My1st olds69"S"

I have a 69 cutlass S with a 403 engine in it.. Right now I cant afford to put in the engine I want. Is there anything I can do to the 403 to make it a little meaner. Any suggestions???

joe_padavano

The 403 responds to the same upgrades as a 350, it just has 15% more displacement. If the 403 is stock, then it will respond to the usual intake, carb, and ignition upgrades. More involved upgrades would be a cam and heads (to increase compression and valve size).

brownbomber77

$600 can get ya early heads, a good cam/lifter set, and a used intake/ long tube headers...and another 75 horse from stock...as well as a broader power band from idle to redline

88Deltakid

how early should the heads be?

brownbomber77

1972 and earlier, 4, 5, 6, or 7. Nothing with an "a" in front of it except 5A from the 80's. Those are the small combustion chamber heads. 5 "flow the best" but Old's heads flow within like 8% of each other or something. Nothing that is going to matter until 5000RPM and you shouldn't be hanging out that high that long with a 403 anyway.

captjim

That post is both confusing and incorrect. 350 heads from 69-70 were #5, 70 were #6, 71 were #7, and 72 were #7a. All are fine and have very similar combustion chambers and flow. All will raise the cr a point or so. They will also need to be drilled to accept the 1/2" head bolts, no biggie.

Not all all sure what you mean about the
"Nothing with an "a" in front of it except 5A from the 80's."
coment?? Olds had 7a (little A) and 3A heads (those ate late 70's 350 heads, not a great option), 4A 403 heads, 5A, 6A, and 7A 307 heads. The only head that is a good option is the 72 350 7a head.

captjim

I disagree with just about every word of this.

380 Racer

x2

brownbomber77

I was saying exactly what you said, except I forgot about the 7a "(little a) head. So, the others with A, have big combustion chambers. My mistake on the head bolts. I took a 5 year haitus from Olds stuff. Enlighten me on which part(s) is (are) incorrect.

captjim

Decent cam/lifter kit, $300 at least. That leaves $300 for heads, headers and gaskets? Not realistic, IMO.

No way you are picking up 75 HP with worn out stock heads, IMO. Good valve job with a little port work, sure.

Power band will be broader, but it will move up.

IMO both of your posts were misleading and not realistic. Again, just my opinion. The 2 flaws in the 403 are compression and cam. Bolting on older 350 heads that are fresh and well done and a good cam will absolutely wake that engine up, providing it is in decent condition. However (and this is a long-running issue that I have), it is not going to happen using worn out junk.

captjim

IMO, you did not say it very clearly.
"So, the others with A, have big combustion chambers"
Again, not correct. Olds 307 heads have a large A, 5A, 6A, and 7A but have small combustion chambers. The 77-80 350 3A head has larger chambers than the early heads, 77cc +/-, but that is still less than the 73-76 350 #8 head and the 403 4A head.

brownbomber77

Maybe my dealings with Ford stuff have misplaced my reality of the cost of Olds stuff....and inflation, too...maybe. My bad...a Ford flat tappet can be had for less than $150 with lifters, so unfortunately, I have been outta the game just a little too long.

captjim

You can still get an old generic 214/224 cam pretty cheap, but not a decent one.

brownbomber77

Well...define "decent", I'm not sure how you guys feel about Edelbroke stuff, but I've never had a problem with it. They make a cam and lifter set for $180 at the 214/224 duration. For the daily driver use with a little more oomph, how much money can you spend, speed costs money, how fast do you want to go?

brownbomber77

There's no one thing you can do that will make it go fast...

captjim

It is like anything else, you get what you pay for. Those cams are serviceable, but there are MUCH better choices for a little bit more money. What about springs? IMO it is all about the combination and attention to details.

88Deltakid

No disrespect to anyone here & I guess it's just a little ignorance on my part, but I here alot of input placed on what you should go with and what not to go with. Idea was brought to me was swapping it out for a big block 455. Only problem with that is I can't find one in this are let alone within driving distance of a few hours(not to add nothing to haul it in). Myself on a budget of $3k give or take a little it's either rebuild my 403 with late 70's 35o heads or go crate GM engine. I really want to keep it Olds thru and thru. I guess what i'm saying is part numbers would be helpfull. Iam not looking to have a full out drag car but will be puttin it on the track for s#its and giggles. Not a dailly driver just a show and weekend driver.

captjim

You should probably start a new thread. That said, KB made pistons just for guys like you to be able to bump Cr up into the high 9.xx to 1 and use your 4A heads. So, if you are going to rebuild it, that changes everything.

olds 307 and 403

Get the KB, Arias or Diamond pistons. Get matched cam, lifters and valve springs to match the compression ratio. Either your stock heads with porting or Pro Comp or Edelbrock heads. The Pro Comp or Edelbrock heads flow much better. After porting your 4A heads, might not cost any more. You will be at around 10 to 1 with the aluminum heads. With the right cam and their better chambers, pump gas is possible. Headers also should be added, SBO manifolds are awful.

captjim

That is a good plan. However, his stated budget is $3,000 which is not realistic. Same issue I have been talking about for years. You simply can not build a quality street engine using new parts for that price.

88Deltakid

I understand items cost money but as I stated before, whatever items I can find through O'reillys I will not pay full price for parts I caqn get thru their. What manifolds are suggested?

67442HT

I really like the 403 due to it's relatively large bore and short stroke. It can be made into a real nice street "Hot Rod"

brownbomber77

I don't know how good of a job Professional Products did on their Olds intakes, but if you're looking for new, I thought Edelbrock was the only company who still made aluminum intakes for Olds.

olds 307 and 403

Jim, your right, $3000 is too little for a proper build. I figuring $2500+ just to add Edelbrock heads next year. The RPM intake is good for a hot 403. Sanderson makes shorty headers with plenty of clearance and good quality. Even $5000 is going to be tight, top to bottom with used stroker pistons and rods on my 403.

409sleepr

I have a Olds 403 its a good engine, like all of the others were saying cam,heads,intake etc. will help... I put 350 heads on my 403 but it gets hot on cruse nite, changing out head gaskets this weekend. I have read some where that you need to drill coolant holes in them but don't know anyone who as done this yet, I only have about 1k miles on the 350 head swap. anyone know any tricks or where to drill the coolant holes?
any help would be greatly appreciated

olds 307 and 403

Your cooling system needs a big rad, heavy duty water pump, high flow thermostat, good 6 or 7 blade fan with a good clutch and shroud. Also high output electric fans will also work well, I have Dodge Stratus fans. I had endless cooling issues with my 403.

My1st olds69"S"

My 403 has been sitting for about 7 years and needs a major tune up. Any suggestions on plugs and plug wires to get. I had my olds out yesterday, everytime I give it gas it would quit on me??

409sleepr

thank you for the feed back, I don't have a shroud on it yet cant believe how much they get for them

409sleepr

how much money do you really want to spend? you may be able to just get some ignition parts(IE)cap, rotor, points? wires and plugs and run. But its been sitting a long time so there could be several things wrong with it . most of the time its two things that stop or make a car run poorly, they are fuel system and ignition. I would get a book first. however from what you have said it sounds like it may be your fuel system / carburetor. get a rebuild kit or take it in for a good cleaning. snip off the ends of any vacuum hoses and or replace as needed. replace all fluids gas ,oil, trans, coolant ,belts fuel and air filter so on and so forth. it takes money and time to play with this stuff. PLUGS AC DELCO R46 or R45 are stock
hope this helps.

409sleepr

go to library check out their books for your year, go online you can get all kinds of info for tune ups and parts good luck

coppercutlass

For the record i have a sbo that runs low 13's might do 12's this year and i have 3k give or take mainly give . Knowing people helps get out there ask racers for used parts . Taking risk's is also part of the budget builds. Im not saying do unsafe stuff but ! im close to 400 hp for the 3k budget but most will snarl their nose at my set up and say its junk . It might be but it ran 13.3's with a small carb and too tight of a converter. I just thought id put a diffrent spin on things. I dont look to what i can do with more but how much can i do with less and keep it safe and reliable.

409sleepr

nice car. my car is not close to being that fast, but I have never taken to the strip. it would be fun to do once to see what it would do. I just take my car out and have some fun with it when i'm not working. I have been working on it for over five years . as money and time allows budget builds take time and it does help to have friends out there that have extra parts. keep up the hard work you will get there

captjim

All due respect "Taking risks" has no place in a quality rebuild. This is a peeve of mine. Yeah, you can scrounge parts and do things half-azzed, and brag about. Then the next guy thinks he can build a reliable 400 HP engine for $2800. So, If I found a guy who was tired of a project and had all the components to build a 468 and he sold it all to me for a grand, would it be accurrate of me to say, "Sure, you can build a 468 BBO for a thousand bucks"?

coppercutlass

You take risk's no matter what. Guys are running 40 plus year old cranks at high rpm. They can fail. I cut no corners on mine. Nothing was half @$$ed . The only thing was price. My engine has 35 passes on it I can drive it pretty much anywhere . If it was hacked as bad as you say I think it wouldn't have survived . I mean what if you have a 403 that you can polish the mains your self measure and make sure you can keep standard bearings Then get a good set of heads that will jusr need a simple clean up and new seals, How is this hacked. My first engine was built like this polished rod and mains with crocus cloth and shoe string the the cylinders where honed, new rings bearing and oil pump cam etc. and the heads where just freshened up. It was a high 13 sec motor with under 2500 in it. It now sits in my dads car it has roughly 10k miles on it and runs strong no noises no smoke just dead reliable How is this wrong. Anything i do is measured to make sure it is still useable clenliness is key as well how is there no quality there just because is low budget and built with used parts does not mean it cant be good. My current short block is 72 block with 72 crank with a combo 70 and 71 rods for roundness picked the best ones , 1968 hi comp cast flat tops that where bought used. everything was checked, polished, honed cleanded up and put together . If you have good parts to start with then less needs to be replaced I feel that for what i do my stuff works just fine . Btw yes if you find a guy with good parts or down on his luck and you get to build this screaming deal 468 then yeah its a budget build it's all part of the game finding parts swap meets etc. in budget build time is your friend and knowing guys with good parts and race cars helps too. In my builds i also sell my old parts to offset new cost and total up the total bill when i first got my engine done it was 2800 now its a little over 3k but i went to a new carb and converter and sold the old one to offset cost's.

jag1886

I think you guys are a little off the subject, the guy asked for advice on things to make his car go better on the cheap.
I would just concentrate on getting what you have running as good as it can, tune it up, change all the filters, maybe freshen up the carburetor, change the fluids, make certain things are hooked up properly, after that I would work on a better exhaust and a better air cleaner. It may not be much faster but you will have the piece of mind that it will get there and back.

My1st olds69"S"

Thanks alot man, that makes alot more since to me..Keep it simple

Troys Toy 70

My 70 Cutlass has a 403 & #8 heads, bought it that way, so I don't know what was some to it. It has an Elderbrock intake and a holly carb. Nice motor to tool around in. It does like to heat up in stop and go traffic.

For you guys that have a 403 in a 68-72. How much clearence is there between the oil pan and frame? mine has none.

Lee_A

My step-brother had a '65 F-85, and a 330 with a blown head gasket. 3.08 rear gears, non-posi. I gave him the 14" rally wheels off of my 72 Cutlass convertible, along with the stock intake from my 350 and a junkyard Q-jet.

We got a junkyard 403. Pulled the 330's heads, ground out the bump in the exhaust, a buddy at the local machine shop enlarged the bowls and installed the 403's valves, a proper set of valvesprings and enlarged the bolt holes to fit the 403's bolts. Installed an old single-pattern CompCam Magnum 270 cam. We used whatever was the cheapest adjustable valvetrain option at the time, but NOTHING was roller!

We THOUGHT we were going to put headers on it, a local speed shop had 2 sets of SBO headers, and let us take them home to test fit. We got one header on (think it was the passenger side), but couldn't get anything to fit the other side. The car was his daily driver and we had to get it road-worthy - so we took it to the muffler shop with one header installed and the stock exhaust manifold on the other side, just "temporary" until we got a header modified to fit the other side (never did).

With 235/60-14 cheap radials on the steel wheels, the non-posi 3.08 gears, iron intake, the one-header/one-manifold exhaust, and the single-pattern cam, he ran 13.8's.

PLUG WIRES: My favorite are the Moroso BlueMax wires (you can now get them in other colors, too). Accell 300+ are also good. The ONLY bad wires I've ever bought were MSD's - I've seen 3 sets that had an internal break (which I found each time bu measuring the ohms/inch before installation)

SPARK PLUGS: Keep it simple, AVOID the "trick" (E3, SplitFire, exotic-metal high-$$) plugs. Plain old copper-core is tough to beat. I like NGK's, but use Autolites with great success in Pontiacs.

SUGGESTIONS: Make changes that can be used with your "dream motor" - such as exhaust. Even if you dream motor is not an Olds (I won't tell, if it is ) you'll still need a good exhaust system/mufflers. Most headers have 3" outlet, so I'd go with 3" into a 3" "X" back to 3" inlet/outlet mufflers. From there you can go with 2.5" tailpipes to make fitment a little easier. The 403 will like a set of headers, if you can fit those into the budget.

- Gears/posi/sticky tires: Horsepower is useless, unless you can put it to the ground. You'll need these for any motor.

- If you are staying Olds, then get a good torque converter, at least 2500, maybe 3000 or so. I had an old '67 Firebird with a 326 Pontiac and a cam that was too big (installed by previous owner) - it ran mid-16's with a stock torque converter, and high-14's with a 2800 stall.

Good luck,
Lee