Hot Rods Lets see some Pontiac Motors in your Hot Rod

Some cool pics.

 

455HO Tri-Power in my '64 Goat

 

model A modified 73 400/400 project. currently worken on the floor and steering so i can hit the bodywork and get it painted in the new year

 

Ya can't use 670's on pump gas. You'll either need a custom dished piston or a minimum of 98 octane 100% of the time.

Bruce

 

Hairy Cherry '51 Henry J with '74 Pontiac 350

 

cool thread, I'm looking to put a pontiac motor in a T bucket that I have.

 

Axles is my favorite 32' of all time I like the proportions of it, and a pontiac makes it even better.

 

thats been my understanding, so far all i know is the block numbers are 66 389 and the 670 heads are 67 400

its got speed parts on the outside and you can tell it was a running motor, so when i get a chance i am going to tear it down and see what the builder did, I am wondering if it was bored out an ran with 400 internals or if its maybe got trick forged pistons... as soon as i break the seal i will post pictures

 

You guy's are making this thread happen. Lot's of info, keep the stuff coming!

 

An engine builder with a bit of Pontiac knowledge knows they can put a STD bore 400 in a 389 so the 67 and later heads valve angle won't crash into the piston, which it would if you used a 389 piston. A .060 389 is a STD bore 400.

 

ok this thread came back to life and it got me curious "what is inside this mystery motor"

this is what I knew, block 389 heads 400 (670), dual 4 offy 360 intake, dual predetor carbs (gone) mallory ignition....

I opened it up and found that it wasnt sealed up very well while in the rain, the 2 cyl that had the intake valve open had some water and gunk
but it cleaned up ok with some carb cleaner


**** QUESTION:
What are these pistons, i have never had a pontiac motor and dont know jack shit about them. From what the pictures show what can you guys tell me...

 

few more pictures ... NOTE the upsidedown 40 with an arrow pointed to the front of the motor

 

Those are 389 pistons. And coupled with the 670 head you can easily be in trouble with detonation, plus, if the cam has more than 400 lift the valves could hit the pistons. The upside down arrow is in the correct position because it's pointing forward.

Can you measre the bore? You can easily swap heads to a lower Cr. set, which will do two things, one is the obvious, lowers the Cr., Two, because of ther larger chamber and shorter valves you can run more cam lift with no problems.

Designing cams for low Cr engines is one of my fortes. Tuning a low Cr is a trick. You won't find that info anywhere. No books. Zippo. I made low compression engines my main study when I went to Chaffey college and took their Advance Engine design course in 1990/91.

My first experiment turned the Pontiac world upside down and caused many problems with small minded dudes. I built a 9.2 Cr 400 and put it in my 65 GTO. I was hoping for low elevens. On it's first pass at Carlsbad it went 10.72 at 123 mph.

I learned a lot, and instead of learning how it's done, about 50% of the Pontiac community thought I was lying. Mainly because some OLD Pontiac "guru" told them I must be lying cause he'd never seen anything like that and he didn't "think" it was possible. That was 1993.

Occasionally one of these doubters like to pop up and inform everyone I'm the devil.

Ha!

f' em.

I won Indy.

 

Not my hot rod, but it has pontiac moters.

 

On the motor above I just noticed someone did you a favor by using a later timing cover and balancer. Which takes what we call the eleven bolt water pump. (Count all of the mounting holes.) Earlier units have a small p.o.s. balancer and an 8 bolt water pump.

All of the later stuff in easier replaced.

 

Tring to save one of the old ones 60- 389 .060 274/284 9.5cr I hope, M20 3.42 getting close. The 1/4" extension is for pulley align ,just lay it in water pump pulley V and turn gen alt or any pulley,no monkey businness works well,aah, you guys probley know that already.

 

my caliper is at work but monday i will bring it home..

since the 670 heads are such good heads shouldn't i make my changes in the bottom end? especially to save money since thats not something i have much of. I want good power but right now im not going for huge numbers I just want something with "some git" that is reliable till i can put more money into it.

 

Probably so. If you are looking for a budget piston sealed power make a cast piston that will work for you. The part number is 411NP.

They are commonly called an 8 eyebrow piston as the have 8 valve notches so that they will work with the 389 or 400 heads. IIRC you will loose about 12-13 cc's volume with this piston which in your case will be to your advantage with the 670 heads.

HTH

 

this a 400 in my 56 F100, runs great and has tons of torque

 

670's are nothing special. In fact, that closed chamber design was quickly dropped, lasting one year only. The open chamber heads breath much better. Here's a fact - all D-port factory Pontiac with screw-in rocker studs and the large 2.11 intake will all flow within five CFM of each other. They will also respond the same to port modifications. The main difference is in the size of the combustion chamber.

What I do for guys who want to keep a certain old high compression head like yours, for whatever reason, I design a custom dished piston that takes care of the problem. Kieth Black claims their off the shelf hyperutectic dished pistons work, they don't, The dish is not big enough to lower the Cr for 92 octane on a head with a nominal combustion chamber size of 72 cc's.

If you're interested in the right pistons PM me. Regards,
Bruce

 

Hey Bruce...
How'n hell are ya? Listen up, this is the guy from Maine with the 455 powered 31 Ford. I chew'd you ear off hmm.. musta been late 80s or so. Me,another guy and son met up with ya at Maple Grove for a Pontiac event you put on.
Anyway,, you sent me specs and pics of a home-made type tunnel ram for my old "blister". Well we made it! Works great.
Pontiac Slim

 

Hi Slim! Remember you? Every time someone comes into my office they see that big picture taped to one of my cabinets of your coupe doing a burnout with your pal holding on to the roof keeping it in the water. Very cool. Great to see you still have the car. Good to hear from you!

Bruce

 

May I ask...Bruce who??
Are you aquainted with R&R Engineering?
Just curious..670's wern't bad heads.
Are you trying to tell me ALL Pontiac D-port flow the same...with in 5cfm...really..?? Asking a question...
FWIW: I used to run my 60 Ventura 425A 348HP on 93 octane....ran well...no pinging. Just be sure cooling system is up to par and run a 160 T-stat..
Anyhew.....Pontaic's are cool...
I notice a lot of "PY'ers" here...

 

Here's my Hot Rod...
It's a 508 CI Pontiac motor with KRE heads and Wenzler T-ram 2X4 intake..
Car run 10.90's @ 125 MPH in good air...weighs in at 4,126 Lbs..
It will click off 6.90's@ 99mph in ther 1/8..

 

Those are just too cool

 

There is no "magic." If in fact you ran an old 10.75 Cr engine on 93 octane there was a mecanical reason is didn't bust the ring lands out if it.

I get this from guys every once and awhile, and it's statements like this that cause other guys to make mistakes designing a combination.

There's an allowable plus and minus tolerance on ever machined part. If in fact all of the factory tolerances added up to make the Cr the lowest it could be, then yes, you may get away with running a low octane it was not designed for. PLUS, as you said, you must keep the water temp very low.

Running a 160 T-stat only means the stat is open all of the time at anything over 160, which is not the wat a stat is designed to operate.
They need to be high enough, (180, 190,) so they can close for a while,letting the water cool in the radiator before opening and dumping a load of cool water into the engine.

In 1960 a 10.75 389 was desinged to run on 98 octane MINIMUM. Back then 93 octane was the cheapest regular.

Of course you get a little band-aid help by running a large cam, but not much because at the point the engine is most efficient. (max torque,) IE: max load on the engine, you better meet the octane requirement the engine must have or mother nature will teach you a lesson.

There are no tricks. I can debunk and clearly explain every myth out there.

Your car is very nice. I had a 60 Ventura project I was hoping to build it until I had to sell it after the accident. You didn't need 508 ionches to run 10.90's, a 455 can do the same thing. But, hey, there's several ways to skin a cat. I just find it more fun using the traditional Pontiac 455 and smaller engines.

When I built that 672 hp Pontiac 350 at 9.5 Cr. many people figured it was fake. I like to meet those doubters on the starting line. !
Bruce

 

\
Bruce...first off..thanks for compliment on my car....and yes I could have run the pi$$ out my 462's(455) and hit 10's..but at what cost and reliability..You know a Pontiac block only takes so much HP and then splits up the middle...no matter what you do..Are you saying my IAII block is not a "traditional" Pontiac...?? It was built by Jack Gaydosh and has nothing but the best in it...short of aluminum rods..If I get suspension to hold power I believe low to mid 10's are possible...even with this 4,100lb.
full size Ventura..
Are you doubting ME about my old 60 425A....there was nothing mechanicly amiss with this car...41,000 mile Cal. car...yes..it had a aftermarket grind (HYD) cam running retarded which should have bled off some cylinder pressures.
I sure as hell know what detonation/pinging is...there was none,nada,zilch..
T-stat..T-sat....160 is 160...how hard is that ??
I was at Kanawa Valley Drag stip in WV at POCI meet and saw your bad 350 run.....what happened to it? It was a nice looking car. Wasn't Andy wrenching then? And yes..I thought your 350 was not a fake..just didn't belive HP claim.Sorry..my opinion. 672 HP out of 350 C.I. = 1.92 HP per C.I....at 9.5 CR I don't believe it..just the way I see things. But hey...I'm no Pontiac God...
Shall we talk about CFM vs VELOCITY... That's a no win topic too...again IMO..
I'm done now....I think...
Note: Never mentioned R&R Engineering ..??

 

I know for a fact, from experience, that a Pontiac block can make 1000 hp and not break. You just have to know what you're doing. Many people do not. Jack Gaydosh is a great guy and I respect him. But if he really believes he can't make reliable 900+ hp power without having problems then he could use some friendly help.

Salesmen that are trying to sell the aftermarket block, which is, um.., aftermarket, not a traditional, or I suppose saying it more clearly, an original block, those people say the stock block will break in order to make sales. And it works for them. People without expeince don't know who to believe. They end up saying things like, "Sounds good to me." Which means, he has no experince but needs to believe someone.

I will help you understand something. Your statement about detonation is incorrect. Just because you never heard it ping doesn't mean it wasn't detonating. As a full time builder for 17 years I've seen the inaudible broken parts. Parts that came from engines guys would bring me to rebuild. I would show them the broken ring lands and broken rings, and pounded rod bearings and they were adament. "What detonation? My engine never made a sound!"

The analogy can be easily understood like this: Let's use a 12 inch ruler as a reference. Let's say audible detonation happens at the eleven inch mark. At the 10.750 mark you still have detonation, it's just not as severe. Audible detonation is extreme and severe. Inaudible detonation will rob power, shorten the engines life, and on two occassions I witnessed it breaking cranks. Of course it will also break ring lands and rings and pound out rod bearings.

Kinda like the Grand Caynon was made from small amounts of water moving across the ground, you're parts will not have a normal life if you do not meet the octane requirement 100% of the time. That's mother nature talking. Not me.

I don't understand your statement of the 160 T-stat.

If you don't believe in my 350 then you're saying that one of the most respected dyno facilities in the world lied about their testing of it. Do you really believe that they would risk their reputation for one person? Hardly.

When you say you don't believe the power numbers because, "That's the way you see it," and "it's your opinion," you're saying you have no scientific facts to refute the evidence. Westech also flipped out when they dyno'd the engine. At the end of that day the owner of Westech came to me and said in a hushed voice asked me, "Bruce, I have to know." and I didn't know what he meant. He said this engine was making power like one of my King Street 455 engines, and if he gave those numbers to Marlan Davis to write the story Marlan would be all over his ass.

Read the story and open your mind. http://www.pontiacengines.com/indexcopy350.htm
See the dyno owner measuring the bore and stroke?

There's a reason why I was able to have the quickest NHRA Super Stocker in history for fours years straight.

By having a college education in Advanced Engine Design and R&D'ing my butt off, and most importantly, having an open mind. Do not listen to the old school retoric about what a traditional, ok, original, Pontiac block can or cannot achieve. You should be proud of my accomplishments and share them. If you wish to question them, then do it with an open mind. No need to get offensive. You know who I am. I don't need to answer your question of my business name. Most everyone likes the name. But it doesn't tell you what I do, so I use the web address more because it gets a person right to the point.

I'm not a God, but evidently I'm the hardest working and luckiest Pontiac engine builder out there. The evidence stands on it's own.

I've got one for you - seeing how you made some comment about wanting to talk about CFM v/s Velocity..............

Do you understand in order to have more velocity you must have a restriction?
So what does a restriction have to do with making more HP?

Good day.

Bruce

 

Ours, 65 GTO, '70 400 bored .30 over. '67 143 heads,Wenzler tunnel ram.

 

Now THAT'S a great lookin' '65. I was going to make mine look like Don Gay's Infinity '65 GTO which is very close to the same color as yours. On the door it would say, "Not Gay."

I mean, I'm not Don Gay, (and I'm not gay,) so all I'm saying is I'm not I'm not Gay.
Then I thought....tooooo complicated for that joke.

Here's mine. Long way to go yet.



I'd like to make it look like the orig Brutus....