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[Gaz]

Correct me if I'm wrong or this has already been said, but you would want SOME roughness in the intake tract for tumbling, wouldn't you?

[EShepherd]

Correct me if I'm wrong or this has already been said, but you would want SOME roughness in the intake tract for tumbling, wouldn't you?

There's multiple schools of thought on that. Some people leave the floor of the intake ports rough, to get that tumbling effect. I personally smoothed them all out, because I'm doing a tiny bit of re-shaping. I'm attempting to use the Lovell effect to achieve that same tumble, while still getting the velocity increase from having the ports smoothed over. It's really up to the guy who is doing the work. I've seen both ways done, and I've seen both ways achieve significant power gains. To each their own, I suppose.




So here's the progress from last night. Those last 4 exhaust bowls to the far left of the picture (front of the engine) are all that's left to do up top here. I should hopefully be able to get that done today, which will allow me to start on the gasket matching while I wait for my finishing buffs to come in. I still need to order those, if anyone has suggestions. I was leaning towards the Dremel bits that are basically little scotch-bright pads, but I'm not against using cotton and black emery rouge, either. Once both those things are taken care of, it's just the combustion chambers and lapping the valves, then I can start gearing up for reassembly.

Has anyone taken the time to degree their camshafts on a factory rebuild? If so, were they able to be adjusted? Or is it something where I'll HAVE to buy adjustable cam gears?



Edit:
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Just ordered some stuff off of Amazon, and it'll be here tomorrow. I love living in the future . I got a 20 count of 240 grit triangular cartridge rolls, to get into the few tight spots the drums can't reach. I also got a 20 pack of wool/felt buffing wheels, to go with the few that I still have from one off the giant boxes of Dremel bits I picked up at Harbor Freight forever ago. Lastly, I got a 1 pound bar of black emery rouge to use with the buffing bits. All of that, plus the 5000 grit wet/dry sandpaper I got to finish off the combustion chambers...this head is going to sparkle when I'm done. It probably cost me about $100 in consumables to do the whole head, which isn't so bad. It's also cost me about 60 hours of my life so far, and I'm not even close to done yet. That, well that is a little bad lol.

[greywolf27030]

I think cam gears are the only to adjust cam timing.

[EShepherd]

I think cam gears are the only to adjust cam timing.

You mean aftermarket, adjustable gears? After all the work I've put into this head, it almost feels wrong to put it back together with the factory parts. Don't get me wrong, I'm not about to drop $600 on a set of bigger cams. However, I feel like it DOES need something a little special. I can't do bigger valves, because I'm not replacing the seats. I could do nicer retainers and heavier springs, but then I'll need to run a standalone to get the best out of those. I'm thinking I should find some adjustable gears, so that I can really dial in the cam timing. Shouldn't be too expensive, but then again it probably won't give me that extravagant of results. Just a nicer idle and possibly the ability to run a little more timing, so maybe a marginal increase in power throughout the powerband?

I don't know. Any thoughts? I got my tax return, and I want to treat this head with a little something nice. 

[EShepherd]

Well guys, I finished up with that bit! FINALLY! So, here's some pictures. I've gasket matched both the intake and exhaust manifold sides, and then done everything up to the valve seat. All that is left is to get a couple of the small spots the drums couldn't reach in the exhaust ports, and then polish everything up really well. Getting closer and closer every day. The first picture is all the sanding drums and AAA batteries for my headlamp I went through, and that's just from doing the ends towards the valve seats. I had a bigger pile from the manifold ends of the ports, but I threw 'em out before I though about grabbing some pics.

[EShepherd]

So I just finished up the ports. It's really, really hard to show them through a picture. I took a video, I'll try to link to it.

https://youtu.be/mkXGrX4bN7s


Next up is the combustion chambers. They shouldn't take nearly as long as the ports did. I hope...

[greywolf27030]

Not a lot of work, lots of holes....lol  The single cam heads have this weird wall between the valves, I assume to promote swirl. I didn't have a clue what to do with it so I just polished and left it.

[Rocketman]

There's all sorts of upgrades to the cams you can do, but it's all really spendy stuff.

Higher lift is achieved by adjusting the base circle of the cam, IIRC. This lets the HLA's pump up higher I believe. But you'll need to check your valve to valve and valve to piston clearances, I'm not sure if it remains a non-interference motor once you mess with that stuff. There is a limit to how much extra lift you can achieve, and the valves float sooner with higher lift.

There are adjustable cam gears out there.
There are new cams & cam re-grinds available.
There are other OE cams from the B6 with different profiles out there. I briefly played with the N/A auto exhaust cam, the OE XR2 ex cam proved better
There are better springs available
There are solid lifters out there. (bucket over shim type)

All of it is $$$$$$$$$$$$$$$

Dollar for dollar spent, you're better off investing in a better modern turbo and maybe standalone ECU, IMHO
Turbo you can always turn the boost up 

[Aus Capri]

Yea man the pics don't do it justice, in that video you can really see how much effort you have put in! Did you drop the block off at the shop?

[Aus Capri]

Also thanks for your reply on my ecu question, I have only just seen the reply. The microsquirt looks like good value!

[EShepherd]

I never did take it to a shop. The guy I was going to bring it to never called me back, and the last time I had spoken with him he told me it'd take him at least 3 weeks. I decided I'm going to wait for warmer weather, bust out the pressure washer, and try to clean it myself. Hence the port and polish. I've got to kill a few weeks worth of time until winter passes.

If it turns out I still can't get it as clean as I like, I'll revisit the idea.

[EShepherd]

Just a small update. I've been away for a couple days, but managed yesterday to get some work done. I've got 2 of the combustion chambers completed so far. They're coming out very well, in my opinion.

[EShepherd]

Few more pics for you guys. I finished up the combustion chambers. Coming soon - valve lapping (by hand!). Fun, fun.

[greywolf27030]

Man that looks good.

[EShepherd]

Thanks Wolf! I'm so close to putting this back together, I just ordered a valve spring compressor tool. I'm not trying to do the socket & deadblow trick to install the keepers. Never again.