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Dyno Dilemma

DamnImStoked

DamnImStoked

Messages
18
Hi guys. If anyone could shine some light on this it would be greatly appreciated.

Taken my ep3 for its first ever dyno run today, and had a rather harsh wake up call. My car seems to be lacking a substantial amount of power compared to a lot of the guys who were running almost identical modifications, and even more surprisingly less than a bone stock one.

Car is a 52 plate, and covered nearly 75k, full history and serviced regularly. Plugs were swapped out for iridiums about 6 months ago, and the timing chain has been done in the previous owners care. Only modifications that should affect power output slightly are Tegiwa induction kit and a 2.5 catback exhaust. After it's dyno run the best it managed was 187hp. 3 friends running almost identical mods hit 198 to 200 and a guy who came with a completely standard car managed the factory 197. If it helps all the other 4 cars are past the 110k mark so I need to find out where I'm going wrong.

I seem to have reduced my cars power, as opposed to increasing it. I didn't expect to be making any records but surely improving the breathing should have helped. The other thing that confuses me, is when me and any of my friends have had a play on private roads I seem to pull away from them all slowly. Genuinely can't seem get my head around it.

If anyone can pass on something I might be missing it would be greatly appreciated.

Thanks in advance.
 
Tom83, no you're correct there is no map. However the 3 people running the same/similar mods didn't either. Feel like I'm missing something completely.
 
Or more interestingly, it could be running a map that you don't know it has, for other mods.

Have you looked at the ECU, is it standard?
 
I haven't actually looked at the ecu itself but I'm only the second owner. Previous owner was shall we say an older woman, and everything was original. Plus if it was mapped then isn't the crossover point set lower than standard normally
 
If it drives and feels good on the road i wouldn't worry, it's only a number at the end of the day.
I'm certainly no expert and maybe someone can clarify but would different tyres and tread depths make a difference to readings?
 
This is where things get complicated. It drives fine, after the dyno runs yesterday we went for a drive out again. The other ep3s that all pulled substantially more power than mine are slower than mine on a rolling start. By quite a noticeable gap as well. With regards to the exhaust Chris it was new about 12 months ago, and the cat was replaced at the same time due to the flange being rotten. It doesn't make any sense to me at all how cars with the same mods and nearly double the mileage make more power than mine, yet fall behind on a straight run.
 
Was it lower than expected output just at the top end, or throughout the entire rev range? Seeing a dyno chart would help.
What did you dyno operator have to say about it?
Is your car stipped out? Lower sidewall tyres? These little things can add up.
 
Flashy yeah my car is stripped but so are two of the others I had a drive out with. As for tyres I'm running AD08R all round but not sure how that would affect a rolling start from 40. As for driver ability I'm no expert and been driving less than the others.

Smeghead I'm assuming throughout, not 100% though. I didnt get chance speak to the dyno guys too much with it being a group organised thing and them having 20 motors to dyno. Torque was 122, all the others were 135 and upwards. As said the car is stripped but so we're 2 others. Tyre wise I know 1 person is definitely running the exact same size as me, the others I'm not so sure of.

Just want to get my car making at least the power it came with as standard. Anything over would be a bonus considering iv already spent quite a bit on it for mods.
 
How many pulls on the dyno did it do? Due to volume of people there I'm guessing they did some gentle warm up runs then a single pull power run.
I'd suspect at this point that the dyno operator somehow goosed up the run (and there are a surprisingly number of variables to get wrong especially if they're fiddling about with it between each car), which has resulted in an artificially low reading.
Or, none of your mates can drive properly.

I'd be tempted to get it on a different dyno to confirm the result. If it again shows low for what's expected for that car\mods on that dyno - which is important, as I'm sure you know you can't really directly compare between two different dynos - then you have a confirmed problem. If it shows as good, happy days.
Could even be worth taking it back to the same place if it's local to you and most convenient to confirm the result. That would be more directly comparable to the last one run, though the problem I'd have with that is even at busy club etc dyno days, a good dyno operator should and usually do briefly feed back to owners about unusual results or issues they notice.
Where was it done?
 
Did your friends use the same dyno that you have as well? Servicing all up to date too? Fuel filter etc (I know you mentioned plugs).
 
You say the cat was replaced, what with? A new Honda cat is a huge amount of money to spend on a car of the EP3's age (like half the purchase price of the car). If it's a second-hand one then it'd be good to know how many miles the donor car had gone through too.
 
Smeghead. I warmed it up before it went on myself and it had 3 runs, 187 being the highest. Fortunately it was a local company so I'm thinking of trying a timing chain and getting clearances reset. ** take it to a few dynos near to me afterwards but i doubt it will amount to the 10hp I'm missing.

Krzys Yeah we all used the same dyno on the day as it was a local car club who organised it for us. Yeah servicing is more than up to date, oil gets changed every 4k. As for fuel filter that may be an option as they're in tank on EPs.

Mike.H yes you're correct, price of a genuine cat was ridiculous. I didn't want to buy a 2nd hand one for the reason you mentioned as chances were it would be the same condition if not worse. Due to this I purchased a high flow sports cat. Unless of course the standard cats are exceptionally high flowing I can't see this being my problem but I appreciate the suggestion all the same.
 
Personally if the car is running fine for you when you drive it & performs well against similar cars, I wouldn't lose any sleep over it.
There are many variables on your particular car that could be at work here - over-sensitive knock sensor, engine heatsoak due to less that ideal cooling system performance or cooling fan\intake\bonnet layout disrupting airflow to the intake, throttle cable adjustment\stiffness\carpet under the pedal not allowing full pedal travel unless you mash it properly, and so on.
A lot of these may not be apparent as a dyno run is harder on a car than driving on the road, and some may only manifest themselves on the dyno or with a different driver. Or the opposite can also be true; a chap on here recently had an intermittent running issue that didn't occur on the dyno, from what he described it was a chaffed IAT wire causing the problem, the fans on the dyno were pushing the wire away from the car, therefore 'fixing' the short and it ran perfectly :)

Without looking at the mechanical stuff in the bay, seeing a dyno graph or looking at the running parameters of the car it's going to be very difficult to troubleshoot it. I certainly wouldn't go buying any parts for it just yet.

I'd suggest getting it tuned for your mods in a dedicated dyno session, and have the tuner check the basic adjustments and view the important parameters whilst it's running. Any major issues will be obvious to them. Get a compression\leak down test if you like, and as you say check the other stuff like timing.
Don't fall into the trap of playing dyno top trumps with other people!

If I had to take a guess at mechanical fault I'd say plugs too. Maybe a misfire at very high revs\load and not obvious on the road. Comparatively cheap and easy to rule out.
 
Could be wheelspin? I always get advised not to dress the tyres for a week or so before any dyno session as whatever that compound is that makes rubber look shiney apparently also reduces friction and can cause tyres to spin where they otherwise wouldn't.

Did you have dressed tyres?

Or maybe it wasn't strapped down as tightly as it could have been.
 
Hazz said:
Could be wheelspin? I always get advised not to dress the tyres for a week or so before any dyno session as whatever that compound is that makes rubber look shiney apparently also reduces friction and can cause tyres to spin where they otherwise wouldn't.
Click to expand...

I've always found tyres to be less grippy after lathering on a load of tyre shine gel especially!
 
Hazz said:
Could be wheelspin? I always get advised not to dress the tyres for a week or so before any dyno session as whatever that compound is that makes rubber look shiney apparently also reduces friction and can cause tyres to spin where they otherwise wouldn't.

Did you have dressed tyres?

Or maybe it wasn't strapped down as tightly as it could have been.
Click to expand...

Major wheelspin is usually obvious by a sudden drop in the curve followed by an oddly fluctuating or sawtooth line.
It could theoretically be a very high level of wheel slip, though given the tyres fitted and the - relatively speaking - tame power level it is unlikely to be the cause unless they'd been soaking in a puddle of oil for a week :)
 
Seeing the graph would certainly help.

I was only in my EP3 when I was told don't dress the tyres. They're torqueless and relatively low bhp but apparently that's still enough to cause some slippage.
 
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