Rolling Road

[Psycho man]

Ignorance is not bliss.

I’ve heard the expression rolling road test.

What’s it all about, when do you use it, is it any use, what does it cost, is it worth it?

X/flow

 

 

 

[Tony Martyr]

The term 'rolling road' is a generic term covering a range of devices more correctly described as chassis dynamometers. They enable you to drive a car over its full speed and power range while stationary which helps instumentation and the logistics of adjustment. Such devices also measure the torque resisting that generated by the vehicle wheels as well as the rotational speed.

To enable the control map of a modern engine to be tuned it is necessary to carry out tests at a full range of engine (vehicle) states, which a rolling road allows.

The states needing to run are:

Cold start,

Warm up routine under power

Full power curve

Part throttle curve

Overrun warm etc.

In addition to the power measurements you have to monitor and adjust the lambda values. air/fuel ratio etc.

Not only is it worthwhile it is essential if you have modified your engine, albeit you may never get it as refined as the original map that has taken 100s of hours to optimize.

How much it costs depends on how much adjustment is required

[James Arnold]

I have just had my 1700 xflow rolling roaded. All a little bit more basic than Tony I'm afraid. I suspect that its partly as a result of having a dizzy and webbers. My operator did some basic checks, including a change to the timing and then did a run up through the rev range. Announced all looked good except running rich at the top end. Some new, err, somethings, in my webbers and all was better. Net result 100 bhp indicated at the rear wheels became 115. All for 75 quid. That must be the cheapest horse power I ever bought and the many stories of years in the business thrown in for free. I didn't know there was so much TR7 history to hear....

I suspect that you want to select the right rolling road for the type of car you have. My chappy has been doing xflows for 20 years. I phoned a more local place who didn't sound like they knew one end of a webber from another, even by my standards! No doubt they could work wonders with a black box...

Its also a fun way to spend an hour.

J

[fast_cat]

James,

 

If you don't mind me asking where is this rolling road ? I have a modified 1700 X-flow with twin 40's which needs a tune...

 

Rob

[Eugene]

The best bet for X-Flow rolling road setup is Roger King (www.rogerkingengines.com). He has more experience than anyone.

 

Small Boy - with Big Toy!

[James Arnold]

I went to Red Line Tuning who are in Iver Bucks(tel 01753 655522).

Its run by Tony who many years ago tuned a race mini for me.

I wanted what you might call a cost effective solution (ie cheap) and was not too fussed about getting the final few percent of power. If, like me, you have an engine of dubious pedigree and want to get the most from it and get an experienced opinion, I would recommmend him.

If you want that final horse power to beat off the competition on the grid I really can't say if he is your man. Likewise I don't feel I can comment on how his service might compare to Mr King's.

James

[Psycho man]

How critical is the fuel one is using when going for a R/R set up. With a cross flow one may be using 4 star every 4 tanks, and what about those times when you can't find super unleaded! Doesn't this ruin all the set up?