Well I was scanning the neon boards and they have succesfully adapted the throttle body off of a 4.0L Jeep engine to their 420a. Its 60mm and with a p/p intake manifold said the result was beautiful. I dont know if this write up would work for us but this is what they did (got it from www.neonspeedlab.com):

Tools/Supplies Needed:
Throttle Cable bracket (stock neon part)
Aluminum Bracket on '97-'99 Neons that holds the TB to the head
TB shaft from the stock Neon piece
Spring from a Neon TB
Neon TPS and IAC
Jeep Cherokee TB

*PICTURE BELOW FOR REFERENCE OF PARTS (COMING SOON)
*PRINTABLE VERSION OF THIS SECTION LOCATED AT THE BOTTOM OF THE PAGE

STEP 1: Altering the Jeep TB

1: You will have to remove the bullet on the end of the Cherokee IAC and install it on the end of the NEON IAC so that it will seal properly. The IAC on the Keep TB will also have to be turned 180 degrees so that it will not hit the intake manifold. Also I would use lock washers and some silicone on the gasket that goes between the IAC carrier and TB.

2: Use the NEON TPS

3: Remove the Cherokee TB shaft and butterfly. You will use the butterfly on with your setup. The rest you can do with as you please. You will need to cut the slit that the butterfly fits in so that it will accept the 60mm butterfly from the Cherokee t/b.

4: You will need to cut the end of the carrier-the plastic part so that the butterfly can be centered when installed in the Cherokee t/b. You will have to just eye it and cut a little at a time.

5: Once you are done with this you'll have to cut a few coils off the neon throttle return spring and use this spring on the Cherokee t/b to close the butterfly.

6: There are a couple of other things that will have to be cut on the neon carrier-they are pretty obvious.

7: You will have to come up with your own throttle stops. I used sheet metal for the one stopping the t/b when it closes. And I used a small allen screw on the other side so that it doesn't open too far when you to wide open throttle.

8: The mounting holes on the Jeep TB will have to be enlarged so that you can use the mounting position on the neon intake manifold. You also may have to open the manifold a bit with a Dremel.

9: The IAC opening on the manifold will have to be filled since you won't be using it anymore. Also you will have to make your own gasket, which can be done by purchasing a sheet of gasket material from your local parts store, and cutting it accordingly. You need to add about a foot of wire to each of the Neon IAC motor wires so they will reach the Cherokee TB's IAC location.

I doubt it would work because the 420a in the eclipse and neon have completely different intake manifolds, so I doubt the jeep TB would mate to the eclipse intake manifold.. but I suppose if you took pictures and compared a neon and a 2gnt.. then perhaps they do mount the same.. but i really doubt it.

yeah, i figured that might be a problem, but I thought maybe one of the experts we have on this board might be able to do something with it. Hell someone needs to find out for sure whether or not we can use them. One guy on the neon board bought and modified the throttle body for like 50 bucks, thats cheaper than gettin ours bored out to 55mm by Howell.

nope, if it'll work on a neon, it wont work on a eclipse 420a... the throttle linkage is on the opposite side... dont think it could be adapted to work

http://www.modernperformance.com sells a 60mm TB for a Neon and I spoke with them a while back about getting one adapted for an Eclipse. However, they were not interested...



Eric Madden

I know its a bit smaller but why not just buy the 55mm TB at http://www.machv.com/newovthrotbo.html.

But then again, doin the work youself is half the fun.

Happy Cruisin

well this one wont work anyway, i guess ill just buy a used tb and get it bored out at howell

This post seems a little "BORE"-ing to me. Just bore an extra throttle body out. It works and is flawless, no worries with compatibility.

exactly.. and the price isn't that bad.. and it's basically a new TB.

I posted this for a couple of reasons 1) people were always wondering whether or not the throttle body from the chrysler engines would fit our cars and this helped to answer that question and 2) if it were possible a 60mm tb with a p/p intake manifold would give greater results than a 55mm tb could ever give. So boring or not I found it to be a worthwhile post and now that I know its not possible I see a 55mm tb in my future.

i think he was just messing with ya man... yeah a 60mm would be tite.. but all i know of is the 55mm...

The 55mm is like 300 bucks, so Does anyone know what it would cost to get stock bored out to 55mm, and have oversized plate installed? Just want to compare to see if I took the wrong road. Also has anyone gotten any extrude-hone work done? What parts and what did it cost ya?

Happy Cruisin

www.howellautomotive.com bores TB's and installs the larger butterfly valve to your stock TB for $100.
current status unknown

http://hometown.aol.com/ohshootuhh/

Perf:
KYB AGX Struts
Neuspeed Sport Springs
5 Strut Bars (2 F/U, F/L, R/U, R/L)
Sprint Front Camber Kit
$15 Rear Camber Kit
Corbin's A/F Gauge
MSD DIS-2 Ignition System
Some Regrind Cams that need High Compression (which I don't have)
Ported Intake Manifold
Ported Throttle Body
Nameless Cold Air Intake with a K&N Filter
Custom 2 1/2 inch exhaust with Dual DTM Muffler
Empty Catalytic Convertor
Energy Suspension Motor Mount inserts
Hurricane_GS Short Shifter
Symborsky Shift Kit
Clutchmasters Stage 3 Modular
225/50/16inch Wheels and Tires


Audio:
Alpine CD Head Unit
Alpine Flex4 25W X 4 for Fronts and Rears
Alpine V-12 450W X 1 for Subs
Infinity Reference Series 5 1/4 and 1 inch tweeter component systems for fronts and rears
Blaupunkt 3 way 6x9's in the rears
3 MTX 5000 10" 12 ohm subs running 4 ohms mono

by the way.. if I remember correctly.. Howell doesn't actually do it.. they are just a distributor... they are built by AF/X http://www.afxmfg.com/ check out there site if you haven't already. they are the people that made almost all the stuff for my 420a SOHC.

what? 420A SOHC?

-Tony 98'GST



http://eclipzgst.dyndns.org
AIM: YNOT420247

The neons had 420A SOHC and DOHC
current status unknown

http://hometown.aol.com/ohshootuhh/

Perf:
KYB AGX Struts
Neuspeed Sport Springs
5 Strut Bars (2 F/U, F/L, R/U, R/L)
Sprint Front Camber Kit
$15 Rear Camber Kit
Corbin's A/F Gauge
MSD DIS-2 Ignition System
Some Regrind Cams that need High Compression (which I don't have)
Ported Intake Manifold
Ported Throttle Body
Nameless Cold Air Intake with a K&N Filter
Custom 2 1/2 inch exhaust with Dual DTM Muffler
Empty Catalytic Convertor
Energy Suspension Motor Mount inserts
Hurricane_GS Short Shifter
Symborsky Shift Kit
Clutchmasters Stage 3 Modular
225/50/16inch Wheels and Tires


Audio:
Alpine CD Head Unit
Alpine Flex4 25W X 4 for Fronts and Rears
Alpine V-12 450W X 1 for Subs
Infinity Reference Series 5 1/4 and 1 inch tweeter component systems for fronts and rears
Blaupunkt 3 way 6x9's in the rears
3 MTX 5000 10" 12 ohm subs running 4 ohms mono

Call it irony but AF/Xs address and Howells address are the same...hmmm ;-)



Eric Madden

that's funny.. but AF/X is the actually company that makes that stuff. and yeah.. i had a 420a SOHC in my 97 Breeze.. it pushed about 137hp stock.. not bad at all.