As some of you know, my V8 Fiero project has been on hold a while now due to a blown 5-speed Getrag transmission. I've been debating on which transmission to replace it with, and for a while I was sold on the idea of using the G6 6-speed. However, after giving it some more thought, I am starting to lean towards using a beefed-up automatic transmission instead. Above all else, I want to have a transmission that will stay together under the V8's torque for street and occasional strip duty. The Getrag was just way too brittle (and geared wrong) for my taste/driving style.

I much prefer driving a manual transmission, but in all honesty, I will happily install the auto just for the sake of durability and peace of mind. The problem is that I have very little knowledge or experience with the Fiero's auto transmission, let alone modifying one... So I'm looking for is some advice and information regarding swapping out my 5-speed for an automatic.

First of all, will the Fiero automatic transmission "bolt up" to my existing V8 Archie adapter?
What are the most common street/strip modifications for this transmission?
Who sells these transmissions street/strip ready, or will at least build one which is?

I would really love to hear from some of you guys you have some experience with this swap and/or transmission...

Thanks in advance,

Brett

Get a 65E with some hard parts and you are set..........

quote Originally posted by ITALGT: First of all, will the Fiero automatic transmission "bolt up" to my existing V8 Archie adapter?

No, you will need the adaptor plate for an auto that Archie sells, and the flexplate adaptor piece as well. Will have to modify the Fiero flexplate a little to fit the 4T65E-HD torque converter on it. The whole package gets very wide. I had to not only cut the frame a little but also cut the engine cradle just a bit on the drivers side, but it does fit. You can see details of all this on my swap site. Oh, you'll need some sort of transmission controller as well.

The exhaust is also a little bit of a challenge at the rear since the tranny comes very close to header.

Rick
www.wheeltimesolutions.com/Dineroproject

[This message has been edited by couldahadaV8 (edited 07-16-2010).]

It is possible you can make a transmission controller out of a few sensors and a stock 65e PCM.

I have a 4T65e-HD with 18K miles on it from a 2007 LS4 if you are looking for a transmission (it is on ebay). It has the tranny mounted starter, so you would not need the oil filter relocation kit.

It hasn't been mentioned yet, but the Zumalt style adapter plate (from Steet Dreams) is about 5/8" thick and would save alittle less than 1" of clearance on the passenger frame rail vs. the Archie automatic adapter plate. It would require cutting the OEM starter pad off the block to clear the tranny, but might save you from some frame clearancing on the passenger side.

[This message has been edited by fieroguru (edited 07-16-2010).]

Thanks for the info guys... sounds like converting over to an auto may be more involved than I first thought!

If I cannot use my existing adapter, then I may have to forget about the auto swap altogether.

I have a 4-speed that I could put in, but that would put me back where I started. I can't tell you how frustrating it is to have horsepower on tap but not being able to put it to the ground. I babied the Getrag for about 3 years before it finally let go during a non-aggressive launch at the drag-strip. I really don't feel like going through this again!

Brett

Have you tried a rebuilt getrag or the 92-94 HTOB version with the stronger differential? Results vary widely on the SBC running used high mileage trannys, you best bet would be starting with a rebuilt one.

Only other option would be the F40... but that will be more expensive than installing a rebuilt getrag, especially if you are not a machinist/metal fabricator.

Are you sure the good diff was '92?

I would rather invest the +/- $3.5K (Asuming bolt on Archie kit) in installing a brand new 6-speed than any rebuilt getrag. Then buy new spares for $550.

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Red: TPI V8 + 6-Speed Yellow: Nitrous 3.4 + 5 speed
304rwHP/366rwTQ

quote Originally posted by darkhorizon: It is possible you can make a transmission controller out of a few sensors and a stock 65e PCM.

Wasn't that a MacGyver episode?

quote Originally posted by Alex4mula: I would rather invest the +/- $3.5K (Asuming bolt on Archie kit) in installing a brand new 6-speed than any rebuilt getrag. Then buy new spares for $550.

Alex, that seems to make some sense... and I like the idea of having a spare transmission on hand. I have basic fabrication skills and I can also weld, so I'm not that scared of the actual conversion, but money is tight right now to say the least. The other problem I have is that I don't have all the right tools and equipment to complete the conversion...

The last few of my 282 cars that have left the shop, have all broken driveline parts.. but just not the transmission itself. Both were fresh boxes with upgraded differentials.

Both are making more power/torque than your v8.

quote Originally posted by darkhorizon: The last few of my 282 cars that have left the shop, have all broken driveline parts.. but just not the transmission itself. Both were fresh boxes with upgraded differentials. Both are making more power/torque than your v8.

...were these parts letting go at the strip or under "normal" driving conditions?

Brett

[This message has been edited by ITALGT (edited 07-17-2010).]

quote Originally posted by Isolde: Are you sure the good diff was '92?

Some were available before then (possibly as early as 89), but the 92-94 getrag (also called the NVG-550) all had them.

quote Originally posted by Alex4mula: I would rather invest the +/- $3.5K (Asuming bolt on Archie kit) in installing a brand new 6-speed than any rebuilt getrag. Then buy new spares for $550.

Does that $550 include shipping? If not, I have a better source, assuming you're in the 48 states. Also, fieroguru has a good thread showing how to attach an F40 to a sBC for far less $ than the kit, and with a far lighter flywheel, plus it fits in the car with more clearance at each end. He shows everything, but for axles I'd just get measurements then call the DriveShaftShop for a set of custom-length Stage 2 Cobalt SS axles, at $800/set. They're rated higher than the F40, and they;re stronger than they're rated, but DSS also offers stage 4 axles if you'd rather frag the trans than the axles. If you expect to break very many F40s, then just start with a cryo'ed NSX 5-speed. There's video evidence out there of these withstanding 1000 rwhp on sticky tires.

[This message has been edited by Isolde (edited 07-17-2010).]

quote Originally posted by Isolde: Does that $550 include shipping? If not, I have a better source, assuming you're in the 48 states. Also, fieroguru has a good thread showing how to attach an F40 to a sBC for far less $ than the kit, and with a far lighter flywheel, plus it fits in the car with more clearance at each end. He shows everything, but for axles I'd just get measurements then call the DriveShaftShop for a set of custom-length Stage 2 Cobalt SS axles, at $800/set. They're rated higher than the F40, and they;re stronger than they're rated, but DSS also offers stage 4 axles if you'd rather frag the trans than the axles. If you expect to break very many F40s, then just start with a cryo'ed NSX 5-speed. There's video evidence out there of these withstanding 1000 rwhp on sticky tires.

Interesting... haven't heard of using the NSX 5-speed before... anybody out there have one in a V8 Fiero? Isolde, thanks for sharing the above info... I think I will take a closer look at fieroguru's thread and take some notes. Great information by the way!

Brett

quote Originally posted by darkhorizon: It is possible you can make a transmission controller out of a few sensors and a stock 65e PCM.

I know of a guy who made a trans controller for his 4T60 out of a Duke ECM feeding in the TPS, ETS, MAP and speed inputs. His application was only used for the TC lockup function but a PCM with the proper sensor inputs should be able to shift the 4T65e. It will probably throw DTC codes but these can be turned off in the programming. Never tried it but it all sounds very logical.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

You will need the diff adapter plate. Newer auto trans are better. I tried a bunch of fresh built TH125s that were beefed up to the maximim by a shop the builds transmissions for drag cars. I never got more than 1,000 miles driving it on the street before bands and clutches were fried. I never even did a burnout with it. They went just cruising down the freeway.

quote Originally posted by ITALGT: Interesting... haven't heard of using the NSX 5-speed before... anybody out there have one in a V8 Fiero? Isolde, thanks for sharing the above info... I think I will take a closer look at fieroguru's thread and take some notes. Great information by the way! Brett

West Coast Fiero offers a way-overpriced kit to do the NSX trans. If anyone's running one, they'd know who. Later NSXs were 6-speeds, but the 6-speed isn't as strong. And you might find first gear nearly useless in either version, since they were tiny engines spinning 8000 rpm. But it is a strong trans.

quote Originally posted by ITALGT: As some of you know, my V8 Fiero project has been on hold a while now due to a blown 5-speed Getrag transmission. I've been debating on which transmission to replace it with, and for a while I was sold on the idea of using the G6 6-speed. However, after giving it some more thought, I am starting to lean towards using a beefed-up automatic transmission instead. Above all else, I want to have a transmission that will stay together under the V8's torque for street and occasional strip duty. The Getrag was just way too brittle (and geared wrong) for my taste/driving style. I much prefer driving a manual transmission, but in all honesty, I will happily install the auto just for the sake of durability and peace of mind. The problem is that I have very little knowledge or experience with the Fiero's auto transmission, let alone modifying one... So I'm looking for is some advice and information regarding swapping out my 5-speed for an automatic. First of all, will the Fiero automatic transmission "bolt up" to my existing V8 Archie adapter? What are the most common street/strip modifications for this transmission? Who sells these transmissions street/strip ready, or will at least build one which is? I would really love to hear from some of you guys you have some experience with this swap and/or transmission... Thanks in advance, Brett

you could find a regular 4t60-HD from a 1990 cadillac or from an 87-88 caddy allante, as it uses a TV cable and isn't shifted by the ECM. they are easy enough to beef up me thinks. they already handle low end TQ really well....then you wouldnt have to worry about clearence issues on the driver's side, since it is sligjhtly smaller than the 4t65e, AND you wouldn't need a transmission computer....

What exactly is involved with machining the flexplate and what is the flexplate adapter?

I have been think of swapping to an auto and haven't found much on using the 4t60. thanx Ray

quote Originally posted by stickpony: Alex, you have a v8, how can you even stand the 1st gear in the 6 speed? it is almost a useless gear....i REALLY wish someone would come up with a better final drive for that tranny to swap in for people attaching them to V8's...if the final drive could just be dropped to about 3.0:1 or taller, it would be SO much better....

Changing the FDR isn't the best solution, changing first gear is. That'd increase the torque capacity, and besides, most performance-cammed 350s wouldn't like any less cruise rpm than 6th gear already offers. Not only that, but the rpm drop on the 1-2 upshift is excessive.

[This message has been edited by Isolde (edited 07-18-2010).]

quote Originally posted by rcp builders: What exactly is involved with machining the flexplate and what is the flexplate adapter? I have been think of swapping to an auto and haven't found much on using the 4t60. thanx Ray

The flex plate adapter is used with the Archie auto kit to allow bolting a stock fiero 4 cyl flex plate to the SBC crankshaft and to make up for the thickness of the adapter plate. Rick did a pretty good job domumenting the modifications to the flex plate to it would clear the 4T65 torque converter in his build thread:
http://www.wheeltimesolutio...ero_project___page_6

If you use the Zumalt based kit, there is no flex plate adapter, the flex plate bolts directly to the SBC crank. The way I have done this in the past is to take a SBC flex plate and turn it down so the smaller ring gear will fit over it, set the proper ring gear depth and then weld the ring gear to the SBC flex plate. All of this and more is detailed in my 4.3 / 4T60 build thread here:
https://www.fiero.nl/forum/Forum2/HTML/087174.html

quote Originally posted by fieroguru: The flex plate adapter is used with the Archie auto kit to allow bolting a stock fiero 4 cyl flex plate to the SBC crankshaft and to make up for the thickness of the adapter plate.

fieroguru, Please don't take this as a negative post. I normally don't critique your posts because the information in your posts is typically more accurate than anyone else that I can think of.

However, I'd like to clairify a little information.

When I designed my kits, the thickness of the adapter plates was the last thing to be determined. On both the autopmatic kit & the stick shift kit, I assembled the parts that were needed to be stacked up inside the bellhousing & that determined the adapter plate thicknesses.

The other criteria that was used when designing my kits was that the componets used had to be available to the average home builder & had to be universal enough that they would work for all SBC's. Keeping in mind that the average home builder doesn't have a milling machine, a lathe or any other machine tools in his garage to make his own pparts with.

Yes the (J. D. Michael kit) aka Zumalt kit used a thinner adapter plate on his automatric kit. But remember that to keep the torque converter from going too deep into the 125C bellhousing the person putting it together had to grind of the heads of the flex plate bolts.



Because of the shape of the flexplate side of the Torque converter & the fact that it contacts the heads of the flex plate bolts, you must shave the bolts heads to keep the torque converter from being too deep into the bellhousing. Being too deep into the bellhousing will result in cracks caused by the torque converter being shoved into the back of the b-housing.



I know that you've read it, but anyone else that would like to review more on this topic can review the 1st couple of pages of this thread https://www.fiero.nl/forum/A...040710-2-019134.html

Thanks

Archie

[This message has been edited by Archie (edited 07-18-2010).]

quote Originally posted by Archie: fieroguru, Please don't take this as a negative post. I normally don't critique your posts because the information in your posts is typically more accurate than anyone else that I can think of. However, I'd like to clairify a little information.

No offense taken, I know there are issues with the original zumalt design. In my 4.3 thread (linked to above) I specifically discuss the crankshaft bolt issue and provide my solution w/o grinding the crankshaft bolts (I added spacers so the adapter plate has an effective thickness of about 3/4".

quote Originally posted by fieroguru: Here is the crankshaft bushing to support the torque converter: With the torque converter just sitting on the flex plate, there is a 0.13" gap between the flex plate and the mounting tabs on the torque converter. This space is due to interferance between the crankshaft bolts and the center contour of the torque converter. I spun the torque converter around while sitting on the crankshaft and here you can see the scratch mark from the crankshaft bolts: One way to eliminate the interferance and resulting gap is to round off the outer edges of the crankshaft bolts. Another way is to just use a 0.13" spacer to close the gap without needing to modifiy the crankshaft bolts. I will be using the spacer method, but understand that the reason this is possible is due to the adapter plate thickness I am using. With the torque converter fully seated in the tranny and using a ruler accross the bellhousing face... 0.57" is the distance from the face of the transmission bellhousing to the face of the torque converter mounting tabs. If the torque converter tabs are further than this from the adapter plate - bad things will happen. With the torque converter resting on the crankshaft bolts... 1.16" is the distance between the SBC bellhousing face and the torque converter mounting tabs. 0.70" is the thickness of the adapter plate So 0.46" is the distance from the adapter plate to the face of the torque converter mounting tabs. There is 0.11" of clearance for this swap with using the 0.13" spacers and no need to round off the edges of the crankshaft bolts. CAUTION - the reason this works for me is the 0.70" adapter plate thickness. The adapter is actually 0.58" thick, but I used spacers to make it 0.70" thick. This gave me an extra 0.12" of room which provided the space needed to use the 0.13" spacer. If I had just used the 0.58" adapter, the adapter plate to torque converter mounting tabs would be 0.58" which is further than the 0.57" of room within the tranny, causing a bind and eventually leading to bad things. Next step is to make the needed spacer. That will be a project for Saturday!

[This message has been edited by fieroguru (edited 07-18-2010).]

Hey guys, after reading through the above posts I am reminded once again of why I love this forum so much... thanks again for all the great input and discussion!

I really wish money was not an object (as most of us do)... if it was really up to me, I would be building a stretched Fiero w/ a Porche or Audi transaxle... but I'm starting to really getting off track here. What I would like to do is get this Fiero back on the road without big spending big $$$, which for me rules out the 6-speed and the automatic.

Aside from laying off the throttle a bit (and avoiding hard launches at the drag strip), what other things can one do to improve a 4 or 5-speed's durability? I know some basic things like a rebuild, running a good synthetic lube, etc will be beneficial... but what else can be done (or has been done) to these transmissions to make them more durable?

I almost need to start a new thread now... lol...

Brett

I believe cryo treatment of the gear set, and sometimes the case, is effective for that. These guys will apparently do a set for $75.

http://www.cryoplus.com/prices.html

The guys on RFT seem to think that the F23, also known as the Getrag 287, is at least as strong as the '93-'94 Getrag 282, and it takes the same axles. The 282's ratios are better. The 287 is said to have much smoother shifting.

[This message has been edited by Isolde (edited 07-20-2010).]

quote Originally posted by ITALGT: Aside from laying off the throttle a bit (and avoiding hard launches at the drag strip), what other things can one do to improve a 4 or 5-speed's durability? I know some basic things like a rebuild, running a good synthetic lube, etc will be beneficial... but what else can be done (or has been done) to these transmissions to make them more durable?

A properly rebuilt getrag will last quite a long time. I do not know the Hp/Tq levels of your application, but mine was 283whp/317wtq and I put 40K miles on my swap between the Isuzu/highmileage 92-94 HTOB getrag and a full rebuilt 92-94 HTOB getrag (15K miles on it) with lots of WOT blasts in 1st, 2nd, 3rd & 4th gears, the occasional burnout and some time on a road course.

Avoid side stepping the clutch and running slicks and use the clutch when you shift and it will last quite a while.


An newer model manual tranny wouldn't be a bad idea either since you can probably get them for less than a rebuilt getrag.

quote Originally posted by Isolde: Does that $550 include shipping? If not, I have a better source, assuming you're in the 48 states. Also, fieroguru has a good thread showing how to attach an F40 to a sBC for far less $ than the kit, and with a far lighter flywheel, plus it fits in the car with more clearance at each end. He shows everything, but for axles I'd just get measurements then call the DriveShaftShop for a set of custom-length Stage 2 Cobalt SS axles, at $800/set. They're rated higher than the F40, and they;re stronger than they're rated, but DSS also offers stage 4 axles if you'd rather frag the trans than the axles. If you expect to break very many F40s, then just start with a cryo'ed NSX 5-speed. There's video evidence out there of these withstanding 1000 rwhp on sticky tires.

6 speed cost quoted is more or less the latest I heard. I got my last one for less than $500. Yes I know you can do it yourself for less money. But if you have the $$ you can have a 6-speed running in one weekend with Archie's almost 100% bolt on kit. That's how I have been enjoying mine for so long much earlier than any self kit out there. But I know not everybody have the $$ and some like the challenge.
Regarding the NSX one I heard it takes more clearance on the driver side. Then I still don't understand how a tranny that came in a car with very low 200s TQ rating can hold so much. Must be the Japs tricks...

quote Originally posted by fieroguru: A properly rebuilt getrag will last quite a long time. I do not know the Hp/Tq levels of your application, but mine was 283whp/317wtq and I put 40K miles on my swap between the Isuzu/highmileage 92-94 HTOB getrag and a full rebuilt 92-94 HTOB getrag (15K miles on it) with lots of WOT blasts in 1st, 2nd, 3rd & 4th gears, the occasional burnout and some time on a road course. Avoid side stepping the clutch and running slicks and use the clutch when you shift and it will last quite a while. An newer model manual tranny wouldn't be a bad idea either since you can probably get them for less than a rebuilt getrag.

Interesting indeed...

As far as the hp/torque figures of my engine... not sure, honestly... we're looking at a freshly rebuilt 350TPI w/ ported upper intake/SLP runners, Vortec heads, mild cam, custom chip, good exhaust and intake system, stock bottom end... nothing too radical but plenty for this little car. I've read that when tuned properly, TPI-based 350's can easily turn 400hp at the crank. Not that I'm expecting this from MY engine though.

Anyways... the later model Getrag's sound like an interesting alternative... which cars did these transmissions come in? Also, when replacing and older Getrag with a newer one, what sorts of modifications will need to be done to make it work?

Thanks again!

Brett

The typical donor is a '92-'94 Beretta 3.1L, and the B-O-P versions of same. These used all the same ratios as the '87-'88 Fiero GT's Getrag. To install it, check out Rodney Dickman's website, he has taken the time to type out all the relevant info, and he offers any parts you may need.

quote Originally posted by ITALGT: ...were these parts letting go at the strip or under "normal" driving conditions? Brett

An axle at the strip, clutches, well all the time.... The axle was more of the drivelines fault, big wheels, low profile tires, and stiff springs make for some interesting things at the dragstrip. Non the less it really beat up the passenger side axle (blew the boot off the tripot), and broke the driver side axle, yet the trans held fine.

The turbo car has been getting beat up on alot and the trans just holds, no questions asked, stock (small) diff.

quote Originally posted by darkhorizon: 00-0? 2.2 (not 2200) cavi/sunfires. The pre 00 years I believe came with an isuzu trans. Shift links will be a pain to swap/setup, but you do get a really nice hydrolic throwout bearing in the process.

Are there any good build threads on this conversion?

quote Originally posted by ITALGT: Aside from laying off the throttle a bit (and avoiding hard launches at the drag strip), what other things can one do to improve a 4 or 5-speed's durability? I know some basic things like a rebuild, running a good synthetic lube, etc will be beneficial... but what else can be done (or has been done) to these transmissions to make them more durable?

The single item of your setup that will have the greatest effect on transmission life is flywheel mass. Keep your flywheel mass absolutely as low as possible.

quote Originally posted by ITALGT: Are there any good build threads on this conversion?

No, a few scattered bits of information. No one step is hard it is just a collection of little tricks and mods, most of which will be different in a v8 application anyway.

Basically, the bellhousing surface of the transmission has to be in the stock location in order for the Fiero axles to work. Beyond that, mounts, linkage, VSS and clutch throw out mechanism all have to be figured out.