One of my projects I'm planning this winter is to create a cold air intake for my 4.9. My only issue is I have the Allante intake which has an oval throttle body. I need to know what others have done to adapt some 3" intake tube to the Allante (or SBC) oval throttle body? I want to end up with my air filter down near the factory intake vent. Here's a picture of my current setup I want to replace:

Any suggestions and ideas would be greatly appreciated!

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88 Coupe: Modded 4.9L V8 5 speed
86 GT: Stock 4 speed
86 SE: 3.4 DOHC 4 speed
http://www.geocities.com/fast88fiero

Measure the area of the throttle body, let's say it is 3", then take a mandrel bent piece of 3" pipe, put it in a vie and clamp it down until it roughly matches the throttle body. Then take a 3" coupler and couple them. Pretty simple, but you will need to weld the pipe at its joints to get it down in the fender.

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"all pushrod motor are better than the dohc because it has less rotational mass"
-rick17, MyMonte member, owner of a 3100 Monte Carlo LS

I would check out what is used on the LT1/LS1 series of motors as they also have an oval throttle body. Maybe something for those can be made to work. Also don't forget about the Mustang and other cars that may have an oval throttle body.

Tim

The LT1 throttle body may be a bit too big, and the LS1 throttle bodies aren't oval, they are circular.

It isn't that hard to just get the area of that ellipse (I forget the formula off hand), then find out what radius curcle will need to be to have the same area, then get a mandrel bent piece on eBay and put it in a vice. It is simple, easy, and would look great!

Question for you. When you went to the Allente intake, did you use the stock Allente TB and if so, were any other mods needed to do it other than the manifold?

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quote Originally posted by paulcal: Question for you. When you went to the Allente intake, did you use the stock Allente TB and if so, were any other mods needed to do it other than the manifold?

I did use the Allante TB. You have to lengthen the wires for the TP and intake temp sensors. Other than that everything is a direct bolt on.

quote Originally posted by FieroMaster88: I did use the Allante TB. You have to lengthen the wires for the TP and intake temp sensors. Other than that everything is a direct bolt on.

I had a question regarding this as well. Were you able to retain the ecu that were using with the old intake or did you have to switch to the Allante intake. I am guessing you were able to retain the previous ecu if all you had to do was lengthen a few wires.

quote Originally posted by STRATOHACKER: I had a question regarding this as well. Were you able to retain the ecu that were using with the old intake or did you have to switch to the Allante intake. I am guessing you were able to retain the previous ecu if all you had to do was lengthen a few wires.

I am still useing the ecu from the 4.9. There were no modifications needed for the intake, just some lenghened wires.

The way I did my Allante Intake to make it a cold air system was to us the V6 system and modify it. I removed the neck that the rubber intake hose hooked to and welded a piece of 3" tubing to it I got a mandrel bent 3" tube and cut it to fit to the inlet side of the filter box tis piece sticks out into the area in the wheel well were the old water seperator was. I removed the seperator as I had installed side scoops on my 88. I used a air intake hose from a Chevy S10 and fiber glassed it to my driver side scoop. The hose hooks right on to the 3" pipe from the air box. I had the pieces all powder coated red and run a K&N filter in the box.

Buy the way I run my oil cooler in the other scoop. So both are functional

Joe Sokol

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85 SE 2.8 - beater coupe-
86 SE 3.4 -in progress 3800 II SC -
88 Formula GT 4.9 5 speed beast
Enough parts outside for another one
-And a 3.4 push rod for sale in the mall Go and look-

quote Originally posted by Fieroking: Tried to get a better picture of my setup that is bigger. Hope this one is better. Joe Sokol

Looks good! Thanks!

Has anyone dyno'ed a stock 4.9 with an Allante intake? I'd be interested to see how much it helps. Sure does look good, though.

Hey now Fieromaster, you can't have that 4.9 looking better than your DOHC car all the time! Give the other one some lovin'!

TPI, LT1 had oval throttle bodies. All the sensors shooulllddd be compatible if the 4.9 sensors are like the ones on the 3.4 and whatnot.

quote

That box on the right side of the intake plenum... is that a MAP sensor cover?! That looks trick!

[This message has been edited by Steven Snyder (edited 01-02-2006).]

quote Originally posted by Steven Snyder:TPI, LT1, LS1 had oval throttle bodies.

All of the LSX series had round throttle bodies, measuring 4" OD, and they are all pretty much the same except for teh actuation device and the size. LS1 75mm cable draw throttle body on my old 3.4:

[This message has been edited by AaronZ34 (edited 01-02-2006).]

quote Originally posted by AaronZ34: As I said before, none of the LSX series small blocks have/had oval throttle bodies, they ALL have round ones, including the LS1 75mm unit whether it be cable or not.

What? I never said anything about that!

Thanks for keeping me in line.

F BODY
85 to 92 TPI ovel
93 to 97 LT1/LT4 ovel
98 to -- LS1 ovel
also the s-15 typhoon and syclone used Ovel

I'm with aaron on making an adaptor however fieroking's set up using the factory rubber adaptor should work almost as good. If you want an adaptor that doesn't have that little bend in it get one from an 85 to 92 TPI camero, or for a 90* version get one from an 85 to 92 TPI firebird. You can get them from year one for around 20 bucks, they also offer a few diffrent high flow versions last time I checked.

quote Originally posted by markviiisvt4: 98 to -- LS1 ovel

ALL LS1's had circular throttle bodies, not oval, and they are the same as the LS2, LS6, LS7, etc except in plate size and actuation device. But they are all round. A 1998 LS1 75mm cable draw on my 3.4, again...I'm not trying to be an assm just trying to clear up misinformation.

quote Originally posted by Formula88: Has anyone dyno'ed a stock 4.9 with an Allante intake? I'd be interested to see how much it helps. Sure does look good, though.

I have this planned for spring. baseline (alomost stock Rockcrawl chip) then add the intake and take another pull. then take it over to james and let him Port/Polish and Delta Cam it then Pull again..

I ran my setup on a dyno last summer to see what it was putting out. The best that I could get from it was 198 Hp and 298 Foot pounds. When we went to the track with it my son ran a 14 sec flat at 99.8 mph in the quarter mile. I am still trying to figure out why the car is running rich, I read a thread here on the forum about the effects that after market O2 sensors have on performance and plan on replacing mine with a genuine GM O2 sensor to see if it has any effect. Will post results when I get them.

Joe Sokol

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85 SE 2.8 - beater coupe-
86 SE 3.4 -in progress 3800 II SC -
88 Formula GT 4.9 5 speed beast
Enough parts outside for another one
-And a 3.4 push rod for sale in the mall Go and look-

quote Originally posted by markviiisvt4: or I could whip you up one of these that i'm workin on for the 4.9

That looks awesome! I would defenatly be interested in something like that.

I'm hopeing to get my car on the dyno sometime within the next month. I have a friend that works at the local College where they have a dyno. Trying to work something out right now.

quote Originally posted by Steven Snyder: That box on the right side of the intake plenum... is that a MAP sensor cover?! That looks trick!

Yes it is. I like it. Hides the MAP sensor pretty good.

Here is what you need:

It's on Ebay for $10 and the seller is a good guy!
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=8026935325&sspagename=STRK%3AMESE%3AIT

quote Originally posted by FieroMaster88: Yes it is. I like it. Hides the MAP sensor pretty good.

Where do you get one? Did it come stock on the Allante?

quote Originally posted by Fastback 86: Where do you get one? Did it come stock on the Allante?

Yes, it came stock on the Allante.

Hey I've got a 4.9, and would like to know exactly what's needed off the Allante engine to use the Allante's intake?

Do you need both the Upper and Lower Allante Intake manifolds? Or just the Upper?

Thanks,

Matt
88gt
88formula(4.9 project)
88coupe(parts)
Dayton, OH

quote Originally posted by Modat5: Hey I've got a 4.9, and would like to know exactly what's needed off the Allante engine to use the Allante's intake? Do you need both the Upper and Lower Allante Intake manifolds? Or just the Upper? Thanks, Matt 88gt 88formula(4.9 project) 88coupe(parts) Dayton, OH

You need both the lower and upper intake manifolds. You will also need the fuel rail. If you have a complete Allante engine to get parts from you should get the rocker arm supports since they are steel. They are aluminum on the 4.9.

Thanks FieroMaster88!

That's exactly what I need to know.
Thanks again,

Matt
88gt
88formula(4.9 project)
88coupe(parts)
Dayton, OH

quote Originally posted by Modat5: Thanks FieroMaster88! That's exactly what I need to know. Thanks again, Matt 88gt 88formula(4.9 project) 88coupe(parts) Dayton, OH

No Problem.