01-31-2004, 06:30 PM
For those who have had the intake (s) off their car and actually looked unlike me :)
Was there much a difference between the size of the port in the gasket vs. the actual port size? Did the ports on upper and lower intake match up well or was there a lip? I am looking into the possibilities of port matching the upper and lower if it is worth the time. Thoughts on this?
01-31-2004, 06:54 PM
It's a good idea..... When you start doing all those little thing here and there like porting and polishing it all adds up to make a noticable difference. But one thing to remember that bigger and smoother is not always better. Granted that yes anything bigger than stock is going to be better and I find that a good rule of thumb is to stick right around gasket size. It's not hard at all to port an alluminum intake and heads. I would only port the heads while they are off the car though. Don't wana take any risks of the flakes getting inside the motor. Just be sure the port the lower intake on both ends.
01-31-2004, 07:34 PM
I can't remember for sure, but I think the holes of the metal gasket between the upper and lower IM were a little bigger than the runners' inside cross-section. I think when TC does his stage 2 and 3 IMs he opens the runners up to match the gasket holes. But as TuscaniGTSC2 says, you definitely want to take anything off of the engine to do port-matching or polishing. Take a look at my cardomain page in my sig. I have a page describing how I port-matched my upper IM to my 60-mm BBTB, and then another page when I installed my NGM Stage 3 (with lots of pics of the difference between stock.)
01-31-2004, 11:24 PM
I have experience porting GM small block heads and intakes so experience isn't an issue. I was more curious about how much room there is for improvement where the surfaces meet and from the sounds of it there is plenty. Nothing wild but more of an improvement in the transition from in flow from one plane to another. With the way these engines respond to breathing mods I suspect there should be some improvement. Thanks for the info, saves me the effort of having to tear it apart in the name of research. Now to get all the tools home from the shop :P
02-01-2004, 01:31 AM
The gasket is about 1-2mm on each side bigger then the port itself. I port matched to the Gaskets and IM spacer. There isd some good material to remove. Definately worth it especially if you are going NA. Every little bit helps...
02-07-2004, 08:43 AM
Well I am almost done with the porting job on the intakes. Upper is complete and lower is 1/2 way there. Now that I have seen it in person I can see where there is some room for improvement with some minor porting. The lower intake is the worst by far with it's angled transition where the two intakes meet. The heads seem like the next logical step. Hard to believe this is a performance engine by looking at the stock ports.
02-07-2004, 10:02 AM
Ok, concerning intake porting...
WOW what a difference! I expected gains but daaaaaamn. Well worth the time and effort. Can't wait to see what head porting gets us. Just goes to show how restrictive the induction is on this engine. Responds very well to flow improvements. It is not how much material you remove but where you remove it from.
02-09-2004, 08:43 PM
yup, definately a worth while mod. The transition on the lower where the injector bosses are is pretty rough. Alittle port blending goes a long way..
02-10-2004, 12:46 AM
So I am guessing if I was to do this, I would need to get the TB/IM gasket, the gasket between the upper and lower IM, and the gasket for the the lower IM?
02-11-2004, 06:19 PM
Actually they are all steel gaskets so you may be able to get by without new ones (I did). Having some for back-up though may not be a bad idea. A few tips...
1. After your done be damn sure you have all the debris cleaned out before you reinstall
2. Cover all open ports remaining on the heads or lower intake while you work
3. Take your time and pay attention to detail
4. Pretty does not = power, smoothing it all out isn't the idea here
02-11-2004, 07:08 PM
Are you saying don't bother to smooth it out, or that you will actually lose some of the gains by smoothing it out? Also, what type of bit/attachment is best for porting. I know you can buy special kits and stuff offline, but are they really worth it. I would definitely buy a kit for the heads, but what about just doing the IM/TB