Rebuild of Indy Fiero #163 Super Duty 4 (Page 10/29)
fierosound JAN 19, 11:12 AM
I have installed the 400cfm Carter 9410 Super-Quad 4-barrel carburetor (designed for GM 3.8L V6 engines).
This replaces the Edelbrock 500cfm which was just too big for this 3.3L SD4 engine.

I installed a divider plate in the intake manifold. This will increase the vacuum signal to the carb by changing
it from an “open plenum” to a “divided plenum” and should make low RMP throttle response crisper.



With the divider, you also require a base gasket with the divider down the center as well.



Here’s the carb installed. There’s no easy way to get a highly polished finish like the Edelbrocks (they have a 10 step process),
so I painted the main body aluminum and the upper portion gloss black (basically the reverse of marine carbs).
The paint will seal the pores of the aluminum so the carb won’t get stained from gas, oil and engine grime. It looks pretty good.



I have set the idle speed and mixtures and check and adjust the throttle response.
The carb seems to be working well. I have a steady 1000rpm idle, seems smoother than before too.
When blipping the throttle you can see the the secondary air valve open and fuel from the nozzles shooting in.
I think this will be a BIG "night & day" improvement in driveability.

I think because the Edelbrock 500cfm was too big the secondaries never opened up properly AND it basically ran as a
2bbl that was too small at the upper RPM band and so the engine leaned out as the RPM went up. Shouldn't have that problem now.

I was able to get it out for a short test drive and it's quite driveable with the new Carter carb.
It drove well and I could DEFINITELY feel this carburetor WAS working much better than the Edelbrock,
but I won't be able to fine tune for WOT performance and such until later once all the snow is gone.

[This message has been edited by fierosound (edited 09-02-2023).]

85LAMB JAN 22, 01:46 PM
WOW.....!!!

You have done a great job rebuilding the car.
Thanks for posting your build thread its very helpfull and inspirational, so that I get to work on my own car.
I wish I could give you another plus.

Keep up the great work and please continue to post
fierosound FEB 11, 12:18 PM
Thanks 85LAMB

I have it driveable and it feels pretty good with the new carb, but fine tuning can't be done until all the roads are clear and the weather is warmer a couple of months from now.

Official "Public Unveiling" of my Indy is coming up at World of Wheels Feb. 20-22 in Calgary. I'm curious/nervous about the response, but I know people/kids were waving (favorably, thumbs up, etc) when I drove down the street with the thing, so I think people will be "wow'd". I know virtually nobody has ever seen a Fiero Pace Car in this city, so I expect a lot of questions.

Our Club is putting in 6 cars in total, including a second all stock Indy next to mine, my 3.4L supercharged 87 GT, a blue 87 GT, burgandy 87 2M4 and red 85 GT.

Both B-J convertible prototypes are also expected to be there in a separate display. http://www.fiero.nl/forum/F...1/HTML/074154-2.html

[This message has been edited by fierosound (edited 02-11-2009).]

Erik FEB 11, 12:36 PM

quote
Originally posted by fierosound:

I have installed the 400cfm Carter 9410 Super-Quad 4-barrel carburetor (designed for GM 3.8L V6 engines). This replaces the Edelbrock 500cfm which was just too big for this 3.3L SD4 engine.

I installed a divider plate in the intake manifold. This will increase the vacuum signal to the carb by changing it from an “open plenum” to a “divided plenum” and should make low RMP throttle response crisper.


[




Cut a little notch out of the divider plate to balance it
Kento FEB 11, 12:42 PM

quote
Originally posted by 85LAMB:

WOW.....!!!

You have done a great job rebuilding the car.
Thanks for posting your build thread its very helpfull and inspirational, so that I get to work on my own car.
I wish I could give you another plus.

Keep up the great work and please continue to post



How is your Kit progressing????
85LAMB FEB 11, 01:12 PM
Kento
Check PM
fierosound FEB 11, 01:16 PM

quote
Originally posted by Erik:

Cut a little notch out of the divider plate to balance it



Not necessary. The plate isn't completely to the ends or the bottom.

fierosound FEB 17, 11:48 AM
[

There's a head and a couple of these intakes on eBay. They'll fit a stock 2.5 Iron Duke engine.

http://cgi.ebay.com/ebaymot...C39%3A1%7C240%3A1318

http://cgi.ebay.com/ebaymot...C39%3A1%7C240%3A1318

http://cgi.ebay.com/ebaymot...C39%3A1%7C240%3A1318

[This message has been edited by fierosound (edited 02-17-2009).]

KurtAKX FEB 17, 05:33 PM

quote
Originally posted by fierosound:

There's a head and a couple of these intakes on eBay. They'll fit a stock 2.5 Iron Duke engine.



I am bidding on both of those intakes currently for my Super Duty head.

Three things though.

1) the intakes don't fit a stock head, only a super duty head.

2) The heads don't fit a stock block without machining. The heads are setup for 1/2" head studs, whereas stock Iron Duke studs are 11mm.

3) That head is pretty much at the end of its useable life. It has .170" machined off of it already. There's no more material left to do a clean up cut on the deck surface. Its milled so far one of the bolt holes is actually protruding into the deck surface now. Aluminum castings can be welded on (unlike iron), and there are even hard aluminum filler rods used specifically for repairing the deck surfaces of cylinder heads, but it would be in the neighborhood of $1500 worth of head work to restore some deck material.


From an email I received from the guy doing my SD head:

quote

".170 is huge the head you have is only cut .100
and as far as welding the deck yes it is possible if you have a huge pocket book and they don't make them or cant find them anymore. Not really an option.


Brad Beaubien
Roush Cylinder Head Dept."
h.d.fire FEB 19, 05:31 PM
Tony-
Beautifull car!
You've done an excellent job on this build, I hope to get the chance to see your Indy in person some day.

------------------
84' Indy Pace Car (car #2000)
86' G.T.
87' Coupe (daily driver)
88' Formula (V8 project)
Member: NIFE