'88 5-speed dyno log
#33
Captain Obvious
Super User
Super User
You guys with the fine tunning have to be careful. What you are doing is removing all the safety cussion from the programing and if something goes wrong it can be catastrophic. There is no majic in any aftermarket tunning, they all remove the safety factor. Some do more than others and that's where the extra HP comes from. The early 32Vs dodn't have a knock sensor and that why they are more conservative when it comes to their programing. The S4 for have them so the factory reduced the safety margin. Completly removing it, just to get a few more ponnies isn't wise in my books
#34
Burning Brakes
I agree with imooo , chiping is just removing the safety factor . Colin can you post my dyno chart to show Ken what can be done .This is still with a safe tune .
#35
Nordschleife Master
We really need to swap your MAF out Terry, and then re-adjust the tune a little more.
I tuned Terry's car to see zero knocks, and have no ring flutter, put down 352rwhp with cams, headers and exhaust.
I tuned Terry's car to see zero knocks, and have no ring flutter, put down 352rwhp with cams, headers and exhaust.
#36
Inventor
Rennlist Member
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Thread Starter
I usually expect page 3 to be a little more festive - http://www.page3.com/
If you play by the rules, it's nearly impossible to get over 310 rwhp SAE consistently with a S3 manual. (SAE is a beyotch.)
So, I changed the rules.
The little bit of extra on the red line at the top of this thread is just from changing the rules just a little bit.
You can't make the big jump at 3800 rpm, for example, by just upping the advance, because you can't 'get there' with normal tools.
My goal for the S4 is again 310 SAE, but it's also about better response.
Top of the list is making sub-3000 rpm more perky!
If you play by the rules, it's nearly impossible to get over 310 rwhp SAE consistently with a S3 manual. (SAE is a beyotch.)
So, I changed the rules.
The little bit of extra on the red line at the top of this thread is just from changing the rules just a little bit.
You can't make the big jump at 3800 rpm, for example, by just upping the advance, because you can't 'get there' with normal tools.
My goal for the S4 is again 310 SAE, but it's also about better response.
Top of the list is making sub-3000 rpm more perky!
#37
You have to be in this with the understanding that the intake simply sucks. Seriously. No one wishes to admit it, but its restrictive for flow. You can suggest that its not restrictive at this power level.
#41
Inventor
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Thread Starter
I reckon there is another 20 rwhp waiting to be unlocked.
That wasn't the point of this dyno, though. I wanted to get a working 24# chip.
According to the MAF voltage logs, the S4 is flowing as well, or better than the S3 at peak HP.
Like the S3, fueling past 5600 rpm s*cks, and it is not tuneable with the stock RPM/MAF table divisions. (EG. jumps from 5600 to 6200.)
The ignition timing will need recoding too, if I hope to do what I did with the S3 (dark red).
EZ tuning will easily fill in the valleys somewhat.
The dark blue line is my experimental EZ tune (010). Red is the LH only tune (006).
3600-3800 is already filling in. Around 4800, though, the timing is off, but I haven't worked my up there, yet.
Just with the LH chip, I was able to get rid of the characteristic S4 'glitch' at ~3650.
I've seen it on other S4 dyno graphs. You can feel it driving as a sudden power increase around 4000, kinda of like turbo lag.
I recoded the flappy to always be open, closing only for the first torque peak between ~2500 and ~3600.
Stock flappy operation is green (002) and light blue (008). Red (006) and dark blue (010), modified flappy.
Right now, except for around 3650, there is no power increase, or decrease, but it is much smoother, and no 'thump' at 4000.
I hope it will allow for higher numbers later, with (much) more fuel and ignition tuning/coding.
All these runs were very consistent. I did at least two of each change, and they all overlayed each other.
I unplugged the radiator sensor, keeping the fans on full all the time. Cooling down for a few minutes between changes.
That wasn't the point of this dyno, though. I wanted to get a working 24# chip.
According to the MAF voltage logs, the S4 is flowing as well, or better than the S3 at peak HP.
Like the S3, fueling past 5600 rpm s*cks, and it is not tuneable with the stock RPM/MAF table divisions. (EG. jumps from 5600 to 6200.)
The ignition timing will need recoding too, if I hope to do what I did with the S3 (dark red).
EZ tuning will easily fill in the valleys somewhat.
The dark blue line is my experimental EZ tune (010). Red is the LH only tune (006).
3600-3800 is already filling in. Around 4800, though, the timing is off, but I haven't worked my up there, yet.
Just with the LH chip, I was able to get rid of the characteristic S4 'glitch' at ~3650.
I've seen it on other S4 dyno graphs. You can feel it driving as a sudden power increase around 4000, kinda of like turbo lag.
I recoded the flappy to always be open, closing only for the first torque peak between ~2500 and ~3600.
Stock flappy operation is green (002) and light blue (008). Red (006) and dark blue (010), modified flappy.
Right now, except for around 3650, there is no power increase, or decrease, but it is much smoother, and no 'thump' at 4000.
I hope it will allow for higher numbers later, with (much) more fuel and ignition tuning/coding.
All these runs were very consistent. I did at least two of each change, and they all overlayed each other.
I unplugged the radiator sensor, keeping the fans on full all the time. Cooling down for a few minutes between changes.
#42
Inventor
Rennlist Member
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Side note - I can't believe 19# injectors were spec'ed all the way up to GTS.
Could only have been for low rpm emissions.
Even the 24# are hitting 90% duty past 5000 rpm at 12.5 AFR, with half injector rate disabled.
I thought about going to 30#, but I'm going to see if the LH2.3 half rate can be tuned properly.
(Half rate starts at ~5100, stock. I'll probably push that a little higher.)
With the S3, half rate isn't needed with their stock 24# and a S4 FPR. (S3s just can't breathe enough over 5200 rpm.)
Plus, I dumped the half rate code for space for my own.
Could only have been for low rpm emissions.
Even the 24# are hitting 90% duty past 5000 rpm at 12.5 AFR, with half injector rate disabled.
I thought about going to 30#, but I'm going to see if the LH2.3 half rate can be tuned properly.
(Half rate starts at ~5100, stock. I'll probably push that a little higher.)
With the S3, half rate isn't needed with their stock 24# and a S4 FPR. (S3s just can't breathe enough over 5200 rpm.)
Plus, I dumped the half rate code for space for my own.
#43
Official Bay Area Patriot
Fuse 24 Assassin
Rennlist Member
Fuse 24 Assassin
Rennlist Member
You guys with the fine tunning have to be careful. What you are doing is removing all the safety cussion from the programing and if something goes wrong it can be catastrophic. There is no majic in any aftermarket tunning, they all remove the safety factor. Some do more than others and that's where the extra HP comes from. The early 32Vs dodn't have a knock sensor and that why they are more conservative when it comes to their programing. The S4 for have them so the factory reduced the safety margin. Completly removing it, just to get a few more ponnies isn't wise in my books
Happened to me with a 944 chip a while back that cost me a motor and broken piston rings. Car was detonating and pinging in the upper RPMs. After my catastrophic experience, I will never chip again. All engines are different based on mileage, wear and tear, and use.
#45
Inventor
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Thread Starter
That's the comparison S3 graph. Dyno glitch.
If you get a bunch of those, or they happen regularly in the same spot, I would start backing off the timing...
If you get a bunch of those, or they happen regularly in the same spot, I would start backing off the timing...