Picked up a Oldsmobile 403 W/ extra's now what?

Picked up an Oldsmobile 403 ( haven't got it home yet)

It's pretty grimey, but mostly complete minus the drivers side exhaust manifold. and it turns over, was stored in a shed. includes 2+ extra sets of heads, (not sure if one set even fits it? need to get the numbers off them.

casting on the side is 403 X I have been searching and reading quite a few posts on here about the 403's and they sound like they can be a pretty sweet street engine to have... Just don't have anything to put it in.

I Have a 51 F1 truck thats got me thinking but I already have a nice 49 rebuilt 8cm Merc flathead ready to go in it, soon as the truck is ready...... hmmm 110+ Hp or double or almost triple it? then I'll be swapping the original straight axle out etc etc, where does it end ? lol

the number on the front of the block is 557265 4B so sure it has the windowed main webs.

the Extra's are a Holley Street Dominator Intake 300-16 real clean (hardley even looks used)
and extra distributors one with a new MSD HEI setup in it, plus every other MSD option MSD 6a, timing controler, blaster coil, all new still in the original boxes on and on,
I guess all the MSD stuff could be used pretty much anywhere on multiple applications.

It's really just my time at this point to get the engine and parts home so I can't just leave it. maybe it'll sit in the corner of the shop for a while till I figure out what to do with it...

If anyone has any resources or good rebuild info on these I'd appreciate it. thanks

oh ya and the David Bradley tractor, Thats going in the back yard for more yard art for the wife, Hey Valentines Day is coming up quick!

 

the extra heads are big block (J) i think thats what I see. The odd head is not Olds, Caddy? maybe?
If you run a flat top piston, the big heads would go well, they will drop compression, but have big ports/valves.
A performer RPM small block intake has enough meat to cover the BB ports.
Have fun, Its a cool deal, whatever it lands in.

 

The extra odd head is cadd ,
The 403 was one of my favorite street engines, a few tweaks and they run real strong . ALL 403's are windowed mains .
Street dominator is the best intake for a SB olds, very versitile .
When ya find a home for it we can go over ideas for how to build it to suit the application .

 

Nice engine. It has the largest bore of any Olds V8 ever made (4.351"). There are two schools of thought on builds. One is to use the early 350 heads with small chambers and the stock 403 pistons. This limits you with the small block ports but you can machine the heads for big block Olds valve. The other is to put in flattop pistons and run big block Olds heads (hey, these heads were good on a 400 cu in big block, why not on a 403 small block?). Using BBO heads on an SBO requires porting the intake to match the larger ports. Only a few intakes have enough meat for this. The Performer RPM is one such intake. Also, all small block Olds motors use the same 3.385" stroke, so a forged crank from an early 330 motor drops in.

 

Thanks guys for the info, doesn't suprise me if those extra heads are Cad, there was a few other cadillac parts so just trying to sort through it all to see whats what.


Anyone know what the X is for after the 403 ?? I read a post somewhere on here, the poster states that the X meant that the block had higher nickel content? I've heard all Olds prior to a certain year had this, and had not read anywhere else what the X was for??? any ideas?

thanks again

 

The X is just a casting mark and means nothing. The whole "nickel content" in Olds blocks that's magically traced back to some casting mark on the block is not true.

 

Great find!!!!

 

LOL , stay away from the "old expert" on the left coast .
No need for BB heads unless your blazing high RPM , and you wont be . A lil work on factory heads will do you just fine . The comp cam bolt on roller tip rockert kit is good bang for buck deal , or buy pieces indivually if you want full rollers ( SBF 1.6x 3/8) and 429 ford pushrods to make up differance of the studs and guideplates .
The stock crank will live with 6k rpm shifts . I used to just cross drill them and put good clearence in and studs , but J+S machine has a halo girlde out that would good insurance . DO NOT use a HV pump unless you are useing a 7qt oil pan. Save money , use stock pump, shim spring( holley jet works good for this ) Use a BB pan, gives you extra quart and also has baffle at front of sump SB pan does not have . No need for "oil restrictors" anywhere in a hydraulic cammed street Olds motor .
There are some generic cams that work well in these motors depnding on amount of thump you want. If you feel the need to squeese every last dollar out of your wallet for 5 more hp, get an Engle or lunati Voodoo cam .
If your wallet is to thick I have the coolest Olds valve covers ever produced, I wont sell you them but I will sell you the second coolest set ; p

 

Thanks again for the info and tips.
No the wallets not thick, quite the contrary! but I would love to just do a slightly more than stock rebuild for a sweet driver.
I would love to see some pictures of the Valve covers you have, both sets Please

Oh, for just a slightly modded ie cam and HEI etc. rebuild would headers be a good idea or just stick to the stock manifolds? I read something about problems with headers but maybe that was just for higher compression on the cylinders??



Cheers

Josh

 

If you are a real poverty case you may not have to even break into the long block. You could pull the pan, inspect everything in sight, maybe plastigauge some of the bearings, replace the timing set if it still has the nylon gear, etc. put a cam and valve springs in if you want.


Those olds have a reputation of going many many miles. I've got one SBO here in a beater with close to 300,000 miles on it. Good compression, oil pressure, power and still quiet as a church mouse.

 

And again, why does a 403 move any less air or need any smaller ports than an Olds 400 big block? If anything, the 3.385" stroke of the 403 is more conducive to higher RPM use than the 4.250" stroke on the 68-69 400 motors. Yeah, I'm fully aware of what the bottom end looks like, I've got three of them.

 

you need to find another truck now so you have a place to show off that cool engine ,

 

I'm not real familiar with Olds motors, but did I read in this thread that both the Olds small block AND big block heads will bolt to a 403? That's insane, school me.....

 

This is painting with a broad brush, but,
Only deck height and intake manifold are different, lots of interchangeable parts in the 403, 455, etc.

Of course there are better blocks for x application or heads for y application, but even the 350 diesels have been converted to gas and run hard.

 

Maybe I should find another ford gpw flatfender jeep!!! Make a hell of a crawler . But then again, probably not hmm

 

Regardless of what you have everheard about the 403 with solid main webs, there were never any cast that way. One time a person offered a million dollar reward for any positive proof they existed, never found evidence of even one.

 

http://www.realoldspower.com/phpBB2/index.php

Lots of good 403 info here. Especially look in the "Engine builds/Combos" section. I've learned lots for the 403 build that I'm getting ready to do for an OT Cutlass.

 

It's true if there's a "D" or "DX" on the side of the block. That designates a diesel block and they are reputed to have a higher nickel content. In fact, back in the 80's that block's strength made it the low deck block of choice of high performance Olds engine builders.

Bob

 

Maybe its a religious thing like Malcom X, used to be a 403 now its a ???

As for what to do with it '38 Fiat comes to mind or perhaps an A coupe???

 

yup, I know I'm just reiterating what others have said on here but...

The 403 is pretty revered in the Olds community, as it can be made to run strong with not much effort. The big bore helps make torque production easy, but they're not terribly well suited for high-performance/forced induction/nitrous applications, because of the windowed main webs. Olds started windowing the webs around '73 or '74, so a '72 or earlier Olds block is preferred if you want some serious nut out of your SBO. ALL 403s were windowed, as pointed out.

Olds motors basically are all the same, with only deck height differentiating the big blocks and small blocks, generally. This goes for the '64-up 260/307/330/350/400/403/455 series of motors, nothing earlier, like the 394s or J2s. Those are all a different motor family. Most everything will interchange, including motor mounts, making a 307 to 455 swap a snap in, say, a G-body Cutlass. Heads will interchange, but, as stated before, instake ports will not line up and some headers may not play nice.

Speaking of headers, if you're looking for a good street motor, a lot of guys stick to the manifolds, as finding direct-fit long tube headers for many applications is a bitch. Or, you can look for WZ exhaust manifolds off a late '60s 442, which although they look odd, flow as well as short-tube headers. A couple companies make repops of them.

I've always been told by my Olds mentors that the best way to get a cheap set of good street Small Block Olds heads is to find some #4 heads off a '64-'67 330. These flow very well (the '66-'67 hi-comp 330 was rated at 320hp with 10.25:1 compression), but will flow better with the addition of the big valves from a set of 403 #4a heads. Of course, if you have money to burn, Edelbrock makes good aluminum heads that flow well, or you can find some W-31 heads...those have bigger valves than a 396 chevy (!) but are damn hard to find.

Build an olds motor to have a powerband that's all done by 5500 rpm. They're good at making low-end torque, especially that big-bore 403. Engle makes some fantastic cams for it, as does Lunati. Comp cams aren't reputed to be very well matched to the motors.

If I were to build a 403, I'd find some #4 heads, put bigger valves in with some mild porting, use an Edelbrock Performer intake, a 750 cfm Q-jet, a cam like the Engle 2718H (cam grind EP 18/20, 260/268 adv.,216/226@.050", 112 LSA), a compression ratio of 9:1 with some lightweight cast pistons, a decent non-HV oil pump, headers if you could find them for your application, and an HEI. I would never spin the motor past 6 grand, and enjoy a nice, torquey street motor that will last forever.

 

Thanks for the info, and the links.


Maybe some day I can start to work on my model A?? if it ends up with the hood on it then maybe I could put it in there....

Got the engine home Yesterday, got it on a pallet but had to drag it well over 100' out the shed, made a hard left for 15' and then mostly straight shot to the trailer, thank god for my winch, kids to help operate it , and a few big trees to anchor off of the get the thing going in the right direction....
should have taken some pictures but was on a tight time schedule and took a lot longer than I had planned, came with a nice 10' long 12" tall steel I beam and supports (including the trolley and a nice hoist) that was in the shed, just about ripped my hand off getting it down and apart and out of there!!!! just pulled something in my hand, think it'll be ok in a few days. I hope...

 

Which has nothing to do with a 403...

 

Gee, and for decades we've been told it's the long stroke that makes torque. I guess all those oversquare motors like the Chevy 302 are also torque motors???

1977, actually. All Olds blocks were SMW through the 1976 model year. 1977 saw everything except the diesels go to WMW.

So that must make Dick Miller a DISreputable Olds engine builder:

http://www.popularhotrodding.com/enginemasters/articles/buick/0504em_oldsmobile_engine/index.html

Last time I checked, the 403 IS a small block. Also, the fastest Olds drag cars run DX-based motors, which is WHY they are small blocks.

PEOPLE, I doubt we're talking about a full blown drag car here. For a street driven car, the 403 is a perfectly good motor. Build it, have fun.

 

Y'all have gotten the attention of the ROP crowd and the man who offered the big reward:

http://72.22.90.30/phpBB2/viewtopic.php?t=74308

 

Joe, you're absolutely right. I stand corrected. That'll learn me!

 

dick miller is looking for business

he can't even make headers that fit ,popular hot rodding found that out.

 

And Chris Witt's "million dollars" is as real as the solid main web 403...

For a while he had bumped it up to $2M.

 

The fact remains that we're not talking about a blown 7 sec drag car. We're talking about a street car and the 403 will be just fine. Heck, LS motors have windowed mains too.