be nothing but pieces of bovine excrement so stick with stock stamped steel with solid balls in them for most "mild" builds done here. If you go aftermarket the only ones I'd endorce are Crane Gold Race (not even sure if you can get them these days), Harland Sharp, or Crower Enduro. ALL others I've tried have failed someplace in long term service. Ya I know, lots of folks use all sorts of these imported junk rockers w/o issues but here I've have issues with everything that isn't listed above.

I think what we see with this engine building thing is that few of these engines see very much actual time on them these days. Most owners take them out on a few nice Sunday afternoons for a burger and a coke, maybe hit a local Dairy Queen car cruise once or twice, and might stop by their local track a couple of Friday evenings for a "test and tune" session. A reality check is in order there for evaluating parts. 300 miles a year vs several thousand or more isn't going to tell you if anything that you used makes the grade.

Not only did I build engines for almost half a Century I've had scores of them driven (usually limped up here), towed, trailered and dragged up here with issues right after "fresh" engine installs and NOTHING was working well. So I get to see these things at a user level and get to see what happens when poor choices are made and lack of attention to detail, using crappy parts, and poor attempts at establishing optimum timing and fuel curves to insure a good end result.

In any case after many years of your engine not making the grade with mulitiple unsuccessful attempts to get it up to par, it's certainly time to remove it from the vehicle, open up the wallet and give it the time and attention it desperately needs.......IMHO......

[grivera]

Great thread and I look forward to your updates.

Good advice from others already.

When you get the block and crank back from the machine shop don’t assume it is clean enough for assembly. Wash with hot water and soap, use rifle brushes to clean passages and keep cleaning until no grime appears on a paper towel. After cleaning spray machined surfaces with WD 40 to prevent flash surface rust.

If you choose to go with higher compression make sure you know how to tune the AFR and timing to accommodate and of course consider what octane fuel is available to you. Plenty of threads for you to look at here to assist with that. This is an area where EFI will help as you can dial everything in precisely.

Good luck with the build!

[jhein]

[steve25]

I have a feeling your gonna need more then 1 pan of Jiffy pop!

[Kenth]

If you keep the thread objective, maybe it will be as you wish.

[Dragncar]

Keep it simple, listen to Cliff and you will be fine.
Make it over complicated and over think things and you will create your own problems.

[Schurkey]

Schurkey says

You've rebuilt a TH400, successfully as best I can tell. You discovered issues with the main shaft that I didn't know existed; therefore you were clearly paying attention.

The engine will be "similar but different". A TH400 is about the easiest 3-speed transmission on Earth to overhaul. An engine will require more special tools, more contracted-out remachining and inspection, and similar care in disassembly, cleaning, inspection, and reassembly.

[PAUL K]

Build back better!

Paul K out

[tom s]

Been doing this stuff for more than 60 years.My thought for Mike is to find a good machine shop that builds engines and have the short block built.Get a shop with good recommendations that will document all the numbers as far as clearances.Take it home and finish the build and break in.Find one CLOSE that you can stop by and watch the progress.JMO,Tom

[mgarblik]

In my opinion, if you decide to build your own engine, you need two things: 1. A good book to take you step by step through the process. Either of the Rocky Rotella books would be great. Readily available. Jim Hand has an older book as well. 2. A machine shop with a GREAT track record that doesn't treat working on a Pontiac V-8 as being the evil, bastard stepchild of a Chevy. Some basic measuring tools, a clean work area, and a few low cost building tools and your all set. Good luck.

[hojs69]

Title seems to be asking The Forum, if you should build it yourself.

I vote "no." Find a qualified source.

[Formulajones]

There ya go Mike, an engine dedicated thread. Now everything found wrong can be corrected and documented in one place.
Take the engine to a highly recommended shop for a tear down and inspection and report back what they found. Go from there.

[dataway]

Build more.
Type less.

[jhein]

No offense to anyone, but I think if a person needs to ask if they should take on a project like this, then they probably shouldn't.

OTOH, if having the motor done right the first time is not the priority and you are more looking for the learning experience and don't mind too much if you have problems along the way and maybe even a motor that fails, then go for it. But, if I were gonna do that, I wouldn't use any sort of rare or valuable block to learn on.

[P@blo]

I'm still confused how engines were ever built properly before the internet? I mean, everything that we would have left on the table during those dark times...

Find a good machine shop and listen to what they tell you. Then spend a bunch of money and save a lot of typing at the same time.

Unless this is more of a memoirs thing for you and David Carradine.

[i82much]

If I were contemplating building my first engine, I would get a junkyard Chevy 350 and do a cheap cast rebuilder piston job. Learn how to measure and assemble. If that went well and after driving it for a few years, I'd sell the Chevy and try doing something like a 428 build. But no way I'd start off with something like a 428 block on my first build. Walk first, run later.

[mgarblik]

Originally Posted by i82much

If I were contemplating building my first engine, I would get a junkyard Chevy 350 and do a cheap cast rebuilder piston job. Learn how to measure and assemble. If that went well and after driving it for a few years, I'd sell the Chevy and try doing something like a 428 build. But no way I'd start off with something like a 428 block on my first build. Walk first, run later.

I would respectfully disagree with a Pontiac being any more complicated or difficult in any way to rebuild than any other V-8 vintage engine. Most of us really like the 428 engine. It is a great one, but hardly rare. It was the BASE engine in all 69 Bonneviles. So there's 90,000 units. It was optional in all 1967-1968 and 1969 full size cars. So a reasonable estimate is 200,000-250,000 units? It's the same process to rebuild as any 326-455 Pontiac V-8 with the same costs involved. As mentioned in my previous post, with a good book, a good machine shop, and some basic builders tools, I just don't see any problem. The OP seems to have successfully rebuilt a three speed automatic transmission which IMO, is way more complicated than a gasoline engine.