Projects Unknown Olds Rocket Engine for my 55 Olds Rocket 88 Project

i just want to say that the okies have absolutely nothing on the germans -and believe me when i say this is a compliment !!good job and loved the bbq pics!!thanks,pat

 

What are okies? People from Oklahoma?!

Edit: Alright, checked that on wiki. I hope that in the car culture there is no political offense and we're all the same. Car geeks with too many projects and less money, couldn't resist the next one and only chance to score the next vintage race part or car or what not.

I own the J J Cale record Okie. Cool one though. I'm a record geek also. Hehe

 

Jahns was a popular brand of racing pistons in the fifties and sixties. Today you can get better pistons of more modern material and design. Ross is a company that will make excellent pistons to any spec you desire, for a price. If the pistons are too corroded to use don't be afraid to bore the engine even though it was bored 1/8" oversize already. Have heard of early Olds engines being bored up to 1/4" that is .250 oversize. Maybe the early Olds experts will chime in.

I don't know if there are any piston companies in Germany that do custom orders but it might be cheaper and easier than getting them from the US.

Most economical option would be a single small 4 barrel. If you resist the temptation to floor the gas pedal, a 4 barrel running on the front 2 barrels, can be more economical than a 2 barrel carb.

You will find the mileage more acceptable on long trips. It takes a lot of energy to heat up that big lump of cast iron and stop and go driving is not its forte. But cruising down the highway for hours at 60MPH it can easily get twice as many miles per gallon as it does in traffic.

 

I've heard the same thing on boring the 324. .250 gives a 342 if I remember correctly.

 

I already wrote with Tony about how much you can bore a 303 out. What I remember is that he said 303 up to 324 is not a problem and a save bore. Not sure if it is possible to do more to a 303 in a safe way. Since I hammered the shit out of the bored 1949 303 block while removing the stucked pistons, I will have it cleaned and sonic checked before doing anything to it. If there is enough meat, well then I'm thinking about a 4" bore. But first project will be the 1953 303 in more or less og conditions. Single 4bbl for that one, weiand dual quad for the 1949 303, single 4bbl Edelbrock for the 394 for now.

 

What was the movie, starring Burt Reynolds, where he drove a 4 door 56 Olds that was painted black and gold? He torches and burns the car up the towards the movies end. Would be great to build the car similar, with the black and gold paint scheme. Too bad about the cracks in the caps and heads. I can't imagine trying to find replacements in Europe, let alone here in the States. I am Butch/56sedandelivery.

 

W.W. and the Dixie Dancekings

 

Hey Butch, I have already bought a naked #8 Head from Tony. Cleaned and checked. Wasn‘t cheap to get that one over here but now I have a good set for the 324 Project. The 55 is going to be a patina cruiser. Just cleaning and polishing what is left. New interiour for shure.

 

WW & The Dixie Dancekings

 

Did a bit of tinkering around wirh the blocks, numbers and parts. I measured the bores of the hopped up 303 and the og 303. Hopped up 303 is showing 98 mm (3,85827 Inch).


And the og 303 shows something aroung 95,5 mm (3,759843 inch). Surely does my measurement method has a low accuracy. Just to have some numbers for the blocks.

Here is the intake that came with the bored 303.

And a pic of one of the hard corroded pistons:

 

And i found double springs on the valvetrain of the hopped up 303. Is that original from the factory?



Thats me


And some of our shop space. Was working on that blue little f"""""r swapping the engine the last weekends. It is the new car of my girlfriend and had a lack of oil pressure.



And I tried to measure the rocker ratio of the adjustable rockers.

45,5 mm - 10 mm = 35,5 mm
34,7 mm - 10 mm = 24,7 mm
35,5 mm / 24,7 mm = 1,44

Hmm, if i did the measurements right it is more a 1:1.5 rocker ratio

 

No, your measurements indicate roughly a 1.44 rocker arm ratio. To be exact: it is from center point of the rocker arm shaft to the contact point/pivot point , not straight across ... but as a rough estimate you are on track. Each 0.100" of pushrod lift translates to 0.144" of valve stem travel.

http://performancetrends.com/Definitions/Rocker-Ratio.htm

 

Yeah, sure, since the outer diameter of the shaft is 20 mm I subtracted 10 mm from the other length. But I was hoping to have some rocker arms with a 1:1.8 ratio here.

If those are really Thomas rockers it looks like they fabricated 1:1.5 too.

 

Suggest you bore the minimum to clean up the cylinders. You are right that piston is junk. Valve springs are probably stiffer than stock. I would clean up that intake and use it.

 

the flat wound inner "spring" is a damper, used to reduce harmonic bounce

 

Godsmobile, Great project I also am an old Olds lover (at 78 yrs young). Yrs ago I bored a 303 to 4", used stock1957 pistons.Worked great, no problems. I believe the possible crack in your rear main cap will not be trouble. That 1/4' pin & hole are to hold the cap correctly in the fore & aft position while the cap bolts are tightened. The transmission pictured appears to be a (maybe 1956) Jetaway. If so a 1955 or earlier dual range Hydra will give better performance. The famous B&M racig Hydras were this type. 1956 & newer have larger diameter camshaft journals. This allows higher lift cam lobes to match up with the higher flowing 1956 (#10) heads. Olds made a few adjustable rocker arms & dimpled valve covers for NASCAR. That might be what you have.. The Thomas adj rockers were magnesium, Gothas were cast steel. In maybe 1952 or 53 Olds changed rocker ratio from 1.3 to 1.5. Studebaker rockers are sometimes recommended. I tried them, the geometry was wrong. A dial indicator showed less valve lift than stock 1.5 rockers. The dual valve springs pictured are actually single springs with flat coil harmonic dampeners inside. Your 2-4s Offy manifold appears to be of 360 design. This might give poorer low speed performance& maybe less gas mileage than a 180 manifold. The Rollmaster ( cs7040 ) timing gear set is recommended. It worked ok but I had to remove a lot off the back side of the crank gear to have the 2 gears align. You might contact Tony Ross about this. I might have used the wrong part number. There is a somewhat hidden oil galley plug near the #7 exhaust lifter bore. Make sure it is in place. Have fun. Speedshifter , Greg White

 

the locating pin in the rocker tower is critical, it aligns the rocker shaft with the oil supply hole in the head
as well as the feed holes for all rockers and of course to keep the shaft from walking for and aft.
you have Thomas magnesium rockers,
the plug Greg is referring to is accessed through the back of the block
I have never heard of 1.3:1 ratio rockers in the Olds,
it may just be the luck of the draw but I have found more after market cams ground for the 1.5 rockers than the 1.8

 

Thank you very much guys for all the great info and sharing knowledge with me!!! I would love to bring more light into the history of this engine and it's parts.

Are you with me about my simple measurements and the result that I have a rocker ratio of 1:1.5 there?

Did some of you know more about Oldsmobile itself producing solid lifter valvetrain stuff?

Sounds like the Offy intake does not have so much future in my planned projects.
And yes, it is a 1956 Jetaway. Had it at a machine shop for a full rebuild. I has got a whole rebuild set from autotran.us
Since a lot of money is in it right now, I will work with it for the 55 Rocket 88.

 

Paul, Glad you questioned my rocker ratio figures. I checked the tappet lift versus the valve lift with a dial indicator using stock 1955 rockers & stock Stude rockers . That is the ratio I came up with. I did not test early stock lower lift rockers. Stude rockers definitely had lower valve lift than 1955 rockers. I have Stude rockers & new Cadillac shafts to sell cheap. My Thomas rockers do not have OLDS cast in them. They are the low lift ratio. Speedshifter

 

Another HAMB member wrote me that the valve covers and rockers are factory and off the 57 olds with solid lifters. Did Oldsmobile used to send the J2 with a adjustable valvetrain?
I mean, if Thomas marked their rockers with "Thomas", why should they change that to "Olds".
I'm still hoping that I accidently bought some super rare stuff and maybe it is really something straight from the factory. I read about some experimental performance engines with those numbers on the rods and caps.
Okay, okay, back to reality

What do you guys think about the compression ratio with those dome pistons and #8 heads?

It is so cool trying to line up the history of those engines!

 

As mentioned in the "Rocket Oldsmobile Information compiled"-thread I bought a 1959 371 Rocket a while ago to mount my freshly rebuild 56 Jetaway behind it and put in my 55 Olds project car. Because of the balancing problem I wanted to pull the crank out of it to have it balanced. While doing this I thought, the engine is nearly complete apart now, so why not disassembling it completely to have everything cleaned and checked. Since I had a bit of free time over christmas I was able to work on it a few days in a row.

Pulled it out from the corner of the shop



bleeding











Yummy



Noticed a lot of axial clearance. Maybe because this was a manual trans engine in the past.





Bees nest under the intake



Did scratch my head more than one time doing the disassembly



Broken top piston rings



Pistons and rods



A lot of wear on the main bearing where the axial load of the clutch is going. This is why it had that much of clearance. Not sure if the reason is the manual trans in the past.





Disassembled the last pieces to the bare block



Then I moved onto the heads to get the broken bolts out of it. I managed to weld nuts to the exhaust bolts and got them out this way. Intake was easier to remove.









Plan, for now, is to clean up the engine parts as good as possible, take some measurements and then we will see what has to happen at an engine rebuilders shop. I don't want to get overboard with this rebuild. Planning on doing a big one later.

If you're interested in what is happening to the Olds itself, look here:

https://www.jalopyjournal.com/forum/threads/1955-olds-rocket-88-patina-machina.1139834/

 

I don't know why but I can't see all the embedded pics. The links are ok since I use them for some german forums also. Can all of u see all the pics?

 

Pictures all showing fine here. Cool build, BTW

 

I can see pictures here in Canada. @Godsmobile are you using the app on your phone?

My Olds 324 goes to the shop on Monday for my F100 project. Getting excited!

 

No, I'm not using the app. But I noticed, if I use my mobile phone to have a look on my content here, all the pics show up. Must be a problem of my computer at work.

What will be happening to your 324? Full program on this one?

 

^^^^^ yes Speedy I would like to hear about that also.....

 

Planning on a fairly stock rebuild. It's a 54 motor, I last had it running a few years ago. Plan on swapping on some #10 heads as long as they clean up well enough. Hardened seats, mild cam. The usual stuff. 2 x 4 Weiand intake with two 4GC's.
I plan on driving the truck a fair bit, so drivability is being favoured over performance.

 

I borrowed an electrical grinder from work and ground out all the casting edges of my 1959 371 block before it will go to the machine shop.







Also did those two big holes because they showed similar ugly casting edges



After that, I poked for fairly half of a day all the crap out of the water jackets on each side of the block. What a pain but worth the effort. Look what came out of it. Unbelievable.







If you look across the bore in this angle you are able to see the edge in the cylinder wall at the top end. Pretty sure that the block has to be bored.



I placed it on a pallet to join the other parts and the crank for delivery to the machine shop. I hope this way they are able to store everything from me on there while not working on it.



A few of the new parts already arrived.







I bought two sets of rod bearings from rockauto (std and .010) just to be prepared.

Now onto the crank and checking the options at work for welding and cutting/grinding the thrustsection to standard specs

Currently I'm searching for parts like mains and pistons. Will post a question about that in the olds rocket thread.