Ok so a buddy and I did a data log through a couple gears two nights ago and got some consistent, but weird results. First here are the mods on the car:

exeddy twin HD
Buschur 3" turbo back w/cat delete
HKS 272 cams
Buschur Tune
walbro 255
Buschur MBC
Buschur filter
9 BOV

Car has 86k on it changed oil and flushed coolant 2 weeks before these pulls just FYI

So we did a 3rd gear pull, starting from 3K rpm, and banged into 4th and continued to redline. On the log, the cell right after the shift from 3-4 we started seeing a high count of knock of around 8-9 per cell and dropping off to zero after about 15 cells. Obviously while this happened, we could see the car pulling timing with -3 being the worst count.

We did another 3rd gear pull starting at roughly 3k rpm, and got the same result. The car was tuned at roughly 24 psi. I believe by looking at the defi gauge i have, and recording the runs, that the car is running around 23 psi. So slightly lower pressure than it was tuned at.


We logged the car right after i got the tune which was about a year ago, and it was 100% clean throughout all gears, so this is different compared to when i first got it back from buschur.

Any help with any of these issue would be greatly appreciated.

I have the logs saved if anyone would want to take a look.

-Ryan

 

I'm working on getting data from the pulls tonight. Any help would be greatly appreciated

 

u have a wideband?

 

sure don't = / Ill be posting the data soon, And im not sure what has changed since then ?? I know that every time i have tracked the car that i pull a 1.7 60 ft shift well and only do a 13 flat and trap 106 - 107 so i know the car isn't running right with the mods im running = /

 

please disregard this dat. The correct data can be seen down below.

 

not enough info in that log..would need to see timing numbers atleast..but have u done a boost test first?

 

dangit, i thought i had the other columns included. Sorry im a little new at posting pictures like that. Ill have the full log on shortly, and FYI i boost leak tested the car 8 months ago with no leaks.

 

That is far too long to go without doing a boost leak test. Do that before you do another log and report back.

 

I will do a boost leak test again this weekend. Would a boost leak help explain why i start getting a knock sume o**** over 3 and up to 13 and pull timing when i switch gears>? Thanks for the help you two so far. Im working on formating this data. Macs make this process a PITA!

 

Ok here is the data from the 3rd to 4th shift. I will do a boost leak test this weekend and re log and hopefully this will solve the problem. In the mean time any help or advise would be grealy appreciated.

-Ryan

 

I honestly don't know much about tuning, but if you have a leak, the hot air from the turbo over working itself could cause a knock. I could be 100% wrong though.

 

ok my twin brought up the boost leak tester from lexington to cinci, and i will boost leak test the car tomorrow and data log again and post results. Who knows, maybe we will find a leak, and the log will show no knock!!!