Make and post your own poster here http://www.fiero.nl/forum/Forum1/HTML/076072.html

[This message has been edited by fierosound (edited 05-26-2009).]

quote Originally posted by N3M3S1S : Super Duty 4 engine - w/ Edelbrock valve cover, Edelbrock 4-bbl intake and carb How well does she haul ass, anyway? I've wondered that.

Hard to say. I've gotten "used to it" so it doesn't feel fast to me anymore. It feels about the same as my 3.4L supercharged engine, but that a manual, this is an auto. Others who've ridden with me say it's "damn fast".

Idles rough - with intake valves over 2", high lift cam and huge ports, this engine is made to REV. It doesn't sound like anything else. Hard to describe.

I changed to a smaller 400cfm Carter carb from the Edelbrock 500cfm (it was just too big). The Carter seems to be jetted pretty good now and the engine responds extremely well. It drives pretty good and doesn't feel like a 4-cylinder at all. Gets up to speed pretty quick, acceleration for passing is great (unlike a stock Duke which makes more noise, but doesn't "pull"). Terrible mileage in city (likely because I'm booting it all the time ) but seems much better on the highway. The smaller gas tank of the 84 is really noticeable.

The 3.73 4-speed auto feels really good. It stays in 3rd until almost 50mph before shifting into 4th for cruising. The TCC lockup helps as it drops the rpm by about 200. I think I could adjust the TV cable to have 4th come in sooner, but I think that would lug the engine. A 5-speed manual would have been more fun

With only about 1200 miles, it isn't quite broken in yet. At least not enough for me after spending those big $$$ rebuilding it. I want to get a few more miles on it before I switch to synthetic oil and that should help with power. I had it on a dyno last year with the 500cfm Edelbrock carb and it looked like 160hp at the wheels at that time, but I think the engine is making more power with the Carter carb now.

I don't think it will set any 1/4 mile speed records at the track, but I think people will still be blown away that it's "that fast with a 4-cylinder" and that it's a World of Wheels car at the track.

[This message has been edited by fierosound (edited 03-18-2010).]

I decided to convert the Indy to a manual transmission.
The automatic transmission in the Indy doesn't do justice with the SD4 engine.
The engine really wants to rev and a Getrag 5-speed manual transmission would give me much better control of its power.

Have a Service Manual handy when you do this
http://fieroinfo.com/manuals/

If you just bought your $500 Fiero and wished it were a manual, you'd be better off selling it and buying another with the manual transmission.
But if you already have a lot of work and money into your car, IT IS WORTH making the swap.
There is a tedious amount of work involved, but it is mostly the "remove and replace" variety.

Converting to a manual requires all these parts from your donor.
tranny
axles
shifter assembly
2 shifting cables
clutch pedal assembly
hydraulic clutch line
master cylinder
slave cylinder
flywheel
clutch set <---- buy new - no reason using a worn one
Plastic frame with boot to cover shifter assembly


Dropping the cradle and swapping the transmissions and axles is basically staightforward, so I'm not going to cover that in detail here.

Of course, you need to change the flexplate to the correct flywheel for your engine (85-87 V6 or 88 V6, or 4-cylinder) and install your clutch set.



The hydraulic system is tedious to install. You should pull the front spare wheel tub and gut the interior
(at least the driver's seat, upper steering column, and center console including "plastic skeleton").
I pulled the cluster and dash as well to see better.

The automatic pedal box is held in by the 4 bolts that hold the brake booster (plus one under the dash).
The manual pedal box with the clutch will in addition have the two studs for the clutch master cylinder.
The firewall will have a sheet metal plug that can be popped out for installing the master.



Remove the automatic transmission cooling lines and install the hydraulic clutch line in it's place. It bolts in using the same bolts into the same locations.
Maneouvering the line into place past the steering column and brake booster can be done more easily while the brake booster is unbolted from the firewall.



The clutch slave will attach to the transmission using its normal bracketry.



With the "plastic skeleton" out of the center console, it's a simple matter to remove the park/lock cable from the shifter to the steering column.
I left the steering column as is and didn't bother with modifying it to add the key latch.



You can now easily remove the automatic shifter and shift cable and install the manual shifter with shift and select cables.

I installed a Getrag 5-speed. This is the revised cable routing for this transmission http://www.meisners.net/fiero/TSB/TSB88714.htm

[This message has been edited by fierosound (edited 11-22-2025).]

------------------

DONE: 86gt 5 speed 4.9 complete rebuild with buds outback northstar pistons , delta cams E303 cam , full ported , polished , stronger head springs, and flow tested heads and manifolds. rockcrawl's custom chip , polished crank . too much to list

86 gt 350 4 speed
85 t-top BEING PARTED
86gt 4.9 highly modified
86 and 87 fiero database www.geocities.com/cwandall/fiero.html

The transmission swap is done!!

Guys with Dukes - if you need a new flywheel and flywheel bolts - start looking early. There may be some searching/waiting for parts involved.
It seems Dukes were mated to manual transmissions only in Fiero, Chev S10/S15 and Jeep CJ/YJ - all other Pontiac/Buick/Olds were predominately equipped with automatic transmissions.

Stock flywheels are discontinued by GM, but Sachs makes them http://www.autopartswarehou...bal&N=0&Ntt=flywheel

The big "wait time" was getting the V6 Fidanza aluminum flywheel welded and redrilled for the SD4 crank (Duke pattern).
Mostly time sitting on the shelf "waiting for my turn" because it didn't take long once they got to it.

The SD4 crank was also "pinned" in it's previous life as a race engine. In addition to the 6 flywheels bolts, 3 steel pins are
embedded in the crank and line up with holes in the flywheel. These take the shear loads off of the flywheel bolts.



After the original holes were welded up, and both faces machined, 9 holes were drilled in the flywheel to match the crank's face (used old flexplate as template).
Center hole is also larger than on a V6 and was machined to match the crank.

Stock flywheel bolts have huge low height hex heads (M10 x 1.5 x 23mm) and couldn't be found locally. I purchased ARP flange head bolts PN 134-2201 instead.
These are 25mm long and need to be cut down in length to 23mm as they bottom out in the crankshaft holes otherwise.
The flywheel bolt holes were countersunk for the flange on the head and work much better.



The Spec Stage 2 clutch pack was then attached.
Blue Locktite is a necessity on the flywheel and pressure plate bolts (just to be safe)



Wiring harness changes from removal of transmission gear selector switch were fairly straightforward. (these are all over PFF)
- shorten wires for VSS
- install a new connector for backup light switch
- power wire bypass to firewall connector



The rest of the assembly is straightforward. Bolt on the transmission, put the engine/tranny back on the cradle and install the drive axles.
I forgot to take a picture of it all on the cradle. DOH!!

I installed a rebuild kit in the clutch master cylinder - Wagner PN F110274.
In addition, I cut the pushrod and threaded it for a 5/16" thread long nut and locknuts to make it adjustable.



The rest of the install is unexciting. Here's the clutch master cylinder in the car.



The select/shifter cables clear everything reasonably well.
The bracket for the shifter cable sits fairly high, but a new coolant hose has a long enough end to clear it.
The slave cylinder is more easily accessible than in V6 applications - no exhaust crossover in the way!



I now have 3 pedals were I only had a brake and gas pedal before.
Wiring in the clutch and cruise switches was VERY simple.



... and I installed an 84 short shifter and Getrag 5-speed shifter surround.



I changed all my bezels to brushed silver ones - to match the gauges and shifter plate.
(STILL looking for a silver manual shifter surround in MINT condition)

I got a recovered leather shift knob from mmeyer86gt/gtp (excellent value!!)
http://www.fiero.nl/forum/Forum4/HTML/047955.html

Later I replaced the boot with a short shifter one from Rodney
http://rodneydickman.com/pr....php?products_id=236

[This message has been edited by fierosound (edited 01-25-2024).]