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How good will a 403 do in a FW?

1457 Views 19 Replies 5 Participants Last post by  N0DIH
If this is any idea....

http://www.dragtimes.com/Pontiac-Trans-Am-Timeslip-7272.html

Almost too fast for a 403 with only those mods.... Must be major mods on them....
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Olds 403 would be a near direct swap for Olds 307.... huge power boost, it would be a sweet swap....

.... I have always liked Oldsmobile engines... they seemed to be a bit more advanced/better then Chevy/Pontiac/Buick....
After rebuilding a Toyota (gag) engine and an Olds V8, and a few others (Pontiac 455, 400, 301 Turbo, Iron Duke 2.5L, etc) the Toy and Olds shared higher piston to wall, ring, and bearing clearances. The Olds being 2x higher tolerance than Toy. But with Pontiac, Chevy and the like, the tolerances were pretty sloppy in comparisson.

I haven't messed with an Cad V8 or a Buick V8 to compare.

Olds was like tolerances for bearings in the +/-0.001, and Toy was more like 0.002 to 0.003. Where it is tough to get anything like those special bearings for anything else. I have seen some for Chevy aftermarket, but they are still pretty limited.

Yup, a 403 would be a great shot in the arm. Even the 350 is a great swap. I did a 350 in my Cutlass to replace a broken 307 (my fault, screw, carb, open 4BBL's, #7, hole in piston..... owch.) and was very pleased.
G
Oh boy!. Stock Pistons, stock rods, stock quadrajet, stock plugs, stock th350, stock flywheel, stock shifter, stock 3.23 gears and he runs pump gas and Tiger Paw street tires. He's even running cats!

So a 403 with a performer rpm cam/intake, slightly modified stockish heads, and headers/w dual exhaust and a stall converter will get a 403 running 10s?

High 13's on its best day!
Well honestly, the stock rods, pistons, Q-Jet, plugs, THM350, etc all do fine for making a good race motor, as there isn't much aftermarket for the Olds V8 that isn't high $$. As long as they aren't abused, they will live. I have seen numerous occaisions that the Pontiac 455's run stock cast (nodular iron) cranks deep into the 9's, and for a long time too. Cast is stiffer and makes more power due to less bending. But when bending gets too far, bang! Its all over.

You can mod the Q-Jet to no end, it is still 800 CFM stock (nearly all, if not all were 800's after 1976, just some restricted secondary air valve to limit airflow. THM350 stock? It uses less HP than the THM400. But it won't live long stock! But is good to 8's and faster moded. Stock shifter is darn good. HEI? Good for anything you want up to 7500 rpm or so with AC Delco module.

Olds 350 "5" heads are good heads, and there is plenty there to port of you know what you are doing. Can they support 10's? Hmm....

Now, tiger paw 245's? No frigging way for 10's! I agree, 13's tops is more in line. This is likely a bogus post or he is intentionally trying to mislead.

With the speeds in with 0's at the end, is either a computer program or just made up. You won't get that many 0's at the end.

And we must remember, 403's are NOT SAFE to rev over 5500 rpm. They all are hollow main webs (as were all Olds from 77-up except diesels) and are weak bottom ends.
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You can comment on the timeslip, I did. Go for it!
Night Wolf said:
I have always liked Oldsmobile engines... they seemed to be a bit more advanced/better then Chevy/Pontiac/Buick....
How so?
Tighter Tolerances. Most reliable GM engines till it died off. Had bigger pistons compared similar size GM engines for better breathing. They often made as good as or better power per CID with a smaller cam than the other GM (or even Ford/Dodge) brethern. Olds Pioneered roller cams in GM. They had 6in rods from the git go, Chevy only did it aftermarket (Pontiac was 6.625"). Chevy guys used to love to steal Olds SB rods for SBC's. Port designs were actually quite good, as Mondello designed many of them. But emissions killed them later. Remember all out power isn't the goal, efficiency is. Olds had the strongest block, best bore/stroke ratio, best rod/stroke ratio, strongest 2 bolt bottom end, etc. Hence why the Olds design was chosen to go diesel. Olds pioneered the ECM timing controls and EFI on the SB V8. Often the Toronado was the test bed. Olds pioneered FWD in GM.

The 350 peaked with the Ram Rod 350 and W31 350 with some killer power. It took Chevy a lot more work to make a comparable 350. The 307 made 180 hp in HO trim. More than the 350 (170hp) ever did from 1975-up. And met stricter emissions requirements doing it.

Yeah, Olds did some great things for GM Engine Development. I am sure there are tons more.
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Ah gosh, N0DIH hit is all right on the head! damn... thats good :)

Yeah, pretty much all Oldsmobile engines are packing more power then other GM's (not counting Cadillac... they didn't follow the tradiation) Even the HO 307 I like to pick on so much... was making 180hp/275ft-lbs torque or so in the mid 80's... which was a crappy time for performance... thats right up there with a Ford 5.0... of course the HO is somewhat rare... used in the Cutlass 442.... but it was there.

Old's engines were among the best IMO...

Oldsmobile also made the Quad4, which was the main pioneer for all of GM's high hp/high RPM DOHC I4's, not to mention nearly everyone else...

Oldsmobile also started development with the Quad8, which was to be made into the..... Northstar :) but GM didn't give Olds enough development money, so instead of killing it off, Cadillac took over, and then made the Northstar...

but remember, it was the Aurora (Olds) that was the *only* car to get the 4.0 Northstar... and the Intruige (Olds) that was the *only* car to get the 3.5L V6 "Shortstar"... bascially a Northstar with 2 cylinders chopped off....

The Aurora also paved the way for '98+ Seville and '00+ DeVille as well as most other future (now current) GM cars...

...you see, even in its final years, Oldsmobile was still doing sooo much for GM.... then GM kills them off....WTF....

ok... tangent... back to engines...

yeah, I stick by Olds... and when talking the ranges of 300/350/400/450, the Olds, IMO was always ahead.... lacking in the aftermarket obvisouly, because someone is more inclined to modify their 1975 Camaro then a 1975 Delta 88, yes... but stock for stock, the Olds was ahead of most all of GM, and even Ford and Dodge in some cases.

Oldsmobile was also first to use a fully automatic transmission... they invented the Hydramatic in 1941 IIRC? yeah.... Cadillac may have been the first to have alot of advancements and features on the car chassis and within the car... but it was Oldsmobile that was leading the engine development and performance standards.... Rocket 350, Rocket 455 etc... niiiice....
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Wow a Quad 8...That sounds badass :cool2:

Interesting stuff to know

Do you think that GM should have cut Buick instead of Oldsmobile?
I forgot on the hydromatic, but yes, Olds pioneered a lot.

Each car division at GM has areas (well, used to) that they did the chief development work in. Buick, Turbo (but Olds started it in 1960 with the Turbo 215 aluminum V8, which was the 215/300 was a "Oldsmobuick" as they did joint dev on it), Pontiac, heads/airflow, etc. I see a lot of Pontiac's work on the LT1, which makes sense for its good low end power and torque from a Chevy.

Oh, Pontiac came up with Reverse Cooling in 1955 in production.
G
Hey I'm all for Olds power. My argument was that the T/A with that 403 had no chance in hell to run 10's. Check out a couple of my older Oldsmobiles, black '66 had stock '70 455 while the candy burgandy 67 had a '70 468 Olds with many mods (both came with 330's stock).
Nice! I agree, it would take a LOT to run 10's with a 403, and keeping within the 5500 rpm rev limit, I would have to say impossible. That 78 T/A's are 3800 lb cars, no lightweights. So I do agree.

Now, a 455, with major work, yes. But a lot of work and a lightened car. or power adders like Turbos's, nitrous and/or superchargers (maybe "rocket" assist?)
I~LUV~Caddys8792 said:
Wow a Quad 8...That sounds badass :cool2:

Interesting stuff to know

Do you think that GM should have cut Buick instead of Oldsmobile?
32v DOHC, yup.... I have heard the Quad8 is actually the Northstar in its raw form... then I have heard it isn't... but either way, the Quad8 paved the way for GM's DOHC V8's... as well as the other guys... much like the Quad4 did for the 4bangers...

between Buick or Oldsmobile? My personal opinion would be yeah... Buick, besides a few rare casses hs never wowed me or went above and beyond... ok, maybe more then a "few" but in compairison to other GM's (main) divsions, to me, it isn't among the best.... then again I don't believe Buick nor Oldsmobile should have went.... same goes for Pontiac, Chevy and Cadillac....
N0DIH said:
I forgot on the hydromatic, but yes, Olds pioneered a lot.

Each car division at GM has areas (well, used to) that they did the chief development work in. Buick, Turbo (but Olds started it in 1960 with the Turbo 215 aluminum V8, which was the 215/300 was a "Oldsmobuick" as they did joint dev on it), Pontiac, heads/airflow, etc. I see a lot of Pontiac's work on the LT1, which makes sense for its good low end power and torque from a Chevy.

Oh, Pontiac came up with Reverse Cooling in 1955 in production.
Wow, can you post some information on the Turbo 215? I would love to learn about that!

What has Buick done AFA turbo? only thing that comes to mind is the Grand National where the turbo'ed their 3.8 V6.... and got insane results.... then later, not turbo, but super charged... with their 3800 V6 starting with the Seires I.

I agree about the Pontiac statements... They liked the airflow part so much that they even did more besides the engine to gain better air flow..... such as.... RAM-AIR :) It seems like when Pontiac got a version of a GM engine or which ever the case, they always tweaked it a little more then the others... example would be the Firebird/Camaro... I have heard in most casses a Firebird would be faster then a Camaro (all else being equal) simply from some fine tuning and such... numbers may be the same, but its there. How much, I don't know... just something I heard.

Those Oldsmobiles are soo nice...

my all time favorite muscle car, though rare, is a 1970 Cutlass 442 W30.... I would love to own any '70/'71 Cutlass to satisfy my muscle car craving... tho I am not too big on muscles cars in general... '67 GTO, '69 Camaro, '70 Chevelle SS, and ~'70 Skylark, are among my favorite... I much prefer stock, or stock looking cars then highly modified... they just don't do much for me....
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N0DIH said:
If this is any idea....

http://www.dragtimes.com/Pontiac-Trans-Am-Timeslip-7272.html

Almost too fast for a 403 with only those mods.... Must be major mods on them....
Nothing new. People B.S.ing about 1/4 mile times. If it ever does run that kind of time it won't be very streetable.
10's seems rather unlikely... Unless he's using a confused Gtech...
If you ever saw the bottom end of a 403, you wouldn't question it... But then again, The LS2 has a bottom end simillar....
It's not the strength of the motor, it's the lack of mods. From what I saw, it looked like 20-50 horses pulled from that engine. Not enough to push it into the 500+ horse and torque it'd take to make a 3800 lb car run 10's...
Agreed. You can be deceptive and call it stock, as far as I'm concerned, that is just saying it came on the car, I would (if I was being deceptive) say my carb and distributor is stock, depsite the fact that I modified them.

A Q-Jet, HEI, can both support 700 hp just fine. But not as GM delivered (well, HEI maybe, but not Q-Jet). You can say the cam is stock, stock for what? a 400 hp W34 cam for a Toro GT 455 reground? Ok, there is something "stock" about it, but not stock as GM delivered to you.

Like an friend of mine and I were talking tonight, he modifed an intake for a guy, running a "stock" peanut port 454 intake on a 502, calling it a stock 396 and painting it orange or black. In reality it is a highly modified dual plane intake that flows like a stock rectangular port intake from an L88... Well, it was stock on SOMETHING..... Was even in stock at Edelbrock before I bought it....yeah, we can do that one too!
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