F40 6spd conversion research

[woody90gtz]

Well, I did break a 282 drag racing, so the extra beef with the F40 is enticing. I spent a lot of money on axles, diff & clutch to make it all reliable, and the damn 282 itself went. You can also get an F40 brand new, and not well-worn 100k+ or even rebuilt like a Getrag. 500rpm lower cruise at 75 and the idea of the first 6spd Beretta are also some reasons I'm considering. I did put a T56 6spd in my Camaro and LOVE IT.

Nate, these custom swap parts you're talking about sound sweet. Any idea on price and timeline? Ideally an alum flywheel made for an F40 would be better than a spacer, but I've got a lot of irons in the fire and need to keep the budget for this project on the low side.

[3400-95-Modified]

You had this trans apart though and did a rebuild kit on it, are you POSITIVE it just isn't a result of that? Simply something went wrong? Hell I've done it before. I've heard of WAY more powerful cars than yours running just fine on a 282... Rodney comes to mind actually.

[NateD4]

The problem I've seen with 282s are the mounts breaking. Once you fix that the case breaks.

BTW are you running a spring hub clutch?

As to the flywheels... I'm aiming for around $450. Certainly the ones I've seen are worth $500. But when you add steel wear surfaces the price tends to go up.

What kind of engine specs are we talking?

[3400-95-Modified]

He has a completely stock 3400 at the moment with only headers... So unless he is planning on changing that I think any transmission upgrade is a waste of money.

I really think you need to determine the point of failure before you can necessitate any type of upgrade need.

[woody90gtz]

Jon, I split the trans to install the LSD and replace the bearings and seals that were easy to get to. I did not disassemble the trans any further than that. My guess is that a 180k+ shift fork just broke due to wear & tear. I put some hard miles on it for sure, and who knows what it was subjected to for the majority of its life. I do need to get it out and take a look.

As I stated, one of the main reasons to swap to an F40 would be a BRAND NEW 0 miles unit. Brand new vs. brand new the F40 may not be that much stronger, but brand new vs. beat on I bet there is a substantial difference. Any time I break something I would certainly prefer to upgrade rather than simply replace. Whether that is in the budget in this case remains to be seen.

Yes, sprung hub SPEC Stage 2+ and stock 3.1L flywheel.

[Joseph Upson]

As I stated, one of the main reasons to swap to an F40 would be a BRAND NEW 0 miles unit. Brand new vs. brand new the F40 may not be that much stronger, but brand new vs. beat on I bet there is a substantial difference.

There are some later model 282s available that can be had used that would likely still be a better option. For what an F40 swap will cost you, you can probably buy a 282 brand new and have change left over. The 6th gear may not net you any additional fuel economy if your engine torque can't sustain that gear at cruise without significant throttle input. Did I mention first gear is terrible and second too much to take off from a stop in. On a power take off first gear is gone so fast it makes for a frustrating shift, not to mention the 06 trannies are temperamental and prompted some changes in the 07 model. Every once in a while first gear kind of disappears briefly and sometimes you're not in first eventhough you are in first. Yes you read it correctly.

[woody90gtz]

So in your eyes the F40 would be a last resort? And how do I tell if these 0mi trans I'm seeing are 06 or 07+?

I took a look at the gear splits and they aren't far off a v6/3.61 282 like mine.

At 2000rpm with the 282 you're at:
12/20/30/44/57mph in the 6spd at:
11/20/32/44/55/67mph.

At 75 in 5th on a 282 is 2624rpm where 6th in the F40 would be 2221rpm...which is still more than the 2113rpm of a stock 4T60E Beretta. I think 6th gear would have a substantial impact on highway fuel economy. I got 32mpg with the 5spd setup, so it's not like I'm hurting for mileage but more is always better.

[robert 1980]

Well good luck either way man.I'll just be happy when it's running so we can race.lol
J/k

[Joseph Upson]

So in your eyes the F40 would be a last resort? And how do I tell if these 0mi trans I'm seeing are 06 or 07+?

In my experience, which is everyday I drive my car. You'll need to check the P/N. The 07 model looses the .6x overdrive. If you don't need the F40 I'd advise against it having done the swap with a need for it.

[3400-95-Modified]

We can speculate all we want I guess, but until you get it apart you have no idea what let go... I also think if mileage had worn a fork to the brink of failure you might have noticed that when you had the case split, but that's just me.

The way I look at it is shit happens, Hell I didn't want to admit that I put a clip in the wrong spot but once I had my trans apart again it was obvious what I had done wrong, and that was one of the simplest parts of the assy when it comes to that trans. That's why I wonder if it could be from having it apart. I'm not trying to disrespect your work but it happens to all of us.

[Joseph Upson]

My F40 is failing. After a couple of 11 psi runs yesterday my odometer stopped working and I heard a faint whining sound immediately after both runs that went away after llight driving.

I removed my VSS sensor after confirming power to my odometer and Dakota signal converter and noted it had "metal hair" on it along with a chip in the plastic casing down to the coil winding which had been damaged knocking out the signal.

Not sure if it's failing because my 4.2L and base 3900 under boost produced more power than it could handle, or if it was already injured from the wrecked car it was salvaged from. Not sure of the initial miles but I've put about 10k on it.

[woody90gtz]

Thanks for the update Joseph. That is less than encouraging though...although I know I'm making way less power than a boosted 3900.

[TGP37]

I am putting a 282 behind a boosted 3100 expecting 380-400 hp at first. PontiacJeff, the guy behind the EP LSD personally built my getrag-282 and put it an LSD as well. With a clutch capable of 500hp, the trans is expected to hold out pretty well.

I bet you are a victim of unfortunate circumstances. Sometimes good things break in their comfort zone.

[Joseph Upson]

I am putting a 282 behind a boosted 3100 expecting 380-400 hp at first. PontiacJeff, the guy behind the EP LSD personally built my getrag-282 and put it an LSD as well. With a clutch capable of 500hp, the trans is expected to hold out pretty well.

I bet you are a victim of unfortunate circumstances. Sometimes good things break in their comfort zone.

I think it's the result of the first year application in a GM car. I'm not sure if the Saab owners were having the same problem and considering the tranny has been around since about 2003 or 4 I believe GM may have tampered with it resulting in the problems found in the 06 release that were corrected in 07.

It is possible that I contributed to the problem by using synchromesh instead of the F40 specific fluid which is synthetic and a unique more viscous grade than synchromesh although it wouldn't explain away the problems with the trannies that have the correct fluid in them.

It's also possible a piece of something from the internal shift linkage broke off because during the difficult moments attempting to shift into first I can tell something inside the transmission is flexing allowing the external shift linkage to move forward without first gear being fully engaged until I come off the clutch a little and feel it snap into place.

Whatever the case, I have a new tranny waiting to be installed and so far the current unit is still handling business managing an occasional 10 psi. The motor is really pulling hard especially in 3rd gear in 30 deg ambient temps and that's without an intercooler resulting in inlet temps of about 110 deg at 7 psi.

The new tranny will have a fully sprung clutch hub to help reduce the impact of the
4.2L which I also plan to reinstall hopefully at the end of the month.

[Joseph Upson]

Take a look inside the F40 and note the nylon caps at the ends of the shift forks, perhaps one of those came off and came around on the final drive and took out my VSS;

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