Real world results of my $1100 of mods.

No excuses, no B.S., no armchair warrior arguments. Video Proof.

This results were including the fact I had deleted the performance ECU tune (approx 18 rwhp), which will be re-installed and I will run again even faster.

This was on street tires, wheel spin was a problem, there was a decent headwind, but I am making no excuses, when I run a faster time, I'll post the faster time. These are the actual results I got from a real world performance. The same track was used for my before and after runs.

My time improved .606 seconds ! From best of 13.839 @ 101.43 to 13.233 @ 105.34 I ran 3 runs all within 1/10th of a second of each other.

I have attached a pic of the time slip.
I'm providing the video because time slips and dyno slips can lie about what car was used or what "corrections" were made. There are no corrections to this time, no massaging the results. This is what really happened.....on video. This effectively answers the question about the real world results from my mods, no if's and's or butts! I am hoping with the ECU tune and a little luck I will break into the 12.90s on street tires.

 

What tires are you running? I know my STR is a bear to launch so I can only imagine how hard it is to get a xjr to hook up. I am trying to get a second set of wheels with some DRs to be able to launch somewhat better.

 

Hancook Ventus 255 40 18

The one legger rear end seriously limits the launching capability.

I rolled into the throttle and let the traction control do it's thing until just after shifting into 2nd gear, when I turned it off. If you look at my launch on the video, I think I was able to maximize acceleration this way within the limitation of one drive wheel on a street tire.

With the tune, I'll try to get the rev limiter raised 500 rpm, which might allow me to cross the finish in 3rd gear rather than just having shifted to 4rth gear.

I'm thinking with just the $600 Tune, I might be able to break into the 12s with the car set up as it is, even on these street tires.

 

Whoa only 255s? Time to get wider rims as well!

 

This car is a total sleeper, so I'll keep the stock tamer looking wheels. I even have an XJ8 badge on the back. When I put the hammer down, it takes a while for the guy in the BMW in my rear view to figure out what just happened

 

You could always try to go with the STR wheels to run 275s

 

Very interesting if they can raise the rev limiter. I know the problem when my end speed was 105.4-106.4mph last summer. Shift to the 4th gear comes just before finish line. That's not good.

 

Don't get too hooked on a tune, unless you can get a custom one!

With the new Pro-M MAF you will already experience a slightly leaner mixture than stock which is part of the MAF tune. Perfect setting imho, slightly richer than 12.5, so you are on the safe side. So secretly you alreay have a tune ;-)

I would only add (if you are not upping the boost further) 1.5 degrees ignition advance, will not bring that much but a little again, so might be on the expensive side for what it can bring.

 

My dyno showed I actually ran an AFR of 11.3 to 10.9:1 between 4600-6000 rpm, if I can get it closer to 12.5 or so I think I will see a little more power gain.

 

If the time is your goal, then you need to loose weight as well, get rid of the spare tire, tank almost empty, lighter wheels/tires (though that could be more expensive).

 

I could do that, but I want to know what my car really does in full street trim.

I ran the tank this time at 1/4 full, where the baseline 13.8 was with 3/8 of a tank. Close enough for me, since I want to know what my car will do on the street.

If I was only concerned with times, I would not be using a 4000lb car with 4 comfortable leather seats, a/c, and a nice stereo

 

Didn't suggest to drive another car or throw out your stereo.

You always said you wanted a fast time with your car, so my suggestions are stil streetable, using your own car, even the spare tire removed, some use special tire fillers (which I wouldn't use though).

The lighter tire/wheel combo might be expensive, but still normal streetable, I was amazed about the differences there are in tire weights, and also the wheels itself, so not sure why you ignore that.

Here is a fun article:
SCC Technical Assistance Program

 

Yeah, I'm changing my mind of what I want this car to be for me. A 12 second, low cost, easily smogable, comfortable, sleeper, 4 door saloon is good enough for me.

I'm looking more seriously at a Lotus Elise with 310 RWHP at 1700 lbs as a fast toy car. I'm also thinking that any more money I would put into this car beyond getting me to the 12.9x 1/4 mile time is money that could be spent on acquiring the Lotus.

Or...spend more time with the Big Beast 1973 Pantera...