other then porting the egr walls behind the throttle body and gasket matching the runners to plenum is there anything else to do to the plenum?

 

Believe it or not, there is quite alot that can be done, including the siamesing of the STOCK runners...only slightly but it can be done. Check it out:

Thread Link

There's a few links in that thread worth checking out.

Also, grinding down the walls just after the Throttle Body opening will increase airflow.

 

grab hold of some slp runners and port the plenum to match and watch the flow begin.

 

See pic.

 

im just gonna save up for an edelbrock runners and base and port the plenum to match the runners but until then i can just grind the egr walls behind the throttle body?

 

what are you guys using to port with, tools wise? i got a carbide bit for my dremel tool and it sucks... its taking absolutely forever. so if yall can point me in the right direction pls do.

btw nice job HD4mula that looks very nice.

 

maroon try dipping the bit in some engine oil or spray some WD-40 around the area your "cutting away" i found that this helps....(if the bit seems dull again or isnt cutting that easily just redip it or respray the area and it should start cutting easily again...

i just did the mod guitarjunki posted a link to tonight... should be on the car tomorrow for testing... except i only did the runners and the plenum not the base.. that i'll save for when the heads come off sometime this winter and the porting begins!!!

 

Sounds awesome, lets hear what you find.

And marooniroc, I used my dremel with a carbide cutter to port a little on my aluminum heads and so far that has been taking out metal fast. So I would think the intake would work just as well. Try the oil method as mentioned, and also, make sure you are using the right cutter for the job, there are a few out there. Also, if it is a cheap cutter, you won't see great results.

 

Thanks but that is not my work. I sent this plenum to be ported to Coervetteplenums.com. Awesome work for the price I think. I would never been able to do such a nice job

But I did my lower Edelbrock porting. I used a grinding kit sold at HarborFreight for $20 (8 tips) and it worked great with my air grinder. I used oil and cut was fast. At the end I used a sanding paper drum to smooth it out. Here is how it looks.

 

just finished up putting the car back together and took it for a quick spin around the block... only got to do 1st and 2nd gear kinda pulls....but the car feels much better in the top end.... before it use to kinda have that brick wall feeling around 4500-4700...and then kinda flat line if you went to 5500...now it pulls pretty easily to 5500 in a linear fashion... instead of hitting a wall then kinda going nowhere till 5500.. instead now its just smoothness.... i didnt take to much out of the runners... maybe half an inch and then i siameesed the plenum... but for the runners i made the divider between them in an airfoil shape.... this should help with airflow going into the runners instead of flat walls....but for the amount of time it took me... and cost (none) it was definetly worth it!

 

Glad to hear you had awesome results. Makes me feel better now with my heads and cam that are going in in a few days. How much time did you spend porting, and what kind of tools did you use?

 

it took me awhile because i wanted to do things right and not cut through in areas... so roughly a couple hours for the runners and about 30 min for the plenum... for the plenum i used the black kinda thick cutoff disks to chope of the center divider then i used some various bits to smooth it out.... for the runners i used this cylinder looking kinda end-mill bit and i shaped the runner divider into an airfoil... this took the longest time because i wanted it to be even and appear to look like it would flow well... then i used some stones to smooth it out....

 

Awesome, good thinking with the plenum center dividers. Were you able to get through the majority of the runner flange without breaking through? Im just curious because like I said, I'll be there in a few days and I'm just getting all ready. Do you have pics of your work?

 

theres plenty of material in the runners if all you want to do is shape them...atleast 3/4" plus... i really wanted to take pictures but unfortunetly i wont be getting my digital camera back till sometime during the week... because i lent it to a certain member of the family and she dropped it.. so its getting fixed... i just used the pics from index but i made my runners look more like an airfoil then the C shape he did... i made everything smooth and flow nicely aswell so there wasnt any sharp edges its all nice and smooth transistions

 

other then matching the plenum to the runners and grinding the walls behind the tb is there anything else you can do to the plenum??

 

Not really. If you DIDNT want to siamese the runners, then there are walls in between each set of holes, kind of like the ones behind the TB that can be ground away.

 

 

Here is a pic of my plenum and the cutting involved with the template that was made.




Here is a shot of the runners opened up a bit.

 

hey man thanks for the tip i tried cutting again and this time used some lubricant and it worked alot alot better. so thanks for the tip guys.