Need Help With Magnum TPI Project Car--Induction Solution Needed

If you're following the GMHTP Third-Gen Formula project car (Magnum TPI), you know we need help getting air into the motor. We take the induction off on the dyno and run an open throttle body and get 30 more horsepower at the rear wheels. When we put the stock induction back on, it goes away.

I have considered many options including: a functional ram-air hood (it ruins the lines of the car in my opinion), an SLP Third-Gen Firehawk dual snorkel set-up (battery needs to be relocated and there's probably not enought room with the big radiator and SuperRam intake), and custom ductwork squeezed between the engine and radiator on the passenger side (same path as stock, only larger). The last one I'm not too fond of because of all the bends and tight clearance between the radiator and throttle body--we'd probably give up some power on that one.

The car has been converted to speed density via a Gen 7 DFI so a MAF is not needed.

I was looking at an IROC/Z28 dual snorkel inlet but I don't know if it will clear the hood and latch mechanism. (The front bulkhead in front of the radiator would have to be cut for the filters, no big deal).

Another solution I'm looking at is leaning the radiator back with a custom radiator support and using a C4 or C5 intake over the front of the radiator and under the front bulkhead. The straight shot of air would be the least restrictive (IROC or Corvette solution) so that's what I'm leaning towards.

Has anybody worked through a similar solution that can give me some advice and possibly some pics? (If we go with your solution, we will give you credit in the magazine with a photo of your airway solution from your car.)

I too am facing a similar dilema. I have a Mini Ram intake on my car, a big Be Cool Radiator with their dual fans, and a 92' serpintine drive. I bought a Flowmaster 3.5" universal exhaust kit in hopes of building some sort of air intake. It's going to be hell trying to get it to make that sharp turn out of the TB and towards the drivers side of the car. I have the stock TPI air cleaner plastic "Y" piece and a 90'-92' SD car bellow to go from the TB to the air box. I am hoping to dyno it with both and see what happens.

Someone I know with an LT1 intake on his car just swapped in a big Griffin radiator and is having similar issues. He had previously built something similar to the SLP dual inlet unit - but, it no longer works. Be sure to keep us all updated on this matter.

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1986 IROC-Z, 8pt. cage, 383, Mini Ram, DFI, Art Carr 700R4, 12 bolt.....

[This message has been edited by 86 IROC (edited August 18, 2002).]

I remember reading about yout air induction problems. I have really been looking into this issue. I just can't see how enough air could flow through the factory "Y" shaped air cleaner assumbly. I know a stock motor will not max out the MAF but put huge heads on it and a mean cam and then you start getting restricted by the "Y". I have seen a few people on thirdgen.org custom fabing CAI's. They had 90* bends in them but us MAF guys have limited space to deal with. Best bet would probably be to tip the radiator back and try and run ducting over the top and down through right behind the fog light locations. It would serve as a Ram-Air setup also at higher speeds.

I know this isn't much help, I'm just kind of thinking out loud. I also want to tackle this. Anyone have and other suggestions?

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-Brad C?
355ci '89 Iroc-Z Red, T-tops, power everything, A4,New 10 bolt w/ 3.73's
Trans-Go shift kit Corvette Servo,Accel 8.8mm wires,Flowmaster 80 series ,K&N's, !MAF Screens, Hollowed out airboxes,homemade Subframes. Kieth Black pistons 10.3:1, Comp Cams 270H (.495/.502 218*/224* 110*LSA) & valve springs, SLP 1 3/4" headers, TCI 2400 stall, Dual Roller timing chain, 2 3/4" I-pipe.
Full street trim best run:14.799/mph:93/60': 2.02 (last year) New Times to come.
New times: 13.732 @ 99.30 on a 1.878 60'
Pics of the Iroc (http://y42.photos.yahoo.com/bc/diablo_49418/lst?.dir=/Diablo%27s+photo+album&.src=ph&.order=&.view=t
)

Try a 4th gen CAI kit. Try to swap one from the Firechicken into the bird just for a test fit. If that doesn't work, try to take a 4th gen 1LE intake elbow and fab something up to that...That should take care of your sharp curve and fabbing the rest would be easy. I've seen several people here locally with LT1 swap use 4th gen CAI's in their thirdgens without problems. (Although the LT1 does sit a little low in a thirdgen engine bay).

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1987 Flame Metallic Red IROC-Z Camaro. LT1 motor installed. http://home.attbi.com/~markolc

Did you ask this on ThirdGen.Org's Tech Board and TPI Board??

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Camaro/Chevrolet crazy F-Body lunatic. :)

I have a single slp intake on mine. It is all oem quality stuff. I put a 3'' pipe were the maf sensor was since i changed over to sd. They sell a sd ver is this one though.

http://bitchincamaro.no-ip.com/tpi.html

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http://bitchincamaro.no-ip.com (http://bitchincamaro.no-ip.com) 91 RS Camaro 5-speed black w/t-tops 305 TPI
MODS: SLP cold air intake w/K&N, air foil,Accel 19 LB injectors, March aluminum under drive pullies, Alburn pro posi, Aluminum drive shaft, Random Technology 3'' cat-back, 8.5mm MSD wires, 160 thermo, jet fan swich, Custom chip with 91 vette computer, SSBC slotted rotors, optima battery in the rear, BMR adjustable lower control arms and panhard rod, Kenny Brown strut tower brace, TB bypass, no egr, no air

Just an idea and maybe you already tried it, but what about just slapping a filter on the throttle body? I know you would just get warm engine air but it would still cut down on the sucking through a staw effect.

BTW you mag rocks, been a subscriber for 2 years!!

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2001 Formula M6,
slp lid, !cags, FTRA, hurst/lou's, Borla cat back, DMS STB, LCA, LCA Brackets, PHR, SFC, and lowering springs

88 GTA (current project) completion date 1 July 03

2002 Gran Prix GT

Is there anybody out there who has actually done any of this? If you know them, see if you can have them post some jpegs.

On to something else. Three inches is too small (you can ask my wife!). I'll need the equivalent cross-section of a four-inch pipe.

I did post this on Thirdge.org. No responses yet.

I got an 8" piece your wife can try. http://web.camaross.com/bb/biggrin.gif haha jk Johnny!

ANYWAYS...a 4" duct will have to be custom made out of either PCV or metal tubing. Maybe PCV can be softened with hat and then bent to whatever specs you need? And or take it to a metalfab shop and have them make something nice. I'd route it to the passenger side fender like a lot of stock applications do. Goodluck

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Denny Villemure
1989 Camaro IROC-Z Convertible, 305 TPI, 2.73 Gear, Flowmaster 2 chamber. 15.60 on motor, 14.20 on a 75 shot from NX. Woo hoo!
www.denny.cz28.com (http://www.denny.cz28.com)

I'm curious as to how restrictive that factory "Y" shaped platic air box really is. I did some digging through old magazines and found a car built by another magazine. It ran a 420 ci SBC with a SR. It used the factory box and bellows. It ran in the 10's on the muscle of the motor. It also had a 3" SLP cat back 2OL system. I couldn't find any real comprehensive dyno tests on it though. In one issue they did a T-5 to a Tremec TKO swap.

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1986 IROC-Z, 8pt. cage, 383, Mini Ram, DFI, Art Carr 700R4, 12 bolt.....

I would have a custom 4" mandrel bent pipe with a K&N cone on the end under the facia of the car. If you want an example email KandiedZ and he will show you his custom setup. It flows better than anything aftermarket out there.

The builder of the system is Performance Fabrication & Engineering 586-949-3400
It can also be coated or polished.



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Mike L.

1987 IROC Z 5.7 TPI A4 3.27 Borg-Warner four wheel disc
Mods: 2300-2500 Stall Converter, Shift Kit(GM parts), TPI Specialties Stage 3 PROM, Modified airbox w/ K&N's, Relocated MAT sensor, Gutted MAF, 160* thermostat, MSD 6A, Accel 8mm Wires, bypassed TB coolant, 3" Flowmaster 3 chamber single outlet, custom adjustable cutout, 3" MAC mandrel intermediate, airfoil, ported plenum. !smog, Crane AFPR, Accel rail mounted FP gauge, Harlan shiftlite, 24lb. injectors, Hedman headers, a few others I forgot...??? FINALLY GOT PAINT!!

Check out my IROC webpage! (http://iroc5.7tpi.home.att.net/wsb/html/view.cgi-home.html-.html)

You can look at pic in my sig link to see my crappy ace hardware induction system.

You can also order the vortech supercharger inlet elbow from summit, but the vortech elbow is 3 1/2 inches, not 4.



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89 Trans Am GTA (http://www.thirdgen.org/rides/index.tgo?action=view&rideid=6342)
99 Kawazaki ZX9R
93 Ford Tempo

Johnny- No direct hands-on expereince on this subject, so you can take the rest with a grain of salt. My brother is in a similar situation (409 small block with miniram in 87 GTA). There's no easy buy-and-bolt-on solution to this or I would have found it by now, trust me.

Here's one of several things we're considering, however. 4th gen style ram-air hood but built for a 3rd gen. Don't barf. Hear me out. I think mixing generations looks like crap in general, too. But this one even passes my conservative tastes with flying colors. I'll see if I can remember the company and post again soon. I've seen a few IN PERSON and they look as good or better live as they do in pictures.

Custom air box to make it work? You bet.

Pain in the a$$? You bet. If you want bolt-on everything buy a Civic.

Would it be the simpest path? Probably.

Let me throw out a few other ideas I've had about this, not that I'm in a position to built any of them currently, without help from friends who are body-shop gurus:

1. Get the air from around the sides of the radiator. A la SLP dial-snorkel. Been there, wrecked that.

2. Get if from on top of the radiator. You can't do it like an IROC since the hood is so much lower and the intake plumbing would interfere with the upper radiator support. You know that and consider leaning the rad back further. OK, fair enough, but you think cooling will suffer? You'll have to lean it quite a bit to get any maninigful clearance, or drop the lower support, putting it dangerously close to speed-bump level. AND you're close to maxing out a stock-area radiator with the heavy-breather big cube small block almost certainly. I think you might regret this one, long term. This is also not something your average reader would consider unless the custom rad support could be bought readily for themselves (IMHO).

3. Go UNDER the radiator. Dirt cheap, kinda convoluted intake path, where do you put the air cleaner(s), not much clearance anywhere under the rad for speed bumps, you'll pick up TONS of dirt and filth while street driving etc. Yuck.

4. Forget about the radiator. Remember Cowl induction??? Yeah, it looks FANTASTIC on a 3rd gen. Kinda retro, but kinda a look all to itself, too. Befinitely bada$$ Cowl induction hoods can be had for nexta nothin. Box it in underneath, make a place to mount a rectangular-style flat filter, a single 180* bend to get it into the forward-facing throttle body and you're there. Also, no limitation on breathing area- that big rectangular space has TONS of room to flow.

Love the mag. I know this is only some ideas but I hope it was worth the read just the same.

I see where my idea about the 4th gen CAI might not work great for you because you need to relocate the battery (which I know you may not want to do, but it could make a very good step by step article in the future in addition to adding a battery disconnect switch, hint, hint http://web.camaross.com/bb/wink.gif) But looking at the picture of your Formy in the latest Mag (the one where it's at the Second Street Speed dyno) I see you leave the MAF in the place of the ductwork. Why not remove the MAF from the ductwork and dyno the motor with just the Elbow on, and see if that's your restriction. If that's not the restriction you should be able to use the factory ductwork (minus the MAF) and just fab a cone filter to the end for a nice low-buck do it yourself mod (or gut the stock box).

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1987 Flame Metallic Red IROC-Z Camaro. LT1 motor installed. http://home.attbi.com/~markolc

Yep. Been there, looked at all that.

Nobody here actually find a solution to this in a heavy-breathing third-gen Firebird?

There's absolutely no way I've got the fastest TPI 'Bird on this forum...

Hey, they've got .jpegs for you on Thirdgen.org under your post.

I had to fab some stuff with the LT1 swap too. Difference is I was able to make use of a TPI airbox while you've got that metal plate up front on the Formy.

Dude, get your hands dirty. Cut a hole in the passenger side panel. Not sure what sits there in the Formy. But in my Camaro that's where the battery sits.

Cut a hole, put a sheetmetal aribox underneath there, pop a K&N conical or whatever you prefer filter down there and then get some aluminum tubing made. Only hard part will be getting the adapter to the TB to bend right and down correctly. But that's really not a big deal. Then run a straight pipe over and cut it to accomodate the MAF.

Honestly, that is a REALLY simple job and it'll do a great job. And if you get the tubing polished it will look killer, too!

Design to install should take half a day on a weekend. Get it set up and working, then polish it.

I don't see the problem here. Just get it done and drive the car. I want to see sub-13s this time! That thing should DECIMATE my C5. Thanks for the responses to my e-mails about my problems with that car, btw. http://web.camaross.com/bb/wink.gif

Good luck with the 'bird!

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'91 RS Camaro - red/black, '95 LT1-based 355 w/ the infamous red intake

'00 C5 Coupe - black/black coupe, 6-spd, factory polished rims.

Chewbacca is NOT dead!

bs.cz28.com
350.streetracing.org/lt1d.html

Johnny,
Go to 3rd gen under the power adder board and look under my post "10.36@130 with a 150 shot". It has some pics of my CAI and a little info on it.Maybe some food for thought for Magnum.
Glen

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91 Z28 406
11.34 118 N/A
10.36 130 N2O

Johnny, here's your solution. Who's looking out for you?

I was just over at pcmforless.com and caught this link........

http://www.azsupersport.com/raiss.htm

They do Impy SS work, but I'll bet they'd be willing to hook you up for a mention in the rag. Of course, the pictures they have on the site amount to much the same thing as I was describing but on the nose instead of through the battery box (or whatever sits on top of it in the Formy). So they should definitely be able to handle it. Or even in your back yard. You don't think Cartek could do the job?

Anyway - tryin' to help. We need more fast 3rd gens on the streets prowling. http://web.camaross.com/bb/wink.gif

Keep us posted.



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'91 RS Camaro - red/black, '95 LT1-based 355 w/ the infamous red intake

'00 C5 Coupe - black/black coupe, 6-spd, factory polished rims.

Chewbacca is NOT dead!

bs.cz28.com
350.streetracing.org/lt1d.html

I would really try to pursue the idea of tilting the radiator back . You know enuff bout fabbing so I think these pics will get ya thinking http://web.camaross.com/bb/smile.gif You would need a lower LS1 air box for the mount and a LS1 filter and lid , then its time to get creative http://web.camaross.com/bb/biggrin.gif

http://web.camaross.com/bb/Forum1/HTML/109486.html

http://www.madmanandcoracing.com/redcam.html


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Derek 95 Trans Am convertible (http://community.webshots.com/photo/31486877/32064124QctapZSbfS)
K&N fipk , CSI h20 pump , hooker lt's , mufflex 4" , LT1edit , ET streets , 373's , !A/C , !smog
Best Et 12.771@106.89
Best 60ft. 1.820
MTI/GTP stage 3 LT4 heads , cc306 , hyra-rev , 1.6's , r lifters , full manual 700r4 , ST3500 verter , roll bar and more all in the garage waiting for install .
92 Z28 (http://community.webshots.com/album/39961799GTBlwY) - 5.7/G92 , stock daily driver

Hmmm, or you can always go back to the factory radiator. It will keep the engine cool. I'm running a 450hp naturally aspirated 355 on a stock radiator from my RS which had an L03 305 TBI that made 170hp. Car stays at 180-190 ALL day, even after getting on the highway and running at 2700 rpm for an hour.

And that was with the factory water pump and 160 T-stat.

Would be nice to see something laid out in the rag about true DIY stuff. The Thunderchicken 4th gen project and this Magnum one with the Formy have both gone WAY beyond a simple bolt-on or build-up route that most readers can do and its all been done by shops.

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'91 RS Camaro - red/black, NA 450hp LT1 355. Set to run 12psi+

'00 C5 Coupe - black/black coupe, my beautiful lawn ornament.

Chewbacca is NOT dead!

bs.cz28.com
350.streetracing.org/lt1d.html

The Impala stuff IMO has got to be the best design,wish they would`ve showed the car with the hood down so we could see what it looks like.I agree with your styling concerns.
FWIW,I only gained a few hundredths switching from the OEM setup to 4" pipe either on or off the juice.(406 :confused http://web.camaross.com/bb/smile.gifI realize it depends on the engine pulling thru it,but is there a way to literaly flow these different designs to see just how much cfm they can move?I used the SLP ram air that came with the package back in the day and the car went slower,so now it`s sitting in my garage.The plastic duct is just as small as the TB side of the Iroc piece.

Try all of them on the car and report your findings!! http://web.camaross.com/bb/biggrin.gif http://web.camaross.com/bb/biggrin.gif

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91 Z28 406
11.34 118 N/A
10.36 130 N2O

Heres the 4" piece you need and its for sale.

http://www.thirdgen.org/techbb2/showthread.php?s=5a089016dbbe39a9acb0f09895486e9f&threadid=123076

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Mike L.

1987 IROC Z 5.7 TPI A4 3.27 Borg-Warner four wheel disc
Mods: 2300-2500 Stall Converter, Shift Kit(GM parts), TPI Specialties Stage 3 PROM, Modified airbox w/ K&N's, Relocated MAT sensor, Gutted MAF, 160* thermostat, MSD 6A, Accel 8mm Wires, bypassed TB coolant, 3" Flowmaster 3 chamber single outlet, custom adjustable cutout, 3" MAC mandrel intermediate, airfoil, ported plenum. !smog, Crane AFPR, Accel rail mounted FP gauge, Harlan shiftlite, 24lb. injectors, Hedman headers, a few others I forgot...??? FINALLY GOT PAINT!!

Check out my IROC webpage! (http://iroc5.7tpi.home.att.net/wsb/html/view.cgi-home.html-.html)