1/4 Mile Results: Helper Spring, 100 Octane Fuel & Street Tuning

TurboQueef · 09-17-2005, 08:35 AM

Had a good trip to the track last night. Traction was very poor to start with then it got worse.

Here is a quick summary of the effect of a wastegate helper spring and 100-octane fuel on my 1/4-mile performance.

Best pass before helper & fuel: 13.21 @ 101.84 (1.7970 60 foot)

Best pass with helper spring and 100 octane: 13.15 @ 103.70 (1.8431 60 foot)

My take on the matter: Traction problems kept me from breaking into the 12's but my MPH is still a bit low. The helper spring and GT 100 fuel did make 1.8 to 2 MPH improvement but still not hitting my target.

NOTE: This track is SLOW, CoreySTi04 joined us at the track, he was way off his best time.

For you Data-lovers.. I have attached a few logs for your review (compare before and after helper spring / 100-octane fuel)

**WolfPlayer** · 09-17-2005, 11:53 AM

Thanks a lot for the data logs. Love looking at data. Things look pretty good, IMHO. The only oddity I saw was that your DAM was at 0.75 instead of 1.0. Seems like you redid your stock Primary Ignition table and made it much more aggressive such that there is less dependence on the dynamic advance. True?

AFRs look fine and timing is ok. With a harder launch you'll be running a 12.99. With colder weather you should be able to get that down to 12.8x or better. If Jay (jaygoesfast) was driving and powershifting then a 12.6 would be right there.

... I can only imagine what these cars would be like with an automatic and a high stall converter. Mid-12s would be easy easy easy.

t

TurboQueef · 09-17-2005, 01:45 PM

Quote:

Originally Posted by WolfPlayer

Thanks a lot for the data logs. The only oddity I saw was that your DAM was at 0.75 instead of 1.0. Seems like you redid your stock Primary Ignition table and made it much more aggressive such that there is less dependence on the dynamic advance. True?
t

Wolf,

True,,, I pulled a few data-logs after I added the 100 octane fuel. I wanted to see if the ECU would adjust quickly. It did not so I added a total of 2 deg. across the entire primary ignition map to help things out.

The track was not very sticky from the start and got worse as the night proceeded. I really wish I could have made a couple of 1.680 60' launches... that would have put me in the high 12's. I was loosing so much traction, I had to check my axles this AM to insure one wasn't broken.

I may take a trip to one of the "sticky" tracks down south next week. I will keep you all posted on any progress I make getting into the 12's

gt42sti · 09-17-2005, 07:48 PM

Nice job,

Too bad you couldnt get the DA and timing up to speed. Also, I wonder if the boost can be moderated with the helper spring mod. Are there any specs on this helper spring?? Are you running the stock intake?

TurboQueef · 09-17-2005, 08:23 PM

Quote:

Originally Posted by gt42sti

Nice job,

Too bad you couldnt get the DA and timing up to speed. Also, I wonder if the boost can be moderated with the helper spring mod. Are there any specs on this helper spring?? Are you running the stock intake?

Hi... even though the DA was reduced, I think the overall timing advance was good. As far as the spring mod.. I used part # SP-9618 from Home Depot. The specification is:

5/8" x 3-1/4" x .072 with a maximum safe load capacity of 19.1 lbs

I am running the stock intake with the silencer removed and a drop in K&N filter.

The only way to "moderate" the helper spring is by tweaking the Waste Gate Duty Cycle (WGDC) and BOOST maps. I did need to adjust things as noted in this post: http://www.iwsti.com/forums/showthread.php?t=31952

Thanks for the reply...

TurboQueef · 09-25-2005, 03:30 PM

Quote:

Originally Posted by gt42sti

Nice job,
Too bad you couldnt get the DA and timing up to speed.

Interesting note: The DA went down to .74 then up to .88 during my 1/4 miles runs on 100 octane fuel. After I ran out of the good fuel, I changed back my map to normal stage 2 timing. I ran 300 miles of 93 octane this past week and was surprised to find the DA did not change back to 1, it seemed to be stuck on .88

I decided to tinker around a bit today... I added 070 to my Real-time primary ignition map, reset the ECU and headed out. I got the DA back to 1 then made a few pulls. The timing went back to where I want it with no knock or pull of DA. I turned the real-time map into a base map and flashed it to the ECU. I then made another fourth gear pull and all looks good. My AFR is a bit lean due to the humid rainy wx here in MI.

I have attached the last two pulls using the new base map.

SUL

jays05 · 09-25-2005, 04:18 PM

You're running a lot more timing than I am around 4000rpms in the 4th gear pull log. I have 17 degrees at 4000 with 19.5psi and 11.5 AFR with no knock. Do you need so much timing there?

TurboQueef · 09-25-2005, 05:11 PM

Quote:

Originally Posted by jaygoesfast

You're running a lot more timing than I am around 4000rpms in the 4th gear pull log. I have 17 degrees at 4000 with 19.5psi and 11.5 AFR with no knock. Do you need so much timing there?

I see around 22 degrees at 4K, it seems to pull much better with the timing that high. I am wondering if my launch problems are related to too much power at launch, (around 4 to 5 K RPM), maybe I would be better off dropping it a bit.

gt42sti · 09-25-2005, 07:09 PM

Quote:

Originally Posted by TurboQueef

I see around 22 degrees at 4K, it seems to pull much better with the timing that high. I am wondering if my launch problems are related to too much power at launch, (around 4 to 5 K RPM), maybe I would be better off dropping it a bit.

My timing with 92oct at 4k is ~19, pulls hard, boost 18.7, loads 3.1. This is my daily driven setup. With 100oct on board...I do think you could hit 22 but it may be better to ramp that up later in the rpm range.

Update on the spring with my car. I put the 11lb spring on and have had fantastic results. I will post them.

STirish · 09-26-2005, 08:16 AM

How long were you in the staging lanes? Your initial IATs could have been very high causing some knock.

TurboQueef · 09-26-2005, 04:16 PM

Quote:

Originally Posted by STirish

How long were you in the staging lanes? Your initial IATs could have been very high causing some knock.

Actually it was a cool evening, my IAT's were 95 cooling to 72. I just noticed that from the very first pass, my DAM was reduced (even before I made the pass, as I was driving onto the track). I bet it reduced on the way to the track and then never recovered.

Even though my current map is showing around 22 degrees advance at 4K, I plan to test it some more. So far, no knock or reduction of DAM and it pulls so much harder from the launch

jays05 · 09-27-2005, 03:55 AM

You need a lot of knock to get the DAM to reduce.

TurboQueef · 09-27-2005, 03:10 PM

Quote:

Originally Posted by jaygoesfast

You need a lot of knock to get the DAM to reduce.

Besides knock, are there any other factors that could cause the DAM to reduce?

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09-17-2005, 11:53 AM	#2
WolfPlayer Moderator & ECU Tech Car: 05 CGM STI Fav Mod: mo boostaz Location: Fredneck, MD Posts: 3,759 IWSTI Addict since: Jun 2004 Trader Rating: (6)	Thanks a lot for the data logs. Love looking at data. Things look pretty good, IMHO. The only oddity I saw was that your DAM was at 0.75 instead of 1.0. Seems like you redid your stock Primary Ignition table and made it much more aggressive such that there is less dependence on the dynamic advance. True? AFRs look fine and timing is ok. With a harder launch you'll be running a 12.99. With colder weather you should be able to get that down to 12.8x or better. If Jay (jaygoesfast) was driving and powershifting then a 12.6 would be right there. ... I can only imagine what these cars would be like with an automatic and a high stall converter. Mid-12s would be easy easy easy. t

09-17-2005, 07:48 PM	#4
gt42sti Junior STI Driver Car: Silver 04 STI Location: Eugene,Or Posts: 116 IWSTI Addict since: Oct 2004 Trader Rating: (0)	Nice job, Too bad you couldnt get the DA and timing up to speed. Also, I wonder if the boost can be moderated with the helper spring mod. Are there any specs on this helper spring?? Are you running the stock intake?

09-25-2005, 04:18 PM	#7
jays05 Spec C Club Car: Blue 05 STI Fav Mod: 4th gear wheelspin Location: Upstate NY Posts: 2,095 IWSTI Addict since: Nov 2004 Trader Rating: (0)	You're running a lot more timing than I am around 4000rpms in the 4th gear pull log. I have 17 degrees at 4000 with 19.5psi and 11.5 AFR with no knock. Do you need so much timing there?

09-26-2005, 08:16 AM	#10
STirish Spec C Club Car: '99 M3/'03 WRX Avant Fav Mod: Modification is wrong! Location: SLC, UT Posts: 1,026 IWSTI Addict since: Sep 2004 Trader Rating: (6)	How long were you in the staging lanes? Your initial IATs could have been very high causing some knock.

09-27-2005, 03:55 AM	#12
jays05 Spec C Club Car: Blue 05 STI Fav Mod: 4th gear wheelspin Location: Upstate NY Posts: 2,095 IWSTI Addict since: Nov 2004 Trader Rating: (0)	You need a lot of knock to get the DAM to reduce.