Mid- Engine Modified Sports

[Milwaukee Midget]

I saw and heard the run - and THAT was a thrill!. When Neil went to what I thought was 3rd gear, the revs dropped off the table. Turns out he dropped it into 5th, but my first thought was, "Whoa Nellie, that's a wide-ratio box!"
I think "Red Hat" Ross and Neil were the happiest campers on the salt this weekend.
Congratulationa, Neil!

[4-barrel Mike]

Excellent! 

Mike

[Interested Observer]

Neil,
Congratulations, looks like you had a really nice first run on the salt.

Extrapolating from your 5633rpm/150 mph calculation to 157.5 mph would give 5914 rpm or, a 23% error.  This couldn?t be accounted for by tire growth alone. Time to count engine turns vs. wheel turns to verify 5th gear ratio.  Also, is the tach calibrated?  Or, maybe you have invented negative wheel slip!

The car felt stable but wandered a bit at high speed

Some things come to mind on this. As you mention, front toe setting, but also..
Rear toe?  Front and rear bump steer?  What is F/R weight distribution and has the CG/CP issue been satisfactorily evaluated?

[Koncretekid]

Congrats on your successful run. I wandered around your car as we too waited out the wind delay, but never saw anyone around the car.  Disappointed that I didn't get to meet you.

Tom

[jacksoni]

 IO your post was somewhat confusing that suggested 150 to 157 took 23% difference. Actually you were calculating from Neil's posted 4800 to get the 157 number which would be as you suggest and not within tire growth area. 150 to 157 is ~5% and within tire growth area. As you suggest there is a gear/tire miscalculation somewhere.

[Stainless1]

Congratulations Neil... nice first pass....
All cars wander a little on the salt... the trick is to let them wander a little, not fight them too much...
Lots of chassis things you could check... any bump steer, front or rear is bad... I don't remember seeing if you had it on scales to check wheel weights...
My calculator is generally accurate... post up what you think you have and we can run the numbers... to get a good diameter don't trust posted size... run a circumference tape... doesn't take much to pick up some speed...
It's been a long journey to here, now the real  fun begins... it's harvest time....   

[Seldom Seen Slim]

About the car hunting some:  Sounds like what I describe as "I had to do a lot of steering to go straight".  So much fun!

And now comes the chain-yanking:  From what I heard in the video, you might have attended the "Al Teague/Carl Heap School of Gear Shifting" - although you did explain later on...

But dang, that must have been fun.  I enjoyed just watching.  Thanks and best wishes for next time, too.

[manta22]

Thanks for the kind words, guys. I still have a smile on my face this morning. I'll unload my truck and roll the car off the trailer later today. We drove straight home to Tucson on Sunday and I was too tired to tackle that yesterday.

My F & R suspension geometry is very good, with very little bump steer but I have not adjusted its weight balance yet. The feeling in the car at speed was like driving on the freeway in a moderate crosswind- not alarming but I could feel the car move a bit and I gave the steering very little correction. I'd like to run it on asphalt to see if it feels the same or if it is something peculiar to driving on salt.

The first thing I'll do to check my speed vs RPM spreadsheet calculation is to double-check the equation and then check the data inputs. If those look OK, I'll measure tire circumference and actual gear ratios. I did calibrate my tach with a function generator and frequency counter- it is accurate. I short-shifted to 5th because the engine had more than enough power to get up to 150.

Next year can't come soon enough!

[JimL]

Neil, many years ago, I visited Dennis Aase (and his brother) to talk about his Toyota MR2 record of over 200 mph.

He said that running a short wheelbase, rear engine car was "just like putting the front bumper against a telephone pole, and then trying to stay behind the pole at full throttle...in high gear...on ice."

He did show me a lot of ballast in the front end, added after his first trial runs.

It was good to see your first runs were successful.  These salt flats projects are the longest of our lives, and most folks don't understand.

[manta22]

Jim, I added the tail fins and the largest legal rear spoiler that I could so I think I had some significant downforce working to keep me going in a straight line.

We returned home from Bonneville, cleaned up the car a bit and yesterday took it to a small local car show. Now we are back home; time to unload it once more from my trailer and roll it into the shop.
 

[manta22]

The Pot-O'-Gold at the end of the rainbow.......
 

[Stainless1]

Neil, I think that might be the reverse.... it's the self-emptying pot you've filled with gold and need to keep doing so to feed your addiction.... 
Nice pic 

[Stan Back]

Somebody fill me in -- I'm not authorized to have a Rule Book any more.  The SCTA website doesn't have the records (at least where I can access them).  So, what the current B/GMS record?

[manta22]

Neil, I think that might be the reverse.... it's the self-emptying pot you've filled with gold and need to keep doing so to feed your addiction.... 
Nice pic 

It's the pot I've been pouring my gold into for years, Bob.

[Elmo Rodge]

252.955 Stan.