72 Blazer Fremont Skunk Works vehicle??

[Dust Bunny Queen]

Hi all. First time post.

6 years ago I bought this blazer, shown in my avatar. 72 K5 CST, from the second owner. The first owner who was a friend of the guy we bought it from told us it was manufactured in the Fremont Ca plant and that the original owner worked at the factory. I was in love with this Blazer and finally wheedled the guy into selling it to me.

SO.....last year we had a cracked manifold and our friend who is a retired GM master mechanic and does shade tree mechanicing ordered the appropriate part manifold before he started work on the engine. However, the bolt pattern didn't match and thinking that the NAPA (No Auto Parts Anytime) guys ordered the wrong thing, took the old manifold in and LO and BEHOLD it is a Corvette engine manifold. And....we have a Corvette engine in our Blazer. Wha????

Getting back to our seller he assures us that neither he or his friend, the original owner who is now deceased, had EVER changed out the engine and that was as it came from the factory. We are going to need to pull the engine to get a good look at the block ID.

BUT....he suggested that perhaps his friend who worked at the factory had the Blazer modified at the assembly line by himself and his friends. Skunk works? We do know that the Blazer runs like a sun of a gun down the freeway and has power to spare. Also my husband thinks that the gear ratio has been altered to 'give it legs'. Now I'm not a mechanic....just a gal who loves her Blazer, and don't know all that much about the technical details. When he gets home from work, I'll ask him to give the details. We did replace the transmission and just recently changed the wheels and rear shocks to level out the look.

How can we tell if the engine was factory installed? I have a photo of the original order sheet.


Here's another shot of the side.



http://i48.photobucket.com/albums/f2...ps3f37ed16.jpg

[Dust Bunny Queen]

Here's a better side view with the old wheel and tires

[briank]

Get a short step ladder and actually crawl in the engine. I used my cell phone and took a bunch of pics and then checked them. The numbers showed up on the pics so you shouldnt have to pull the engine. Nice blazer..... and bennett gas pump

[asolde]

Try and get the numbers off of the front passenger side of the engine stamp pad and also get the casting numbers off of the drivers side very rear of the engine. That will tell you a story when you decode them also you can get the numbers off of the intake manifold and carburator for more information. Even your distributor will have numbers you can decode. Assuming you have a original engine. Heres where you can decode them at http://www.nastyz28.com/sbcmenu.php I am not certain but I believe alot of the parts on our blazer engines are the same as corvette engines.

[Bigdav160]

That's a nice Blazer. I'm a fan of the bronze. My first Suburban was that same color.

Don't believe those past stories. The Corvette engines all came out of Flint and were stamped with numbers as the cars were built in St. Louis.

My Truck has a real Corvette engine also, but it wasn't installed at the factory.

[Dust Bunny Queen]

Thanks for the suggestions and the info!! Nice to find this forum.

We will find the block numbers and the cell phone photo sounds like a real good trick. I thought it odd that the engine would have a corvette manifold. Unfortunately, the old left side manifold is history. My hubby said the position of the outlet not the bolt pattern was the difference. Duh....shows what I know about mechanics. The right manifold is still the original

We won't have much information until next week 'cuz we are off tomorrow to go to Reno for Hot August Nites in our 67 Chevy Stepside.

[Keith Seymore]

Originally Posted by Bigdav160

Don't believe those past stories. The Corvette engines all came out of Flint and were stamped with numbers as the cars were built in St. Louis.

I agree with this.

We have heard stories of Pontiacs being built with "upgraded" engines - but in that case all of the more desireable engines were already in the same vehicle final assembly plant.

A "Corvette" engine would not normally be in a truck assembly plant and would therefore have to be specifically shipped there in order to accomplish this.

Ain't gonna happen (too many people involved in the duplicity).

By the way, I build special vehicles for GM for a living (both in "skunkworks" and down the regular assembly line). Believe me, it's almost impossible to get done even when it's a legitimate vehicle program and everyone on the team is getting paid to make it happen (lol).

K

[Keith Seymore]

Originally Posted by Keith Seymore

I agree with this.

We have heard stories of Pontiacs being built with "upgraded" engines - but in that case all of the more desireable engines were already in the same vehicle final assembly plant.

A "Corvette" engine would not normally be in a truck assembly plant and would therefore have to be specifically shipped there in order to accomplish this.

Ain't gonna happen (too many people involved in the duplicity).

By the way, I build special vehicles for GM for a living. Believe me, it's almost impossible to get done even when it's a legitimate vehicle program (lol).

K

By the way, one of my Pontiac buddies tried this back in the day in the Pontiac Michigan assembly plant. He hand selected the components and built his special engine in the experimental build room.

Imagine his horror as he watched his hopped up special engine go into a station wagon 6 cars ahead of his on the assembly line. He had miscounted, and some random person could probably never figure out why their wagon ran so good.

K

[Dust Bunny Queen]

RE: the Pontiac story....LOL

I guess you just can't believe the stories that the sellers will tell you. I do know that my Blazer still has the original plates from 1972 Gold on Blue.

We put in a 700r4 tranny after we bought it, and the cam and lifters had been changed for better performance by the previous owner. We don't know the specs on THAT unless our mechanic friend wants to dive into it. We do know it runs like a scalded ape on the freeway. I "lurve" my Blazer.

[jaros44sr]

Originally Posted by Keith Seymore

By the way, one of my Pontiac buddies tried this back in the day in the Pontiac Michigan assembly plant. He hand selected the components and built his special engine in the experimental build room.

Imagine his horror as he watched his hopped up special engine go into a station wagon 6 cars ahead of his on the assembly line. He had miscounted, and some random person could probably never figure out why their wagon ran so good.

K

That really sucks wind, but a funny story. Can you imagine a grandmother going to the grocery store in her station wagon, and burning rubber out of the parking lot there goes the eggs and bread...

[Keith Seymore]

Originally Posted by jaros44sr

That really sucks wind, but a funny story. Can you imagine a grandmother going to the grocery store in her station wagon, and burning rubber out of the parking lot there goes the eggs and bread...

Yes - I can.

My mom (all 5' 4" of her) drove all our factory Pontiac race cars on the street, to the grocery store. SD Catalinas, NHRA record holding B/Stock GTOs, etc - because back then you usually only had one car, so it had to do double duty.

However - normally it wasn't a "burn rubber" kind of thing. Usually it was a "car won't start" kind of thing.



She's a grandmother now, of course.

K

[rsavage]

Your Blazer is 4X4 so the original exhaust manifolds are center dumps straight down as were many of the early Corvettes. However, the exhaust outlet on the trucks was 2" while the Vette manifolds were 2 1/2" outlets, if I remember correctly.
Posted via Mobile Device

[DeadheadNM]

According to the VIN shown on your SPID this K5 was built at the Flint plant, not the Fremont plant. I'm not sure that Fremont built Blazers/Jimmys. Looks like a nice ride though. Engine codes will help with the rest as mentioned.

[Dirt's72]

I know a guy here who has about 20 of the 67-72 various trucks. He has three that came with original corvette motors. I was suprised when he told me that they came like that originally.
Posted via Mobile Device

[rsavage]

I am pretty much a Doubting Thomas on any 67-72 truck coming from the factory with a Vette engine- it is pretty easy to tell. On the 350's the block casting number tells you nothing as the 3970010 block was used in a lot of models. If the engine had these prefixes
on the pads, along with the Vette intakes carbs etc, then I might be convinced

Here are the prefix codes on the block pad for Vette engines:
1967 327ci block casting # 3892657 Prefixes (based on horsepower and trans combos) were HE, HH, HO, HR, HP, HT, HD, KH

1968 327 ci block# 3914678 Prefixes HE, HO, HP, HT

1969 350 - three casting #'s 3932386, 3956618, 3970010 Prefixes HY,HZ,HW,HX

1970 350 block casting # 3970010 Prefixes CTL, CTD,CTM, CTG, CTN, CTH, CTO, CTJ, CTP, CTQ, CTU, CTK, CTV.

1971 350 block casting # 3970010 Prefixes CJL, CGT CJK, CGZ, (CGY = the LT1)

1972 350 ci block casting #'s 3970010, 3970014 Prefixes CKW,CDH, CKX, CDJ CY, CRT, CKZ.

All the above info is available on "Rowley Corvette" Corvette statistics.

[Big Block]

Originally Posted by rsavage

I am pretty much a Doubting Thomas on any 67-72 truck coming from the factory with a Vette engine- it is pretty easy to tell. On the 350's the block casting number tells you nothing as the 3970010 block was used in a lot of models. If the engine had these prefixes
on the pads, along with the Vette intakes carbs etc, then I might be convinced

Here are the prefix codes on the block pad for Vette engines:
1967 327ci block casting # 3892657 Prefixes (based on horsepower and trans combos) were HE, HH, HO, HR, HP, HT, HD, KH

1968 327 ci block# 3914678 Prefixes HE, HO, HP, HT

1969 350 - three casting #'s 3932386, 3956618, 3970010 Prefixes HY,HZ,HW,HX

1970 350 block casting # 3970010 Prefixes CTL, CTD,CTM, CTG, CTN, CTH, CTO, CTJ, CTP, CTQ, CTU, CTK, CTV.

1971 350 block casting # 3970010 Prefixes CJL, CGT CJK, CGZ, (CGY = the LT1)

1972 350 ci block casting #'s 3970010, 3970014 Prefixes CKW,CDH, CKX, CDJ CY, CRT, CKZ.

All the above info is available on "Rowley Corvette" Corvette statistics.

I'm with you on this one. No vette engines in Blazer's or Jimmy's or Trucks of any kind from the factory. Not unless they had a COPO Central Office Production Order like they had for Camaro's and Chevelle's. Never have I heard of anything like that in the truck division.

[Big Block]

Looks like a great starting point. This board is full of great people and a wealth of knowledge. Welcome aboard from NC.

[Big Block]

1LS910 is the same number that is on my SPID as yours, and mine was built in St.Louis.
The 1LS910 was the designation for the chevy truck 4 bolt main bearing truck engine. not all 350 came with 4 bolt main bearings. Trucks and HP passenger 350 were all 4 bolt main blocks. I think that is where people get confused and think they have a vette engine.

[Big Block]

On the front passenger side of the block, right at the end of the head you will find a pad with letters and numbers and it should start with the letter V and some numbers and end with the letters TBA. If they do, it is most likely a stock truck 4 bolt main block. and on the rear pad on the driver's side it will be the block number 3970010.

[Dust Bunny Queen]

Sorry to be gone so long....>THANKS for all the great replies. The explanation of the exhaust manifold is great. We did find a casting number on the block on the passenger side cylinder head. V0413TFJ.....so that is a start.

[Bigdav160]

Looks like that is the "born with" truck engine :thumbsup: