TPI Air Foil and Porting the Plenum
Thread Starter
Supreme Member

Joined: Feb 2000
Posts: 1,170
Likes: 0
From: Seattle, Washington
Car: '87 IROC-Z/'82 RX7
Engine: SBC 355/1.1L Rotary
Transmission: T56/5 Speed
Axle/Gears: 4.33/3.93
TPI Air Foil and Porting the Plenum
'85 Z28 305 TPI
What is an air foil, how hard is it to install,and what exactly does it do?
Porting the plenum: How hard, and what exactly do I drill out?
I'm not extremely familiar with the TPI system, other than seeing it for about a year, and tinkering. I've got a haynes and chilton book....?
What is an air foil, how hard is it to install,and what exactly does it do?
Porting the plenum: How hard, and what exactly do I drill out?
I'm not extremely familiar with the TPI system, other than seeing it for about a year, and tinkering. I've got a haynes and chilton book....?
Member
Joined: Nov 2000
Posts: 343
Likes: 0
From: Snellville, GA USA
Car: 90 Formula
Engine: 350
Transmission: 700R4
An air foil is about 40 dollars out of any performance magazine. It is supposed to create a smoother air flow and it only takes about 5 minutes to install. I would go ahead and pick up a K&N filter too if you don't have one.
Porting the plenum can take up to an hour after you get the plenum off if you do a good job. It is kind of hard to explain, but there is an article in the tech section. Hope this helps.
------------------
1990 Formula 350
*Hooker Headers
*Flowmaster 3" Catback (no cat)
*Accel AFPR
*K&N
*Airfoil
*'99 16x8 Formula Wheels
*Metco Lower Control Arms
Porting the plenum can take up to an hour after you get the plenum off if you do a good job. It is kind of hard to explain, but there is an article in the tech section. Hope this helps.
------------------
1990 Formula 350
*Hooker Headers
*Flowmaster 3" Catback (no cat)
*Accel AFPR
*K&N
*Airfoil
*'99 16x8 Formula Wheels
*Metco Lower Control Arms
SLP sells the airfoil for around $30. Mine was $25. Porting the plenum is fairly easy. You'll need a rotary tool of some sort. Might as well make a homemade adjustable fuel pressure regulator while the plenum is off.
------------------
91 Formula
305 TPI 5speed
1LE/G92/WS6
K&N, SLP airfoil, ported/polished plenum, March pulleys, TB coolant bypass,Crane AFPR(47psi),Crane Gold 1.6rrs,MSD coil,MSD6AL, Holley 9mm wires,Bosch O2sensor, SLP headers & catback,3:73s w/Auburn posi,180* t-stat,JET 195* fan switch, Macewen white face gauges, Autometer gauges, Zoom hi-performance clutch.
Street legal with stock throttle body, runners,intake manifold,cam, and heads.
------------------
91 Formula
305 TPI 5speed
1LE/G92/WS6
K&N, SLP airfoil, ported/polished plenum, March pulleys, TB coolant bypass,Crane AFPR(47psi),Crane Gold 1.6rrs,MSD coil,MSD6AL, Holley 9mm wires,Bosch O2sensor, SLP headers & catback,3:73s w/Auburn posi,180* t-stat,JET 195* fan switch, Macewen white face gauges, Autometer gauges, Zoom hi-performance clutch.
Street legal with stock throttle body, runners,intake manifold,cam, and heads.
Thread Starter
Supreme Member

Joined: Feb 2000
Posts: 1,170
Likes: 0
From: Seattle, Washington
Car: '87 IROC-Z/'82 RX7
Engine: SBC 355/1.1L Rotary
Transmission: T56/5 Speed
Axle/Gears: 4.33/3.93
How do I make a homemade fuel pressure regulator? What's it's purpose. I don't know what kind of pressure I need. Is it like... I want to go fast, I give it more pressure, or what? Why would I want it adjustable? Thanks
Forget the airfoil, it's a waist of $$, neveer felt of did any diff on my car, if you are going to do mods, then do mods, don't play around....porting your plenum will give you a good improvement that you can feal, K&N's are good for the fact that you can clean them and never buy filters again. Save the 40$ from the airfoil and get some good set of wires or some gauges or best, buy a fuel regulator so you can "tune" you car a little bit better.
My .02$ rock on!
My .02$ rock on!
http://members.aol.com/mmmm999/3rd-degree/tips/tips.htm
search and bookmark this site , it will help you out in your questions.
plus look on ebay for a cheap airfoil.
search and bookmark this site , it will help you out in your questions.
plus look on ebay for a cheap airfoil.
Senior Member

Joined: Jul 1999
Posts: 900
Likes: 1
From: Haslett, MI
Car: 1984 Trans Am WS6
Engine: Minirammed 385, 396 RWHP
Transmission: T56
Axle/Gears: 3.73 Moser 12-bolt
How do you port a plenum in one hour and still do a good job?
My best time so far is just under two hours. That's with a 25,000 RPM Ingersoll Rand Cyclone pneumatic die grinder, three long-shank aluminum carbide cutters, one short-shank aluminum carbide cutter, and various coarse and medium grit sandpaper rolls.
I've done about half a dozen plenums to date.
------------------
Daniel Burk
http://www.isthq.com/~dan/fcar.html
'84 Trans Am WS6/L69
KB SFC, Moser axles, Torsen Diff. PST suspension, Braided stainless brake lines, Koni struts, 11-inch rear disks,Spohn Adj. torque arm,
Ported 305 heads w/1.94"intake valves, Comp Cams XE262H, Griffen alum. radiator,
Turbine Technologies 2500 stall converter, underdrive pulleys, Crane Hi-6 & more.
1.05g skidpad verified.
New best E/T! 14.039 at 100.82 MPH in 41 degree air at Stanton, Michigan.
My best time so far is just under two hours. That's with a 25,000 RPM Ingersoll Rand Cyclone pneumatic die grinder, three long-shank aluminum carbide cutters, one short-shank aluminum carbide cutter, and various coarse and medium grit sandpaper rolls.
I've done about half a dozen plenums to date.
------------------
Daniel Burk
http://www.isthq.com/~dan/fcar.html
'84 Trans Am WS6/L69
KB SFC, Moser axles, Torsen Diff. PST suspension, Braided stainless brake lines, Koni struts, 11-inch rear disks,Spohn Adj. torque arm,
Ported 305 heads w/1.94"intake valves, Comp Cams XE262H, Griffen alum. radiator,
Turbine Technologies 2500 stall converter, underdrive pulleys, Crane Hi-6 & more.
1.05g skidpad verified.
New best E/T! 14.039 at 100.82 MPH in 41 degree air at Stanton, Michigan.
Trending Topics
I ported my plenum in about an hour too. I used about the same tools you did (maybe less) and did a pretty good job I thought. It took a lot longer to take the plenum off and put it back on, but I think I would pass out after 2 hours of just grinding and sanding. I don't think he was trying to give an exact time period anyways. Maybe I didn't do as good of a job as I thought?
Joel
------------------
1989 G92 TPI Formula
Random Technology Exhaust
Accel AFPR
Air Foil
K&N
MSD Ignition
3.73's (I think)
White Face Guages
Pro 5.0 Shifter
Joel
------------------
1989 G92 TPI Formula
Random Technology Exhaust
Accel AFPR
Air Foil
K&N
MSD Ignition
3.73's (I think)
White Face Guages
Pro 5.0 Shifter
Originally posted by mirage2991:
Forget the airfoil, it's a waist of $$, neveer felt of did any diff on my car, if you are going to do mods, then do mods, don't play around....
My .02$ rock on!
Forget the airfoil, it's a waist of $$, neveer felt of did any diff on my car, if you are going to do mods, then do mods, don't play around....
My .02$ rock on!
All mods don't have to be big ones. Do a combination of little ones . Plugs alone won't do much. But maybe plugs with low resistance wires and an MSD coil will...
Airfoil increases airflow very slightly. Dyno rwhp varies from 1 to 7
------------------
91 Formula
305 TPI 5speed
1LE/G92/WS6
K&N, SLP airfoil, ported/polished plenum, March pulleys, TB coolant bypass,Crane AFPR(47psi),Crane Gold 1.6rrs,MSD coil,MSD6AL, Holley 9mm wires,Bosch O2sensor, SLP headers & catback,3:73s w/Auburn posi,160* t-stat,JET 195* fan switch, Macewen white face gauges, Autometer gauges, Zoom hi-performance clutch.
Street legal with stock throttle body, runners,intake manifold,cam, and heads.
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