Timing on TVS

[ArtVandalay16]

I agree with you, but found it odd you posted your logs publicly for no plausible reason except doubt in VMP. Why not share with another tuner through PM.
I agree that Justin isn't the social type, vague can be an understatement. Lol

 

[jojobee]

Pull all 8 and take some pics.

This was number 8 which was incorrectly gapped and damaged.
Compression is 175

 

[Fun4me]

Is it taboo to post logs?:shrug:

 

[jojobee]

I agree with you, but found it odd you posted your logs publicly for no plausible reason except doubt in VMP. Why not share with another tuner through PM.
I agree that Justin isn't the social type, vague can be an understatement. Lol

The op asked what timing we were seeing with a tvs so i think its relevant to share with others what im seeing.
I did not do this to doubdt VMP but to fuel the discussion as timings are a concern for many.
My can run great on my VMP tune and have nothing bad to say about it, just sharing what i see.

 

[jojobee]

Is it taboo to post logs?:shrug:

If it is then i apologize but honestly i dont know why it would need to stay private especially when the car is running great.

 

[CPRsm]

Eh, I've only ever seen detonation close gaps so I wouldn't worry.
Areyou using a fual addictive?

Need better pics of the ground straps. The side and the back. Fuel rings are wrothless but you can still get an idea of cyl temp.

Did you pick up power when timing advanced?

 

[CPRsm]

Dp

 

[jojobee]

Eh, I've only ever seen detonation close gaps so I wouldn't worry.
Areyou using a fual addictive?

Need better pics of the ground straps. The side and the back. Fuel rings are wrothless but you can still get an idea of cyl temp.

Did you pick up power when timing advanced?

My dyno graph shows that where i saw the most agressive timing was at the point where power started to go down around 6800.

No additive except for the one already added by Petro Canada to make it a 94oct.

I was wondering why the plugs had a rusted look that i hadnt seen elsewhere.

Here are some better pics

 

[kevinp]

There is nothing wrong with posting logs, now posting other people's tunes would be a different story. Nothing wrong with trying to learn whats going on with your own car.

The brown color on the plugs is most likely from methyl tertiary butyl ether (MBTE), its an additive that is used to raise octane. Pretty sure its outlawed in the US at the pump but some additives still use it. Most likely your O2 sensors will have the same color. There are other additives that will color the plugs as well.

FWIW I have ran quite a bit of timing and never hurt anything (yet), running lean at high RPM can do more damage then spark, low RPM and high load can really tear stuff up with too much advance though. My timing looks a little more 'U' shaped the way I have it now.

IMO if you want to tone the tune down its way easier to just take the 10 minutes and swap the 90mm pulley back on, you enjoy lower IATs and less parasitic loss as well..

I have different tunes for different tires, pulleys, fuel and weather, plus dedicated track tunes that I use. If you can get a tuner to sell you a decent tune and include a tune file you can really dial things in with the SCT PRP software to your liking. You cant see or change anything related to the electronic throttle control, cam timing and a few other things at the racer level but you can do the fuel, timing, auto trans and a lot of other things. Pretty steep learning curve though, I have been tuning cars for 35+ years using all kinds of different engine management systems and the SCT software is a bit of a challenge - a lot to learn for just one car.

 

[jojobee]

Great answer, thanks
I already have an heat exchanger so i am not too worried about iat for now but i will sure datalog it my next time at the track.
Since im also only seeing 8-9psi with my setup i was contemplating the idea of getting a 79mm pulley.
As per Justin this should be fairly safe for me....still debating this.
Next summer ill forge the bottom end for long term reliability.

 

[kevinp]

Great answer, thanks
I already have an heat exchanger so i am not too worried about iat for now but i will sure datalog it my next time at the track.
Since im also only seeing 8-9psi with my setup i was contemplating the idea of getting a 79mm pulley.
As per Justin this should be fairly safe for me....still debating this.
Next summer ill forge the bottom end for long term reliability.

If you dont want that much timing just have Justin pull some out for a mild tune, simple enough to load a tune. Or let him enable the adjustments for the timing on the handheld (if he hasnt already), he can limit it so you can only remove timing so you cant really do any damage.

The car that blew up was running 13psi so there no room for error in the tune, the a/f got really lean up top, that plus some aggressive timing and it hurt something. No way the a/f in the tune would have been set to be that lean (unless there was a mistake in the tune) so most likely there was a fuel delivery issue. Generally you start out very mild and work your way up, not always easy to do with mail order tuning. Not trying to cover for VMP but Justin has a lot of time into these blowers and few problems. Matter of fact I'm really surprised these engines take the abuse as well as they do from any power adder.

its your car, its OK to question and be a little paranoid, I dont want to put a new engine in mine ever lol. But if it breaks I'll fix it and make it better. There are quite a few of VMP tuned TVS cars out there, as far as I know my old '11 is still running well and the older tunes were a little more aggressive than the latest VMP tunes. You are doing the right thing by pulling the plugs and having a look, same with doing a quick compression check.

 

[mebcop]

GREAT info here guys. Thank you!

 

[Snake40]

Sub'd

 

[mebcop]

Updating sct so I can use the Gen 2 data logging. I'll data log a 3rd or 4th gear pull later and post it

 

[mebcop]

How do you read the knock on the sct datalog? It has positive numbers and negative. During my pull it went to positive 2* right off the bat, slowly crept down to 0 by 4,800rpms, and then crept to -2* by 7100rpms.

 

[Fun4me]

How do you read the knock on the sct datalog? It has positive numbers and negative. During my pull it went to positive 2* right off the bat, slowly crept down to 0 by 4,800rpms, and then crept to -2* by 7100rpms.

First your cpu was adding timing and then it was retarding it.

 

[mebcop]

So from 5000rpms to 6200rpms it goes from 0 to pulling 2*, which it maintained pulling 2* until redline. Something I def need to get changed?

 

[Fun4me]

So from 5000rpms to 6200rpms it goes from 0 to pulling 2*, which it maintained pulling 2* until redline. Something I def need to get changed?

Your gas:shrug:

Honestly, I dont know. Sound like a solid question for your tuner.

 

[ArtVandalay16]

No. -(x) equals adding x amount of timing. Positive is pulling x timing. From what I was told, 0 is adding 2.

 

[kevinp]

When you see negative numbers the knock sensors are ADDING timing, its kind of bass akwards, positive numbers is when its retarding. I thought different until I shut off the knock sensors ability to add timing, then you dont see any more negative numbers. Plus on a long pull you can see when the KR log goes positive, the timing goes down.

IMO trusting the knock sensors to add timing is iffy at best when you are tuning close to the edge on a stock engine with FI. I dont even trust them to pull timing really, lot of engines have expired due to people putting too much faith in them. Its a fine line on the knock sensor add and retard rates as well. But for a mild street tune nothing wrong with leaving them add some timing, its usually limited to adding 1-3 degrees anyhow. You can also limit the total overall timing at higher load if you want to make sure it doesnt go over your comfort for advance.

The knock sensors on these are pretty active, when you start seeing 4-5 degrees of retard at high load something is wrong. Unfortunately any noises that are in the knock sensors frequency range will also trigger them, driveline rattle (wheel hop), exhaust rattle, valvetrain noise etc. Even if you see no retard, and even timing added, there still could be enough detonation to damage something. Thats why pulling the plugs and having a look, if you see black peppering on the porcelain from detonation its time to stop and look at why. The knock sensors will seldom save an engine, they are usually a little late to the party but they can give an idea of whats going on at certain RPM ranges.