1/4 mile test. Is this right? Convertible steptronic

[rbdazzled]

Hi guys,

So I wanted to see what my car can do down the 1/4 and did 2 runs. The first was the best at 13.0@108. Seemed pretty good except 60ft wasn't great. Seemed to grip quite well.

Mods are

Jb4 map 2 on 98oct
DP
DCI
Front mount
CP

It's steptronic and a convertible.

For those mods shouldn't my mph be greater than 108 based on theoretical hp? Sure a better reaction time and 60ft should get 12s but I still feel that these numbers don't stack up?

Anyone have similar experiences?

[choppedliver]

Seems a bit slower than expected.

I've done almost exactly the same time with a tune only. I now have DPs and IC and I would expect 12.6@112 or similar. The car seems a lot faster.

B

[rbdazzled]

Yeah thats what I thought. Guess i need to get some logs to see whats going on.

[rbdazzled]

Mind you, what was your reaction and 60ft times?

[JB4-335]

Originally Posted by rbdazzled

Hi guys,

So I wanted to see what my car can do down the 1/4 and did 2 runs. The first was the best at 13.0@108. Seemed pretty good except 60ft wasn't great. Seemed to grip quite well.

Mods are

Jb4 map 2 on 98oct
DP
DCI
Front mount
CP

It's steptronic and a convertible.

For those mods shouldn't my mph be greater than 108 based on theoretical hp? Sure a better reaction time and 60ft should get 12s but I still feel that these numbers don't stack up?

Anyone have similar experiences?

That sounds about right for map 2 (14.5psi). With those mods I'd put some E85 and add the backend flash and try map 5.

I ran 11.93@115mph in my old 135i vert. Similar mods but I had some race fuel and methanol injection.

[rbdazzled]

Originally Posted by JB4-335

That sounds about right for map 2 (14.5psi). With those mods I'd put some E85 and add the backend flash and try map 5.

I ran 11.93@115mph in my old 135i vert. Similar mods but I had some race fuel and methanol injection.

Thats awesome! So MHD? Thats the only one I know of for backend flashes. Just an OTS map?

Did you do that with a stock LPFP?

[JB4-335]

There was no MHD back then in 2012 when I ran that time. It was my own backend flash via COBB with a custom map 6 curve.

I had a stock LPFP but ran some MS109 race fuel.

[choppedliver]

Originally Posted by rbdazzled

Mind you, what was your reaction and 60ft times?

The mph is the key indicator of power, 60ft etc, only affect ET. I did a bunch of 108mph, but get 13.0 was much harder.

B

[rbdazzled]

Originally Posted by choppedliver

The mph is the key indicator of power, 60ft etc, only affect ET. I did a bunch of 108mph, but get 13.0 was much harder.

B

yeah so im wondering how you managed that mph with only a tune. unless you have one of those freak engines?

[froop]

Whether someone has just a tune
or a tune and also supporting mods doesn't really matter that much over a single 1/4 mile run. What really matters when it comes to peak power is what the tune actually is. No two tunes are equal. It's possible that someone could have a more aggressive tune without supporting mods and yours just happens to be less aggressive.

If you want to go faster you need a more aggressive tune. Period.

In my Steptronic vert I've run maybe slightly faster than you with only a JB4 on map 5 with only DCIs but I was on an E35 mix. As JB4335 said, you need some increased octane to increase the aggressiveness of your tune and you should run a faster time.

In a nutshell. Supporting mods like intakes, exhaust, FMIC, fueling, fuel, etc don't make power. They only support higher levels of power. It's your tune that makes the power.

[rbdazzled]

Originally Posted by froop

Whether someone has just a tune
or a tune and also supporting mods doesn't really matter that much over a single 1/4 mile run. What really matters when it comes to peak power is what the tune actually is. No two tunes are equal. It's possible that someone could have a more aggressive tune without supporting mods and yours just happens to be less aggressive.

If you want to go faster you need a more aggressive tune. Period.

In my Steptronic vert I've run maybe slightly faster than you with only a JB4 on map 5 with only DCIs but I was on an E35 mix. As JB4335 said, you need some increased octane to increase the aggressiveness of your tune and you should run a faster time.

In a nutshell. Supporting mods like intakes, exhaust, FMIC, fueling, fuel, etc don't make power. They only support higher levels of power. It's your tune that makes the power.

Fair enough. I have run 30% e85 before but had problems afterwards with the car going into limp mod. Is that just a sign that it requires a better LPFP? It definitely felt quicker though.

[Alpha Trion]

gotta remember verts are about 200kgs (from memory) heavier than the coupes.. and that will slow you (and me) down!

[rbdazzled]

Originally Posted by Alpha Trion

gotta remember verts are about 200kgs (from memory) heavier than the coupes.. and that will slow you (and me) down!

We just need to lose some mass

[choppedliver]

Originally Posted by rbdazzled

yeah so im wondering how you managed that mph with only a tune. unless you have one of those freak engines?

It was winter so perhaps the car was making more power. The tune was a procede tune so perhaps that's a factor.

[froop]

Originally Posted by rbdazzled

Fair enough. I have run 30% e85 before but had problems afterwards with the car going into limp mod. Is that just a sign that it requires a better LPFP? It definitely felt quicker though.

30% E85 on map 5 or on map 2?

A limp mode by itself doesn't tell really much of anything. You need to read the actual code to see if it's fueling, misfire, boost, etc etc.

[rbdazzled]

Originally Posted by froop

30% E85 on map 5 or on map 2?

A limp mode by itself doesn't tell really much of anything. You need to read the actual code to see if it's fueling, misfire, boost, etc etc.

It was on map 5. It ran really well for a while, then limp. Shut it off for a few minutes, its good again for a while, then limp. Then on the way home it just turned off. Tried starting but all it did was turn over. Left it for a few days and all good again. Have never ran e85 on map 2. Actually, havent ran e85 since that time at all.

[froop]

Originally Posted by rbdazzled

It was on map 5. It ran really well for a while, then limp. Shut it off for a few minutes, its good again for a while, then limp. Then on the way home it just turned off. Tried starting but all it did was turn over. Left it for a few days and all good again. Have never ran e85 on map 2. Actually, havent ran e85 since that time at all.

Maybe your LPFP is a bit weak and it was running out of fueling so went into a limp mode. A good stock LPFP should be able to hand up to E60-70 with a backend flash and my car handles E35 without any backend flash no problems on map5.

If you experience issues with E85 you need to datalog to make sure that the car is getting sufficient fueling. I'd recommend either reducing the E85 percentage and/or get a back end flash and/or getting a LPFP upgrade.

[rbdazzled]

Originally Posted by froop

Maybe your LPFP is a bit weak and it was running out of fueling so went into a limp mode. A good stock LPFP should be able to hand up to E60-70 with a backend flash and my car handles E35 without any backend flash no problems on map5.

If you experience issues with E85 you need to datalog to make sure that the car is getting sufficient fueling. I'd recommend either reducing the E85 percentage and/or get a back end flash and/or getting a LPFP upgrade.

That's what I thought and will be next on the list. Anyway, my car stalled coming home today. I wonder if my battery died. Would turn over start and then stall. Then not turn over and the dash flickered and went strange, then turned over but wouldn't start, then just wouldn't turn over. Any recommendations for a battery that's good and doesn't cost a fortune? Also best way to register it? Cheers

[froop]

Originally Posted by rbdazzled

That's what I thought and will be next on the list. Anyway, my car stalled coming home today. I wonder if my battery died. Would turn over start and then stall. Then not turn over and the dash flickered and went strange, then turned over but wouldn't start, then just wouldn't turn over. Any recommendations for a battery that's good and doesn't cost a fortune? Also best way to register it? Cheers

That's very strange. Your car wouldn't just die when it is running even if your battery is dying as the alternator will keep it running. If you stalled it because you have a manual and your battery is kaput then that would make sense. Possibly one thing that could cause that would be the battery cable recall where the terminal corrodes to the point it loses connection and your car will just lose all power suddenly, but then usually if that happens it's unlikely the connection will just come back.

As for a battery, really anything would be fine but it all depends on your uses. I just had NRMA install one of their batteries in my car for $264 last week because one of the cells in my battery died. It drove with no problem but it wasn't holding any charge and was overheating. The NRMA battery is an 80aH which is the same size as the stock battery so fits in perfectly. I coded it myself using the Carly for BMW App. If you want to, I can just code your battery for you using the app and my cable since I've already purchased the battery coding module on it. I may as well use it.

But yeah, if you're just looking for a stock battery, really anything that's the correct size so the bracket will hold it down and the right aH rating so you don't have to worry about it running out of charge if you leave it a couple weeks without driving it on holidays. Otherwise if you're looking at reducing weight there are quite a few options to choose from as well like lighter weight AGM batteries which are similar in cost but a lower aH rating or even an LiPo battery (which cost A LOT).