12.2@113 on pump gas (no alky)

[murphster]

Just thought I'd post up my time slip on 93 pump gas (no alky). This was on 255/60 BFG Radial TA street tires, not known for hooking. I'm going to try running again on pump gas soon, but this time on my new street tires, 275/60 Nitto 555Rs. This run was on 6/30 of this year.

60ft.........2.005
1/8..........7.919
mph.........90.72
1/4.........12.241
mph........113.59

With alky and a little more boost, I was able to get some 1.9 60fts out of the BFG TAs. The Nitto 555Rs are pretty decent street tires and last for a decent amount of mileage. They aren't near as good as something like the Mickey Thompson DRs, but I actually got some decent 60fts on them (I got a lot of 1.7s and even a 1.6 60ft) on my alky tune. Now that I've got my pump gas tune at 20lbs of boost in the good weather, I'm hoping to get something like a 11.7@117mph on the Nittos on pump gas (no alky).

As far as tuning on pump gas, I'm using the same TT alky chip. I took out all of the first gear fuel through the chip and maxed out the WOT fuel (on a dual nozzle alky tune I normally leave the WOT fuel correction near 0 so I essentially added 20% WOT fuel for pump gas only). My car doesn't like high timing at all, even with alky or some race gas thrown in. I pulled out timing so that I'm running 18 degrees in 1/2 and 17 degrees in 3rd gear. I normally run 21/19 timing on alky. Anymore than this and I start to see some knock up top. I've run a best of 11.0@121mph on pump gas and alky at 24lbs boost.

Here is the combo:

.30 over 109
Champion heads and matched intake.
206/206 roller Comp cam and roller lifters.
CPT61 BB turbo
rjc boost controller
3" THDP
Big Mouth cold air kit, 3" MAF with MAF translator
CAS V4 stretched stock location intercooler
RJC power plate
63lb injectors
Walbro 340 "hotwired" fuel pump
TA ceramic coated headers
ATR dual 3" exhaust
TH400 with manual valve body, hipster tbrake, TCI streetfighter converter
B&M Quicksilver shifter
EGT gauge and Directscan for tuning
Savitske springs front and rear, Bilstein shocks all around
Boxed stock lower control arms, stock uppers
Energy Suspension bushings in upper and lower control arms
Stock 8.5" rear with 30 spline Eaton posi and Moser axles
HRparts rear swaybar, no front swaybar
Centerline Convo Pro wheels, 15x7 up front, 15x8.5 out back
Bob Bailey 2step (didn't have this yet on the timeslip above though)
.
I'm sure there is some stuff I forgot to mention.
.
.

 

[WINDMILL]

work on the suspension some and you can get the 60fts down... i've been high 1.6's on reg radials, constant 1.7's all the tme..

 

[murphster]

Which radials? I think the brand and size make the difference. On something like 275/60s on a decent brand I don't think 1.7s would be an issue. I think the 1.9s on the 255/60 BFG TAs was pretty good since the tire is crap as far as traction and that size tire isn't the biggest footprint.

 

[WINDMILL]

best i've ever had was a 1.62.. the tires are multi-mile tires grand am tire 275x60 tire size.. this time i used a 10 inch wheel seems better.. i broke my 9 inch ford rear end last time out,, hope to have it back going for the turbobuick nats if i dont sell it.. i'm hopeing for some 1.5's 60fts and 6.8's ets next year on them tires..

 

[sweetv6]

good work !

pretty nice car too

i like that color

claude

 

[pacecarta]

well you came close murph

hopefully youll have better luck next time , i know it was wed the 17th and not fri 13th but i think you broke a mirror and drove over a black cat on the way there

all in all 12.0s isnt bad either

 

[murphster]

I'll post up the whole story later, cause I have to go. But a quick summary is that I overheated, had the throttle get stuck open, and flatspotted a front tire, all in the same 1/4 mile pass! Drove it home though.... thanks Paul!

 

[pacecarta]

heres the results from todays day at he track , the grip was terrible

congrats Scott on the 11 sec run on pump gas and nittos

 

[murphster]

Thanks Paul. Weather was too cold for good 60fts on the Nittos, but I still got the 11sec slip, which was my goal. I was limited with my tune in the cold weather because I had already added all the fuel I could through the chip. I had to turn the boost down to 18psi, but based on the mph I was making the same if not a little more power than the 19psi I ran in June.

I made three passes in all. I spun bad on the first one. On the last pass I added some air to the front tires and hit it a little harder. The track was cold so I didn't want to risk spinning. I've gotten consistent 1.7 60fts on the Nittos, but that was in decent weather and a sticky track. here are the three passes:

60ft.........2.036
1/8..........7.910
mph.........90.67
1/4.........12.231
mph........114.50 <--- best mph on pump gas

60ft.........1.850
1/8..........7.738
mph.........90.42
1/4.........12.082
mph........113.64

60ft.........1.806
1/8..........7.649
mph.........91.24 <--- best 1/8 mph on pump gas
1/4.........11.966 <--- best ET on pump gas
mph........114.27

So, all in all a good day. With that mph and sticky tires like MT drag radials or slicks, 11.5s should be possible. That might have to wait until next year though.

As far as last week, my dual fan harness stopped working right before my first run and I didn't notice it after the run. I hotlapped the car and make a second pass with the temps in the lower 200's. I always watch the temps when I first start the car, but I guess I didn't keep a good eye on it once I saw the temps were holding stready. On the second pass, the throttle hung at about half throttle at the top end of the track after I let off. A pretty exciting experience. After trying to unjam the peddle, I shut the car off. I also keept my foot on the brakes hard as I was worried about running out of track. Turns out I ended up locking up the driver's side front tire. I came to a stop and noticed smoke behind me. I also had a little water coming out of the overflow. Didn't make sense to me at the time why it was running hot because of the stuck throttle. Turns out I just got lucky and had two problems at once. The front passenger tire may have been sliding in water so all the the stopping power was on the front driver's side tire, who knows. The throttle stopped sticking, put some water in it and drove it to Paul's with the front tire going bump bump from the flat spot. Bought a new throttle cable and checked out the throttle body, etc. The only thing we found was a broken spring on the pedal side of the throttle cable that could have gotten stuck.

Its pretty cool that the car is an 11 sec ride without alky on my current street tires (Nittos). Not too long ago I was just happy to have an 11 sec ride going all out with race gas, sticky tires, etc.

 

[murphster]

Doing some upgrades to the car. Will make the car faster, no doubt, but it will be interesting to see if I can gain anything on pump gas.

Here are the planned upgrades:

CPT61 BB ---> CPT66 BB
CAS V4 IC ---> Cottons FMIC
stock TB/plenum ---> 70mm TB/plenum
3" THDP with internal wastegate ---> 3" Cottons DP with external wastegate

At the lower boost I was getting boost creep and the wastegate hole is already as large as can be. With the bigger turb going external is probably the way to go. Plus I can easily go to an electronic boost controller.

I also noticed that my TB and plenum don't match well. They appear to be stock though. The obstruction in the airway path cannot help.

Going to a Cottons FMIC from the CAS V4 will result in better cooling and less pressure drop (maybe 2 psi). Might help make more on pump gas with cooler temps.

Looking at the compressor maps for the turbonetic turbos, on my race tune the 61 was starting to get out of the optimal area of the map. Going to a 66 will leave plenty of room. On pump gas, the 66 will also be in a better area of the map but the difference probably won't be as significant as when I turn up the boost on alky.

I'll post up the results in the spring.