I just got done porting the front of my plenum where the Throttle Body attatches,and since i still have the plenum off,i was wondering if you guys feel it is really worth spending the time to port the inner walls too,like ive seen many people do.I mean i ported the front of the plenum real good,and i took off any extra meet where the runner holes were.But am i gona loose out from feeling a big difference if i dont take out the inner walls near the runner holes?

[This message has been edited by 86TransAmTPI (edited July 12, 2001).]

 

just do it since its already out, and whatever you clear out will help you anyways. it will only take a few moments anyways.

 

The walls are there to add to the length of the runner. Removing them will probably gain you nothing if you're using the individual runners. I did remove them on mine, but I'm using siamesed SLP runners. I have some pics of my porting on my site, if you're interested.

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Bob '89 Ram Air Formula 350
And until that time when death won't wait, let each man rage against his fate. (O'neill)
My car's homepage
Rider's Ride

 

I would recommend doing the runner holes too, When I pulled mine apart my holes were not even round. Get a gasket and grind to that size... It only took me an hour to smooth do all my runner holes on my Phlenum.

AS a side note, When I installed my felpro gaskets I noticed that the gaskets did NOT line up with the holes too well, so I had to grind shape the gaskets as well... Honestly it was more of a hassle to do the gaskets than the Phlenum

John

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87 Formula Yellow/Black
Engine & Transmission
.040 over 5.0 converted to TPI, 9.5:1 Compression, SLP Cam Dur 206/212, Lift 480/487, Cent Line 112, SLP headers, SLP cat-back exhaust, K&N Airfilter, Modified Stock cold air intake, Ported & polished Stock TPI intake, Holley Adjustable Fuel Press regulator, AC Rapidfire Spark Plugs.
Gil Younger (no yo-yo) Shift Kit, Aluminum Driveshaft, 3.73 Posi gear
Suspension & Brakes:
Baer 12" brakes 4 wheels, KYB AGX Adjustable Shocks & struts, Hotchkis strut tower brace, South side machine frame connectors, Custom reinforced control arms and pan hard bar.
Interior:
Custom Leather interior, CUSTOM Yellow Gauge Faces, Kenwood Receiver, Pioneer Speakers, Kicker Substations, Kenwood 10 Disk Changer, Pioneer Amp.

87 Formula TPI (5 Speed) Yellow/Gray STOCK

1967 Buick Riviera 430hp Turns high 14's (Not bad for 4300 lbs)

83 Camaro (Parts)
83 T/A (parts)

http://www.3rdgenformula.com

 

thanks for the input so far guys,anyone else?

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86 Trans Am 305 TPI,Bored 30 over,Blower Cam,Fordged Racing Pistons,High Volume Oil Pump,3" Flowmaster Exhaust,Hypetech Coil,Acell 300+ Race Wires,Bosch Platinum +4 Plugs.Best Et was 12.5 with a Paxton.

 

I just put my plenum back on tonight (10 minutes ago it was running) & have a story to tell about it. I'll post it, but about your question...

My dad did my porting (he owns a roto-zip and some sanding attachments) and ruined all of his bits before completely removing the extra meat inside the throtle body-connecting section of the plenum (the square blocky section of the plenum just as the air enters), but managed to smooth them over (made them hills instead of walls). I said it was fine (I took the plenum off to polish it...well worth it...mirror shine) and finished my polishing. Can I tell a difference in throttle respsonse? OOOOOOHHHHHH YYYYYYEEEEEEAAAAHHHHH!!!!!! My first run out (the car's been out of commission for a week), I switched into second on my auto tranny...and my tires managed to break loose. Incredible! I'll probably never seriously get into drag racing, so it won't hamper me in the long run. If you're serious about competing...take the extra time...It's all up to you and your wallet as to how much time/money you'll spend. Oh yeah, along with an air foil, porting your plenum gives you a somewhat more rich exhaust note. Hope this helps.

Jon

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~3.1EyeCandy~
"The Car that started my craze"

'92 Firebird 3.1 (A car sold)

My new baby: '87 flame red GTA 350 w'auto
Carmine interior with pioneer all around
Hooker Catback, Airfoil, K&N
http://3.1EyeCandy.tripod.com

 

sorry, double post

[This message has been edited by 3.1EyeCandy (edited July 13, 2001).]

 

Thanks a lot for the info Jon,i think ill do a full plenum porting now anyways since i have some free time and it sounds pretty good to me from what i been hearing..I noticed with my cutting bits i bought,i was cutting and in about 10 mins they were filled with metal and not able to cut anymore.But i took a nail and used the tip of it to pry the metal off the bit that collected on it.And to help prevent it from accumulating more on the bit,i had a windex type spray bottle with water in it next to meet.Id soak the bit and the area where i was cutting a real real lot,and the bit barely accumulated metal so i was happy,and i was getting done a lot faster than if i didnt use water when i was doing it.I know that RCR above(whos car is off the hook by the way)was using wd-40 i think when he did his porting.But all i know is if you dont want your bits messed up,its good to lubricate them and keep them cool when you cut.

Ill give everyone a link to see my car pics and the engine compartment as soon as im done throwing it back together.Its looking pretty good so you know,i wanna show it off,lol...But thanks again guys

 

for your cutting bit plugging problem, they do make aluminum cutting bits that have larger serrations in them so they wont do that. I had to buy one when I did my heads, wasnt going to keep wasting time cleaning out the ones designed for iron. It wasnt cheap but worth the 20-30 I payed for it at a local welding shop.

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'87 Monte Carlo SS,with '89 IROC 350,700 trans, blew up 3.73 posi stuck with crappy 2.73's neeed gears! hooker headers, flowmaster 2 1/2" exhaust true dualls, recently installed a set of alum vette heads 58cc, new cam for a paxton, recently installed paxton, OMG need a posi bad. So if anyone knows where a buick GN 8.5" rear is let me know.