Would removing just the EGR bump in the exhaust port be a worth while job??
What other easy porting could be done yourself??
I'de like to get Thumper heads, but can't you get some stock E7's from the junk yeard for cheap??
E7's can be had very cheap, if not for free. Just look/ask around for someone in your area.
Only removing the smog bump will not doo much if anything, while you in there hog out the exhust ports where the most restriction is. the intake side it pretty much ok, and there is not much room for porting there.
Actually, I've heard some good results of just the EGR bumps being ground down. I thought about porting my heads myself. Porting to the level Thumper does takes alot of time, and there is more to porting than just making the holes bigger with a die grinder of dremel. When you count the valve job and his skill, the thumper heads are a better way to go. The spring upgrade is also a good deal. You could go in and just use common sense to where the restrictions are but if you dig too deep you'll open a water jacket and the head is pretty much done.
I rebuilt and ported my E7s way back. after the many hours and $550 of machine work and hardware, it's not worth doing it yourself. Bare in mind max you'll get out of them if you're luckey, is around 200 cfm. That's not a good bang for the buck if you ask me. TF gets 251 cfm for around $1000. If you're dead set on E7s, go with Thumpers heads. You'll feel a difference.
i have also read that just the EGR bump won't do a whole lot. The exhaust ports in E7's are pathetic - they only flow about 120 cfm. In order to increase that number, you'll need to open up the exhaust port to a larger size. If you have a set of headers, you can make a template out of paper that matches the size, shape, and location of the port. Then, scribe on the head, and go to town. Most shorty type headers won't have an opening that's big enough to get you into trouble (i.e. grind into water passage). You'll neveer get there if you use a dremel, and the air die grinders will have your compressor runnign full time. The only way to do it is to buy an electric die grinder (they run from about 100 to 250), and some good carbide bits (about $60 for a set). It may not be the best bang for the buck considering that you'll probably need to buy the tools, and then you'll still spend a few hundred getting the heads rebuilt but its still cheaper than new heads, and its something that you can say you did yourself. If your running a stock intake, no need to mess w/ the intake side of the heads - it already flows as well as the intake.