F40 upgrade worth the price?

[microsoftisevil]

Deciding what to do with your Goblin is definitely a personal choice and weighing the cost of new and upgraded parts against using parts from a donor is not easy. I spent a lot of time researching engines, transmissions, brakes, and suspension before deciding what to purchase and what to reuse. Part of my choice was made by the availability (or lack of availability) of replacement parts that don't have 131,000 miles on them from my donor. In the end I will be spending more money than many other builds strictly using donor parts, but they are new versus used and will provide me with the confidence to not fail at sometime in the near future. It's all good!

You’ve been super helpful, but I’ve got just one more question about the F40 swap. Mechanically everything can be adapted and changed over... what about any electronics? Does the computer care that there’s an extra gear in there? Speedo? Thanks!

 

[Desert Sasqwatch]

The one big change is to have the ECM reprogrammed for an F40 6 speed conversion. The ECM is programmed from GM for a 5 speed and I am not sure how it will respond if you add a 6th gear without reprogramming. ZZ Performance has a canned program for the ECM with a 6 speed conversion, this is the one I will be getting purchased pretty soon. There are many options with this program and I will also be adding the GM stage 1 MAP sensors to my reprogram. The program and sensors run about $265.

 

[Desert Sasqwatch]

Awesome, thanks for the info. Guess I better get my stuff in order. I’m still mid-June for my kit. Hoping to start tearing into my donor here in 3 or 4 weeks. I have been spending my weekends and free nights helping my buddy finish his shop where I plan on doing the build. Always rent to be paid, even if it’s in sweat equity!

Did you get your kit ordered with the F40 option? Just following up in case you had any further questions or discussion needed on the subject. I made the decision to go with the F40 after looking at the outrageous cost of the rebuilt F35 with LSD. I did not want a used (and abused) F35 in my car with a new engine and clutch since this did not make sense for me. When I was seeing F35 rebuilds going for $2400 and up, that was the decision point for me to go with the F40 and order up the LSD from Quaife. The cost between the 2 was a wash, but the F40 was 0 miles, has better gearing toward the top end (3rd thru 6th) to match the power of the (relatively) stock LNF engine, and has about 15% more toque capability. Since I will be getting my kit in about another month or so, I will be adding more to my build log and will be showing the process of installing the LSD in the F40. BTW, ken Leiker is also in the process of finishing his car with the F40 and is another source of information if you need it.

 

[microsoftisevil]

Yep, I pulled the trigger on the upgrade. Kit is about ready for pick up (need to call tomorrow). It’s a steep up-front cost, but next year I plan on dropping in a ZZP racing block and getting her into the ridiculous power to weight ratio range. Not feeling like paying for F35 rebuilds when it grenades.

Still need to get a LSD on order. May hit you up soon on that unless you have a part number handy. Also, I'm assuming this upgrade needs different axles. Of course, ZZP is out of stock at the moment!

 

[Desert Sasqwatch]

Yep, I pulled the trigger on the upgrade. Kit is about ready for pick up (need to call tomorrow). It’s a steep up-front cost, but next year I plan on dropping in a ZZP racing block and getting her into the ridiculous power to weight ratio range. Not feeling like paying for F35 rebuilds when it grenades.

Still need to get a LSD on order. May hit you up soon on that unless you have a part number handy. Also, I'm assuming this upgrade needs different axles. Of course, ZZP is out of stock at the moment!

This the LSD I purchased (see pic) after much discussion with WG Motorparts in England - on eBay - about getting the correct one for the Buick Regal GS F40 version. I put some info about my purchase experience in my build log.

 

[Desert Sasqwatch]

The LNF turbo axles fit the output splines of the Regal F40, so no problems there.

 

[microsoftisevil]

This the LSD I purchased (see pic) after much discussion with WG Motorparts in England - on eBay - about getting the correct one for the Buick Regal GS F40 version. I put some info about my purchase experience in my build log.

You’re awesome! Thanks for helping me make the right decision.

I’m picking up the whole kit instead of stages, so I have been dragging my feet on getting the transmission stuff ordered haha