Sweet64

Im reaching out to all the olds gurus for some input as to which company's offer cylinder heads for a 1964 330 Cutlass. Looking to start a cylinder head and cam swap in the winter months ahead and thought id reach out on here to get everyone input on my upcoming project, its the original HO 330 with factory auto transmission, compression sitting at 150-155 across the board.Any opinions on cam selection would also be greatly appreciated! No mods have been done to the motor besides manual 600 edelbrock carb, stock highway gears.Thanks for all the advise,have a great weekend everyone!

Fun71

Are you talking aftermarket heads or rebuilt/modified factory iron heads? The only aftermarket heads are designed for big blocks. They will fit on a small block but the combustion chambers would be HUGE compared to your original 330 heads.

Sweet64

Thanks for the heads up Kenneth, ive been told the same thing about big block heads. Im looking for anyone that offers iron heads or aluminium heads for my 330, would like to stay in the 64cc range. It seems to be slim pickens for aftermarket heads. With that said, what heads should a guy be on the hunt for in my situation, i would like to stay in the 64cc ballpark with the best flowing heads for the money, more or less, does a guy rebuild the number 1's that are on it or shoot for another set? Not familiar with flow numbers and what to look out for with olds small block heads, spent years workin with chevy heads so this is a new deal for this guy. Thanks again for your time and opinions.

79T/A

I'm not very familiar with 1's but I do have a set of 2's. I would imagine those factory heads are fairly close to 64cc and probably flow good for factory heads too. You could probably mill them some, do a street/strip port, mild cam and be happy with it.

coppercutlass

Depending on his pistons i wouldnt mill the heads anymore. First pick the piston and so the correct calculations so you dont end up with too much compression for pump gas.

A good set of irons will do ya good. My #6's just have big valves and bowl work under the valves and Those heads so far have been good to power my 355 into the mid 12's in my 72 cutlass. They where cut to 67 cc's .

Depending on how good your cylinders are you could use a std forged 350 piston. in your 330. But if you plan on just doing the swap the biggest thing is to maintain compression will be milling the heads to just maintain it or find a set of shim gasket . Obviously to raise compression you can cut them more but that is all in what your cam choice and usage will be.

joe_padavano

You do realize that your No. 1 heads have the one-year-only shaft rockers, right? Any Olds head bolts up, but you'll need to convert to pedestal rockers, which may mean new pushrods. If nothing else, you'll need to check pushrod length with different heads.

As noted above, what are you hoping to gain? Your stock heads are already in the 64-68 cc range, depending on manufacturing tolerances.

Sweet64

Thanks for replies everyone! Im familiar with the one year only shaft rockers on the 64' # 1's, as far as what im after would be a fresh set of heads, as it comes a time with every old set of heads, mine are due to be done.Before a guy dives into rebuilding these #1's, i wanted to ask the guys on here about what was available on the market, and i wanted around the same cc head as my factory's advertised cc range of 64 cc, give or take a bit, keeping comp ratio close to factory.Then a guys gotta ask if the aftermarket heads dont seem to be available, who's a good supplier of cylinder heads parts, guides,seats,seals,valves ect. For theses # 1's? I've run across these aluminum heads this morning and ill provide the link here, curious what everyones thoughts are on them. They state for 65 snd up, and im,curious, but did any accessory bolt hole locations change from the 64 # 1's to the 65 # 2's..and how about pushrod length and size, will these 3/8 8.700 work just fine? http://www.oldsrocketparts.com/produ...r-top-end-kit/

joe_padavano

Those are ProComps, which are the Chinesium clones of the first-gen E-brock heads. They are designed for the BBO and have BBO-sized chambers. The ad cleverly doesn't mention chamber size.

I suspect they also have the same mechanical fuel pump interference problem on the SBO that the E-brock heads have, since they are clones. If you are interested in the ProComps, get yours from Bernard Mondello. Be sure to run the numbers on your exact piston dish, head gasket compressed height, and actual chamber size, as CR will likely drop noticeably with these.

Sweet64

Thanks Joe, Those Pro Comps dont have a great following with the small block chevy guys that i have talked to over the last few years so this comes as no suprise again, thanks again for your time and replies Joe.

Troys Toy 70

This-

Pro Comps, and I believe E-Brock's, advertise at something between 77-80 CC's, but closer to factory specs at 83-84 CC's any work pushes that up to 87-88 CC's. Ok if your are planning your engine pistons and deck height for compression. Big difference in compression if setting atop a SBO that nothing has been done to it. You may gain slightly better flow, but IMHO couldn't come close to satisfying your loss of compression.

olds 307 and 403

Procomps have been used by quite a few without issue if they are gone through. Olds Rocket Parts due offer them at 64cc. Accesories can be an issue, mechanical fuel pump is a no go and some have had power steering return line interfering with the edge of the head.

Troys Toy 70

It notes them as milled. So to get to 64 from an advertised 77, does this mean that they milled off .060 (1/16) or greater off the bottom of the head? I am not sure on the math, asking for reference purposes?

Sweet64

Good question Troy. Regardless of aftermarket,i think a guy is gonna get my # 1's off and get seats,guides,seals,valves and so forth ordered and rebuild the originals,not a bad deal at the end of the day,but from the research and replies i have gotten around the web,i think ill steer clear of aftermarket cylinder heads for now.

olds 307 and 403

I would consider upgrading to the 2"/1.625" valves especially if new ones are needed. Then get him the open the bowls up as well. If you upgrade the cam, there will be a nice gain.

droptopron

Since nobody has mentioned it, nice looking car. Are you running the Cragars or the Slots?

olds 307 and 403

I agree, nice car.

64Rocket

I would look for factory #5, 6, 7 steel heads. Have 2 inch and 1.62 valves installed. have mill to the CC's you want. take your measurements on how deep in the hole the pistons sit. The head gasket will be .040 thick, unless you MLS steel shim head gaskets at about $100 ea.
With the later heads you will need pedestal mount rockers. I would use the roller tip rockers with poly lock nuts. With poly locks you will need to double valve cover gasket or the thick gaskets from after market.
You should check the timing chain, if it has never been done. If you do I would use a cloys true roller. They have been the most accurate for me.

Gene

In the for sale section there are some factory heads for sale. They are #6 or #7A very good heads.

80 Rocket

I would not entertain any aftermarket aluminum head for a 330 since they are all designed for big blocks. The combustion chamber being too big is one issue, but the bigger issue would be the port size. Even if you milled the head to an actual 64ccs you still have a port way too big for a 330 (or 350 for that matter) unless you plan on making peak HP at 8000+ RPMs.

The best course of action for any small block in the 350 and smaller variety is to utilize the factory iron small block heads. The combustion chamber is within realm as well as smaller ports to keep the velocity up.

I did a set of #7a heads that added 2.5% to the port volume yet had substantial gains in flow (9-16% depending on the lift). What that equates to is a more efficient head. The port velocity is higher than stock, and flows better as well. That adds more torque everywhere in the power band.......and more torque means more HP.

A little tidbit about factory small block heads I have found is this. The #1-#5 heads seem to have the same port configuration, #6-#7a have another, and the #8 heads are even more different. Which one is the best? Well, that depends on application. I think the #8 has the best port configuration (after porting of course) for a strictly street application......unfortunately, the combustion chamber is too damn big for a lot of applications.

The #6-#7a's are a good head for the street/strip guys that plan on winding the engine to 5500-6000rpm range.

The earlier heads would respond well in applications with a lot of cam, compression, and RPMs. That's not to say they wouldn't work in a street application, I'm just saying the others would be more suited for it.

When you look at a #8 and a J head, it is very apparent what Oldsmobile was trying to do and that was to promote a lot of swirl.......and it was 1973 when they came out with these heads, right when the EPA put the hammer down for emissions.

olds 307 and 403

That would explain why anything #8 headed, weather it be multiple 350's or my 403 got good mileage. I also notice Olds love a ton of timing and need it to be efficient, with 8 to 1, easy as much as I can throw at them. My #6 headed 350 gets awful mileage no doubt due to the too small cam for 9.5 to 1 and very lazy timing curve and cold plugs to prevent pinging. A custom cam from Mark will hopefully fix it, allowing more timing, hopefully yield track times in 13's, better mileage and lower octane gas. My #6 heads with bowl/port work, 2"/1.625" valves and dual springs should work great with a GN 5500 rpm governor at the track. I know you have been studying Olds port configurations, glad to hear your feedback. Have you looked the Procomp ports? Supposedly their ports have more velocity than the Edelbrock heads, making them better for the 350. The biggest issue is not having say a 67 cc chamber option out of box, casting overhang not allowing fuel pumps and interfering PS pumps on the SBO.

80 Rocket

I disagree, the biggest issue with ProComps or Edelbrocks for a SBO is the port volume. I have had my hands on both (the old Edelbrock casting, not the new design) and have had them both on the flow bench in stock and ported form. The Edelbrocks are right on what they advertise they are with port volume and combustion chamber volume. The Pro comps are a little off in that regard.

The Pro Comps were slightly smaller than the Edelbrock port (182ccs vs. 188ccs), and flow also suffered a bit because of that in stock form. The better head in my opinion is the Edelbrock in stock form (slightly better).

With all that being said, the 7a head I pocket ported had flow numbers as good or better than a stock pro comp all the way up to .350 valve lift. It was after that that the Pro Comp got better by a slim margin. From .350 lift to .550 lift the Pro Comp was better by 1-5% in terms of flow. After that the Pro Comp was 5-7% better.......but who I running a cam .550 lift or bigger in a street/strip small block anyways?

Here's the kicker........7a head has a 159cc port volume with a 2.00" intake valve. Pro Comp head is 2.07" valve with a 182cc port volume. The Pro Comp is 13% bigger in terms of port volume and 3.5% bigger in terms of valve size, yet the small block head kept pace with it.

What that tells me is the air speed in the small block head will be much higher than the Pro Comp head (and Edelbrock head for that matter). So, even if you could have a combustion chamber size on the aluminum head right where you want it, you are going to have a doggish small block especially down at lower engine speeds where it matters for the street.

olds 307 and 403

That just adds icing to the cake, that makes 3 problems. I have another set of #6 heads with the 2.07" intake valve.They still have the 1.56" exhaust valve and thinking of adding the 1.625" exhaust valve opening the bowls up and tear dropping the guides. Other than the air bumps being ground down already, the ports would basically be stock. After polishing the chambers, to help with detonation and run around 9.6 to 1, would they suck on a 424 ci, 403 based stroker? Thoughts?

80 Rocket

I don't do much of anything to the exhaust ports, they are way to big already. I will clean up any sharp machining edges and do some blending but that is it. I don't even tear drop the guide so it keeps material in place to transfer more heat to the head. Exhaust bumps? Didn't even touch them. I spend the efforts on the intake side for a street type application.

I would go from a 1.56" valve to a 1.625" valve for the simple fact that you need to go oversize to do a somewhat decent valve job on a stock Olds head. The throats are way too big from the factory and need a big valve installed to rectify this.

As far as a small block head being decent on a 424......depends on the application. You are in the zone where you have enough cubes to warrant a big block head but you have a block that wants you to limit your RPMs otherwise you might have an oil pan failure (that's where the oil pan fails at keeping your rods and crank enclosed inside).

I think a small block head would still fit the bill if you intend on making peak power at 5500-6000 RPMs. If you do a good job of porting and can get the velocity up (this is achieved by finding big cfm gains with minimalistic material removal) this thing will make more torque than you would know what to do with. I would surmise the torque band would be broader as well, and the big block heads would be a bit more "peaky". In fact, a big block sized head (especially if ported) will probably raise your RPM band to a place you don't really want to spin it too.

Those 7a heads I mentioned in a previous post made 343hp/377tq on a completely stock bottom end from 1976. I just did a rering and new bearings on a stock short block, added a 221/230 .484 lift flat tappet cam, regular ol Performer intake, those ported 7a heads and these were the results.

That engine has enough power to put a g body in the 12s.

olds 307 and 403

Thanks, I appreciate this info. These #6 heads have a fresh valve job but the bigger exhaust valve and bowls opened make sense. I won't touch the exhaust guide boss. Yeah, even with a Halo, rpm will be limited to around 5500 with the 403 block. I will go with a more aggressive custom and probably a 3000 stall. My 350 has the same 76 bottom end, heads have 55cc chambers, big valves, porting and crossovers filled and will have a 217/223 custom from Mark since this will be a cruiser as. I may run manifolds and duals for a while and maybe move up to 2.5" pipes. Has a 2300 flash stall and will get 3.90 gears behind the 2004R. It should do 13's. What are your thoughts on filled cross over's? Are they worth the effort to fill?

80 Rocket

The more I think about it, the more I think the aftermarket aluminum heads would be better for your 424....and I would say it is because of the atrocious exhaust on a stock head.

In order of what I would use would be:

1. aftermarket aluminum
2. iron small block head
3. iron big block head

The only way an iron head would outperform the aluminum is with lots of epoxy, grinding, welding, and time.

However, if budget is of concern and the #6s are ready to run (or close to it), use those and have fun.

Filling crossovers are okay I suppose. It doesn't show any gains on the flow bench, but using a flow bench to design exhaust ports is a sure fire way to have a port that can flow a lot of air on a flow bench but slow your car down going down the drag strip.

Fill the crossovers if the budget allows. Or, get those plugs from Edelbrock that you grind to fit. That's what I used on the 350 with the ported 7a heads. Made good power without filling.

joe_padavano

If this were a 425 BBO, would you still rank the SBO head above the BBO head? Then why here?

80 Rocket

Damn good question. The assumption is that the iron heads are ported of course.

This is what I would do for the 424 stroker application:

I would port the small block heads and raise the roof to a little under that of a stock big block head. What you will have is a small block head that maintains a smaller cross sectional area than a stock big block head, yet can flow A LOT more air.

I flowed a set of #5 heads that had a lot of porting done to them and they flowed 268cfm. The best iron big block head I have seen on the bench went 281 at very high lift......and a much bigger CSA.

If someone want to hit the easy button, put the big block iron heads on the 424 stroker, or 425 big block (better yet, aluminums). If you want to get some grit in your beer, get the grinder out and work over a set of small block heads. Now, having a mill will save a TON of time raising the roofs. That's probably why everyone sticks with BBO heads because of the time saved.

Working on cast iron is an endeavor for sure. What it really takes is epoxy in the intake runners and being able to weld the exhaust ports to reshape them.

So to answer your question........maybe

olds 307 and 403

I could throw those plugs in, I have a set pounded in #8 heads, so I know what is involved. Would the 1.625" valves out if the #8 heads be OK to use? I have 2 sets to chose from.The #6 heads are fresh rebuilt with 2.07/1.56 valves and supposedly BBC springs. They were milled slightly, one head twice because he nicked the deck. So one head is around 62cc, the other around 64cc according to my measurements. I plan on polishing the chambers to get closer to 68cc, giving me 9.6 to 1 with the current pistons. I need pull valves and see if any bowl work was done to start.

cutlassefi

What you all are forgetting is just putting in those plugs is a band aid at best. In order to get the full benefit you need to fill them. That alleviates the sharing of exhaust pulses among all four center cylinders. That's not a good thing.
And I agree with Joe, I wouldn't think twice about using small block heads on a 424ci anything. Fact is Olds irons don't really flow that great no matter what, unless you have 200hrs worth of work in them. Not worth it imo.

olds 307 and 403

If I didn't have them, paid $400(cost him $1200) for freshly rebuilt heads with the 2.07" intake wouldn't even think about using them. Plus having big valves, I can open up the bowls or finish after a bowl hog is used. I will fill the crossover's myself. Switching to a mechanical fuel pump and I need them milled puts Procomp's from Bernard to 70cc would run around $1500 plus shipping. Then Mark you can work your magic with another custom cam in future.

80 Rocket

I did a bad job explaining myself about filling crossovers. I said if the budget allows, go ahead and do it for the exact reason you mentioned. However, throwing some plugs in there will help a bit with heating up the intake/carb into oblivion so at the very least I recommend that. It sounds like olds307 and 403 is on a bit of a budget so that's why I say that.

My main choice for a 424ci olds engine is Edelbrock/Pro Comp heads. I stated that. However, if a man wants to get a bit intimate with his grinder and cylinder heads, I do believe a small block head would yield great results that he could be proud of when done........assuming he follows some simple airflow principles.

If it was all about airflow, we would put the highest flowing heads on any cubic inch displacement. It is NOT all about airflow, but the QUALITY of airflow.

olds 307 and 403

It also helps, that manners and idle will be out the window on this one. I am dragging my feet on getting my Dakota, getting the cracked magnum heads off, then getting 88 in to pull the 350, cruise control and 2004R out. Then pull the dying TH350 out of 70 and swap in the 2004R with braided cooler lines, speedo gear swap and lock up kit installed. Then I need to swap in the custom cam into the 350, install it in the 70. Then I need to install the 3.90 gears and posi in the Type O in the 70. Then finally the TH350 rebuild and stall and 403 block, buy a girdle and ARP fastners and studs plus machine work including heads along with stripping the 88's interior for racing. God just getting tired writing this, it is on my long list.

76olds

Lord tunderin' geez sounds like you'll be hibernating in the garage all weekend. Just taking the empties back in the spring will be a job in itself haha.
Hope all your plans go as planned .

olds 307 and 403

As always the dollars available affect the final outcome. Thread thoroughly hyjacked, sorry thinking there is good info in this somewhere.