Hi guys, I'm a new member and virgin when it comes to engines, rebuilding etc. As they say, I know enough to be dangerous and thats about it. Working with my 16 year old son on a 1965 Olds Cutlass. The car came with a 330 that ran but when we tore it down found multiple cracks in the steam ports and timing chain area. Recently my brother in law found a pretty solid engine in Montana that I believe is out of a 67 Dynamic. The block numbers are - 389244D and the heads are stamped with a C. Picked up the engine this weekend and ready to dig in. He started it prior to pulling it for us and it ran fine and looks pretty clean with some normal gasket leaks etc. The air cleaner is red and says "Oldsmobile Ultra High Compression Super Rocket" (pretty cool) on the top.

Several questions, is this a good engine? Any idea if it has the 45 or 39 degree cam? Can it be better/ideas? Any trouble throwing it into a "65"? The car came with a 250 trans that I had rebuilt and upgraded to a 350 (before I knew I'd get this engine) got about $700 into the rebuild so will the 350 work? Any suggestions, advice, etc...... Just looking for help on my sons first car and our first project.

 

That should be a good engine to use, the "C" heads would be the newer more common cam angle. I don't know for sure, but would guess it's a 10.25 or 10.5 compression ratio. Just in stock format it should make your Cutlass scoot pretty good, but yes you could change the cam and put on a newer intake and see an improvement. If you would post the city and state your in there may be someone close by who can be a resource for you and help with any problems you encounter. John

 

Thanks John, in Oregon City, OR and looking for any local expert advice. Your thoughts on the 350 tranny versus a 400?

 

For normal street driving I'd be comfortable using a TH350 behind a big block. If you plan to race it, then you'd need to go with a TH400 or build the TH350 to take the punishment. There's been a couple discussions on this board about the two trannies. One comment is that the TH400 will take more energy to operate, and lose more horsepower to the wheels. If you go with a TH400 you'll also have to have a driveline built, that will add to the cost of the TH400 swap. Have you been to Supercarsunlimited in Portland? Greg is a great guy and has been playing with Oldsmobiles for many years. He advertises that Oldsmobile is all he does, so you can know your getting the right parts the first time. He's got a web site, I think it's supercarsunlimited.com but if you have the time to stop by his shop and talk with him in person you might get a peek at his collection of Olds iron. Welcome to the world of Oldsmobile!!! John

 

Thanks for the info on Greg! Looking forward to getting to his shop sometime this week. Since this is our first project need some advice though. I've got the 425 on an engine stand, pulled the plugs and did a compression test (I think I did it right?). I simply hooked up a battery, screwed in the gauge and turned it over until the pressure quit rising (probably about 8-10 times on average). First is that the correct way? Second, these are the readings I got using this method 1-100, 3-125, 5-105, 7-100 2-120, 4-110, 6-115, 8-100. Are these readings OK or should we have a ringset put in? Thoughts?

 

If you have the money I would rebuild it before putting it in the car. I think your method was correct, and you have 25 pounds between the weakest and strongest cylinders. I believe that's enough that you wouldn't get the full potential out of the engine, and it may smoke or foul plugs. The effort to pull the engine out and rebuild it if your not happy with it, or after you put a few months of driving on it is more than I would want to do. I realize how much money you can spend on the car is a deciding factor though. I'm trying to remember a trick I once heard, I believe you squirt some oil in the spark plug holes and do a compression test again. If the compression goes up it shows the rings are weak. If the compression stays the same it's the valve guides that are letting pressure by. The other guys can chime in if I'm getting that wrong. If money is an issue you could try that first and see if you could get by with just doing the heads right now. John

 

It's never bad to rebuild an engine, but the diffference in the comprression readings are less than 15% so I wouldn't worry too much. Removing all the spark plugs during the test is the most accurate way, that way none of the cylinders are loaded down during the test except the one under test, you did that right?

 

Thanks guys, once I pulled the heads I had some issues (oil on the piston tops and bottom of the heads) so tore it down completely. Found 1 piston broken on the bottom and a crank that needs a little work (turned is probably all). The rest looks fine but since I need one piston decided to have it bored, crank turned and the heads done. The guy working on my heads is an Olds guy that has his own project going. He's suggested that instead of valve guides that he'll bore them out for oversized rods. He says its a bit cheaper and probably better in the long run. Any thoughts? Also looks like my water pump from the 330 will bolt onto the 425. The reason I want to use it is the discharge side matches with the "65" radiator and the water pump thats on it is on the opposite side. The water rotors are slightly different but other than that they look pretty much the same. Any issues if I use the water pump off the 330?

 

Thanks for everyones help, heres the current status and a couple questions as I get the motor back Monday!

Thanks to 2blu442 for encouraging a full tear down as we found a broken piston and a crank that need to be rewelded and turned. Good news though, the crank is done and looks great! I've had the "C" heads completely rebuilt and the the block goes into the bore Monday morning so she'll be ready for assembly (finally) and onto the fun stuff.

My questions are as follows though (keep in mind it's a 425 from a "67" Dynamic and I'm bolting this into a "65" Cutlass with a rebuilt TH350):

1. The old 330 had duel exhaust and the 425 single. The manifolds look indentical any problem using the duel exhaust manifolds from the 330 on the 425? Any performance loss?

2. The 330 had a 4-BBL carb and the 425 has a 2-BBL. I'd like to use the 4-BBL from the 330 but can't determine what type it is (it was an add on). The following will describe it to the best of my abilities - The only markings I could find on the very bottom of the flange that bolts to the intake was a C6 and on the other side the numbers 587 9635SA. It has a round brown adjustment on the side that says "lean" with an arrow and has wires to hook up electronically. It was bolted to the 330 on an aluminum spacer that Im assuming was in place in order to keep the butterfly's from hitting the intake manifold? Any ideas or way I can determine what it is?

3. If I switch the carbs, obviously I'll need a new intake manifold. Any reccomendations? Will I have interferance problems with the hood on the "65"?

Thanks for your help so far, it has been invaluable and saved me countless hours in potential rework!

 

you can use either a stock 350 manifold from a 1968-72 350 with no EGR, or find an aluminum A-4 manifold from a later model 307. it has an EGR port, but can be blocked off.

Then there is aftermarket stuff...Edlebrock RPM is great for a stock type application. it sits right about stock hight and does not cause clearance isssues..

If those 330 manifolds are true dual manifolds, (no crossover port) they are worth holding on to for someone doing a numbers matching concourse restoration. The manifolds will bolt to the motor but custom pipes will have to be made and there may be some clearance issues with the starter and the Oil filter. The 425 is a wider block, so the bends in the 330 manifold will be different.

John

 

i don't know about those years, but later pumps came in different sizes, meaning the lenth of the shaft where the pullies bolt to could be different. If all the 330 bracketry fits, the only issue you will run into is getting longer belts as the 425 is wider. And use a NEW pump on the rebuilt motor. Do NOT use the old one, and get the radiator, and heater core flushed in the process. You wont be sorry.

John

 

On a 425?

Norm

 

Nope...probably why i should not be trying to give out advice while I am tired... I thought for some reason he was taking OUT the 425 and putting back the 330. DUH.... thanks for the kick in the ***.

My apologies...Oldsproject.... But I still recommend the CORRECT Edelbrock BBO manifold.

John

 

Thanks everyone for a good post. I've learned a few things along the way myself.

You guys lost me on the exhaust manifolds. Was it cleared up that the dual setup from Oldsproject 330 ci motor work with the 425 block? Mine has a 'cheap' solution to duals as the right side manifold had a 'plug' made for the crossover, allowing duals to flow free. I'm sure its not the best solution for power but does have some gain over single exhaust.

I am very happy with the Edelbrock Performer manifold and carb duo. When I got the car, it had a very low profile (10" x 1.25") Edelbrock air cleaner. I cold feel it starving for air when I let the 'big boys' (secondaries) open wide. It solved the clearance issues but choked WOT. I replaced it with the Edelbrock 'tri-flow' and now the boys can run free.

Here's a couple pics of the engine bay

Sounds like a cool 'street sleeper' Cutlass. Your son has a great dad.

FRDMFTR

 

Thanks for everyones help so far. I'm also still interested in the exhaust manifold switch if anyone knows?

Also, looks like the carb is an edlebrock based on pictures I've looked at but again can't identify which one and how old. Any ideas?

To refresh it was on my "65" 330, is a 4 BBL that had an aluminum adaptor under it and I'm thinking about putting it on the 425 in place of the Rochestor 2BBL (realizing I'd need to change Intakes). Has the following numbers stamped on the bottom flange 587 9635SA (front left side) and C6 (or possibly C8) on the back right flange (facing the car).

 

Well, things are changing a little as we get deeper into this project. After reading numerous threads and articles (this site is great!) we've decided to get a little more aggresive on the engine rebuild but need advice.

First, We've decided to upgrade from a 2BBL to a 4BBL, next we're upgrading the pistons for better performance and durability, third we're having the crank balanced, forth we're going to a more aggressive cam (perhaps with a 2000 stall) and fifth we're upgrading the springs etc. in the heads (to compensate for the more aggresiive rebuild).

Now for the tough question, I need reccomendations on a cam. Keep in mind that this is a 425 bored .060 with C heads and mounted to a TH350 in a "65" Cutlass (or will be).

Also, I"ve been reading a lot about the oiling concerns with these motors. Right now (unless theres better advice) I'm not planning to change anything on that end. Staying stock with the stock pan and oil pump from the "67" Dynamic.

Also, any idea what kind of horse power we're looking at (assuming a decent cam) and am I now starting to over power the TH350 (we will not be racing..... well not unless provoked )

Final question (and I promise I'll quit bugging everyone) I tried to figure out what gear ratio I've got in the "65" F8 Cutlass we're working on. I spun the drive line until the wheel turned 10 times as outlined in other threads. Here's what I got (which is confusing to me) the drive line turned approximately 15.5 times to 10 complete wheel rotations. That seems really low? Can that be right? It's a 10 bolt main.

 

I'd recommed talking with Greg at supercars for your cam decision. Describe to him what you want out of the car and ask him what grind he would recommed. I know the 1967 factory 4 bbl Toro 425 advertised 385 hp, so if you do some tweaking on yours you may be around the 400 mark. But I'd be looking at the torque if your thinking about overpowering the TH350, I believe that's what would cause you problems if the trannie isn't strong enough. I'm pretty conservative with the way I drive. As my sisters grandson says the car looks and sounds mean enough I don't have to prove it to any young guy in a rice burner. I agree with the stock oiling system, the high volume pumps can cause problems in some situations. For gear ratio I like to pop the inspection cover off and read the numbers stamped into the ring gear. I've not had good luck turning the input and counting the rotation of the tires unless it's a posi. Back to the exhaust manifold, attached is a couple drivers side exhaust manifolds, the bottom one is from a 350 the top one a 455. You can see the difference in size, so the small block ones would restrict the flow somewhat.
P1010053.jpg

 

Thanks 2blu442, I agree on the torque issue that's a concern that I'll look into. Any reccomendation on headers? I'd like to avoid the typical problem of rerouting stuff if possible.

 

Don't know about anyone else, but I need to know more about this procedure.

It won't clean up at thirty?

Based on your stated use, make sure the main/rod/rod side clearances are all set at maximum factory tolerances, and the pickup clears the pan by at least ¾".

Always use a new oil pump on any rebuild. If you feel the need to cheap out, do it somewhere else.

If you restrict the pushrods, using "pipe cleaners", you might get by using a stock replacement instead of a high volume pump.

X 2 = 3.1 = 3.08 to one. Same as my '65 Cutlass.

No. 1.55 would be a high gear, not low.

Norm