Any experts out there? Would you mind giving me your opinion of my TTS Datamaster logs?

My car is a '95 ZF6, Corsa Exhaust, K&N Filter, 1.6 LT-4 Roller Rockers with LT-4 springs and hardware.

Seems to be a little rich to me. Wondering if it's worthwhile to purchase a custom mail order tune.

Thanks


http://www3.ns.sympatico.ca/krichar/temp/Testdata.zip

 

Might be worth a tune. I am no expert (by any means) but I see that you are getting knock retard in 3rd and 4th gear at around 4700 RPMs. The strange thing is that you are not over reving the valve train, so I don't know what could cause it.

Don't do a mail order tune. If you are going to spend the money, have someone dyno tune it. I am hesistant about the "one tune fits most" mail order tune theory. Would you let a doctor diagnose you over the phone? Same principal in my book.

At least here is a bump for the experts to look at it. I will look at it more tomorrow and see what I can come up with..

Good luck,
Scott

 

Thanks for taking the time to look Scott.

Dyno tune is out of the question for me. Nobody within several hundred miles of me has a chassis dyno or know what to do with our PCMs.

The other option I'm toying with is using VE Master and doing it myself. I just figured the mail order guys would have something on file that's close to my setup. The biggest change is 1.6 rockers which isn't all that odd.

As for the knock....it might be false knock but I wouldn't be surprised if it's detonation. Funny how it didn't do it in the lower gears? Maybe I need the LT-4 knock module as well?

Thanks

 

Yeah, it could be false knock considering that the valve train was upgrade (could be nosier and the knock sensor is interpreting that as detonation).

What about buying and getting installed a wideband O2 setup. You can get one for less than $300 dollars. But you won't know for sure how rich or lean an engine is running with the narrowband 02 sensors (only tells you that is above or below 14.7 AFR).

A little rich is better for performance anyways with the best rich torque and best lean torque normally between 12.2 - 12.8 AFR. However, the spark retard is going to really hurt your performance. You need to determine if the knock is real or not. If it is real knock, don't use a bandaid like the LT4 knock sensor, fix the problem.

Maybe ask in tech and performance about whether you need to get a LT4 KS with your valvetrain upgrades. I don't know if they have experience with it over in that forum. I wish I could help you there but I don't have the experience with LT4 valve train swaps.

Let me know how it goes and sorry I couldnt' be of more help.

GL,
Scott

EDIT: Sounds like some MAF ECMS are getting good results from VEmaster. This is with a cam swap but maybe VEmaster is worth a shot!

http://forums.corvetteforum.com/show....php?t=1430011

 

I ran my logs through VEMaster and it's telling me I'm rich at lower RPM right across the MAP range. It also tells me I'm lean at the upper RPM right across the MAP range. So, that *might* be the reason for the knock counts - a little on the lean side on the upper end. This is what I expected from 1.6 rockers and exhaust...a little less efficient at the bottom but more efficient at the top.

I'll give VEMaster a try and see if it gets a little closer. I wish I had a dyno close by because more than likely my PE tables are a little lean as well.

Now, do I tell VEMaster to tune for 124 trims or 128? Hmm, what you think?



******** Fuel trim table statistics ********

Cell # recs map range rpm range
min LTerm/avg LTerm/max LTerm (left and right)

0: 0 map: 0 - 37, rpm: 0 - 900

1: 28 map: 0 - 37, rpm: 900 - 1400
119/119/119 117/117.464/118

2: 1019 map: 0 - 37, rpm: 1400 - 2200
112/115.438/119 116/118.753/119

3: 23 map: 0 - 37, rpm: 2200 - 7000
120/120.348/125 120/120.261/124

4: 4 map: 37 - 57, rpm: 0 - 900
126/126/126 125/125/125

5: 41 map: 37 - 57, rpm: 900 - 1400
116/116.049/117 118/118/118

6: 656 map: 37 - 57, rpm: 1400 - 2200
116/116.011/118 119/119.003/120

7: 61 map: 37 - 57, rpm: 2200 - 7000
118/118.262/127 120/120.131/126

8: 0 map: 57 - 77, rpm: 0 - 900

9: 16 map: 57 - 77, rpm: 900 - 1400
118/118.188/121 120/120/120

10: 90 map: 57 - 77, rpm: 1400 - 2200
119/119.244/121 121/121.033/124

11: 16 map: 57 - 77, rpm: 2200 - 7000
128/128/128 127/127.063/128

12: 0 map: 77 - 104, rpm: 0 - 900

13: 9 map: 77 - 104, rpm: 900 - 1400
125/125/125 128/128/128

14: 10 map: 77 - 104, rpm: 1400 - 2200
125/125/125 128/128.7/129

15: 6 map: 77 - 104, rpm: 2200 - 7000
131/131/131 131/131/131

16: 327 map: 30.5177 - 32.9662, rpm: 702 - 826
118/118.153/119 116/116.003/117

 

I normally use 125 or 126. You want your BLM's to be a bit below 128, so at WOT your PCM will lock in at 128. It will adjust up to 128, but not down to 128.

-Mike