Drag Race Results 8-18-2017

This was the first time out for the season.   The new Ron Lummus' Black-Magic Clutch Disc is awesome!  (I look forward to when I can upgrade to the Rev-6, but for now I am using an old school Kennedy 2300 "green" pressure plate.)

I was given 2 time trial runs on Friday and the 60 foot times were 1.375 & 1.372 launching at 5,000 rpms. My data logger is full from last year and I am having trouble erasing it so I can record more so have no data from those two runs to see what is going on, but after first gear, it just doesn't seem to be pulling as hard as I think that it should. Any case, it ran 10.15 and 10.19 at just under 130mph.

Here is an in car video of the first run…


…and here is a video of my third time trial run…


I had a great time at the track this weekend. Once I get the car to boost properly on the track it will fly. With only 10 psi of boost it was still running fairly well.... 10.15, 10.19, 10.17 & 10.15 in time trials.  Due to a boost issue that I am fixing, it bogged during the first round of eliminations so only ran a 10.33. (I will have it fixed before next weekend.)

Also since I have not raced in soooo long, I am happy with the lights that I cut. With a little more seat time (now that it is turbo) and dialing the car in, I should be able to go rounds. My reaction times for the time trials were.... .027, -.030, .097, .037 and then first round of eliminations I cut a .005. (Not too bad for an old Ninja!)

I will be back on the dyno this week and then hopefully I will get it back on the track a couple of more times before the end of the season

Information on the boosting issue…

After my first two time trials on Friday, I suspected it was low on boost and since my data logger was full and I couldn't clear it (another issue I have to resolve ASAP!) I installed a boost gauge in the car Saturday morning before the next day of racing. After reviewing the in car videos (Which I will post later today) on both of my time trial runs it made about 17/18 pounds of boost while on the two step. As soon as I launched each time it dropped to 10psi while still in first gear and stayed pegged at 10psi during the entire run. (Although I was disappointed that the car did not run a 9, I am pretty stoked that it ran low 10's at only 10psi. I am excited to see what it will do at 20 psi and then eventually 30 psi!)

Any case, during the first round of eliminations, I dialed a 10.15 and I had to race a little pickup that dialed a 12.46. As soon as we were both fully staged, I put my car on the rev limiter as I did each of the four time trial runs. However, since I was on the two step over two seconds longer, you can clearly see in the video that the car reaches 17/18 psi and then drops to 10 psi just as I release the clutch. With the lower boost, the car lays over a bit at the hit and instead of high 1.3's or even low 1.4's it produced a 1.524 sixty foot time.

So, needless to say (but I will anyway!) once I sort out the low boost issue, this car if going to be very fun! Trust me, even though the car has not performed as well as it did on nitrous yet, I do not regret for a second that I made the swap to turbo. The potential is apparent and I truly believe that I will have a VERY consistent 9 second bracket car capable of running high 8's when I turn the wick up.

If you watch the tach in this above video I posted on YouTube (of my first time trial run) you will notice that at launch, it jumps from 5,000 rpms upwards pretty quickly and carries the front fairly well. However, you will see that in the elimination run where I chase down the pickup...


...the tach drops from 5,000 to about 4,000 at the hit. I am 99% sure based on looking at everything that it was due to being on the rev limiter longer and the back pressure in the exhaust having time to force the waste gates open.

When I first set the car up I went with 6 psi springs (Small red with the 38mm Tials) and I plumbed it where the intake manifold boost would assist the springs to help hold the WGs closed. Then I had it wired and programmed to dump that pressure and add pressure on the opposite side of the diaphragms. The intention was to have more control and the ability to run as low as 6 psi, if I wanted too. (Got the idea from the third page in this article... http://blog.perrinperformance.com/boost-control-systems-explained/)

Any case, it didn't work as planned, probably due to my inexperience with tuning PIDs, so I reverted back to having the spring side vented all of the time and only controlling from the one side. This gave me adequate control, but I didn't think about the fact that most likely with the small low pressure 6 psi springs, it is probably building enough back pressure to force them open at about 10 psi intake pressure. Or at least that is what I am theorizing at this point. I have a pair of 14 psi springs (Large blue) ordered and will do some re-tuning on the dyno.

This should give the ability to actually hold boost longer on the starting line, build boost down the track and also to make more than 18psi on the dyno. On all of the prior dyno pulls, it was never able to make 20 psi or higher boost and I thought it was another issue, but I am thinking that the small springs were pushed open during the pulls rather than the boost controller doing it. The only reason I think that I was able hit 18 psi during my 3rd gear pulls was the time it took vs. the time on the actual track run.

Soon I will do a 3rd gear pull, 4th gear pull and simulated 1/4 mile on the dyno to see what it does before changing the WG springs and see if I can prove my theory before going back to the track Saturday the 26th.

I am sooooooo stoked to take it out Saturday as I think it will actually boost and I can’t wait to see what times it will run!!!