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Old 05-13-07, 10:24PM   #46
otistn
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Re: Oakland V8 Discussion

I will take a nother look and see if i can find any of the missing peaces
it will be mid week befor i can do it but that stuf has set there over 3 years
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Old 05-16-07, 02:27PM   #47
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Default Re: Oakland V8 Discussion

Rarerodder, you might be able to find a supercharger off of an old Studabaker. They had them in the 50's. The valves look pretty long so the valve guides are probably long also. If so, they can be trimmed down to increase flow probably rather significantly. Some valves seats that are radius cut and maybe some slight porting I think you could easily expect over 100 HP from it. If you supercharge it, maybe even 150 HP. If you can post rod bearing journal diameter and width of the crank, we may be able to find a better rod that will work so you can run bearing inserts. Put a long rod in it with a short, light, piston and it would do pretty well I think. There may be something we can do with replacement valves and modern keepers also. Maybe something with a slightly bigger head diameter and smaller stem diameter so a nice entry can be cut in the valve seats. There is possibility here. Looks like a cool project to be involved with. I wouldn't mind helping you out however I can with maching or coming up with parts to work. Just say the word! I love challenging projects like this.
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Old 05-17-07, 03:04AM   #48
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Now you guys got me thinking trubo or blow though. Been talking to the P-Dude, he said he'd fly up to rhode island and tune it for me...LOL
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Old 05-19-07, 09:12AM   #49
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Default Re: Oakland V8 Discussion

Thanks for your input Paul. Valves are 6 1/2" long overall. Stems are 11/32". Guides are 3 11/16" long and 11/16" dia. Protrusion into port is 5/8" dia by 1/2" long.

Crankpins are 2 1/4" dia. Rod big ends are 1 5/16" wide and rod centre distance is 6 5/8". Piston comp height is 2 1/4". Certainly plenty of room for a longer rod but hard to find one for such a big journal I think.

What do you think about the pop top piston with 100% squish area for a higher compression ratio?

Rarerodder, are you sure the cam is NOS? That would be amazing. The rollers that run on the lobes are 1/16" or so narrower than the cams so they tend to wear a track in the middle of the lobe. What diameter are the base circles?
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Old 05-19-07, 03:19PM   #50
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Default Re: Oakland V8 Discussion

Hugh,

I have to retract that NOS statement. I first thought so because of two things: 1) the cam had a tag on it to identify what it was for and 2) I could not detect any wear at first glance. However on closer inspection after brushing on some surface rust, I can now see the grooves in a few of the lobes.

I'm not sure what you are refering to as the base circle? The bearing surfaces dia. is approx just over 2" or 52.5mm. (my battery in my calipers is dead so I had to approximate with the manual scale).

To all,

To clean the surface rust off of the crank, cam, and tappet pivot bar will take some grinding. Will I be able to have produced new bearing/bushings to overcome any material removal? Will cam require welding then regrinding? My past experience with engine rebuilding has always been to simply purchase new cranks and cams. So some of my questions may be alittle elementary to you seasoned engine restorers. In fact I would really appreciate if you guys would go thru the process of the obvious steps (aside from the modifications for performance which we will continue with as well) that I will need to go thru with this motor. Keep mind that everything has a coating of surface rust but nothing is pitted badly, including the block (which has the most rust). For instance, on the two angles of the head mounting surface, any machine work I do is gonna affect the alignment of the heads to the block. Will I have to come up with thicker gaskets to take up the small amount of material to be removed? Is it possible to produce new cam bearings, etc? New valves with improved keepers? And, anything else I may not be thinking of at this moment.

Like I said earlier, I have enough experience for basic rebuilding but I don't have the experience with something that is going to require some re-engineering and metallurgical updates. I can and want to learn, though!
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Old 05-19-07, 10:23PM   #51
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Quote:
Originally Posted by Rarerodder View Post
I'm not sure what you are refering to as the base circle?
If you imagine the cam lobe as a circle with a lump on it, then imagine the area where the valve is closed - this imaginary cirle is the base circle.

An old trick is to reduse the base circle to make the lobe "bigger" incomparison to the original base circle.
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Old 05-19-07, 10:25PM   #52
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Quote:
Originally Posted by Hugh Venables View Post
Crankpins are 2 1/4" dia. Rod big ends are 1 5/16" wide and rod centre distance is 6 5/8". Piston comp height is 2 1/4". Certainly plenty of room for a longer rod but hard to find one for such a big journal I think.
sounds about like a Pontiac V8 rod spec

how wide are the rods at the big end? ...maybe they can be made to work with Pontiac rods...
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Old 05-20-07, 02:58AM   #53
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Default Re: Oakland V8 Discussion

Quote:
Originally Posted by Hugh Venables View Post
Valves... Stems are 11/32"...
Crankpins are 2 1/4" dia... rod centre distance is 6 5/8".
Amazing coincidences with our "modern" Pontiac V8 engines!

Oops- I should have first looked at InjunTom's post on this page!
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Old 05-20-07, 03:06AM   #54
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Injuntom, Rod big ends are 1 5/16" wide. I can't imagine any modern engine with big ends this big and wide, except for diesels maybe.

Rarerodder, you're standing there looking at these rusty shafts and I'm not so it's a bit hard to advise you. Remember that when steel rusts the oxide layer that forms on the surface is theroretically seven times as thick as the steel it replaces so it probably looks a lot worse than it is.

I would try very hard not to reduce the diameter of the rocker shaft. It mounts straight in the block so you would have to sleeve and align bore all three holes in the block. You would have to also make and finish sixteen rocker bushes. The shaft and bushes are so large that they usually don't show much wear. Start with a bucket of water or kero might be better and a sheet of 1200 (800 if it's bad) wet rubbing paper and see how well it can be cleaned up. If it is still badly pitted enough that you are worried that it will scuff the bushes then the best thing would be to have it ground down, hard chrome plated and ground back to size. I had one done like this for our Indy car project. It cost us about AU$200 (US$150?) three or four years ago. You may be able to increase it's diameter half a thou or so to reduce the clearance to the rocker bushes. You would need to give the block to the people doing the grinding to measure the housing bores in the block. We are going to have to lightly hone one of ours out the fit the shaft as it now has a slight taper on it.

The three cam bearings are made from cast iron and are replaceable but a lot of work to make and finish and they usually don't wear much either. They are also three different diameters. Try the wet rubbing on the journals and lobes an see how it comes up. Be very wary of having it reground to a different profile. The stress between the curved roller and the lobe is much higher than it is with the much more common flat faced cam follower. If you have a cam that doesn't have any lobes that have disintegrated you are already very lucky. As Injuntom has pointed out, it is common to reduce the diameter of the base circle to increase the lift. This shaft is case hardened steel and the case is only about 0.060" deep or so. Reducing the base circle will also reduce the case thickness on the quietening ramp.


The surface finish on the crankshaft journals is much more important and they will almost certainly have to be reground. (I think you strange American people call this "turning" the crank, but is in fact done by grinding!) Someone will have to make a tool to unscrew the unusual cross headed screws holding the counterweights on as the counter weights overhang the journals.

Machining of the gasket faces on the heads and block is OK but tricky and you will need to find a machinist who is a cut above the rest. The angles must remain the same if the gaskets are to seal. Machining of the faces on the block is especially tricky as the two surfaces must intersect each other without either of them undercutting the other. If a lot is machinied off it may be necessary to drill the bolt holes oversize as the three rows of bolts are at three different angles. Keep your eye on ebay for some NOS head gaskets. They will be accurate while hand made copies may not. Two versions I have seen did not fit at all well and the roadsters engine had three rusted out bores when John bought it because of poorly made gaskets.
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Old 05-20-07, 03:24AM   #55
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Default Re: Oakland V8 Discussion

RareRodder- Just my opinion- if I had parts that rare, I would initially de-rust them by glass-beading, which will NOT remove any good metal. And change out the media in the cabinet fairly often, so it doesn't get very contaminated with rust particles (which can 'dent' the metal's surface). I'm sure other media would also work well (walnut shells?), but I only have experience with glass-bead. I would postpone any decision about machining/grinding ANY part until after glassbeading.

The base circle of a cam lobe can be measured directly, by placing calipers (or micrometer) across a lobe (measure 90 degrees to a line through the center of the lobe). No cam has more than 360 degrees duration (180 cam degrees), so there's always room to directly measure the base circle.

Yes, you'll need to be concerned about the angled head surfaces. But I'm guessing it won't be a big deal. If you have to mill, say .010", off both surfaces of a head, the headbolt holes might even clear without enlarging/elongating them. And a .010" change in alignment of combustion chamber edges probably won't hurt anything.
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Old 05-21-07, 11:03PM   #56
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Default Re: Oakland V8 Discussion

Thanks Hugh and Jack,

Good information! I'm traveling again but when I get home I'll get pics of the rust issues for your opinions. What about dipping the block, heads, and other parts? Have a local engine rebuild shop close that will do it. Not sure about using them for the machining. Maybe let them look at it and then make my judgement. They do alot of late model engines and have a good reputation, but this would definitely be a new one for them.

Hugh, do have torque values you could shoot to me? I've learned the hard way from one of my Pontiac sixes that there are the factory torque values and then there's the 77 year old motor torque values. What has been your experiences?

And feel free to call me Rick, all my other friends do !
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Old 05-22-07, 09:30AM   #57
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Rick, it probably depends what solution you are going to have it dipped in. Engine reconditioners over here use a solution that is mostly caustic soda I think. It is effecive at removing paint and grease/oil. I don't think it will do much with rust. I failed HSC chemistry so I'm not the best person to advise you about rust stripping but I am sure there are solutions that will strip rust. Getting the rust out of the water jackets is a very good idea.

Oakland and Pontiac in 1930 didn't recommend any torque figures at all. In fact the Pontiac has one head bolt that is difficult to get a socket onto and there was a special curly spanner as a factory special tool to tighten it. The big end nuts on the Oakland are castellated and are supposed to have split pins through a hole in the bolts. No way can these all be tightened to the same torque.

I personally am not too comfortable working without a torque wrench. I established what I thought would be reasonable tightening torques by looking through workshop manuals for other engine makes and borrowing the torque figures for nuts and bolts of the same thread. This can be risky because the safe torque for a bolt will depend on it's tensile strength which is unknown for our bolts. The cylinder head bolt holes in the block are tapped through into the water jackets which means the ends of the bolts are usully a rusted mess. The original bolts are 7/16"UNC and have 11/16"AF heads. If you buy bolts from a hardware outlet they will have 5/8"AF heads which looks wrong to me. I found I could use 1964-1980 Holden six main bearing bolts for the outer rows and 1960-1980 Falcon pre-crossflow six head bolts for the centre rows (they are longer). These all have 11/16" heads and better still have a known recommended torque. They are probably uniquely Australian although the Holden engine looks very much like a Chev 6 and perhaps the Falcon 6 exists in the US.
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Old 05-25-07, 01:33AM   #58
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Default Re: Oakland V8 Discussion

Hugh- I guess Rick must be away from these forums for a little bit- sure he'll be back. I just don't want you to think we aren't paying attention- I, for one, am reading every word. We're very fortunate to have your experience, and your willingness to share your knowledge and ideas.
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Old 05-25-07, 11:26AM   #59
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Default Re: Oakland V8 Discussion

Thanks Jack. Rick mentioned in his last post that he was travelling again.

Can you offer any comments about the pop top piston idea based on your experience with the Kohler.

I may not have made it clear that I am sitting on a project to create a similar car to Ira Vail's 1930 Indy Oakland V8 entry. My friend John who owns the roadster has collected enough bits to build it and we have done some work on it.

I'm very interested in where this thread might lead although we want our car to be one that is period correct but not a replica. Unfortunately that rules out supercharging as it was not allowed at Indy in 1930. I share others reservations about the strength of the main bearing webs and want to restrict extra performance to not too many extra revs. Increasing compression ratio becomes important but not at the expense of making the engine harsh as the 1928-29 Oakland sixes are with the high compression head. Our car will have a pair of Winfields as the Indy car had. Exhaust manifolds with equal length runners were also not around in 1930 but I think we can still see some useful gains with better exhausts than the factory cars had. With better inlets manifolds, a mild cam and some sensible port work, we should be able to get it to go well enough to have some fun. It should only weigh about 2/3 of the roadster too.

Any one found any suitable rods?
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Old 05-26-07, 02:56AM   #60
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Just checked a Pontiac V8 rod, and although they may the same dimensions on journal and big end sizes, they are not nearly wide enough at the big end.
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