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Recently took my car out to the local drag strip completely stock and ran a 11.74 @ 120mph using race start (will post time slips when i get back in car)
My question is, is it possible to foot brake these cars and if so how? Seems as if everytime i try it immediately throttle cuts and wont allow it. Also what have you all seen as the best method? Race start or foot brake?
'03 E55, Range Rover Sport Supercharged, Ducati 748R
Brake boosting yields the best results but it will bog if rpms aren’t high enough and go into temporary limp mode if you get close to 3k rpm or if you try to brake boost twice in a row (ie; initiating a burnout or practice launch then trying to immediately do it again at the starting line). It also won’t let you hold a steady rpm so you have to catch the launch as the rpms climb. It’s impossible to focus on the tree and your launch at the same time so avoid the tree if you’re trying to get a time. This car is fun but awful for launching from a dig. It’s the definition of dyno/roll-race queen.
Last edited by chiromikey; 07-26-2018 at 01:53 PM.
My best is still always with Race Start; trying to brake boost is too finicky and it typically ends up bogging off the line
Thats a good run in stock form though!! What was your 60 ft?
So no RS start and you find this will give you better times. Will this wear out your brakes sooner vs doing RS start?
I have tested it many times my best 0-60 with RS is 3.27 and with brake boosting 3.11, 3.12, 3.14 it's not much of a difference in 0-60 but for some reason in the 1/4 mile brake boosting always ends up just about 2 tenths of a second quicker...I dont know if .1 tents in 60ft translates to more tenths in the quarter...maybe somebody does?
I have tested it many times my best 0-60 with RS is 3.27 and with brake boosting 3.11, 3.12, 3.14 it's not much of a difference in 0-60 but for some reason in the 1/4 mile brake boosting always ends up just about 2 tenths of a second quicker...I dont know if .1 tents in 60ft translates to more tenths in the quarter...maybe somebody does?
Makes sense...usually .1 in 60 ft improvement equals .15-.2 improvement in the quarter. At least that's what it was when I owned a Vette.
I have tested it many times my best 0-60 with RS is 3.27 and with brake boosting 3.11, 3.12, 3.14 it's not much of a difference in 0-60 but for some reason in the 1/4 mile brake boosting always ends up just about 2 tenths of a second quicker...I dont know if .1 tents in 60ft translates to more tenths in the quarter...maybe somebody does?
I couldn't get consistency out of brake boosting when trying to launch against a tree... for me to monitor RPM's and the tree when 1/4 mile racing was too much. My RT usually sucked.....
I've gotten comfortable with RS and having the timing down sufficient to get repeatable 1/4 mile RT times (~ 0.2/0.3 RT)
I do have the Performance VBOX and may try logging different launches between brake-boost and RS to see if there is an improvement in 60 feet times.. but those times I did use brake-boost I couldn't exceed approximately 2500 rpm before bogging off the line.
I've done multiple 1/4 mile runs in 93° temps (not ideal I know) but my traps and times where consistent regardless of what method I used.... 11.8/11.9 @ 120 with 1.8/1.9 60 ft times...
Until someone can tune these TCU's properly I don't think it'll make much difference which method we use as there is too much intervention going on in the first two gears for it to matter...
That's my 2 cents of course, your mileage may differ...
Last edited by brutus_tx; 07-30-2018 at 04:22 PM.
Reason: duplicity of text
'03 E55, Range Rover Sport Supercharged, Ducati 748R
Originally Posted by brutus_tx
I couldn't get consistency out of brake boosting when trying to launch against a tree... for me to monitor RPM's and the tree when 1/4 mile racing was too much. My RT usually sucked.....
I've gotten comfortable with RS and having the timing down sufficient to get repeatable 1/4 mile RT times (~ 0.2/0.3 RT)
I do have the Performance VBOX and may try logging different launches between brake-boost and RS to see if there is an improvement in 60 feet times.. but those times I did use brake-boost I couldn't exceed approximately 2500 rpm before bogging off the line.
I've done multiple 1/4 mile runs in 93° temps (not ideal I know) but my traps and times where consistent regardless of what method I used.... 11.8/11.9 @ 120 with 1.8/1.9 60 ft times...
Until someone can tune these TCU's properly I don't think it'll make much difference which method we use as there is too much intervention going on in the first two gears for it to matter...
That's my 2 cents of course, your mileage may differ...
Thats a spot on assessment! With tires I can get pretty consistent low 1.7s using RS (which could probably be improved at a better track). While these 60ft times suck **** in the world of drag racing, it’s top shelf for this platform in general but even more so for using RS.
Have you seen a measurable difference between your street and race gas tunes? What’s your best 1/4mile numbers on each?
While I can't answer this particular question, I can impart some of what I've found out in recent successive quarter mile testing over a two week period between my car (stock) and one that recently received a tune/catless dp upgrade
At the start of testing both cars where at an identical state of tune... stock
Ignore the actual numbers as its not the intent of this post, its just meant as a means to compare both tunes
My car made 577 hp / 625 tq
My partner in crime made 582 hp / 619 tq
Both cars are 2014 E63S's...
We made multiple passes at Royal Purple Raceway on 22nd June, with the following time slip indicative of all races. Both cars where consistent. My car (460) was a little slower out of the hole, but consistently just a little faster on the top end.
consider me the baseline for this little experimemnt...
a week later, after the other vehicle received a Eurocharged Tune and Catless DP, we revisited the raceway with the following results.
I'm car is 258, my friend's is 120.
Proof is in the pudding as they say.
A week later under very similar track conditions (think Hades in the summer) and its obvious my friends car has seen a tangible increase in performance.
He picked up 3 tenths on his quarter mile time and 2 mph in his trap.
That may not sound like much, but the week previous it was a great lineup with each race a toss up who would win... now, all I ever see is his tail lights running down the track.
When we launch, he gets the hole shot and jumps out in front of me... once we get rolling we are neck and neck all the way to the end, but by then the damage is done. While we have the same trap now, he has me down low with the additional torque he received via his new tune.
My only recourse is to get a tune/catless DP of my own and then revisit the track. I don't have an opinion either way on which tune is the best, but I may opt for a different brand to see what, if any difference, there is between the various tunes.
I don't have an overlay of my friends new tune on a dyno... my apologies for that. It would be interesting to see the area under the curve.
I hope this helps and stimulates further discussion...
'03 E55, Range Rover Sport Supercharged, Ducati 748R
Good info and my tune results are fairly similar. My interest lies in the difference between a tune and a race gas tune so I’m hoping 727 will come back with similar objective info.
While I can't answer this particular question, I can impart some of what I've found out in recent successive quarter mile testing over a two week period between my car (stock) and one that recently received a tune/catless dp upgrade
At the start of testing both cars where at an identical state of tune... stock
Ignore the actual numbers as its not the intent of this post, its just meant as a means to compare both tunes
My car made 577 hp / 625 tq
My partner in crime made 582 hp / 619 tq
Both cars are 2014 E63S's...
We made multiple passes at Royal Purple Raceway on 22nd June, with the following time slip indicative of all races. Both cars where consistent. My car (460) was a little slower out of the hole, but consistently just a little faster on the top end.
consider me the baseline for this little experimemnt...
a week later, after the other vehicle received a Eurocharged Tune and Catless DP, we revisited the raceway with the following results.
I'm car is 258, my friend's is 120.
Proof is in the pudding as they say.
A week later under very similar track conditions (think Hades in the summer) and its obvious my friends car has seen a tangible increase in performance.
He picked up 3 tenths on his quarter mile time and 2 mph in his trap.
That may not sound like much, but the week previous it was a great lineup with each race a toss up who would win... now, all I ever see is his tail lights running down the track.
When we launch, he gets the hole shot and jumps out in front of me... once we get rolling we are neck and neck all the way to the end, but by then the damage is done. While we have the same trap now, he has me down low with the additional torque he received via his new tune.
My only recourse is to get a tune/catless DP of my own and then revisit the track. I don't have an opinion either way on which tune is the best, but I may opt for a different brand to see what, if any difference, there is between the various tunes.
I don't have an overlay of my friends new tune on a dyno... my apologies for that. It would be interesting to see the area under the curve.
I hope this helps and stimulates further discussion...
awesome post and great objective info --- thank you!
You still here? Hoping you can answer the question above about difference between pump and race gas.
Sorry about the late reply..I was on vacation just got back 😁
626 whp 676 wtq were the numbers on 91 octane
793 wtq and 653 whp on 105 octane race gas tune.
the difference is day and night...in the 1/4 mile I picked up 2 tenths with just race gas
Sorry about the late reply..I was on vacation just got back 😁
626 whp 676 wtq were the numbers on 91 octane
793 wtq and 653 whp on 105 octane race gas tune.
the difference is day and night...in the 1/4 mile I picked up 2 tenths with just race gas
How often did you run leaded fuel? Also are you replacing the sensors, due to lead contamination?
I just had my sensors replaced..so Im not doing leaded anymore...also got some ms109 today so I can tune my car tomorrow (just upgraded turbos..custom tune)
from what I was told at the shop that did my work...even 1/4 tank can destroy oxygen sensors...
1 part 120 Octane leaded to 3 parts premium unleaded several times last year, my O2 sensors are still working fine
I've stopped using race fuel all together. I dump methanol into the fuel tank now, ~15% - Gets rid of catless smell. Much cheaper than race fuel. Better for environment. I'm able to run 100 octane tune. No more leaded or race fuel for me.
Your fuel pumps must be able to handle the added flow, with Factory turbos not a problem.
'03 E55, Range Rover Sport Supercharged, Ducati 748R
Originally Posted by e65
1 part 120 Octane leaded to 3 parts premium unleaded several times last year, my O2 sensors are still working fine
I've stopped using race fuel all together. I dump methanol into the fuel tank now, ~15% - Gets rid of catless smell. Much cheaper than race fuel. Better for environment. I'm able to run 100 octane tune. No more leaded or race fuel for me.
Your fuel pumps must be able to handle the added flow, with Factory turbos not a problem.
Do you carry a 3 gallon can of meth with you each time you fill up?
07-26-2018, 01:25 AM
