Help Identifying Engine

[Martin14]

Hey everyone,

I posted this same question over at camaroforums.com and was directed to you guys for additional assistance.

I recently purchased a 68 Camaro. I'm in Alaska and the car is in Ft Worth, Tx at a shop getting some minor repairs. The car has a 427 but I don't have much other information other than some of the add-ons. The shop gave me the block casting number 3938512 which he said is a performance 427 and that it was pretty rare. He's going to try and get some additional information but I told him I'd rather he focus on the repairs so I can get the car picked up and delivered to me. I did some digging online but other than flagging a couple of advertisements for other 1st gen camaros for sale (https://russoandsteele.com/vehicle-d...ge=&showpage=3) with the same casting number, I haven't been able to find much other information. None of the sites I've found with a database of casting numbers listed this particular number.

 Anyone know of a site that would give me additional information, or have first hand knowledge of this particular block?

[bcmiller]

That block was used for 427s in the 1969 model year and for 454s in 1970 and 1971. It’s not rare.

What’s the casting date and what’s stamped on the front “pad” of the block ahead of where the passenger side cylinder head mounts? 

[bertfam]

Martin, welcome to the site. We don't have very many guys up in Alaska as members!

The 3938512 casting number isn't correct and it's probably 3963512, which, as Bryon stated, isn't rare at all (casing numbers can sometimes be difficult to make out because of casting slag). It was used from October, 1968 through the 1971 model year on all 427 and 454 applications. If you can have the guy take a picture and post it here, we can verify if it really is 3963512, but I suspect it is.

The best reference material on casting numbers is Chevrolet by the Numbers by Alan Colvin (another CRG member). He has several books out with the 1965-1969 edition pertaining to the first generation Camaro.

Ed

[Martin14]

Thanks for the welcome and the responses.

I emailed the shop this morning for additional information and requested some pictures if possible. They're going to repaint the block so hopefully they can get a better look and pictures while the motor is out of the car being prepped.

[ko-lek-tor]

Welcome to CRG. As long as the shop is taking pictures, have them take pictures of the trim tag and a couple of the firewall that show the complete area, then a pic of the fuel line. Thanks. The casting number will most likely be found on the back of the block on the opposite ( right) side than the ...512 number you provided. There is a pad on the rt front with possible numbers.

[Martin14]

Got a picture of the tag. VIN 124378N481141

[dannystarr]

Rivets look to be aftermarket hardware store bought.. ?? Danny

[bertfam]

That's a very late car. A little less than 600 were built after yours!

Rivets look to be aftermarket hardware store bought.

Original tag and belongs to the car, but it's been off at some point. Probably for body work.

Ed

[Martin14]

Forgive my ignorance, but is being a late production a good thing?

I'm honestly not overly concerned about the originality of the vehicle. I've always loved 1st gens and was finally able to afford a good turnkey. My only concern, and the original reason for the post, was learning more about the engine. In Alaska, pump gas maxes out at 90 octane. With the information I've been given from the shop that this is some "high performance" 427, I'm a little concerned it might be some high compression monster for which I'm going to have to spend $$$ on additives or race fuel. I can't even get Torco shipped up here, so I'd have to pay over-the-counter price.

Hopefully I'll learn more over the next few days. Appreciate all of the input so far.

[bertfam]

Forgive my ignorance, but is being a late production a good thing?

No, it was just an observation.

That block was used in 427's ranging from 335 horse power to 435. If you can get the suffix code and partial VIN off the front pad, we can at least tell you what car it originally came out of and what the horse power was. Of course, after 50 years it may no longer be original (and rebuilt at LEAST once), so that may not help. But at least it'll give you an idea of its heritage.

Ed

[68Zproject]

I bet they have plenty of AV gas up there.

[dannystarr]

That is EXACTLY what I was going to say. We have garbage 91 locally, no 93 left in the area. I could go to Sears Point ... WHOOPS I mean SONOMA Raceway and get several different octanes but they are 10 BUCKS a gallon. I can even get 116! BUT I run AVGAS in both cars. It is 100 octane low lead and cost is $4.75 a gallon. Why pay $4 a gallon for 91 junk, another few bucks a tank full, and you are golden!    Plus it is blue dyed, so if you have a leak it stands out like a sore thumb. I assume it is for the mechanics to see any issues during engine inspections? See the front bottom bowl bolt on attached picture showing a slight leak. Had two or three of them after carb rebuild and tightened slightly, cleaned with a rag and some carb cleaner and BINGO.. Bob's your Uncle!! Danny

[bcmiller]

Forgive my ignorance, but is being a late production a good thing?

I'm honestly not overly concerned about the originality of the vehicle. I've always loved 1st gens and was finally able to afford a good turnkey. My only concern, and the original reason for the post, was learning more about the engine. In Alaska, pump gas maxes out at 90 octane. With the information I've been given from the shop that this is some "high performance" 427, I'm a little concerned it might be some high compression monster for which I'm going to have to spend $$$ on additives or race fuel. I can't even get Torco shipped up here, so I'd have to pay over-the-counter price.

Hopefully I'll learn more over the next few days. Appreciate all of the input so far.

Find out from the shop what pistons are in it and what they think the static compression ratio is. 

[Martin14]

Definitely no shortage of avgas up here. Are there any consequences or particular maintenance I need to be concerned with if I end up having to run avgas?

[68Zproject]

I've used it for 10 years with no problem that I know of.