TheSamba.com :: View topic - Question about some 041 heads I came across...

Thu Mar 29, 2018 7:44 am

I recently came across a set of 041 heads new in box with CB Performance initials stamped on them.Also a new Demello counter weighted crank,CB Super Rods,Cima 94s,and a few other things.All of these parts were bought new by a friend of mine in the early 90s I do believe.I am thinking of building a 1915 for my Bug.Is there anything that can be done to make the heads usable?I have seen a lot of negatives regarding these heads.Are they all true?Thanks for your help guys.

Thu Mar 29, 2018 7:47 am

Send them off to someone to be ported and have a valve job and get the valve size you want.

Thu Mar 29, 2018 7:52 am

74 Thing wrote: Send them off to someone to be ported and have a valve job and get the valve size you want.

That would be almost the same price as buying a new set of heads.

Hand porting, seat changes, new valves, valve job......why waste your time and effort?

Thu Mar 29, 2018 8:44 am

Can you post some pictures of the heads?

Thu Mar 29, 2018 8:51 am

I will take some pics when I get home.Thanks

Thu Mar 29, 2018 9:19 am

I built a 1776 with 041 heads. I ported them myself and gave them a 6 angle valve job. 110 cam, 9:1 compression, single 44 Weber. It rocked for autocross, tons of torque and pulled to 6K easy.

brad

Thu Mar 29, 2018 9:45 am

There's nothing wrong with the 39x32 valve combination. It's the PORTS that need correcting to achieve the correct INT/EX flow ratio. A 32mm exhaust valve can flow enough to support 200HP. The stock tulip valve may be a restriction though. I bet if you send them to username Brian_e he can correct the issues with the heads.

Thu Mar 29, 2018 10:57 am

bugguy1967 wrote: There's nothing wrong with the 39x32 valve combination. It's the PORTS that need correcting to achieve the correct INT/EX flow ratio. A 32mm exhaust valve can flow enough to support 200HP. The stock tulip valve may be a restriction though. I bet if you send them to username Brian_e he can correct the issues with the heads.

Haha, I just did a real quick rework on a set low mile 041's a few weeks ago. Certainly not ideal, but they came out OK. Biggest problem is the large port volume from the start. I kept the 39x32's. I didn't get real carried away because the ports are already big, mostly in the wrong spots. I did a quick bowl blend, a little work around the guide and about the same thing with the exhaust. After the valve job I think I ended up right at 155cfm at .450", and about 118 on the exhaust. I think they had a 67cc's when I was done, and were around 250fps average (kinda slow).

For comparison, I finished a set of 37x32 Mexican 043's to 158cfm at .450 and 275fps with a 63cc port with a little more time, but they will end up a way better head.

The 041's could probably come out pretty good with 42x37 valves installed. Then the port volume might start working out, but at that point you are way better off with new different heads.

I will be test driving the 041's on a 2054cc, C35, 9.1:1, 40 IDF's toward the end of next week. I can let you know how they do.

For your 1915cc I would suggest either Roy's 37x32, or a set of Tim's ported 37x32 heads, a Web 163 cam w/1.3 rockers, 40IDF's, and an 1 1/2" header. If the 041's are new, put them in the classifieds. Some old NOS parts hound will snatch them up.

Thu Mar 29, 2018 1:22 pm

Here they are.They are actually from the early 2000s.I don't seem to have any concept of time the older I get.They look grungy,but that is just 20 year old cosmoline.Any insight appreciated.I have no trouble buying heads,just want some opinions on these.Was CB selling shitty heads?

Thu Mar 29, 2018 2:02 pm

Those are 39 x 35 valves.
Even without valve removal you can relatively easy make them so they will support a solid 125 hp..
I'd suggest a web 163 advanced 2 degrees along with 9-1 cr
Yes the port volume is a little high, but if you do it this way you will not notice it
On a side note, I have never seen a 32 mm exhaust valve support 200 hp unless the engine was turbocharged.

Thu Mar 29, 2018 2:19 pm

I actually like the GO3 head better than the VW 041. Bigger exhaust valve (not sure on the seat though) and best of all they use the small diameter long reach spark plug so are not as crack prone like the VW head with 14mm plug.

Casting flash is usually an issue so make sure you clear/drill it out to keep the heads as cool as possible

Thu Mar 29, 2018 3:06 pm

I would take them apart, check the valve job and if those are aluminum retainers, throw them out. Also make sure they are HD springs, not stock. CC the chambers. The seats appear to be the correct size.

Thu Mar 29, 2018 3:37 pm

Thanks for the help guys.Yes they are aluminum retainers,so they will go if I use them.As far as casting flash,these are extremely clean.I just put a motor together with the new Empi head(don't hate),and the flash is night and day better than they are.The problems I seem to remember people bitching about was they cant be made to not run hot.I have never assembled anything but stock motors,so I am in the dark here.Can I have a reliable daily driver 1915 with these?Was thinking dual 40s?Would these be better if I add some stroke?

Thu Mar 29, 2018 6:58 pm

Alstrup wrote: Those are 39 x 35 valves.
Even without valve removal you can relatively easy make them so they will support a solid 125 hp..
I'd suggest a web 163 advanced 2 degrees along with 9-1 cr
Yes the port volume is a little high, but if you do it this way you will not notice it
On a side note, I have never seen a 32 mm exhaust valve support 200 hp unless the engine was turbocharged.

Johannes' 1600 rally engines regularly use 39 or 40 intakes and 32mm exhausts. He says that 35 exhausts aren't needed for a 40mm intake. His heads usually flow 180-200 CFM at 25" depending on application. I had an in-depth discussion about heads.

Thu Mar 29, 2018 7:21 pm

I have a new set of those that were opened for 94s and they cc'd at 58 I think.

Fri Mar 30, 2018 12:50 am

bugguy1967 wrote:
Johannes' 1600 rally engines regularly use 39 or 40 intakes and 32mm exhausts. He says that 35 exhausts aren't needed for a 40mm intake. His heads usually flow 180-200 CFM at 25" depending on application. I had an in-depth discussion about heads.
The reason to why only 32 mm exhaust valves are used in the rally class is specifications. The rule book does not allow larger than stock exh valves. Those rally engines typically produce 160-165 hp.

T

Fri Mar 30, 2018 7:14 am

So,good head or bad head for a 1915?Compression,cam,and carb/exhaust recommendations?My wife and I drive this car daily.A couple of 3 or 4 hour trips a summer.73 Standard Bug,stock gearing,slightly taller rear tires.Not looking for a screamer,just a good tourquey motor probably never see 5000rpm.

Fri Mar 30, 2018 7:17 am

Alstrup
Thanks for your info.Just wanted to ask again now that I have laid out what I am looking for.Just a reliable cruiser.Thanks

Fri Mar 30, 2018 7:20 am

Alstrup wrote: Those are 39 x 35 valves.
Even without valve removal you can relatively easy make them so they will support a solid 125 hp..
I'd suggest a web 163 advanced 2 degrees along with 9-1 cr
Yes the port volume is a little high, but if you do it this way you will not notice it
On a side note, I have never seen a 32 mm exhaust valve support 200 hp unless the engine was turbocharged.

FYI: I am running a 1776, with 041 heads 39x35, hemi cut, 40cc chambers, 11-1 comp static, web 163 cam, straight up, 1.25 rockers, Dual Kads, 32 vents,
pwr pully, lightened flywheel, counter balanced crank,
all engine components balanced.....Kennedy stage 1,
Mallory trigger, 34 degrees advance for MSD 6AL,
Merged ceramic S&S 1 1/2" with stinger
Fuel E-90
build about 1.5 years old
Runs Great :D

Fri Mar 30, 2018 9:09 am

jeffinohio wrote: So,good head or bad head for a 1915?Compression,cam,and carb/exhaust recommendations?My wife and I drive this car daily.A couple of 3 or 4 hour trips a summer.73 Standard Bug,stock gearing,slightly taller rear tires.Not looking for a screamer,just a good tourquey motor probably never see 5000rpm.

Depends if you want to buy new heads, or spend a little to improve the 041's.

Ideally for an easy to build great cruiser, I would build this.

69x95, MOFOCO 37x32, or a set of Tim's ported 37x32 heads, a Web 163 cam w/1.3 rockers, .045" deck, 8.8:1, 40IDF's w/30mm vents, light flywheel, CB magnaspark 2 kit, and an 1 1/2" sidewinder header.

Or if you don't want to buy new heads, pull the 041's apart, Unshroud the intakes carefully. Blend the bowls good, have a nice 3 angle valve job done, and run the Web 163 +2deg. advanced.

Brian