70442rag

I have recently received an Olds big block which I intend to purchase (I think). The casting numbers appear to indicate a 1967 Olds 425. I was told that a 455 reciprocating assembly has been put into this block. It has been bored 30 over with forged pistons and has the stock 455 Nodular iron crank and rods. I have attached a couple of pictures for your perusal. I am trying to ensure that I am buying a big block with a 39 degree lifter angle versus a 45 degree lifter angle. I have tried to locate the drill spots that some make reference to but cannot locate any. Can you please observe the attached pics and let me know what your thoughts are specific to either a 39 or 45 degree lifter angle block? I want to change the cam and lifters in this block and add a set of modern aluminum cylinder heads. I do not want to spend extra money on re boring the push rod holes to accommodate a 45 lifter angle or on getting a custom cam grind.
Thank you for your consideration!
Regards,
Brad

GAOldsman

You have a '66-7 425 Big car engine and if it has no drill spot then it is the 45 degree Another way to check is to measure lifter bore diameter. 0.921" = 39 degree
Scot

geckonz08

below the tip of the screwdriver--the "drill spot" on a 66 toro
mike

aliensatemybuick

It has been suggested (though I cannot confirm that it is DEFINATIVE) that if your motor does not have the larger lifters (i.e. aint a Toro motor), comparison against THIS pic will tell you which lifter back angle you have:

Run to Rund

Note the two blocks above have no drill mark next to the oil filler hole. They have small lifters and the drill mark therefore must be for large .921" lifters, not the lifter angle. All 389244D 425 blocks with .921" lifters are from Toronados and are 39 degree.

70442rag

Hi Guys,
Thanks for the responses thus far. The short block I have has the smaller .842 lifters and no drill spot....does this mean it is automatically a 45 degree lifter angle block?
Thanks again!
Regards,
Brad

GAOldsman

Unfortunately that would be correct.
Scot

aliensatemybuick

Actually, it would NOT.

I encourage the original poster to re-read what Lund wrote (suggesting that the drill spot is NOT definitive either way of 39 or 45 degree LBA). I also enocurage him to look at his engine and compare the lifter gallery to the photo I hyperlinked. That assumes the intake manifold is off, but then there will be NO knowing for sure otherwise. Even without seeing it, I would bet that ANY 1967 425 would be a 39 degree motor, as I think the vast majory of '67 motors were.

GAOldsman

aliensatemybuick

Gynormous unreferenced table aside, it has already been documented by people on this site and elsewhere that you can have a 39 degree non toro 425 and no drill spot. In addition to the photo I linked to showing the lifter gallery area, a 45 degree LBA motor will have lifters with the exact same angle off centerline as the cylinder bores (and a 39 degree motor won't). If may be hard to see this by the naked eye, but some have built tools to determine whether this is the case. A keyword search of this site will show posts related to this.

Jaybird

I have two '67 425's. More definitive information would be greatly appreciated.

Thanks,

Jaybird

radioburningchrome

Where would one find the casting letter for a 1965 425?

After reading this post, I would like to find out.

geckonz08

Looking from the vehicle front.....
To the left of the oil sender to the right of the oil fill tube (as shown above in my previous post)
mike

70442rag

It has also been suggested to me that because the casting of this block was on the 287th day (as per the photo I posted above), it was late enough in the production run of 425's that they stopped creating drill spots as every 425 from mid to late 1967 were automatically a 39 degree lifter angle. This tends to suggest that there was no sense designating one from the other anymore by virtue of creating a drill spot...
Regards,
Brad

2blu442

Brad, if your not sure this will work for you I'd encourage you to create a post in the parts wanted section. Lots of members here have extra engines, and depending on what part of the country your in you might be able to pick up a rebuildable 455 at a reasonable cost. John

aliensatemybuick

Not sure I buy that, as Day 287 would be in mid-October, and I would expect then that your motor was built in late 1966, not late 1967 (by October 1967, wouldn't produciton would have moved over to the '68s (and thus 455s rather than 425s)? I admit I do not know what the changeover date was...but I sure would expect it to have been before October 1967. Perhaps others can comment on that.

Ultimately, the safest bet would be to check visually/ measure, but my money is still on it being a 39er.

7-d442

67 non Toro 425's were 39 degree D blocks no drill spot. Take a 12 inch piece of pvc that will fit in the lifter bore with heads off cylinders are bored @ 45 degrees to centerline place the straight edge of a square or any true right angle on the deck surface and if its parallel to the pvc pipe its 45 degrees! That simple. Good luck.

Jaybird

7-d442... That sounds good. I will try it.

Thanks,

Jaybird

therobski

Okay for S$$ts and Giggles here is a few pictures of my 65 45 degree 425 block.

Boldsmobile

I have one of those too ........ it was listed on Craigslist as a 1968 455 from a Delta. Seller didnt even take the time to look up the casting numbers. I love buying 425s for 455 prices.

IMG00208-20110426-20461.jpg

copper128

This photo is how I confirmed the '67 425 D engine that was sold to me as being a .842" lifter, 39 degree block was, in fact a 45 degree block. After comparing it to the photo, it was obvious
I replaced it with a '67 Toronado 425 (with drill spot) block, then spent plenty to have the lifter bores bushed for use with .842" solid roller lifters.

copper128

Further evidence that the drill spot is not an indicator of LBA is that the same situation (changeover from 45 to 39* LBA) occurred in the 330 small blocks, yet 330's never had any outward indication of which LBA they were machined for. If Olds didn't bother marking the 330's, why would they do it with the 425?
Simple answer: They didn't. I agree that the drill spot almost certainly indicates lifter size (.921"). It was ONLY used on pre-68 big blocks, and they were the only modern Olds engines to receive the big lifters.