I've got a winter project!
I picked up a Pontiac 389 (Thanks Jade Grey for the correction), and I'm going to rebuild it.
it's a 1966

<img src="http://www.pushtovent.com/383/cherrypicker.jpg">

It's in pretty good shape.
<img src="http://www.pushtovent.com/383/driverside.jpg">
<img src="http://www.pushtovent.com/383/passengerside.jpg">
<img src="http://www.pushtovent.com/383/blockfromfront.jpg">
<img src="http://www.pushtovent.com/383/blockflywheel.jpg">

It came with pretty much everything.
<img src="http://www.pushtovent.com/383/headv_cover.jpg">
<img src="http://www.pushtovent.com/383/valvecoverhead.jpg">
<img src="http://www.pushtovent.com/383/rods_pistons.jpg">
<img src="http://www.pushtovent.com/383/carb_intake.jpg">

It's got a load of other little parts too.

I was told that when I send the heads out to get re-worked, that I need them modified to run un-leaded gas. Can someone tell me why, and what this means?

Do those pistons/rods look good enough to clean up, and re-ring?

How much does the average "Hot Tanking" cost for a block?

What is the difference between a Pontiac engine and a Chevy engine?

Will anything from my chevy 350 swap over to this engine?

Reccomendations?
This is still my daily driver. I want this thing to be rock solid. Lots of torque is a plus.

I'd say my rebuild budget is around $2,000 give or take.

 

You'll need hardened valve seats installed in the heads to use with unleaded gas.

There's no way to know if the pistons and rods can be reused without measuring them and the bores.

Pontiac and Chevy engines are entirely different animals. Nothing you have will interchange. A Chevy engine would have been a lot more cost-effective.

 

You might have a 1966 Pontiac 389 there.

Those cylinders look really out of round, but that might be a trick of the light.

The cylinder heads will have to have different valve seats to run unleaded gas.

The connecting rods will have to have their ends checked for roundness and possibly resized. Also have them checked for cracks. I would use new pistons.

There's a big difference between a Chevy and a Pontiac engine. Do some reading.

Hot tanking the block should run around $50

 

I know, but how cool to have a pontiac in my pontiac!???



I got the whole package for $75 so I'm alright with the costs.

I'll be rebuilding the 350 once I get it out, and maybe throw it into something. A 1988 Chevy Celebrity with a 350 modded to RWD? YES!!! (Probably not) dang!

Actually, I'd like to get a Iroc and and have matching 3rd Gen's, ohhhh man.

I know I'll need a new intake, and carb. (among other things)
Where is a good place to get parts for this engine?

 

How much of your $2000 budget will be eaten up by the new transmission you'll need to bolt to that thing?

 

hmmmm, 389 is probably it!

I see what you mean about being out of round. The cylinders/crank were sprayed down with lithium grease for storage. It looks like a light trick, because they looked fine to me in person, but I did not measure with a micrometer yet.

 

Actually, they made an all wheel drive version of the celebrity. Imagine my surprise.......

 

Uh-oh!

There's no way to make them work?

 

Bolt pattern is way different. Buick Olds and Pontiac (older, before the GM "corporate" motor) will work.

 

So I need to find an old GTO in a J-yard, and ****** the tranny? Did they have automatics, or should I just try to switch to a manual?

 

Yep, they had automatics. 3spd, and the BOP version of the 700r4. Changing to manual is a whole nother project......

 

that's what I was thinking.

 

What say we fix the subject line to spare the poor guy from any more abuse...

There are BOP/C dual-pattern TH350 cases out there. Otherwise, you'll have to get an adapter to fit the TH700 on the engine. Another option is to find a BOP bellhousing and convert to manual tranny.

Take a look over in the Engine Swap forum. There's an "Important/Useful Information" sticky at the top that discusses putting Pontiac engines into 3rd gens.

 

Thanks Five7!

 

All in a day's work.

I do, of course, accept "contributions". PayPal preferred...

 

Get a th-2004-r tranny they have a dual bolt pattern for Chevy and BOP.

You should have got a 455 though.

 

Wow. A 389 with a 2GC. That oughtta do something. You should be able to fix that with a different intake and 4MV of ThermoQuad. A lot of the 389s came with three of the 2GCs, but those intakes are pricey and the whole assembly was more of a gimmick than really for performance. A good 4bbl (see above) will do just as well if not better.

The bores are like that to clear valve faces.

I had Poncho V-8s for a while, and switched some time in the '70s. They generally had a little better flowing head as they came out of the box, but they are heavy. Parts are probably still available, but are likely getting harder to find as time goes on. Badger still has pistons, and I'm guessing TRW and many other will still turn them. Rods could be a bit more of a challenge.

 

Here's a possible (and much cheaper) solution :

http://store.summitracing.com/defaul...=egnsearch.asp

So, $2000.00 - ($54.69 + shipping).....

There may still be driveshaft fitment issues. Otherwise, not a big deal.

If you look in the engine swap forum, there's a sticky about installing Pontiac V8s in 3rd gens. Although I think it was centered around a 455, I would imagine it would help you avoid some other potential pitfalls.....

 

I was hoping something like that existed! Thanks a lot!

Five7Kid mentioned that other thread, I checked it out, and bookmarked it. I'm going to call a shop tomorrow to see what they reccomend. Summit seems to have a lot of stuff when I filter it for a 1966 389, so parts I hope will be available. I hear these things are torquey monsters, so I might need to be getting that Pro-Built trans sooner than I thought. That is unless I can keep my foot off the throttle when it's finished.

This is my first rebuild, but my dad's going to help me out, so I'm hoping March I'll have it on the road. Plenty of time to do it right, and keep the finances in order? Maybe while I have the engine out, I'll paint the car.

I read that the stock exhaust manifolds, while heavy, flow just as well as aftermarket headers. Is this true? (I can get those still)

Vader: "a lot of the 389s came with three of the 2GCs"
how cool would THAT look under the hood?
I think I'll just go for the one carb setup. I couldn't even imagine trying to tune 3 together at this time. Any suggestions for an intake/carb that would work nicely with the stock heads?

How about the valvetrain while we're in there?

Thanks for the replies!
-Chris

 

It'll be no more or less torquey than anything else of its size.

The stock manifolds won't flow anything like a set of headers.

 

Thanks for the explanation of the lip on the cylinder bore.

 

There are versions of stock Pontiac exhaust manifolds that generally flow well. However, these were limited production high performance parts installed on relatively few engines. (I.e. hard to find and expensive to buy!) These better manifolds didn't come on all Pontiac engines. For the budget you're trying to keep, I'd go with aftermarket headers. Fortunately, your 389 shares head designs with all but a few "special" Pontiac engines. So, any header that will work on the more common 350/400/455 engines will work for you. (Assuming you can get them to fit in the engine bay....)

It appears from the picture of the heads you attached you have "092" heads. (This is from the raised number(s) over the center two exhaust ports on the head.) You should know, if you don't already, that the 1966 389 with those heads had an advertised compression ratio of 10.5:1. (Ahh, the '60s. Back to the days you could get 100+ octane gas relatively cheap and easy....) Depending on where your rebuild takes you and your goals for the engine, you might want to consider a head swap or dished piston change to reduce the CR a bit. (I assume since this is your daily driver, you don't want to spend $5.00+ a gallon on racing fuel ) A site like this : http://www.pontiacpower.org/headsearch.htm can show you the plethora of Pontiac heads that are available. A quick-and-dirty search shows "091" 389 heads have a CR of 8.6:1. It might be better to start with that head and shave it a little to raise the CR as compared to trying to reduce what you have. If you pick a shop to do the engine work that knows something about Pontiac engines, they would surely be able to give you the best options.

You're probably going to want to take a look at a few Pontiac-specific sites to get ideas of what can be done vs. what you want to do with your engine. Pontiac Years has a forum that should be a good source of information. Here's a thread on 389 camshaft selection that popped up doing a quick search : http://216.178.81.108/forums/showthread.php?t=455167 . You should also be able to find people with experience changing intakes, too. Fortunately, aftermarket manufacturers like Edelbrock make similar manifolds for both Chevy and Pontiac engines. Intake manifolds like the Performer and Torker series are produced for both engines. Figure out which manifold design is going to fit your needs (i.e. do you prefer low, mid or high RPM performance) and go. I think they even manufacture an MPFI-ready manifold for Pontiac engines if you wanted.

Good luck with your project!

 

Hey guys!
I've found a machine shop that does pontiacs.
These guys seem to really know what's up, so that's a relief.

Anyway, I'm going to be doing this step by step to ease the strain on the wallet, before I send the block in, I want to do all of the extras that I'd be charged for. Freeze plugs, that sort of thing.

Well, I know there are freeze plugs that need to be removed. Camshaft bearings? There's got to be more. Does anyone have a reccomendation for a book, or a website that can kinda guide me through these steps?

It seems kinda rediculous to spend an extra $20 on something that I could possibly do myself.

If anyone's in the detroit-metro area, the shop I'm using is Dynamic Automotive II, Inc. They're over on Wayne Road, south of Cherry Hill

 

The freeze plugs are easy to remove hit the lip of them with a punch and knock them sideways, grab them with some vise grips or pliers and pull them out. As far as cam bearings go i would suggest to a novice engine builder to have the machine shop remove and install them, because they will do them right. Cam bearings can be a real pain in the a_ _. Good luck and keep us posted.

 

dude just saw this...THAT IS AWESOME...I had a 455 ia 73 firebird i had (I traded that car for my rs..it just need too much body work...but anyway..you need to contact Jim Butlers performance pontiac...they are strictly pontiac and they are the way to go because alot of people think "oh its a gm its all the same"BELIEVE ME its not Pontiac engines are a whole different beast from a chevy small block...by the way pontiac never made a small or a big block.They were all big and every part will interchange from a 350 pontiac engine to a 455 pontiac engine..nothing will interchange from a chevy engine to a pontiac.try to find some heads with a 6X or a 4X stamped on them those are the best ones to use on a budget..or you could go all out and get some Ram Air IV heads the best of all...but be warned that a pontiac engine will blow $2000 quick and finding someone to work on them that know what they are doing will be even harder...I learned that too...I am a true believer in the Pontiac engine..and i believe if it is a pontiac car it needs a pontiac engine in it...I think I have a three deuce intake off a GTO around if i can find it I'll let you know...but anyway thats my two cents what ever its worth..congradulations and good luck man....dave

 

I've had cars with 389's 400's a 421 and a 455. my 421 was in a 2+2 1965 and was the 3 dueces set up and the only one that ran good with it. I tried the 3-2's on a 400 in my 69 GP and didn't have much luck with the drivability and the 650 holley vac. secondary out performed the 3-2's. I'm not sure what the 3-2's came off of but I got the intake and all for 50 bucks in 1979 and rebuilt all the carbs and was having to reset the floats about once a month. I think now I might have had it jeted wrong because I never changed them when I bought it.
If I were you, get the heads done (hard seats) magna-fluxed, all new bearings, install a cam as close to the factory spec's as you can. Put a new oil pump on (factory stock) you only need 10 lbs per 1,000 rpm for pontiac. If you use the same pistons, look close on the piston skirt's for any hairline cracks and by all means, use new rod bolts.
From what I saw in your pic's there's a lot of oil sludge build-up in the lifter galley so the previous owner probably didn't change the oil alot or the rings were worn pretty bad so you can count on getting the crank turned also. Pontiac engines are all about torque with their long stroke and pull good to 4,500 rpm that's about all you should need in your firebird. 3:08 to 3:23's would work good on the street. if you put a shift kit or after market trans in, your going to have to beef up the rear or find a stronger one than what's in there now. If you keep it under 5,000 rpm you can get away with pressed in studs on your heads if it doesn't have threaded one's in there already. You might want to check into a set of 3 tube headders too if you can still find them. I think their a little cheaper and their easier to work around when changing plugs and still perform well over stock manifolds.
Oh, and when you get the cam and lifters make sure the lifters are PONTIAC not chevy, there's a difference in the oil groove height. The factory lifters are also self adjusting hydralic and the rockers are tightened down to a torque specification I can't remember. I think it was 35-45 lbs or something like that.
Was the engine together when you bought it? or a basket case?and how long has it been sitting? If it was still assembled and sat a long time your valve springs might have lost some tension on the valves that were open for a long period .

 

TDWillis, SqzBox - Thanks a lot for the posts! We're sending the block off monday, I'm going to build it from the bottom up.

Does anyone know if I can rent a bead blaster or some type of media blaster for cleaning things up? I'd like re-use those valve covers, but they didn't clean up to well. Seems they were chromed or something, and most of it have flaked off, and there is some left. I'd want to blast them down, and paint them. Also, while the bird is out of commission I want to clean up some rust that's forming underneath. Believe it or not, for a Michigan car, that has been a year round car, it's not too bad under there.

DWillis, if you happen to cross that intake, let me know, but don't go looking for it because I'd rather not have to buy three carbs, when I could get just one for the same (or better) performance.

Sqzbox, Nice to read your post. My main goal with the car is reliability. Second is safety, and third is performance. I'd love to street race with it a couple of times just to mess with some little kids in their cars mommy and daddy bought for them. But that's not the priority. The engine was not assembled when I bought it. It was taken apart, and the crank was slipped back in for storage, the heads just barely bolted on (finger tight) same with the valve covers, the intake, and the backwards carb. The rest of the stuff were in the boxes, and trays that they're still in.
Pistons are safe to steam clean, right? I don't know why I ask, I know they are...
Wouldn't they do something about my valve springs when they change the valve seats? The price quote included a valve job, so I'll make sure they intend to fix everything.

Thanks for the advice about the lifters!

 

The tranny isn't a big deal. If you have a good existing TH700R4, buy an adapter plate. If not, start looking for a TH2004R in the junkyards...they put dual pattern ones behind many G-bodies in the 80s, and they are not hard to find at all. If you just want a TH350 or TH400, BOP ones are practically free in most yards, and there are dual pattern ones out there as well (I always go dual pattern if possible, since I work on Chevies and BOP-C stuff too). I'm putting a T56 behind my 455, which is a little tougher ($$$) but very doable.

For parts, I'd reccomend picking up a copy of High Performance Pontiac Magazine; there are plenty of Pontiac-specific parts vendors (Jim Butler Performance, Kaufmann Racing, etc) who can steer you in the right direction when selecting parts. The general mail order places have some parts for Pontiacs, but you won't get decent Pontiac engine advice or help selecting parts from them. Summit won't have a lot of the little things you'll need for that engine, either.

 

 

Since it's still not too late...

What do you guys think about nitrous?

I'm kind of attracted to the idea. It seems pretty neat. If I don't want to use it, it's not on, and the motor is running like it doesn't exist. Then, when it's time for a bit of a boost, turn on the bottle! This way I can get the reliability I want from my engine, and a bit of fun if I go the track or something.

I wouldn't have to with a rediculously low compression ratio like an Super/Turbocharger, so I would still get decent power without it.

Seems like a win/win situation, right??

Opinions desired!

-Chris

(P.S. Shop hasn't called back about the condition of the block yet.)

 

can't you use a BOP adaptor plate?

 

If I remember right most all pontiac v8 blocks where about the same excluding the bastard child that isn't even worth mentioning but I will just cause I like to stir the evil pot.


dun dun dun

the mighty 301 I think was the only one with a different block

 

rx7, you are correct. However, the only difference between a 301 "block" and all other pontiac blocks is the deck height reduction of an inch. The rest of the block's dimensions are the same. So, whatever applies to non-301 blocks regarding engine mounts and transmission adapters will apply to the 301. (Acutally, there are a number of other ways the 301 is different that might require different fabrication compared to the rest of the pontiac family. But, this thread is about 389's..... )

 

just curious since you have an 81 tta how fast would you say it ran the 1/4 stock?
have you done any work to it?
I know it's not a 389 but Im curious


all I remember is my friends N/A 301 and it sucked.
no need for a rev limiter though with the crappy heads/cam. first gear floor it and you couldn't go much past 4300rpms.

 

the best thing about the 301 was the 301 turbo that pontiac introduced...and it was only cool because it had a turbo..i like the 400's and the 455's those two were the most popular and the best(factory) performance engines ever built...they are just so dang EXPENSIVE to build....I have had several t/a's from 73 to 81 and my fav-o-rite one of all was my gold 77 half hurst t-top,muncie 4-speed,400 pontiac engine....someone needs to beat my A$$ for selling it...but you will enjoy your 389 just as well especially in a third gen....keep us posted