Why is my car faster than stock?

[kizmo2209]

hello all! I shall start from the beginning...

when I bought my 51 plate cupra back in may, it was advertised as a standard car. However it always seemed quicker than its standard stats suggested.

It wasn't until I removed my plastic engine cover and changed my spark plugs that I discovered a forge blow-off valve fitted to the leon. But this is the only mod visible. Air box is standard, exhaust is standard etc... The only thing i have done to the car are the pipe deletes.

the car itself does 60mph - 100mph in 9.1 seconds which when comparing figures seems a fair bit faster than a stock cupra should be.

I finally put it on a dyno and got my results. I have 191.4 HP and 203 Ftlb torque. the curves are very standard looking, torque peaks at around 3250rpm, cross-over is at 5252rpm and power drops at what seems to be about 6750 after peaking between 6000 and 6500.

my boost seems standard also. peaks at 0.8 bar just before 3000rpm and then drops to 0.6 bar and pretty much holds all the way through the rev range.

so with only a blow-off valve and deletes to go on, this 51 plate cupra with 110k on the clock is makin 191hp and I have no idea why?

blow-off valve suggested it had been re-mapped but then my boost pressure seems untouched! help!

 

[Alexis27]

You mean a Forge recirc valve? It's a like for like replacement (albeit a valve instead of a diaphragm
)

 

[mty12345]

Over reading dyno?

 

[kizmo2209]

It's a decent company the guy I went to and he uses a dyno dynamics dynamometer which are also pretty good. But even dismissing the dyno figures, 9.1 60-100 is quite quick for a "standard" cupra. That puts me supposedly faster than brand new fiesta STs!

 

[Andrewwright]

How was the 60-100 timed?


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[kizmo2209]

Multiple runs on video. Then using a software to break down the video into individual frames to get the time between when my needle exactly passed 60mph and 100mph

 

[Andrewwright]

Out of interest can you put up a pic of the bay? You have checked to see what turbo she has fitted? What engine number is it on the block? Have you spoken to the bloke you brought it from?

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[kizmo2209]

Tried speaking to the bloke but no reply from him what so ever. Engine has AUG I think stamped on it from memory but don't know any over numbers. Will get a picture in the daylight tomorrow.

 

[mty12345]

If it had a different turbo you would get way more than 191bhp though.

 

[kizmo2209]

Somebody mentioned maybe it is remapped but potential boost leak could be holding back the boost? But I don't know how likely that is as the graph looks pretty solid and I don't fancy spending over £100 on new pipes just to find out :L will try post power graph pics too if that helps.

 

[kizmo2209]

Also Matty, just seen your signature thing... it's probably AUQ on the engine not AUG hahaha...

 

[Cupra Ross]

Tried speaking to the bloke but no reply from him what so ever. Engine has AUG I think stamped on it from memory but don't know any over numbers. Will get a picture in the daylight tomorrow.

AUQ. It's running standard boost. It may feel faster, but in reality, it's probably about right. They are quite punchy straight out of the box. Have you owned another Leon 1.8T to compare it against?

 

[kizmo2209]

I haven't had another leon but being standard it keeps also up to 110mph against my Dad's 250BHP mapped Saab 93 aero. Also had runs against old focus STs and pulled away from them. Supposing it's meant to be a standard 177bhp....

 

[kizmo2209]

 

[Andrewwright]

If it had a different turbo you would get way more than 191bhp though.

Not necessarily mate "cheeky punt here", ko4-001 I think could do this..
I'm interested in the fact it's still pushing past 6k which isn't possible with a stock ko3 on a stock map, she will drop of at about 5.5k either way, 9.1sec imo isn't possible either with a stock map on a straight/flat road.

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[mty12345]

Not necessarily mate "cheeky punt here", ko4-001 I think could do this..
I'm interested in the fact it's still pushing past 6k which isn't possible with a stock ko3 on a 0stock map, she will drop of at about 5.5k either way, 9.1sec imo isn't possible either with a stock map on a straight/flat road.

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A KO4 on a AUQ that is otherwise standard...... No exhaust, intake or FMIC etc?............ If i was a bookie, i'd happily give you 1000-1 on that punt,lol.

Having a look at the dyno print out above, the Torque is dropping off at 5500rpm, which as you said, you would expect with a Ko3s.

As for the method of timing it 60mph-100mph.... The speedo on all cars reads over by around 10%. So it's probably more like 50mph to 90mph that is actually being measured, and that should be acheviable by the standard cupra in 9.1 secs.

Imo it's a stock ko3s, being run on a dyno that is reading slighty over.

 

[Andrewwright]

A KO4 on a car that is otherwise standard? No downpipe, no exhaust or intake.......Makes no sense.

Having a look at the dyno print out above, the Torque is dropping off at 5500rpm, which as you said, you would expect with a Ko3s.


Imo it looks like a stock ko3s, run on a dyno that is reading slighty over.

Didn't see the post with Dyno print out before I posted. I was going with replaced blown unit or some other possibility but yes...Dyno lottery.

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[Alexis27]

Just stick a stage 1 map on it and then you'll have 215hp and be sorted!

 

[kizmo2209]

The figures it accelerates at is solely the reason why we went to a dyno in the first place. The dyno only actually confirmed what we first thought about the car. And the point being I don't know what has been done to it and I am looking for ideas/suggestions of where to look for things.

I am on a insurance policy where actually my car is not allowed to be modified. They refuse any modifications which was fine to begin with XD would love to do more to it but that will have to wait until next year.

 

[Andrewwright]

It's already modified some how. No 1.8t auq will put out 190whp as standard with a boost leak. no matter how well it's been looked after.

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