RKD in OKC

Tell Dave you need to post the Dyno with the Autothority Chips, remapped Autothority Chips and Your chips.

rberry951

Yes Brian, that's my site. Same car, same gas in the tank even. The difference was on the first two charts at 15.5psi and 20psi the car had a old wastegate that would not hold boost and a 3" exhaust. The new 16psi run was with a dual port wastegate and 4" exhaust.

rberry951

Great points, I'm glad you mention this. This is something I keep telling my customers over and over. There's nothing 'magic' about the chips, I have not unlocked some secret code to get more power. And they keep asking why the chips make so much of a difference in their cars. I tell them all the same thing, I make the difference. These motronic computers are toys to me. As I've stated before the full motronic code is about ONE printed sheet of paper in size, that's it. All the BS tricks and gimmicks in the code is just that, BS. The results you are seeing are a direct result of my tuning abilities, no hype, no BS, just the best I can do.

And the thing is I don't tune for peak numbers, my tuning goals are quicker spool, broader power band, and drivability. The first thing people notice about the chips is driving around is pleasurable. Higher peak numbers are just a side effect of good overall performance.

toddk911

A k26/8 should be able to make and hold 15-16psi.

SoloRacer

I have friend with a k27/8 on his car and his chips are all wrong. I went through the chip selector on the website and have a question. What is the difference between the two boost options (ie: 14-17 and 17-21)? Wouldn't the chips with the higher boost maps work for the lower boost settings too? Why have two different chips? Different fuel? Since this turbo is new to him I don't know what "boost" he will be running. It's a full on race car and I imagine he will run higher octane fuel.

toddk911

Volume difference of 2.5" vs. 4" cat back.

Assuming you take the pipe section from just before where the cat would be to the muffler, that would be about 6 feet total length maybe?

Area circle: 2.5" circumference = 3.14 x 1.25 squared = 4.91 sq. inches

4" = 3.14 x 2 squared = 12.56 square inches

Take that area to use for volume of cylinder:

V=h(length of pipe in this case) x base area:

Volume of 2.5" = 6 x 4.91 = 29.46 cubic inches

4" = 6 x 12.56 = 75.36 cubic inches.

So, that 4" cat back section, roughly, flows more/has more capicity to flow more than double the volume of a stock 2.5" cat back section.

How much difference would that make???

rberry951

The chip selector is used to gain more info about the car, when people order I ask for additional info on the car, especially a different turbo. The chip selector boost ranges are 12-14 for conservative boost, a little less fuel on the upper ranges under boost but still enough to run good A/F if they want to go up to 18. 15-18 is the most common, and what give people the ability to run 15-21psi as Toddk911 does with A/F varying no more than .2 across the board. 19-25 range is for nuts like me who want to try to blow something up. The differences in boost don't equate to huge differences in the mappings. Turbo size, injector size, and combinations of things make bigger differences in the maps. The ability to run higher boost than your stated goal is built in for protection, but that doesn't mean dumping in more fuel across the board, it means adding fuel or pulling back timing where it needs to be in the part of the curve where that particular turbo/injector/exhaust/boost combination needs it. I try to be as specific as possible. A lot more work for me, but a lot better product in the long run.

Regards,
Russell

hosrom_951

Good job Russell

Chris White

Impressive numbers Russell – I don’t want to sound too skeptical but can you give us an idea where the significant improvements have been made to the tuning? Getting the A/f Ratio right has been done before but not with such good results.
I am not looking for the company secrets – just an idea where you are making such gains.

rberry951

Thanks Chris! No secrets to reveal, on my car I began a lengthy trial and error process of looking at as much info as I could get my hands on, especially dyno print outs. Then started asking myself questions. Why is the power curve of the engine the way it is? Well, it's just an air pump, and these are the characteristics of it. So how much room do I have to change those characteristics? And I found that there is actually quite a bit of room to manipulate timing and fuel within reasonable ranges to change those characteristics such as A/F, power curve, etc. Then looked at differences in power curves of different sized turbos and how they change the overall volume/pressure of air flowing. It all led me to a really nice combination of variables I can tune to achieve a really nice running car.

Another example, I just started working on the 944S chip. In the very first stab at it I wished to accomplish addressing the complaints people tell me about the car in stock form, using only their seat-o-meter. I don't have a 944S, so rely solely on what I hear from others. The biggest complaints were bad idle, no low end torque, jerky top end performance, and shakey (shudder) when they lift. I get a stock chip, read it, look at the differences of the new variables of the 16V head makes, and started making changes. The guy reported back that the bottom end was full of torque, acceleration was smooth across the board, and the shudder is gone. He takes it to the dyno, the curves are cleaner/smoother than stock, as expected. And it made 4 more HP than stock chips just as a side effect of better running and a slightly broader power curve. From that dyno I made another chip with very slight changes to see how far I it goes in either direction at various points and what effects it will have. He went back to the dyno, HP increase from stock was the same, TQ curve a little better, but there were some dead spots. That gave me the info I needed to make the next chip I sent him to dyno which has some pretty aggressive changes based on the first two tests. I didn't touch the partial throttle maps because they seem to be performing exactly as desired, but brought the WOT maps in line with the numbers in the partial. We'll see the results of that next week. And if it takes one more stab at it to get it right where I want it, then so be it.

But that's the secret in a nutshell, tuning and more tuning until I get as much performance out of the engine I can. And not all tuning is done on a dyno. A dyno can only simulate real world conditions, I find it better to tune to the real world conditions, especially on the turbo cars by using data logs under various conditions. It gives me better info to work with than dynos do.

Regards,
Russell

Brian Morris

There is no way that dyno sheet is at 16 psi. The previous dyno sheets on the same car on the same dyno show that dyno run was done at 20 psi.

In the following link Dave Lindsey did a 15.5 psi and 20 psi runs. The car is stock except for chips, no cat and a 3" Lindsey exhaust. The boost was "falling to 12 psi".

Here's the link: http://forums.maxhpkit.com/viewtopic...78ecec0e8da0ec

Here's the 15.5 psi run - pretty much what you'd expect, but with some boost falling off. This is totally consistent with these cars being dyno'd hundreds of times.




Here's a dyno sheet of another k26/8 at 16 psi w/ "well known" chips - almost identical result:




Here's the dyno of Dave Lindseys car at 20 psi with "falling boost". Notice the torque - 339.3




In this thread:
http://www.turbo944.com/bbs/config.c...ames;read=3942
Dave Lindsey went back to the dyno after adding their dual port wastegate, and still with the *3* exhaust. He claims the first run was done at *16* psi, but now the torque has to 340 - basically identical to the former 20 psi run. The wastegate has *no* effect on this. It was either hitting max boost before or it wasn't. He says that the boost is now falling to "around 13" which makes sense, since he's picked up about 15 HP over the previous 20 psi dyno.

Here's the dyno - the blue line is the 3" exhaust, the red line is 4" all at "16" psi.



He goes on to explain how he picked up 5 tq and 15 hp with the 4" exhaust. This doesn't explain the *40* lb/ft of torque that was "magically" gained. No other car with that turbo has had that kind of torque at 16 psi. And it's not the tuning - spare me.

Here's the last dyno by itself:




It does look like they picked up a little power with the 4" but the run was clearly done at 20 psi. The torque curve doesn't magically jump betwee two 16 psi runs by almost 40 ft/lbs of torque - one was at 16 psi and the second was at 20 psi.

This was all with the same car on the same dyno with the same chips. The only changes were the wastegate, exhaust and ... the boost level.

As Duke said "tuning" doesn't get you changes like this if the chips were OK in the first case. In this case it's actually the same chips. The chips seem fine - just like ones that have been available for years and years. Just being sold by some guy for cheap - great. Leave it that.

--Brian Morris
89 951

rberry951

Wow Brian, thanks for reposting everything that has ever been posted. What do you want for proof? Next run Dave is going to video it, do you want to hop over to the dyno shop and be there yourself when he does it? I know the truth, obviously you do not. I'm sure your opinion is based on a lot of experience in the area, but it's just that, your opinion. I don't see where you need to take the route you're taking and call me, Dave, and they dyno shop all liars. Being skeptical is fine, don't mind it a bit, and we'll just keep bringing forth numbers that will eventually lay the skeptics to rest.

Regards,
Russell

Bri Bro

Russell, just ask for a local rennlist guy to observe, I bet you will have a LOT of volunteers.

rberry951

Actually that's a good idea, I'm sure there are several in Dave's area. I happen to be 1000 miles from there, so I can't even attend

Pauerman

Now that things have cooled off here in AZ, very soon I'll be hitting the dyno with these chips in an '89 951. It's got the k26/8 still and it's modded with a Turbonetics EVO WG, full SFR exhaust and a Turbonetics MBC in single port mode. The car will be tested on a Dynapack dyno and I will be videoing the session to authenticate the results.