Dyno Run

ChrisM

Well-known user
Apr 12, 2007
198
0
Berkshire
My friend was putting his Focus ST on the rolling road this afternoon, thought I would take my cougar along to see how many horses have escaped from its 9 year old engine. I was pleasantly surprised:

Dynorun.jpg


179 BHP, I think that an extra BHP for every year old it is. Next year I could have 180???

Only mods are an st200 airbox and with K&N panel filter. ItÔÇÖs got magncor HT leads, but donÔÇÖt think that would make any difference.

Recently I was thinking of getting st200 UIM, LIM and throttle body, but most people with those mods rarely get over 190 BHP with my setup, so now personally I think they are really not worth the expense for the extra horses.

I think I'm better spending my money on an exhaust system, will make it sound better as well.
 
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Very good, you can really see where the secondaries kick in, i wander if there is a way of adjusting the rpm point at which they open?
 
If you did it would probably just move the flat spot. To decrease the duration of the flat spot, clean and lube the IMRC


... and the opening point is mapped to rpm and load, not just one fixed rpm. Probably one of those occassions when it's sensible to trust those who set the engine up on the dyno in the first place - unless you have access to a dyno and some time to spare of course :smile5:

Good result though Chris, must be pleased with that :)
 
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thats a surprise think might get mine done this year at fordfair as i have kand n and exhaust and few other bits but as a result for a 9 year old car proves its been looked after like james may done to a renault polished and ported inlets gained 33bhp on top gear
 
My friend was putting his Focus ST on the rolling road this afternoon, thought I would take my cougar along to see how many horses have escaped from its 9 year old engine. I was pleasantly surprised:

Dynorun.jpg


179 BHP, I think that an extra BHP for every year old it is. Next year I could have 180???

Only mods are an st200 airbox and with K&N panel filter. ItÔÇÖs got magncor HT leads, but donÔÇÖt think that would make any difference.

Recently I was thinking of getting st200 UIM, LIM and throttle body, but most people with those mods rarely get over 190 BHP with my setup, so now personally I think they are really not worth the expense for the extra horses.

I think I'm better spending my money on an exhaust system, will make it sound better as well.

That sounds brilliant - always thought engines lost power with years?? Would be intrigued to know what your engine was pushing out in standard form? As I know there are different reports (depending upon what your reading) that state the Cougar V6 can be anything from 167bhp to 180bhp in standard form. (y)
 
Yeh Jamie I'm pleased, was asked before the run what figure I was expecting, I said if I get 160 I'd happy.

Although the engine is coming up for 9 years old, itÔÇÖs only done 55,500 miles. It's really not that long broken in. Keeping it properly serviced it should last me quite a number of years. I got the car two years ago when it only had 38,000 miles so now I know itÔÇÖs not been abused before I got it.

On the rolling road the rev's are raised really slowly, and if the rpm point when secondaryÔÇÖs open changes depending on the engine load IÔÇÖd imagine the printout shows the latest point when they would open, as the load would be minimum on the rolling road.

When the engine is trying to pull a ton weight going from 50 to 70mph, the load would be a lot more and I'd imagine the secondaryÔÇÖs open up at 3000rpm instead of 3500rpm making the torque curve a lot flatter. There wouldn't be that big drop in torque curve.

This is probably the reason you feel the secondaryÔÇÖs open in first in second gear, but less in 4th and 5th, because in the lower gears the secondaires open later, (similar to graph above).
 
Secondaries open at the same RPM it just depends on how hard your foot is planted that affects the computers decision to open them.
The only reason you feel it later in the lower gears is because the engine is spinning up quicker than it would in the higher ones, and you feel less pull in the higher gears as its got more weight to pull, bhp stays same but is geared higher so you feel it less
 
To plot a torque curve, and thus calculate power at any given RPM, the test will normally be done at full throttle throughout, using the brakes on the dynomometer/rolling road to restrict the rpm.

Without full throttle throughout, the torque curve (and thus power) will be less than maximum for any given rpm (y)

That's where the term 'Brake Horse Power' comes from - it's a test with the engine at full throttle and being stopped from revving freely by the dyno brakes. By knowing how much torque the brakes are applying to control the engine rpm, the torque produced by the engine must equal this and that then allows the power to be calculated. Nowadays it's done with a torque converter or an electric motor used to resist the engine, but it used to be a brake on the flywheel (y)
 
Interesting, I just thought the tester had a very steady foot to rise the rpm slowly. I've stood on the rollers a felt how loosely the would spin, I take it thats when brake isn't applied. I'm assuming when they start the run and the machine says 'teach me @ 3000rpm' thats when touque converter is getting setup with the correct settings.

Took about 5 secs to rise the rpm around each 1000, so watching the graph draw the estimated bhp you can really see when the secondaries open, on the first run my friend looked over at me when rpm was about 3000 and the bhp line was lowering, with a look of worry, thinking there was problem, then the secondaires opened and the graph shoot right up climbing and climbing. Was a good feeling seeing that happen.

The graph I was watching get drawn bears no resemblance to the finial one, cause I hadden't taken into account drag and loss from drive train.