Porting exhaust manifold

[spoon32]

Tim_K,
What bit did you use with the dremel?

i used a **** router bit to really get at the iron . man.. my grinding stones didnt do a THING. and i smoked a 20$ carbide bit for a luminum on the dang thing.. that cast iron is some NASTY hard stuff...

anyone that has spent a couple of hours on a exhuast manifold to look down and not notice much of a difference will agree here..
it takes alot of time to get into the iron..

BTW a nice Campbell and hussfeild compressor and a die grinder worked great...
my dremel thought i was nuts trying to do that and would bog down with the slightless effort..

[guyd_15]

I got a professional Dremel from Grainger. It cost about $250. It makes cast iron fairly easy and outlasted my pneumatic die grinder.
Guy

[86Shelby]

Getting the first cut into the iron can be tough, but I had no problems with any of the manifolds I have done. Die grinder and a bad to the bone carbide bit from my Snap-On guy. Didn't damage the bit at all after 3 manifolds. I first tried my dremel and it was a waste of time. Spent 4 hours with the dremel to get 1/2 done on the first manifold, spent 1 hour with the air grinder and was totally done with a second manifold.

[Tim_K]

For cast iron, I use carbide cutters with very fine teeth. I have ball shaped cutters, some with straight sides and a rounded tip, and one that is kind of teardrop shaped but on both sides. Looks like an oval more or less.

They each have their uses for certain parts of the ports.

My first porting job was on a /6 head with nothing other than a single 1/8" shank cutter and rounded tip. The CUTTING section was also 1/8" diameter! Needless to say, it took a LONG time! But the /6 picked up 15 HP when I was done with no other changes.

For aluminum, I have one carbide cutter that is large (1/4" diameter) at the base, and has a rounded taper to the tip. It is very coarse, with only 6 teeth. It makes the aluminum chips fly! While cutting aluminum, I stop about every minute or 2 and clean out the pieces from the teeth and dip the cutter in ATF, which helps a lot.

DO NOT use fine tooth carbide cutters on aluminum! They will clog up in about 10 seconds and then it's ruined unless you want to spend a 1/2 hour digging the aluminum out of it.

The last time I ported an iron head, I borrowed someone's 1/4" air grinder and a box of larger size carbide cutters. That thing carved the iron out pretty quickly! A huge time saver. But nothing can beat a Dremel for the final finishing and shaping.

What are the options for electric grinders other then the dremels. I have a dremel and I agree it's for hobby use only. It gets **** hot. I have a pneumatic die grinder but I don't think my compressor can keep up with continous use. I have another tool which I'm not sure will work for this, which is a dewalt 5amp cut-out tool. It's 30k rpm and 1/8 or 1/4 collet.

[The S is Silent]

I have been using a dremel to port my exhaust manifold...basically just opening up the ports and smoothing stuff out...it does go slow, but I don't have an air grinder.

I have been using the tungsten carbide bits. Numbers 9901 and there are a couple others...all start with 99??. You get the point.

It took me about 2 hours to do the 4 exhaust ports...not done yet. If you are going to do it...get earplugs! It is loud!!

[spoon32]

Thanks. That was the info. i wanted all along.

[The S is Silent]

No problem...let us know how it goes.

[BadFastGTC]

Quote:

Originally posted by dragonwagon What are the options for electric grinders other then the dremels. I have a dremel and I agree it's for hobby use only.

This is the tool I use to do port work. The 11.5Amp rating and 14,500RPM makes it a great workhorse. I use it to do all the rough work and finish detail with a wide selection of carbides.

[GovtContact]

Quote:

I've ported several /6 iron cylinder heads and one set of V-8 Mopar iron heads with my Dremel. And one 2.2 aluminum head. Same Dremel, same flex shaft and cable.

Flex Shaft That is the trick...a Dremel alone will soon go into the spare parts drawer.

[GovtContact]

Quote:

Originally posted by dragonwagon What are the options for electric grinders other then the dremels. I have a dremel and I agree it's for hobby use only. It gets **** hot. I have a pneumatic die grinder but I don't think my compressor can keep up with continous use. I have another tool which I'm not sure will work for this, which is a dewalt 5amp cut-out tool. It's 30k rpm and 1/8 or 1/4 collet.

This is what I have/use: Great Toy

[spoon32]

Nice. If i would have seen that before i may have gotten that instead. Doesn't have the rpms a dremel has but it sure has alot more power( 1.15 amps vs. 4.5amps)

[crazymadbastard]

Quote:

Originally posted by BadFastGTC This is the tool I use to do port work. The 11.5Amp rating and 14,500RPM makes it a great workhorse. I use it to do all the rough work and finish detail with a wide selection of carbides.

Man that is a manly tool!

I did my head with sand paper rolls and they do clog up. I used wd-40 and it took the aluminum clogs right out. For the cast manifold I got a nice 90,000 rpm industrial air grinder with a carbide bit- I am sure it will cut it, the stones I got seem to be useless agains cast Iron.

I will post the pics of my tool later.

screw the grinders.. ive seen tons of them. lets see the bots you guys are using to get through this cast iron!!