There is a guy selling just a 425 block locally and cheap, I think he wanted $25 for it or something. Do you think it would be worth picking up just the block to start a build on or do you think the total cost and time of searching out all the accessories would take too much?

 

Yes, it is worth it if it is a usable block.

 

If it is just the block then I wouldn't go for it unless you have plenty of time and space to store parts. You will need a crank and heads before you can even start thinking about a rebuild. Then again the price is right. If it were me I would look for a BBO with everything from the carb to oil pan to do a rebuild.

 

I'm thinking if the block is in good shape $25 is inexpensive if I decide to not use it. What would I check for to make sure the block is in good shape.

 

$25?? If it looks any kind of good, I'd get it. I bought a 455 from Oil pan to intake for $75. After looking closer, although its in great shape, I now see where at one time part of the block where the bellhousing would bolt in had broke at one time. They put the piece back in and welded it. I guess it looks OK, and will hold, and looks like an OK repair, but I know its there and thats enough that I want another block and $25 would work. In fact that is what I am now doing with my 425 block 39 degree, common lifter block. Its going to be a 455 cu in motor. I also still have my crank for the 425, but I would need to find Rods, pistons, flywheel and balancer, so its much cheaper just to go with this 455 rotation assembly into the 425 high nickel block, which I guess to some means nothing.

 

Yeah, I'm one of those people. I'm trying to bust that high nickle myth. So far I can tell you that there is virtually no nickel in '67 400s. I expect to eventually test representative blocks, 400s thru the fabled 455 "high nickle" years to officially put the rumor to rest with proof positive.

 

Yes, I seen that W. I was curious as to what you meant by that statement when you made it and what you are trying to prove. I guess now you clear that up. My question was, that they did NOT have high nickel in them, or that the high nickel in the block was not a benefit. That would be an interesting thing to find out for sure.

 

I contend that:
1. They did not have high nickel in them.
2. High nickel would not improve strength and/or wear-resistance. Nickel properties as an alloying element are what made me question this to begin with.

Fortunately, #1 *is* something we can find out for sure by testing the material.

 

I think I might pick up that block for $25. It says it's been hot tanked or whatever and he says it appears to be in good shape. He bought it a while ago to start a build and never pursued it. What would be the route for building this thing in everyone's opinion? I assume all the 455 parts bolt onto this thing, including heads and perhaps 455 crank. What would be a solid build with all this. It's a '65 block.

 

Chances are if he had it hottanked, most machine shops, magnaflux it at that time too. So unless the guy would lie to you, its probably no cracks and a good block. All your 455 rotating assembly will fit in it, but be sure to use all 455 rotating assembly. Crank, Rods, Pistons, Flexplate/Flywheel and Balancer. No mix and match with 425. Either one or the other. Also keep in mind, this block unless its a Toro block will be 45 degree cam bank angle. Mondellos and Comp Cams have the cams. Also if it is a Toro block and 39 degree CBA, then it will have the .921 lifter bores.

 

Kurt- not sure I agree with you on the benefits or non-benefits of nickel. Mercury Marine came out with Nikasil (Nickel derivative) bores on the their race blocks in the late 70's. Dramatically improved wear characteristics and ring seal due to less cylinder distortion.

 

That may be true, but I think Kurt's point is he doubts the claim of "nickel content" in the block...is it a proven fact? Has anyone tested to be sure(a lab), is it a myth? I believe nickel is a "soft or more malleable"(sp?) alloy. But I'm not an expert on metals so....

 

Yes, it would be interesting for someone to find out. I am interested in both. Does it have better wear charachteristics #1, and #2, do the blocks really have more nickel in them. I can not say on this 425 block I have since I do not know the history of what, where and when it came out of the car and set in the pasture. But this 67 block is standard bore, the crosshatching is not able to be seen if any due to the shiney glaze in the cylinder, but the machinist measured the cylinders, and their is not even a ridge in any of the cylinders with exception of one for some reason. He said, I could get a good hone on the block and rering it and run it without a bore job. It would be nice to know how many miles where on it before it was removed from the car.

 

Right to both of you. There does seem to be enough evidence out there that there is some superiority to Olds blocks in strength and wear to the cylinder walls. But I just don't think it is due to nickel.
I've tested 2 400E blocks and found virtually no nickel. What I *did* find is some chromium. And that *does* make sense for more strength and wear resistance.
But the beauty here is that we don't need to theorize. All we need to do is test. And I need more samples to test!
https://classicoldsmobile.com/forums...ur-engine.html

 

You are to far away for me to make any donations. I have a 71 455 block that may be able to be a test block. I am sure your efforts and findings of these tests will be appreciated by many. It would be interesting to see how much chromium is in the newer Olds blocks and Chevrolet motors. Another thing about this 425 block I have, it was a rust pit. I used electrolysis process to clean and de rust the block and expected some rust pitting. None to have been found. Not a bit of pitting anywhere on the block. Not in the valley, the cylinders, or anywhere. What element could be in an Olds block that would resist rust pitting??? It be interesting to find these things out. BTW, if anyone is interested in seeing an eletrolysis project on a 425 block, let me know. I will start a new thread about the process. Its pretty fascinating and I was impressed and suprised with the results.

 

I've seen the 500 cu in stroker kit from dick miller for big blocks that I thought might fit real nice in that 425 block. haha! If I only had the money! Any personal recommendations on a good budget build using this 425 block that would make a good 400-500 reliable hp and maybe run 12's or 13's in the 1/4 mile in the 68 cutlass coupe with a turbo 400 tranny.

 

If you decide to run the 4.25" stroke crank from a 455, be sure there is enough rod nut clearance at the bottom of the cylinders. You may have to do some grinding.

 

Ok, so I just went and picked up the block. It has a big A stamped on it and he said the only thing he knows is that it is a 65 425 block but no idea what it's out of. It has been hottanked and it's nice a clean and it came with the main caps for the crank. My guess is that it has the 45* angle cam bank. I'm not sure what that means for searching out parts but I'm anxious to start finding some. All the big block heads will bolt whether I find a 425 crank or a 455 crank I assume. Any advice on where to go from here. This is my first engine build and I already bought the DVD's on engine rebulding that were recommended on here.

 

Great !!! It should be just any other build and the cam should be the only thing you need to make sure is correct. Mondello's has them, I think for $149.95 which for Mondello's is very reasonable. It will be an Engle Cam. If it were me, I'd build it 425 if you can find the parts. Probably a bit more expensive and a tad harder to find, but just to be sure you don't have to do any block grinding for the 455 counterweight throws to clear. It is an agruable factor which could be a more powerful motor anyway. 425 or 455. You are talking 30 cubes differance. Sure there is no substitute for cu in, but with that extra 30, you also add additional friction to will absorb some of the differance. The 425 is also going to be a forged stronger crank, and with a shorter stroke, the 425 should get the RPM up a bit faster. On that cam, Comp Cams also has some 45 degree cams for BBO which you will have to do wether you do 425 or 455 either one. On the other hand, I am sure 455 parts will be easier to find, and probably more choices. You mentioned the main caps are there? Are they in their respective locations? Very Very Very important that they are. Hopefully they are marked. My 425 has factory marks on the caps with #'s and of course the rear main is obvious. Do you know if your block is Standard bore or has it been built before?

 

I'm not sure if the block hasbeen built before. I will find out soon enough. What heads would be best? I'm thinking of maybe doing everything 425, from the crank and pistons just because it's different. I've heard c heads are good but will edelbrock or other aluminum heads bolt up with it being a 45* motor. Also does this pose a problem using an aluminum intake? I'm going to start compiling parts and if I can build a solid 400 hp 425 motor I'd be happy unless everyone recommends going with 455 crank and pistons. I need some info on a good 425 400-500 streetable hp going the cheapest and easiest way since this is my first build.

 

You should be fine with A & B for sure. C should be OK too since according to Olds442, the C had bigger push rod holes to accomodate both cam bank angles. I would not be positive on the C heads though wo checking first. Really should not be any big deal on any BBO head, but stay away from J. J is the step child smogger BBO head you don't want. And if your push rods happen to rub in the head, then you will have to make the holes bigger is all. Once you address that issue, of getting the right cam, and making sure your push rod holes are OK, it all the same as building any other BBO. Aluminum intake will be fine, headers if you want to use them etc, all will be fine. If you can find stock 425 pistons as far as compression height and CC volume of the piston, you should easily be able to get 400hp. That will give you a 10.25/10.5 to 1 ADVERTISED compression ratio. Using a common aftermarket head gasket that should come in your gasket kit about .040 thick, will drop your ratio some, so if you choose to either deck the block and/or mill the head, that will compesate for some of that thicker gasket and get you back close to the factory advertised ratio. I would not get to crazy on milling the head or decking the block. I would do just what is necessary. Like with your valve job, they should resurface your head, that will take off a few thousandths. If the machinist thinks the block needs decked, then let him do just enough to clean it up to have a nice flat surface. Even with just resurfacing, taking off the minimum and using the aftermarket thick gasket, you should still be in the 9.5 or better compression ratio. Then with a mild cam with some valve overlap, you will lose a little more compression which you actually want to so that you can run pump gas. Its kind of hard to have fun with a home built street/strip engine when the compression ratio is so high, that you either have to buy expesive race fuel or retard the timeing so bad to run pump gas, that you actually take away the power you built. Also do not forget to get hardened seats put in the exhaust valve seats for unleaded fuel. Some disagree and say its not necessary. I believe it should be done, and I have a set of heads to prove it. The exhaust valves are so recessed, I am suprised the valve keepers did not fall off and drop the valve in the cylinder. Also with this build, be sure to balance all your rotating assembly. Crank, Rods, Pistons, Flywheel/Flexplate and Balancer. I think the alumiunum intake is a great choice being that you do not yet have an intake at all and you are not doing a car restoration project, you are just building a motor for a project street rod. The aluminum intake is lighter and will also give a better throttle response. I would not go with a Torquer single plane manifold. Sure it sounds impressive, at 2000-6000 rpm power band range, but even if your cam has that range, I would stay with the Performer dual plane intake. The dual plane will give better botton and mid range power, along with better idle, and fuel economy. The Torquer will give mid to higher end power and you apparently are not supposed to build an Olds for hight RPM anyway. I would not exceed a 750 CFM carb, and I would avoid double pumper carb. So thats just my opinion, and from my recent learing of getting to know a bit about Olds. If anyone disagrees with me, by all means, feel free. I am not an Olds guru and still learning myself, so if I am wrong, please correct me where needed. I am going to be building either a 425 or 455 myself. So far I am leaning toward 455 since I have already acquired a Nodualar 455 crank, rods, pistons, balancer etc. I will be using my C heads on my build that came off my 425 block. I really want to do the 425 since I have the crank already, but then I need to acquire the flexplate, balancer, rods and pistons. If I do that, then I can just rering my 455 for a back up motor, because I intend to give this 425 pure hell if I do it. I really want to be closer to 450-475 hp.

 

Tanks for all your help man! This board is great and it seems like everyone is always willing to help. I'm sure I'm gonna need a whole lot more of it since I'm starting with with literally a bare block with nothing on it but the main caps. They are numbered and I think they are in the wrong order. I'll take a pic and post it. I'm doing all this while trying to rebuild the suspension in the 68 cutlass while attempting to get that 350 rocket running decent too. I think that may need a carb rebuild too, but I hate spending the money on it knowing i'm gonna need to get a carb for the 425, but the 425 is gonna take quite a while to finish.

 

Then I thought about maybe buying a JET performance rebuilt quadrajet, which I heard were decent, that was 750 cfm and bolting that on to my 350 until I get the 425 running.

 

That's not a bad idea. Just buy for the 350 what you can later convert and use on the 425/455. So you are putting this new build in the 68 Gutless and going to make it a Cutless? If that's the case, you are not doing a restore project either, so # matching is not important. You may also choose to go 455. I think the 455 parts are going to be easier to find and probalby less $$. That is what I have let be the deciding factor. Parts availability and price, although, I'd really like to do the 425 and use my forgerd crank. Keep in mind, as you do you build, there are also tricks and things to know that will make it better. Example, I believe (not 100% positive wo checking first) its a Ford 460 rear main seal that you can use and then have a 2 piece rear main instead of the rope 1 piece. Also use a 350 Olds Diesel Oil Pan gasket, it works much better and will not split or slip out. Minor things like that to know make a huge differance in the end. There are some things you can use off your 350 too. Valve covers, Oil Pan, if you don't upgrade it. I would go with Big BLock exhaust if you don't already have headers on your Cutless. Do alot of reading on Olds442, but keep in mind, there are some inaccuracies there too.