GT750 Powered Race Car (D-Sports Racer)

[rodneya]

Check Packard Racing for throttle cables.

[sav0r]

Our cables are pretty specialized considering they run from a throttle pedal at the front a car back to a mid engine motor in a chassis that was built by my father 50 years ago. I appreciate the response though.

[rodneya]

Lectrons need cables with lectron threaded ends to go into the carb tops, so you need at least the piece from the carb to the splitter.
Probably worth a call.

[sav0r]

Inside the plastic organizer that had the book on top are a bunch of parts for connecting them up. The slides appear to use a standard barrel type termination, but I could be very wrong.

[sav0r]

So there is a good bit of hope for some racing this year. Covid cases are in freefall and vaccinations are climbing rapidly, that includes my father, he's 72.

This in mind, my father is feeling much more optimistic for 2021. We spent a few hours working on the car yesterday, mostly playing with driver ergonomics. They weren't quite right and it meant that a variety of issues existed with my fitment in the seat. Mostly my head angle incorrectly accommodated my HANS device. That said, we also worked on the motor, it's almost back together but I managed to grab these photos.

[teazer]

That aluminum timing gear looks dead sexy Chris.  Back in the day Wassell in the UK used to sell aluminum three keyway timing gears for Triumph twins.  They did wear faster than stock steel gears but not by much and they don't crack like plastic Suzuki gears used to.

[sav0r]

I looked into doing them out of 7075 as well as brass and even steel.

I might just anodize the next round of them. Since I don't spend a lot of time minimizing tooling marks around the center of the gear it probably won't look amazing, but the teeth come out great and it would add a lot of resilience to the wear surfaces.

As you well know, the stock gears are pretty marginal. When busting the gears off the hub they come apart so easy that it's amazing they ever worked. There clearly isn't much load on them.

[sav0r]

I forgot to post this. Our BDK magnesium water pump cover apparently wasn't cast too well. It has pinholes all over, but also one giant hole that seemingly formed. I am going to do some backwards engineering and just machine one out of 6061. It won't be as elegant as the cast version, but it will work, and it probably won't develop holes in a year. I might do an impeller while I'm at it.

[sav0r]

I did a test run with some machinable wax. Figured I could fit it up before actually making one out of aluminum. This took quite a bit of reverse engineering and I can tell right off the bat there's a few things that need some work on the model side, but it seems like it's a good start.

[teazer]

That's a nice piece, but can't you just use a stock GT750 cover?  I have a brand spanking new (NOS) one here looking for a new home.  Yours in exchange for a small pile of drink vouchers.

[sav0r]

The housing is actually deeper as to accommodate the taller impeller.

Replicating (well not the back side for now) this but hopefully without the porosity - https://bdkraceeng.co.uk/tc/products.php?281&cPath=6_68_79

[sav0r]

Semi long day of taking care of my wife who has pneumonia and machining stuff when I could.





The wax one fit perfectly. We sectioned it on the band saw so we could see the fit to the impeller. It appeared to be spot on. So I went for it in aluminum. We test fit tomorrow. Plenty of time for a version 2, but I really hope it doesn't come o that.

We are on track for our first test this year in 6 days.

[sav0r]

Things are looking good! Coolant is in check. No major leaks (lol), a bit of a drip at the transmission, it will be fine. Brakes are bled, totally new brake setup for us (modern stuff thankfully), I think it will stop. The clutch seems marginal still. Not a big deal for a race car assuming I don't spin or otherwise stop. Seating position is tough, but I will deal.

Everything is set for a Friday test at Pitt Race. I can't wait to run Pitt Race in anger again, I literally lived at the track for a summer in 2010 when I worked in exchanged for free track time as I launched my short lived professional driving career. I have raced at least one race a year until 2020, it broke my 25 year streak. At my best, I raced 35 some races a year, so 2020 was quite painful. I can't wait to turn some laps in anger. I'm sure my Sportwagen will enjoy the relief.

I also get my first vaccination tomorrow (please avoid political commentary), I feel extremely pleased with this. I am feeling very optimistic for 2021.

[85RZwade]

We're out here cheering for ya Chris 

[sav0r]

Thank you!

We just push for fun. My father loves the challenge (me too), and the hard work keeps me out of trouble. There is nothing to be won or gained asides from personal satisfaction.

The Pittsburgh Vintage Grand Prix track is rather unique. Something akin to a proper road racing circuit that have mostly gone away. It's very dangerous, but insanely satisfying to race. I hope we can realize our goal of resetting the all time lap record. I kind of doubt it will happen this year. Next year seems very possible. Development cycles are very tough. We are reasonably versed, but only have so much time and money. Such is life.