Grip Grip

My first time racing the CL65 was a few weeks ago, and it ran a best of 11.50 @ 120 with a 531' DA with a 1,100 RPM launch.

Yesterday, with the addition of a TCU/ECU tune, but with a 1,758' DA, the CL ran three 11.3's @ 120/121. I was launching it a 2K RPM's, which likely accounted for 1 tenth of the ET.

FWIW, I was running torco and the AIT's never went over 140F. Shouldn't I be picking up more than 23/24 MPH on the back-half? I was picking up 25 MPH stock.

Dr Matt

Since I don't have enough track time with my CL to say for sure how much the DA effects the car I can't say for sure, but after only two weekends at the track I believe these things are very sensitive to air quality. I would expect you to pick up at least 2-3 mph and you got 1.5 which is close so given the higher DA you might be OK. I would not get too worried about it if the car is running well until you get a chance to run in some better air and see what the car does then.

Grip Grip

FWIW, if I use the most liberal DA Correction on Dragtimes it corrects the 11.30 @ 121 to 11.07 @ 123.5 MPH. A 11.0 I could live with, I just need some really, really good air to have a chance of making it happen.

Dr Matt

And that is about where I ran on 90 octane with Torco in a 400' DA.

I also had K&N filters, mufflers deleted, M/T's, spare removed from trunk, and cooled off the engine with covers off and fans on top of engine and in front of the car. When I raced July 4 everyone was saying they were at least .1 off their normal times due to the high DA (for us) of 14-1500'. You might get that 10 second slip this winter when you get some good air.

Grip Grip

So you picked up 3 mph in 1k' higher DA by using 109 over the 90 octane & Torco. I think that needs to be my next mod.

Velociabstract

It won't speed you up IMO unless you "need" the octane. My car is faster with 93 than 100. It's a good test of what's going on …. or not.

Les

Dr Matt

Yep, but you need a tune for 109 specifically as it is an oxygenated fuel. It will be way too lean if you try to run it on your pump gas tune. VP MS 109 is the highest octane unleaded you can buy. There is definately more power in my tune as well. If you look at the dyno graph in the link below you can see the AFR is pegging the wideband at 10.3. (Still cant figure out why I used to be able to upload images here but now can't so here is a link to my dyno graph)

http://i205.photobucket.com/albums/b...ps2f6bc1b6.jpg

That AFR reading is after the cats so it should be 11.5-12. Instead, the actual AFR is in the 9's. I also set up a system to drain my fuel quickly and easily so I get ALL of the gas out before adding the 109. Hope to get the tune sorted out before Labor Day weekend as ther eis probably another 30 RWHP there but I'm not optomistic it will happen.

Grip Grip

Got it. I've had pretty good luck with 93 and torco, but I like to use the higher octane fuels (non-oxygenated) when I run the 1/2 mile events for safety.





I don't see me comitting to draining the fuel in order to run the 109. I drive the CL to the track with all the gear in the trunk, so for me it's a more casual hobby. I don't even bracket race it, I just stick to the test and tune.

As for posting photos, on the photobucket look for "Links to share this photo" and click on the last option "img". Left click on the link next to "img" and it should copy the address. If it doesn't, right click and copy the link address. Then just right click again and select paste in the body of the post. That's it.

Dr Matt

OK, in the past i was clicking on the image icon at the top of the reply box and pasting the coppied link. Tried just copying & pasting rather than selecting the image icon above &.......




Yay, it worked!

Grip Grip

Sweet! Glad you got it working, as I'm tired of looking at those damn links.

radride

If you're not tuned for the higher octane then you won't really make any more power. You might actually lose power as the higher the octane, the harder it is to burn. Try putting the stock tune back in and going back to the track and see what you run. Better yet, go to a dyno and see if the tune actually gave you more power. Maybe you have a boost leak and not making anymore power. Who knows.


R.K.

kamilclk430

Seems like you should have been going closer to the 11.0 mark if not even cracking a 10s pass the way your car was running stock. Out of the box it was fast, the ECU/TCU tune should have made the biggest dif off all mods anyone could get other than dif turbos.

kamilclk430

You sure? I think higher octane on these cars tune or no tune will pick up power.

RaceHorse

I know my car never had a race gas tune and every track event (3 of them) I used ms109. The car trapped between 124-127 mph. I totally agree with you, based on results not theory.

radride

To an extent. If the timing map hasn't been adjusted to accomidate the higher octane, you won't be able to utilize it to its full potential. Otherwise, tuners would be out of business.

R.K.

Speedriven1

These cars are very sophisticated and will detect octane variations and make adjustments to a certain extent. A tuned 600/65 for 93 will pick up power if 100 is used, but anything more will actually slow it down. More octane isn't always better, if your not tuned for it, it will run pig rich.

Dr Matt

If you are tuned for pump gas and put in MS109 it does not suprise me you run faster, but that does not mean it is safer. VP MS 109 is oxygenated and has a lower specific gravity that pump gas (less actual fuel molecules for a given volume of fluid) so if you put it in without a tune to compensate for it you will be running leaner, period. Leaner makes more power, until it causes melted pistons or valves. The correct way to run MS 109 is to have a proper AFR and add boost &/or timing to take advantage of it's excellent detonation resistance.

This is based on physics, and the reason why most cars, even carburated N/A cars will run faster when you put MS 109 or URT in them without a tune. I wouldn't mind running a little lean on some vehicles, but never on a forced induction car.

Like Marcin said, more octane is not always better. Swap pump gas for C-16 on a 93 octane tune and most vehicles will fall on their face.

RaceHorse

I don't disagree with what you are saying, but I guess it all depends on how lean your tune is for starters before running the MS 109. With your setup your tune shows a very rich AFR with your intake tubes. If you were to run MS 109 (current tune) do you think it would lean it out so much that it would be dangerous? What baffles me is how Grip added a tune, and octane booster and didn't see any significant gain in MPH. That doesn't add up.

Dr Matt

Mine was rich on the 109 tune. Never tried to Dyno the pump gas tune.

I agree it seems like he should have picked up more MPH, but I personally don't have enough track time with my CL yet to know if it was due to the difference in DA or if his car really was underperforming.

Grip Grip

It appears the DA was likely the culprit. I dyno'd the car today on the same DynoDynamics dyno that I ran a baseline on a month ago and it's picked up power.

Stock the car hit 509HP / 655TQ, and it was 85-90F. The HP number is from the first pull, and the TQ number was from the second. The TQ didn't register on the first run. The car dropped 10HP from pull 1 to pull 2, so my guess is the 655TQ would have been 665.

Today it got 558HP / 720TQ, temp was around 70F. Gains were 49HP and 65TQ. Air/Fuel was mid 10's across the board. Is that in line with what other's are seeing for ECU/TCU?