I was comparing the UNICHIP Dyno plots that Randy at Webbmotorsports published with cars at various stages of tune comparing the before and after of the UNICHIP ECU. I found the results very interesting. Not evaluating the UNICHIP but evaluating what results you get from what mods. It really tells you what you are getting for your money and maybe even when you should stop modding. Here are the results using a very accurate ( ) piece of paper on my flat panel screen to crossreference the results. Top numbers for each group are with the UNICHIP ECU, bottom was the base run. All numbers are Torque values.

3k RPM 4.5k RPM 6k RMP

Intake Only
140 158 158
130 148 144
Intake and Exhaust
152 167 170
142 157 153
Pulley, Intake and Exhaust
165 180 179
155 178 172
Maxed out Pulley,Head,Cam,Header,IC, Intake, Exhaust, throttle body etc...
162 180 185
148 174 172

All those mods on the Maxed out Run compared to the Pulley, Intake and exhaust really tells me something. All of the high dollar parts, header, ported head w/cam, throttle body and you loose bottom end torque and only see the benifits from 6k RPM to 7K RPM. If you look at the graph all those mods just keep that last 1k RPM from falling off as much. This really makes me think I'd be better off spending my money on a big intercooler and the 19% pulley and I'll have alot more torque below 6k RPM making my "Butt Dyno" and my wallet very happy!

Edited Note : Either way I think the ECU upgrade is a good idea. The Pulley and ECU still provides a big torque boost at lower than 3k and above 6k. The ECU mod will make the most out of the mods you have.

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I wouldn't put much, if any, stock in those numbers, relative or otherwise. They are using a completely bogus coast-down method to try to derive crank hp from wheel hp numbers. Until I see the same results on a normal chassis dyno, I won't believe any of them.

 

>>I wouldn't put much, if any, stock in those numbers, relative or otherwise. They are using a completely bogus coast-down method to try to derive crank hp from wheel hp numbers. Until I see the same results on a normal chassis dyno, I won't believe any of them.

I would have thought on the same Dyno, using the same methods that they would have been comparable. It's still what I would have expected. Headers, Head Porting, Throttle bodies just provide more air at the point at which those items become restrictive which occurs at higher RPM's. I think it's a good Velocity vs Volume comparison for our air pumps.

 

The problem is that Randy's numbers aren't comparing anything that has actually been measured. They are applying a ficticious drivetrain loss calculation that skews all of the results, and not in a predictable manner. "bhp" numbers gathered from anything other than an engine dyno are worth the paper that they are printed on.

 

my rig, through it's various incarnations, has dynoed:
128ft-lbs(stock) up to the present 174ft-lbs, and it is now way modded out.

measured at the wheels, sometimes on a Mustang, sometimes on a Dynojet, with comparison readings validating dyno to dyno changes. (last run on the Mustang very close to next run on Dynojet)

 

This months Hotrod magazine has a very good article comparing the different chassis style dyno's. They found very different results when the same car is tested on different brand dynos or even the same brand but with different operators. In one case they recorded a 10hp difference between two runs by changing the tiedowns by 1 click. As the transmission oil warmed up friction went down and affected the results. The smaller/lighter the car the more variance was shown as most dynos are designed around an "average" car weighing 3400lbs. Different tires also had an effect on the results. For chassis dynos they recommended only using the change is output for each mod as a guide for tuning and not the actual numbers. The load sensing type was concidered the most accurate as it took into account the vehicle weight and drivetrain. All the different styles have their pluses and minus'. Check it out.
Dan

 

THIS IS WHAT I'VE BEEN SAYING!!!!

On the other hand, Like Andy said, I'm far from sold on these numbers. For one, they are extremely inflated. Two, all other ECUs seem to make the MOST power on a pullied car. Now for some reason with the Unichip, the intake, exhaust, and pulley combo makes the LEAST gains. Something isn't right here....

And as for the intake, exhaust, and pulley combo...the gains are really mediocre at least. There's hardly any torque gain between 3.5k-5.5k and that's where I spend most of my time!!! The curve is awful...the PEAK torque might be decent but it's really just in a very narrow RPM range that there are gains.

Time will tell....

 

greatgro,

Yes, I'm certainly not sold on these number either, these are just the first numbers that I have been able to compare a modded MINI at different stages of tune and really show that many of the expensive mods provide very little low/mid torque (and may even reduce low/mid torque) and for a street/Autox occasional track car they add up to very little value. I just don't see alot of need for high RPM parts unless I'm running my MINI around an oval in NASCAR. It makes all the difference in the world being able to pull out of a corner in second gear at 4k RPM instead of at 6K in first gear. At my local road course those who were driving Miata's or MCS's without the pulley had to be in first gear banging the rev limiter out of the corner and I could stay in 2nd an still had to be careful to squeeze the throttle in some corners. But more low/mid torque and an LSD and this car would be awsome out of the corners. I think I'll save my money for an LSD and not a new head.

I also think that the reason you see such short gains with the ECU and the pulley is that the pulley has already taken a large chunk out gains you get from leaning the A/F ratio. I also think that's why other have reported such noticable gains from the 19%. Again it leans out the A/F ratio further and with the 19% and an ECU I bet the gains would be even much smaller.

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The Magnaflow exhaust is a good example of a mod with useful gains only above 6k:



Yet, it's still much louder than stock at low rpm and light loads. Hmm ....