4SPEED67

I am looking to rework my SBO heads and I was wondering if I put in larger valves and have them ported opened up does it matter what what casting # I use 4, 5 ,6 or ?. I have casting #4 on a 1967 Oldsmobile 330 and was wondering if I could rework these or should I look for another casting number to do.

cutlassefi

2bbl or 4bbl? You may want to keep the 4's cuz they have smaller combustion chambers than the other small block heads. Otherwise your call.

4SPEED67

It is a 4 barrel. I'm also think of going to an adjustable valve train any thoughts on this

4SPEED67

If I go with a #5 head will I have problems with the rockers because of the difference of the cam angle on the 330 and 350 engines being different? will I have to enlarge the push-rod hole?

olds 307 and 403

I would rework your #4 heads. Unless you want to lower compression or want to leave it running till the other heads are done, why? The early heads other than possible pushrod interference and valve train differences have similar ports. Aren't the 67 330 the normal 39 degree CBA?

4SPEED67

No the 330 is a 45 degree CBA. that's why I was wondering if I would have any geometry problem going with a 350 #5 #6 head that has a 39 degree CBA. If I rework the #4 heads will I have a problem installing them on a 350. I only want to spend money once on a set of heads because I plan on installing a 350 later once the 330 dies or I want to go faster sooner.

edzolz

The 67 330 engines #3 castings were 39 CBA. If yours is 45 then your engine has been changed. What casting number is your block? If it is not a #3 casting, it is not 67.

4SPEED67

I may have misspoken I was told all oldsmobile 330's where 45 cba but digging deeper it looks like the 67 was a 39 cba which would make my life better. We have owned the car since 1970 so no engine change. If I have a 39 cba this will eliminate my need to do a 350 build and will work with the 330 a bit. I will check the casting number to see

edzolz

I am building a 67 330 for a street rod project. Bored .030 with small dish pistons, #4 heads, Edelbrock OL4B, reworked Quadrajet, Lunati cam, and Hedman shorty headers. Mated to a 2004r from an 84 Hurst Olds and an 8.5 inch POSI rear from an 86 442.

cutlassefi

Lose the OL4B. Use just about anything but that, not a good intake.
And what does someone pay for a "reworked" Qjet?

olds 307 and 403

Mark tested the BBO version, not very good. I paid around $300 a couple of years back from Everyday Performance. No plating done but bushing work and and the idle circuits opened up for a bigger cam.

4SPEED67

I have the 394417 block so I believe that its a 39 cba from some research I have done. please let me know if I'm correct. I got this info from some guys in my car club saying that its a different cba but we don't have a lot of Oldsmobiles of my vintage in the club. I believe they now enough to be dangerous.

cutlassefi

Unless it's an original restoration spending $300 for a "reworked" Qjet is a waste of time and money imo.
You can get a Slayer or similar that's waaaay more tunable for the same price. And it'll most likely make more power as well.
Remember, GM didn't put Qjets on any real high performance vehicle they produced. They put Holley's on them. And the new Quick Fuel and Proform carbs for example are further/better engineered Holleys.
I've had multiple Qjets on the dyno in the last 2 years. Not one, not one, had a correct fuel curve start to finish. Even after spending $$$$ having them "reworked". Those are the facts, not my opinion.

83hurstguy

Other than any Pontiac (RAII, RAIV, SD455), Olds W30/31, Buick GSX... yeah GM didn't use them on performance vehicles... and those cars will run with an LS6 Chevelle all day long.

So if you mean "Chevy," sure.

My Q-jet fuel curve looked great on the dyno, to the extent we made zero changes to it. We'll see how it does in the car next spring. They're good carbs in the right hands.

oldsmobiledave

Best to use your #4 heads. As cast they have the smallest cc chambers (64 cc) vs 68-69ccs for the #5 #6 #7 #7a heads.


Also, they are 39 deg bank angle heads.

cutlassefi

Thank you for posting the correct head info.
83- consider yourself fortunate. My customers have spent hundreds and hundreds of dollars on Qjets, with little results.

edzolz

When I said reworked, I meant cleaned and a new kit from a parts house. No extra work for upping performance. I have a good assortment of jets, rods, and hangers to tune it in. And what intake do you recommend for just street driven performance? I'm sure the OL4B will be adequate for no high RPM runs.

cutlassefi

Do you have a wideband? Even a regular Performer would be an improvement.

olds 307 and 403

It was cleaned with an Ultrasonic cleaner and a total overhaul. It is a 1978 800 cfm model. I love that I can adjust part throttle in about 2 minutes. I notched the APT adjustment and added a threaded plug, a little screw driver does the trick. Being an emissions model, the idle was way too lean, so I sent it to an expert.