Articles tagged with: DIY

Intake comparison on 4AGE 20V BlackTop

on Tuesday, 07 February 2012. Posted in Using PerfExpert

Performances difference between the original plenum and open velocity stacks

Here's a little comparison that has been done on Stephane's Toyota AE82 Twin Cam GT : seeing with PerfExpert the difference in torque and power between the original plenum (without the air filter) and open velocity stacks.

To perform reliably this test it was necessary to proceed as following :
- Always launch the car from the same mark on the road
- Always WOT at the same mark on the road
- Take measurements at the same direction of travel
- Be sure to follow the PerfExpert basic measurement procedures (phone calibration performed, impeccable phone fixation, little wind, free road, lift windows...)
- If the car remained parked in a while then drive a few minutes at medium speed to cool the engine bay in order to always make the measurements under similar engine bay temperature conditions 
- For each setup (plenum or open stacks), perform at least two measurements having less than 2% deviation to confirm their reliability. Indeed non-repeatable measurements (differences of more than 2%) reflect a poor phone fixation or poor conditions (road, wind...).


Toyota Corolla AE82 Twin Cam GT


At first, measurements with T3 open stacks

Toyota 4AGE 20V blacktop open stacks

PerfExpert 4AGE 20 blacktop cornets 1

PerfExpert 4AGE 20 blacktop cornets 2


Here are the results with this setup :
- 159.6hp at 7300rpm et 131.8Ft.Lb at 5500rpm
- 159.1hp at 7300rpm et 133.2Ft.Lb at 5300rpm



Lets see now the results with the OEM plenum and OEM stacks. Unfortunately we didn't have a cold air feed to the plenum for the tests. And note that the curved OEM stacks had been cut by the previous car owner...


4AGE 20V blacktop plenum 14AGE 20V blacktop plenum

PerfExpert 4AGE 20V blacktop plenum 1

PerfExpert 4AGE 20V blacktop plenum 2


Here are the results with this setup :
- 150.4hp at 7200rpm et 128.2Ft.Lb at 5200rpm
- 151.3hp at 7200rpm et 130.4Ft.Lb at 5200rpm

This shows a clear advantage of open stacks in power (more than 5%), and a slight advantage in Torque. But the most interesting is to see the curves comparison. Here is a Google Doc with an overlay made ​​from a fusion of data exports made ​​from the application :

Toyota 4AGE 20v blacktop : open stacks VS plenum

Not enough room for the legend so I'll give more details here :
- P1 & P2 are the 2 power curves in open stacks setup
- T1 & T2 are the 2 torque curves in open stacks setup
- P3 & P4 are the 2 power curves in plenum setup
- T3 & T4 are the 2 torque curves in plenum setup

Note that with the plenum there is a little more torque before 4000rpm and less torque after. So really, even if the open stacks give more torque maximum value, the plenum give a more torquey engine at low rpm.
A pity that we didn't have a 100% stock plenum (whose stacks are not cut) and the original airbox + filter. The comparison would have been even more interesting.

Introducing Dyno Tests Comparison

on Friday, 09 January 2015. Posted in Using PerfExpert

Make comparisons of your test results using the PerfExpert Analysis Tool

Introducing Dyno Tests Comparison

You requested it and it's finally there : you can now see several dyno test results overlaid on the same graph. This is very useful when you want to find which of your car's setups produce best performance, as we seen on the Corolla AE82 20V intakes comparison and the Mercedes 190E Turbo sizes comparison. This is possible thanks to our new Analysis Tool by using your mobile or desktop internet browser. This tool is available only for results that are online on the PerfExpert Network.

To compare your results :

1 - Log in to the PerfExpert Network and go to 'My PerfExpert'

If you don't have a PerfExpert Network account, you have to register by using our mobile Dyno & Timed Run app : go to 'Account' in the Test screen menu and follow instructions.

2 - Open the desired car to see its test results

Here, you will only see results that have been uploaded from the mobile app, either by clicking on 'Open web link' on the Result screen of the the mobile app or by sharing via the 'Web' method.


3 - Select the results you want to compare and click the 'Compare' button that appears at the bottom-right of the screen

You can select up to 3 results for comparison. For now, only dyno test results with the same units are comparable.

Results - selection 

4 - See results comparison at each point of the curves


If you have questions or feedbacks, feel free to contact us.


DIY phone mount

on Friday, 25 April 2014. Posted in Using PerfExpert

How to perform consistent measurements easily using the cheapest phone mount solution

DIY phone mount

To perform consistent, accurate and reliable Dyno and Timed Run tests with PerfExpert, you must ensure that all the measurement conditions are met.

One of these conditions is that the phone must be one with the car during the test : its sensors must perfectly "feel" the car's movements, and no other parasite movement or vibration. So you must pay close attention to the phone mount you use, and check that the phone position reach the PerfExpert mounting requirements. In the dyno test video tutorial, the phone is secured by a very strong windshield mount, equipped with a large suction cup and a very short, solid arm.

There is a much cheaper way to have your phone correctly secured in your car, and that allow you to immediatly perform tests : using the original box of your phone, the passenger seat, and a heavy book!

Remove the cover of your phone's box and all unnecessary packaging

DIY Phone mount 1DIY Phone mount 2DIY Phone mount 3DIY Phone mount 4DIY Phone mount 5

Put the phone inside the box and shake it sideways to check if the phone can move

DIY Phone mount 6DIY Phone mount 7

Prevent any phone movement by wedging it inside the box

DIY Phone mount 8DIY Phone mount 9DIY Phone mount 10

Make the power button accessible if needed

DIY Phone mount 11DIY Phone mount 12

Put the box on the passenger seat, and wedge it against its backrest

DIY Phone mount 13

If needed, you can stall the box with heavy objects located on its sides and/or in front of it

DIY Phone mount 14

Ok! You're ready to test your car!