1970 455 pontiac engine

[chanan]

Good day members,

I have a 1970 455 pontiac engine that I would like an idea of the value. The engine is complete with all accessories,carb,dist, etc. and is turns freely.

Any info will be appreciated.

Thank you

[avgwarhawk]

How many miles?

[1912Staver]

The value of 455,s is very dependant on which version the particular engine is. There are several diferent head castings used along with other parts. The value can range from not a lot more than scrap for the base model engine, to very valuble indeed for the top hi performance version. You need to dig deeper and find out exactly what you have before anyone can sugest a value.

All the best Greg

[Guest]

Any 455 in good condition even the base 360hp with the small valve # 15 heads & 10.0 to one compression is most certainly not scrap. The higher horsepower and larger valve heads are more desirable, but in any case won't work with today's wizz bang gas. If you want to drive with Today's gas you either have to use dished pistons or change to another head like the 400's 7K3 to get the compression in the nines to prevent detonation. any 455 block in good condition is a welcome addition.

D.

[avgwarhawk]

Any 455 in good condition even the base 360hp with the small valve # 15 heads & 10.0 to one compression is most certainly not scrap. The higher horsepower and larger valve heads are more desirable, but in any case won't work with today's wizz bang gas. If you want to drive with Today's gas you either have to use dished pistons or change to another head like the 400's 7K3 to get the compression in the nines to prevent detonation. any 455 block in good condition is a welcome addition.

D.

Can't a additive be used to boost octane?

[Guest]

Can't a additive be used to boost octane?

_________________________________________________________

Sure, if you can find something that really works. Before I put 7K3 heads on my 455 in 1992, I had to use five gallons of 100 octane fuel to fifteen gallons of 92 pump gas to prevent detonation....that can get expensive, but less expensive than the additives that are in the auto parts store which don't work. When I installed the big valve 7K3 heads ( 400" heads with 96 cc chambers) it eliminated 95% of the detonation. I still get some detonation (the other 5%) on very hot days and low humidity at wide open throttle. those heads decreased my compression to 9.5 to one. The other remedy would be to go with aftermarket aluminum Pontiac design heads from Edelbrock, Wenzler, or kauffman. With aluminum heads you can run about a point and a half higher compression than you could with iron without fear of detonation----that's one of the reasons all new cars have aluminum besides the weight reduction. I might add that everything for the Pontiac engine including Iron and aluminum blocks, heads, cast and forged steel cranks---everything internal is being made in aftermarket and all parts interchange with original Pontiac components.

D.

[NTX5467]

_________________________________________________________

With aluminum heads you can run about a point and a half higher compression than you could with iron without fear of detonation----that's one of the reasons all new cars have aluminum besides the weight reduction. .

D.

Back in 1986, when the Corvette factory aluminum heads came out, I bought a set for my "in process" 350 +.030 engine. I picked the '71 350 pistons to go with the smaller chamber volume of the Corvette heads. I figured it made about 9.5 to 1 compression ratio. I was hoping that I could get away from using super unleaded too, for the same reason mentioned . . . but it didn't work that way. I was using a Cam Dynamics Energizer 266 cam (210 degrees @ .050, .440 lift), for the record. After we got the engine installed, I first put some miles on it beforre I started tweaking the ignition timing and such. With the igniton's base timing set at 10 degrees BTDC, it needed 93 pump octane super unleaded to be quiet. Even a 50-50 mix with mid-grade resulted in trace rattle under hard part throttle. When I tried straight mid-grade, just a few pump octane number less, it rattled worse! So, the theory of being able to buy gas for a 8.5 to 1 compression ratio, yet with a figured 9.5 to 1 cr on aluminum heads, just didn't work that way for me.

Almost all later model engines do usually have aluminum cylinder heads. Weight is certainly a consideration, as machining ease might be another. But I suspect the real reason might be that aluminum heats up quicker than cast iron on a cold start . . . thereby reducing possible hydrocarbon emissions during the cold start testing cycle. I know that I got hot heater water on my Camaro a good bit sooner with the aluminum heads compared to the prior cast iron heads.

One reason that turbos had a temporary disappearance from the marketplace was that the turbo was a big "heat sink", which affected the engine's capabilities of passing the cold start emissions test cycle, which tended to delay getting the catalytic converter to get up to its fully-functional operating temperature. One reason that 4 valve/cylinder heads and superchargers suddenly came to prominence. When the cost of the heated oxygen sensors became more reasonable or "coverable" by engine option costs, the turbos reappeared.

These were just my own experiences. No more, no less. Perhaps others might have had different experiences?

Regards,

NTX5467

Edited March 27, 2012 by NTX5467 (see edit history)

[1912Staver]

Sorry Helfen , I diden't mean to say a 455 is suitable for scrap, however the value of a base 455 core engine is not very high. They can be at times dificult to come by, but with patience they appear at quite a reasonable cost. When I have needed a big GM core engine I look for a good running full size car. I then harvest the engine and sell off what little I can of the rest of the car. Unfortunately there is little demand for parts from these cars so I have little choice than to scrap them. The up side is with scrap price as high as it is the core engine ends up being almost free. This works well for Mopar 440's, Ford 429's/460's GM 400, 454, 455. etc. Most of these engines went into full sized cars, pickups and motorhomes. Now that they have outlived their first life it is good they can go on to a new life in a muscle car.

Most people around here just take these vehicles complete to the crusher. I think this is a crime when good core engines are involved.

Greg in Canada

Edited March 28, 2012 by 1912Staver (see edit history)

[chanan]

Thank all for the input. Block and head numbers will be posted tomorrow. Sorry don't have a clue on the miles. I've had the engine for some time now and I'm trying to scale down on projects.

This, along with a 67 GTO project will give me more room to finish other projects.

[chanan]

Back to the 1970 455.

The engine code is 0521182 YH front of block and 9799140 on the rear of block.

Head numbers need to be cleaned up in order to get a good reading.

Thanks

Robert

[Guest]

Back to the 1970 455.

The engine code is 0521182 YH front of block and 9799140 on the rear of block.

Head numbers need to be cleaned up in order to get a good reading.

Thanks

Robert

_________________________________________________________

The 1970 455 YH block is the 360 HP with 10.0 compression small valve 1.96/1.66 with a head cast of #15 on the top of # 3 and 5 exhaust port on the left side of the engine, and on the rt. side on top of the exhaust port of # 4 & 6. this engine comes with the 067 camshaft. Also, these later open chamber heads including the 350 engine still have bigger intake valves ( 1.96 ) than the early Super Duty big valve Heads ( 1.92) for the 389 in 60-62.

The 421 Super duty has smaller valves ( 2.02 / 1.76 ) than the high performance 350, 400, 428, and 455 high performance engines which are 2.11 / 1.77.

Just a interesting note, the 350 Pontiac engine is really a 355, the 428 engine is really a 427, and the 455 is really a 456.

The original 1963 326 engine is really a 336. In 1964 it becomes a 326.

D.

[chanan]

Thanks again for the response.. Were these differences during the DeLorean, Estes and Knudsen years when they were trying to slip things past headquarters? Do you have a idea on the value.

As I said before the engine is completely trimmed and free. I have a young man paying his dues as an engine builder and I want to be fair with him and myself on the price.

Thanks again,

Robert

[Guest]

Thanks again for the response.. Were these differences during the DeLorean, Estes and Knudsen years when they were trying to slip things past headquarters? Do you have a idea on the value.

As I said before the engine is completely trimmed and free. I have a young man paying his dues as an engine builder and I want to be fair with him and myself on the price.

Thanks again,

Robert

_______________________________________________________________

Robert, I also have a complete 455 Pontiac that I have kept as a extra, it came from a good running but trashed body 71 Bonneville. Just me saying now, I wouldn't let that engine go for under five hundred...that's just a rebuildable engine were talking about and the heads on it have too large of chamber volume to be of any use to me.

The engine differences under leadership vary. The 326 was most likely under the guidance of Knudsen, but Knudsen was promoted from Pontiac to Chevy in the fall of 61, but the design of the 63 cars were partially under his watch. My guess is that Pontiac was unaware that there was going to be a engine size cap for the newly introduced intermediates for 1964. When that edict came out Pontiac had to make the 336 a true 326. The limit for those cars was 330 cu. inches.

As far as the 428 goes, after the GM ban on racing in 1963 I think Pontiac thought someday it might be lifted so they could race again, and at that time NASCAR, NHRA, IHRA, had cubic inch limitations of 427 inches... that is why I think the 428 Pontiac is a 427. The other two engines 350 & 455 were named that way possibly because it was a nice round number.

If you want/ need more information like; why did the 389 become the 400 and why did the 421 become the 428? just ask.

D.

[chanan]

Thanks once again for the info. I'll be back in general discussion on some other items.

Robert

[Guest bills999]

I have found a 1970 Pontiac ambulance with a 455 engine is there any thing

special about this engine??

Should I get it? the overall condition of the ambulance is poor to awful.

I am thinking of salvaging the power train.

Is this a worthwhile endeavor.

Thanks in advance.

bill

[Guest]

I have found a 1970 Pontiac ambulance with a 455 engine is there any thing

special about this engine??

Should I get it? the overall condition of the ambulance is poor to awful.

I am thinking of salvaging the power train.

Is this a worthwhile endeavor.

Thanks in advance.

bill

YES!

[Guest bills999]

Not to be glib but why?

[Guest bills999]

I feel i must add i don't have enough room to adopt all the cool things

i find.

[poci1957]

IMO the 1970 455 is the pick of the litter among regular production Pontiac V8s. For anyone building a Pontiac street machine this engine is a great find, if it were in my area I would pay at least $500 for a complete rebuildable one. Just one man's opinion but the comments above seem to agree, Todd C

[Guest]

IMO the 1970 455 is the pick of the litter among regular production Pontiac V8s. For anyone building a Pontiac street machine this engine is a great find, if it were in my area I would pay at least $500 for a complete rebuildable one. Just one man's opinion but the comments above seem to agree, Todd C

I agree with Todd, and with each year fewer and fewer remain. Also latch on to that long tail shaft T-400 too! Guess what, if that car has rare disc brakes option that I believe are only 69-70. 1971 up to 76 are different. So grab the brakes, and front spindles--those two go together and can be used on early cars. My 62 Catalina has those brakes and with the tall spindles and fitted to the early cars you get the bonus of negative roll steering which really wakes those cars up in the handling department and they don't wear tires out as fast either.

D.

[PONTIAC1953]

the 1970 455 is the only year high compression 455, in a full size pontiac, the 4bbl horsepower was a stock 360 horses, in a gto, it was 370 horses. the motor is worth it's weight in gold. don't pass it up. charles coker, 1953 pontiac tech advisor.

[Guest bills999]

Thanks for the info.

I guess it's time to talk to the owner.

BTW this car is in so. cal. near San Diego if some one else would be interested I could put you in contact with the owner.

bill

Edited June 14, 2012 by bills999 (see edit history)

[Guest]

Thanks for the info.

I guess it's time to talk to the owner.

BTW this car is in so. cal. near San Diego if some one else would be interested I could put you in contact with the owner.

bill

Bill, if you don't really want the car or it's contents I think you should contact the people of the San Diego or Southern California chapters of POCI. It's important that either the whole car or it's parts are saved.

Don

[Guest]

Thanks for the info.

I guess it's time to talk to the owner.

BTW this car is in so. cal. near San Diego if some one else would be interested I could put you in contact with the owner.

bill

Bill, if you don't really want the car or it's contents I think you should contact the people of the San Diego or Southern California chapters of POCI. It's important that either the whole car or it's parts are saved. If you want PM me and I can put you contact with a friend of mine who is president of POCI.

Don

[Guest bills999]

I probably would not get around to doing anything with it.

PM sent.

[Guest 70GTO455Convt]

Back to the 1970 455.

The engine code is 0521182 YH front of block and 9799140 on the rear of block.

Head numbers need to be cleaned up in order to get a good reading.

Thanks

Robert

Hi Chanan,

Do you still have the 455? I'm interested in buying it if you do. You can call me at 253-576-9068. Also, I'm wondering if the YH is actually a YA. 9799140 is the casting number for a 1970 455 but I believe the two letter code should either be YA (auto trans.) or WA (manual trans.).

Thanks,

John

GTO Engine Codes!

1970 Pontiac GTO Production Figures and Specifications

[PoPP]

My first car in the 80s was a '70 Bonneville with the 455.  Yep, it took premium leaded gas.  I remember it as having really good power, a great 2-lane highway passer.  Completely uncool though for a teenager.  It had been the family car before it descended to me, and my parents didn't make use of the power that thing had.  Ah the things you don't appreciate until they are long gone.  I sold it after a year or two for $195 to a single working mom, I believe.  It had near 200k on it.  I saw it later at a pizza shop or somewhere, where she was working, and the odometer had rolled over.

 

One of my vehicles now is a Chevrolet Caprice from the '90s that I bought for the engine but that ended up being too nice to scrap.  It's a nice driving, comfortable car, but the 5.0L power doesn't touch the Pontiac, or the big 350-powered Chevys I got to drive in my youth.  ...Sigh, lol.

[cheezestaak2000]

since most le mans coupes have become mysteriously GTO'S, i'd think there would be a good market for that 455

[padgett]

Hate to rain but the '70 455 was a warranty disaster, lost oil pressure and cranks right and left. Most was corrected in the '71 but the 455HO was a hard sell in '71 and '72 even though very good engines.

BTW 70 455 head should be a 64.

 

ps you realize this began in 2012 ?

[Frank DuVal]

PoPP you need a 94 to 96 Caprice with the LT-1 engine!😉

[Pfeil]

14 hours ago, padgett said:

Hate to rain but the '70 455 was a warranty disaster, lost oil pressure and cranks right and left. Most was corrected in the '71 but the 455HO was a hard sell in '71 and '72 even though very good engines.

BTW 70 455 head should be a 64.

 

ps you realize this began in 2012 ?

 

 

 The 70 455 has either # 15 or 64 heads, # 64 are big valve heads at 87cc. Neither head will work very well on todays fuel. It's best to use a aftermarket aluminum head or reduce your compression by using a factory 400" Pontiac Iron head like a 1971 # 96, or 1972 7K3, both at 96 cc's.

 Don't worry if you have a seasoned 1970 block as they are time tested after all these years and are just fine. I've beat on mine for 27 years drag racing and road racing no problem.   

[padgett]

7K3 only has three manifold bolts and wasn't hardened. 6X has 6 bolts and hardened seats.

[Pfeil]

48 minutes ago, padgett said:

7K3 only has three manifold bolts and wasn't hardened. 6X has 6 bolts and hardened seats.

 

Not known to everyone, every Pontiac V-8 head is hardened from 1971 but not always factory stated---G.M. knew what was coming.

 7K3 heads have "4" manifold bolt holes and  bosses for drilling and machining for the other two, which most guys into performance using RA3 manifolds or headers drill and tap.

 6X heads won't work as well as # 7K3 or # 64 because even the 6X 400 heads only have 101CC which are too low compression. You would be better with 4X heads off a 400 at 98cc. 

Edited January 12, 2020 by Pfeil (see edit history)

[PoPP]

21 hours ago, Frank DuVal said:

PoPP you need a 94 to 96 Caprice with the LT-1 engine!😉

Oh, I know!  The nice ones left are outta my price range.  I'll keep looking.  There's a beauty for sale now with 35kmiles - $9,900.  I looked at one a couple months ago for $2,700.  It ran really well, but overall wasn't as nice as I'd hoped.

 

I locked the keys in my '89 RS Camaro (L03, throttle body injected 5.0L) when I was in the air force in the 90s, and a local cop gave me a ride back to the dorm for my spare set, in his 9C1 Caprice.  My car looked really good and fast and he gave me a little demo of the Caprice, kinda wondering how he'd stack up if he had to chase one.  There woulda been no contest.  That was a fast car.  My Camaro was decent, but had highway gearing and was not an exceptionally powerful car.

 

The L03 with 2.56:1 is what my Caprice has.  They weren't even on my radar, and I just sorta happened on to it.  Couchmobile.

[PoPP]

22 hours ago, padgett said:

Hate to rain but the '70 455 was a warranty disaster, lost oil pressure and cranks right and left. Most was corrected in the '71 but the 455HO was a hard sell in '71 and '72 even though very good engines.

BTW 70 455 head should be a 64.

 

ps you realize this began in 2012 ?

I don't know the mileage that was on ours when we got it, or if it had any major work done before.  I'm thinking an older couple had it before us.  I have a vague memory of something about it getting the lifters done or something when I was a kid.  It was in our family for 8 or 10 years, and like I said, had nearly 200k on it when I sold it, but it didn't get hot rodded or the like.

 

I think it was fouling the #7 plug when I sold it, and had lost the carb secondaries for some reason (prob. something simple).

 

The car had a little Indian head shape as the brights indicator on the instrument cluster (Pontiac, or Bonneville, I guess).  And the transmission had Low, "Super", and Drive.  Marketing stuff...

[Pfeil]

27 minutes ago, PoPP said:

I don't know the mileage that was on ours when we got it, or if it had any major work done before.  I'm thinking an older couple had it before us.  I have a vague memory of something about it getting the lifters done or something when I was a kid.  It was in our family for 8 or 10 years, and like I said, had nearly 200k on it when I sold it, but it didn't get hot rodded or the like.

 

I think it was fouling the #7 plug when I sold it, and had lost the carb secondaries for some reason (prob. something simple).

 

The car had a little Indian head shape as the brights indicator on the instrument cluster (Pontiac, or Bonneville, I guess).  And the transmission had Low, "Super", and Drive.  Marketing stuff...

 

200K is certainly a seasoned block, Lifter problem is unusual, however the biggest problem to all GM engines and some Ford engines with timing chains was the nylon coated timing gear sprocket on the camshaft which usually worn out between 30,000 and 75,000 miles. Some last longer, some shorter and the engines subjected to a lot of heat or overheating go the fastest.

 In the fall 1956 Pontiac's general manager Bunkie Knudsen set out to change Pontiac's image. Knudsen in a interview with High Performance magazine considered the Indian race a dead race and he didn't really want Pontiac associated with it. The new  brand image would be the spear or arrow head. The first thing to happen was the removal of Pontiac's Silver Streaks from the hood and rear deck area. Once that was accomplished on the 57 models Knudsen set out to get rid of the Pontiac mascot- Indian head, however for G.M. patent regulations it required Pontiac to have that image on the car some place, that someplace was the high beam indicator light on the speedometer.

As far as the shift quadrant goes on a 1970 Pontiac we are talking about a very understandable indicator meaning (P)park, (R)reverse  (N)neutral, (D)drive, (S)second, and (L)low ( as in first ). Nothing mysterious here!

Old= 

New=

Edited January 13, 2020 by Pfeil (see edit history)

[PoPP]

12 minutes ago, Pfeil said:

 

200K is certainly a seasoned block, Lifter problem is unusual, however the biggest problem to all GM engines and some Ford engines with timing chains was the nylon coated timing gear sprocket on the camshaft which usually worn out between 30,000 and 75,000 miles. Some last longer, some shorter and the engines subjected to a lot of heat or overheating go the fastest.

 In the fall 1956 Pontiac's general manager Bunkie Knudsen set out to change Pontiac's image. Knudsen in a interview with High Performance magazine considered the Indian race a dead race and he didn't really want Pontiac associated with it.  The first thing to happen was the removal of Pontiac's Silver Streaks from the hood and rear deck area. Once that was accomplished on the 57 models Knudsen set out to get rid of the Pontiac mascot- Indian head, however for G.M. patent regulations it required Pontiac to have that image on the car some place, that someplace was the high beam indicator light on the speedometer.

As far as the shift quadrant goes on a 1970 Pontiac we are talking about a very understandable indicator meaning Park, Neutral, Drive, Second, and Low ( as in first ). Nothing mysterious here!  

 

That is interesting.  I had a '69 Impala with the 350 that had some small plastic chunks come out in an oil change.  I suppose that's what it was.  I dated a guy's daughter briefly, who was a real good mechanic (the guy, lol), and he rebuilt the carb for me and changed the timing gear and chain also.  He knew really what he was doing, and that car seemed to be as fast as my Bombeville was.  Less horsepower, but probably somewhat lighter.

 

On that shift indicator stuff, it was the only car I remember having that called second gear (or "L2" as some of them had it), "Super".  It was in the owner's manual.  Seemed kinda gimmicky to me.

Edited January 13, 2020 by PoPP (see edit history)

[Pfeil]

14 hours ago, PoPP said:

 

That is interesting.  I had a '69 Impala with the 350 that had some small plastic chunks come out in an oil change.  I suppose that's what it was.  I dated a guy's daughter briefly, who was a real good mechanic (the guy, lol), and he rebuilt the carb for me and changed the timing gear and chain also.  He knew really what he was doing, and that car seemed to be as fast as my Bombeville was.  Less horsepower, but probably somewhat lighter.

 

On that shift indicator stuff, it was the only car I remember having that called second gear (or "L2" as some of them had it), "Super".  It was in the owner's manual.  Seemed kinda gimmicky to me.

Oldsmobile did call the "S" super.

"Only" in the year 1964 on full size Pontiac with Roto or Super HydraMatic did you get a "S". Previous years on the 3 speed four range Roto and the 4 speed Super HydraMatic you got (P)park, (N)neutral, (D) Drive left (fourt gear or forth range) (D)Drive right ( 3rd range or 3rd gear) and (L) Low (first and 2nd range or 1st gear and 2nd gear).  The Drive position looked like ^D^ for left or rt which see above for explanation.

After 1964 all full size Pontiac became P,N,R,D,S,L

 

  

Edited January 13, 2020 by Pfeil (see edit history)

[Pfeil]

27 minutes ago, PoPP said:

 

That is interesting.  I had a '69 Impala with the 350 that had some small plastic chunks come out in an oil change.  I suppose that's what it was.  I dated a guy's daughter briefly, who was a real good mechanic (the guy, lol), and he rebuilt the carb for me and changed the timing gear and chain also.  He knew really what he was doing, and that car seemed to be as fast as my Bombeville was.  Less horsepower, but probably somewhat lighter.

 

On that shift indicator stuff, it was the only car I remember having that called second gear (or "L2" as some of them had it), "Super".  It was in the owner's manual.  Seemed kinda gimmicky to me.

Just a FYI, a 69 Impala is about 500Lbs lighter than a 1970 Bonneville, However a 350 SBC make about make less than 375 Ft. Lb. of torque and a 1970 Bonneville 455 with 360 HP makes 500Ft. Lbs. of torque. Given both vehicles in new pristine condition the Bonneville would blow the Chevy away.

[padgett]

In 1972 4bbl Pontiac engines got steel gears. BTW in '70 Pontiac HP rwatings were pure maketting. The same engine would have different HP rating in different Car lines (F, G, A, and B bodies) and in a few cases different engines woud have the same ratings. They also played the "derater the HP so the sans-coulottes will buy the one we want them to buy. (69 Chev 290 vs 295hp, 430 vs 435 hp...)

 

BTW Pontiac kept the indian head high beam indicator for the lawyers: said it was needed to maintain the trademark.