Engine

The 350 in the car was initially rebuilt by my Dad and one of his co-workers with my attempted help. That build was just a warm-up, still using low compression pistons and the el-cheapo PAW "RV" cam. I was dissatisfied with some aspects of the build, and being ridiculously strong willed I started a downhill slide. I ended up doing two complete rebuilds and several minor refreshes over the next four years, and easily spent enough to do one proper build. I learned a lot, though! It ended up with an UltraDyne 266/272H12 cam (fantastic!), high compression pistons, and a Performer intake. Otherwise pretty stock.

For this build, caution has been thrown to the wind.

I wanted a small block as I like the extra space and the light weight. I also wanted more displacement in order to get a taller cam, but keep good manners. This will be a daily driver in Dallas traffic, after all.

So I settled on the Olds 403. A commonly misunderstood engine. It does have several flaws - windowed mains and siamesed bores - but those bores are huge!

The build dyno'd at 480 ft lbs, 450 hp.

The current build is shaping up as:

403 block w/ J&S Machine 5 main girdle, zero decked

Cometic MLS 0.040" head gaskets

330 forged crank cut 10, stock 350 rods

KB Hypereutectic pistons 24 over

Lunati Voodoo 60803 (227/233@0.050) Lunati hydraulic roller, 235/241@0.050, 0.580")

Olds Performance Products (OPP) 7qt custom pan Moroso stock pan Canton deep pan

Melling high volume oil pump Schumann performance tweaked Melling pump

Cloyes roller timing chain (-0.005" -0.010" chain)

Accel Street Billet distributor

Accel 140009 "Heavy Duty Electronic/CD Type E-core" coil - 0.7 ohm primary resistance, NOT for points!

MSD 6AL-2 box

Edelbrock heads with minor port work and valve unshrouding (remember those huuuuge bores?)

Harland Sharp 5016 rockers

Comp 7131 7981 pushrods

Performer RPM intake, port matched

Early QJet (7042250)

Smitty's new headers built by American Racing Headers

RobbMC mini starter Powermaster 9510 starter (RobbMC didn't clear the headers)

new Powerforce balancer ATI balancer (plan for crank trigger shell, but, well, no)

Flowkooler water pump

Installed cam centerline: 103.5 degrees (106 is the spec for 4deg advanced), installed "straight up"

Had significant pinging, so installed in the retarded position and appeared to hit 110 deg centerline. I don't trust that, though.

Final clearances (measurements in thousandths of an inch unless otherwise noted) (from first assembly....):

thrust: 7

Rod side clearances:

1/2: 9 to 11

3/4: 9 to 10

5/6: 10 to 11

7/8: 10

Rod big ends: 2.1227"

Rod bearing clearances:

1: 2.25

2: 2.1

3: 2.25

4: 2

5: 2

6: 2

7: 2.25

8:2.25

Mains: 2.4978"

Main clearances:

1: 3.5 to 3.6

2: 3.0

3: 3.5 to 4.0

4: 3.0

5: 4.5 to 4.8

Piston size: 4.3723"

Clearance ring gap top ring gap bottom

1: 2.6 to 3.0 31 27

2: 2.5 to 2.75 29 28

3: 2.4 to 3.1 30 30

4: 2.5 to 3.0 29 28 (bore wide at bottom)

5: 2.6 to 3.6 to 2.6 29 26 (bore wide in middle)

6: 2.0 to 3.0 29 28 (bore wide at bottom)

7: 2.5 to 2.0 33 30

8: 2.5 to 3.5 30 26

Odds and ends:

Ignition - I had a terrible time with ignition. This 403 is a strange beast - it likes 24+ degrees timing at idle and total advance close to 40 total (just drive based tuning so far). I had intermittent spark from a Pertronix III dizzy, still had trouble getting the advance right with the Accel. Finally gutted the accel so it's just a trigger. Massive waste of money. The MSD 6AL-2 box does all the timing advance, so I put on a cap-a-dapt and adjustable rotor. Took a few tries to get a good setup, including modifying the Accel pickup mount.

balancers - never would have thought this would be an interesting area, but here it goes. The Dorman balancer is machined too loose - it should be a press fit on the crank snout. The dealership can sell you a new OEM balancer for just over $100 or so. The Powerforce balancer is about the same price, but has nice timing marks on it. Some folks have said the pulley mounting boss on the powerforce wasn't the correct size. It's also sold under several different names which I generally consider a red flag. Then there are lots of SFI options usually starting at $300. The original stock ones are certainly usable, but there's concerns about the outer ring slipping as the rubber degrades, and you'd need a timing tape. I do have a dial-back light, but it'd be nice to cross-check that with markings on the balancer. I double checked my Powerforce and the mounting ring holds onto several stock pulleys perfectly.

I got the ATI balancer for externally balanced Olds with the plan of using their trigger shell for EFI. Well, surprise surprise, the shell doesn't work with externally balanced balancers. Only the internal. Same external diameter....... Well, at least I have a really nice balancer.

Rockers - obviously have to use aftermarket rockers with the Edelbrock heads. The common suggestion is to use the Harland Sharp 5003's, as they are advertised as being for the ebrock head. There's a row going on a ROP about these. Apparently the 5001's are typical Ford parts that "mostly" work. The ebrock head has a taller valve than the stockers, so you need a slightly longer rocker. Guess what? There's another Ford rocker that is slightly longer and "mostly" works - the 5003's. The 5016's, while marketed as just for the Bulldog heads, are actually Olds-specific parts, and work on any of the heads. Supposedly they also have larger bearings. The issue is the Ford ones are designed for a 12deg valve angle, while the Olds has a 6deg, resulting in too much sweep on the valve stem. So I've got some 5016's on order, we'll see what happens.

Here are some references:

ROP: rocker arms

ROP: 3/8"stud Full roller rockers 1.65 ratio? not in 7/16

Lifters - Every company advertises their Pontiac lifters as Olds parts. This apparently is generally OK, although the oil band may pop out of the bore on high lift cams. That's obviously not a concern for me. However, it's getting tough to find quality lifters. There used to be only two US manufacturers - Morel and Johnson. Johnson folded a few years ago, but may be back in business now? So now everything is either Morel or imported. Supposedly Morel does different tweaks to the internals for each customer, but that's hard to verify without wasting a bunch of money. Jury is still out on this one. I don't want Rhoads-style lifters as I'll actually have a little more compression than the cam wants.

Jim at J&S said he has used Lunati lifters for his past several builds, but it's getting very difficult to have predictable results with anyone. His current top recommendation is Isky's anti pump-up SuperLifter - 202-HY. Oddly, that part also cross references to the Chevy, which is supposed to have a quite different oiling setup.

Well, scratch that plan. Those lifters are much taller than the normal Olds lifter and the oil band is much higher. It's also supposed to have a drain-back hole, which mine did not. So no go there.

I switched to the Lunati anti-pump-up lifters. I've also heard folks have had good luck with the cheapo Summit lifters.

Oil pump - I ended up with a stock high volume Melling. Jim at J&S highly recommended Schumann's Dynamic Performance modified Melling pump.

Bearings - I asked about coated bearings on ROP, and one member pointed towards http://www.calicocoatings.com/. Search for "olds 403". Need to call to see what the lead time is. A quick general search makes it sound like ACL makes decent stuff, but Clevites are generally recommended. Not a lot of options for the SBO....

I ended up with all coated Clevite bearings from Calico except for the thrust bearing. See the blog postings for the sob story.

Spark plugs: Looks like the NGK BKR6E, available at AutoZone, are a good starting point. The Edelbock recommendation is Champion RC12YC

Thermostats: The Mr Gasket 4367 is just a regular thermostat now, not the high-performance cup design. Looks like that design is from Robertshaw. The only supplier I can currently find is FlowKooler with the 330-XXX (XXX=temp, like 160, 180, etc) series. But the -180 isn't listed on FlowKooler's page, and Summit lists a restock date in July. Hm. Milodon's is a true Shaw design.

Radiator: Spectra CU161 is a one-row aluminum with plastic tanks, runs around $100. Inlet/outlet are Cutlass-compatible, has the same mountings as a 3 row. Excellent! There was some concern about needing hose adapters, but the Spectra version actually has multi-sized connectors. Just plug 'n play. This is a stock replacement for a wide variety of 70's and 80's cars. Handling capacity is probably not up there with 4 row copper rads, so need to make sure there's plenty of air movement. O'Reilly's Chinese knock-off has identical setup. Even the same part number. Poorer build quality and terrible packaging though.