It's 280 ftlbs * 3.77 first gear * 3.55 final = 3747 ftlbs, right?
Your math is pretty good. In their original longitudinal application, they use 2 of these mounts, one on each side . The transmission is supported in the center, so that mount does little to resist torque. I figure 4 of the mounts plus a dog bone on top and I should be ok.
Originally posted by Daryl M: Your math is pretty good. In their original longitudinal application, they use 2 of these mounts, one on each side . The transmission is supported in the center, so that mount does little to resist torque. I figure 4 of the mounts plus a dog bone on top and I should be ok.
The longitudinal setup the engine mounts don't experience the final drive torque multiplication due to the 90 degree angle change at the rear end. This means your engine mounts will have to resist 3.55 times the torque loads as the longitudinal setup, so doubling up on the mounts helps, doubles the torque load holding... Granted there is a safety factor built into the mounts, so it they will likely keep the drivetrain in place, but it could move more than you expect.
This is what I always use 4 corner mounts with lower control arm bushings (fully encapsulated and pretty stiff) and space them as far apart as possible.
The longitudinal setup the engine mounts don't experience the final drive torque multiplication due to the 90 degree angle change at the rear end. This means your engine mounts will have to resist 3.55 times the torque loads as the longitudinal setup, so doubling up on the mounts helps, doubles the torque load holding... Granted there is a safety factor built into the mounts, so it they will likely keep the drivetrain in place, but it could move more than you expect.
This is what I always use 4 corner mounts with lower control arm bushings (fully encapsulated and pretty stiff) and space them as far apart as possible.
Very good point. I too placed the mounts as far apart as practical. It will be interesting to see how this experiment works out.
Bumpity Bump.. Daryl, anything new? I recently got myself an F40 trans, still quite some time before I actually focus on my (LS4) build here, I want to see how yours is coming along, that looks like a really good V6 swap alternative to the LS4 F
Bumpity Bump.. Daryl, anything new? I recently got myself an F40 trans, still quite some time before I actually focus on my (LS4) build here, I want to see how yours is coming along, that looks like a really good V6 swap alternative to the LS4 F
Been doing light work due to having shoulder surgery. Also been working on other projects. Rehabing doors that started life as manual window, no power anything. Now will have power windows, mirrors and locks.
With race season over and the racecar packed up in the trailer, back on the fiero. Started disassembling the front end to install a rebuilt/powdercoated setup. Also installing the rest of the SS brake lines.
Finally, just rebuilt the calipers. Car *barely* stopped. That stated, took a spare set of C5 calipers I had in the garage; should be a fairly simple bracket to make. Only question is do I drill out the C5 rotors for the fiero bolt pattern or modify the bearings to fit the c5 rotors.
With race season over and the racecar packed up in the trailer, back on the fiero. Started disassembling the front end to install a rebuilt/powdercoated setup. Also installing the rest of the SS brake lines.
Finally, just rebuilt the calipers. Car *barely* stopped. That stated, took a spare set of C5 calipers I had in the garage; should be a fairly simple bracket to make. Only question is do I drill out the C5 rotors for the fiero bolt pattern or modify the bearings to fit the c5 rotors.
Wiring is where a lot of projects come to die. Keep up the good work though I have been watching this thread and would like to see how well the swap finishes.
Wiring is where a lot of projects come to die. Keep up the good work though I have been watching this thread and would like to see how well the swap finishes.
Me too. If I knew someone that was in my area that would do it for a reasonable price, I'd pay to have it done.
Wiring is where a lot of projects come to die. Keep up the good work though I have been watching this thread and would like to see how well the swap finishes.
My wiring is mostly finished just because I threw money at it.
That said, I went to drop off the front suspension bits at the powder coaters the other week. It was at one company for a week and they couldn't even get around to quoting it. I took it to another shop and they wanted $700 for the front crossmember alone. . .
Either this area is stupid expensive, prices have skyrocketed, or it was a ripoff. I gave them the rest of the pieces and will POR15 the cross member. Hoping to have everything back first week of dec to put that all back together.
My wiring is mostly finished just because I threw money at it.
That said, I went to drop off the front suspension bits at the powder coaters the other week. It was at one company for a week and they couldn't even get around to quoting it. I took it to another shop and they wanted $700 for the front crossmember alone. . .
Either this area is stupid expensive, p TVskyrocketed, or it was a ripoff. I gave them the rest of the pieces and will POR15 the cross member. Hoping to have everything back first week of dec to put that all back together.
I'd be happy to throw a little money at mine, but not sure who to call to do the work.
Guy does great work and is a pleasure to talk to. Tell him I sent you. The only issue I had is they forgot to crimp the strain reliefs on the relay box wires so 1 or 2 came undone. That said, everything else is top notch. They pretty much make the harness plug and play. IIRC, it was $900 and I just had to plug stuff in.
[This message has been edited by RandomTask (edited 11-22-2021).]
Guy does great work and is a pleasure to talk to. Tell him I sent you. The only issue I had is they forgot to crimp the strain reliefs on the relay box wires so 1 or 2 came undone. That said, everything else is top notch. They pretty much make the harness plug and play. IIRC, it was $900 and I just had to plug stuff in.
I was hoping to find a local guy. I have quite a bit of unique stuff to do on the car. Not just a swap. What did you do about the auxiliary vacuum pump for the brakes? How about the fuel pump?
I think the solution I am using is much simpler. The Impala has an electric auxiliary vacuum pump. In the impala, it is controlled by the ECM. I am controling mine with an adjustable vacuum switch. When vacuum drops below a preset level, the pump comes on. There are check valves on the impala that prevent bleed back.
New question for the brain trust. I have noticed that the clutch pedal seems pretty heavy. After some quick research, it seems that the Fiero clutch master cylinder piston is about 36% larger than the Saab that the transmission came from. Does anyone know of an easy fix for this issue? Besides being hard to push, won't the slave overextend?
New question for the brain trust. I have noticed that the clutch pedal seems pretty heavy. After some quick research, it seems that the Fiero clutch master cylinder piston is about 36% larger than the Saab that the transmission came from. Does anyone know of an easy fix for this issue? Besides being hard to push, won't the slave overextend?
Good question, I think you are correct. The clutch pressure plate is going to travel to far. With no benefits to the extra travel and the possibility of pushing the slave cylinder beyond its designed limit, could be a future failure or just a nuisance. I would think about a SAAB master. But this is just a guess. Keep us updated
Good question, I think you are correct. The clutch pressure plate is going to travel to far. With no benefits to the extra travel and the possibility of pushing the slave cylinder beyond its designed limit, could be a future failure or just a nuisance. I would think about a SAAB master. But this is just a guess. Keep us updated
Saab master cylinder would be challenging to adapt due to pedal setup and plumbing. I'm researching for a master cylinder that has a 15mm piston and a more similar mounting system. I also wonder if the Fiero unit can be sleeved to a smaller piston size? I have a couple of the Fiero units sitting around and a lathe. What could go wrong?
Saab master cylinder would be challenging to adapt due to pedal setup and plumbing. I'm researching for a master cylinder that has a 15mm piston and a more similar mounting system. I also wonder if the Fiero unit can be sleeved to a smaller piston size? I have a couple of the Fiero units sitting around and a lathe. What could go wrong?
I get it, and you might be on to something, but is that easier? Swaps are not all plug and play, sometimes some trial and error is required for the good of the group. Keep us updated, thanks
While I would say the 100+ fieros running the F40 and stock master would imply this is a non-issue when properly setup, the easy solution to lower the force and reduce the travel would be to move the banjo attachment up 1/8 to 1/4".
While I would say the 100+ fieros running the F40 and stock master would imply this is a non-issue when properly setup, the easy solution to lower the force and reduce the travel would be to move the banjo attachment up 1/8 to 1/4".
That may do the trick. I'm giving up on modifying the piston size of the stock Fiero unit. As it turns out, using the Saab unit may be easier than I thought. I have one coming and will report back on what I come up with. The difference of the piston diameter is pretty big, 13mm vs. 17mm.
That may do the trick. I'm giving up on modifying the piston size of the stock Fiero unit. As it turns out, using the Saab unit may be easier than I thought. I have one coming and will report back on what I come up with. The difference of the piston diameter is pretty big, 13mm vs. 17mm.
I used an OE new first design clutch master cylinder because it was the most dependable for me of all of them made for the Fiero, and simply spaced it off the mount surface a bit and never had a problem.
I used an OE new first design clutch master cylinder because it was the most dependable for me of all of them made for the Fiero, and simply spaced it off the mount surface a bit and never had a problem.
Do you loose travel in the slave cylinder? I do not have this in my car yet, but one of these days I will put the F40 in and bench the automatic. When that happens, I think the correct cylinders working together should give the best pedal feel and travel for the set up. I believe the original F40 had a dual mass flywheel? And may have required more travel than the Fiero F40 system? My goal is to get my hands on some parts and see first had how it all works together. I really appreciate the documentation and advice. Thanks everyone
I used an OE new first design clutch master cylinder because it was the most dependable for me of all of them made for the Fiero, and simply spaced it off the mount surface a bit and never had a problem.
How heavy was the pedal? My setup with the Fiero master is way more than I want to deal with. Way heavier than the stock 87 GT I sold a couple of months ago.
How heavy was the pedal? My setup with the Fiero master is way more than I want to deal with. Way heavier than the stock 87 GT I sold a couple of months ago.
Loosing travel to deal with the hydraulic volume was the goal, only the pedal didn't feel any different to me. The adjustment was not an extreme amount, possibly 1/4". My initial install used the stock dual mass and clutch. The motor was turbocharged and I noted a slip at some point on what should have been a solid setup. That's when I discovered via email to the flywheel manufacturer that dualmass flywheels (theirs) are torque limited to about 10% above the engine it was rated for.
It was all custom after that, solid flywheel, kevlar disc and modified heavy duty stock GM 2.8L pressure plate to about 2500 lb clamping pressure. The pedal was a bit stiffer, but not what I recall some V8 pedals being. In stop and go traffic in Atlanta it was a workout at times, but I imagine it would have been regardless given the number of times the pedal had to be pressed. The first design master cylinder is a bit more unique compared to the others and it always delivered a firm feel. I always had trouble with the cast iron and steel tube models almost immediately upon putting them in use as remanufactured units.
This is my solution to the clutch master cylinder piston being too big. After considering modifying the stock master cylinder, I decided to go with the Saab unit that matches the F40 clutch. Now I just have to do something with the pedal linkage end.
[This message has been edited by Daryl M (edited 12-18-2021).]
Yes, the Saab master cylinder is in and bled. It feels much lighter. I still have to mount the reservoir and get some hose clamps, but I really like the pedal feel now. Although the wiring prevents a real test, with the pedal depressed, the clutch does seem to completely disengage.
Yes, the Saab master cylinder is in and bled. It feels much lighter. I still have to mount the reservoir and get some hose clamps, but I really like the pedal feel now. Although the wiring prevents a real test, with the pedal depressed, the clutch does seem to completely disengage.
I cut the end from the stock Fiero unit and made a sleeve to splice the old end to the Saab rod. I epoxied it with West Systems Epoxy and their 404 high density filler. The stuff is indestructible.
I cut the end from the stock Fiero unit and made a sleeve to splice the old end to the Saab rod. I epoxied it with West Systems Epoxy and their 404 high density filler. The stuff is indestructible.
Good idea. I made the stock banjo adjustable by cutting it and then welding in some threaded rod and adding a coupling nut.
