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Discussion Starter · #1 ·
I recently had my car on a rolling road and the result was 145bhp @ 275lbs, the graph shows the line going up but right after the peak figure it drops straight down. Ive seen many graphs but never one where the line just drops straight down.

Any ideas?
 

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Discussion Starter · #4 ·
I dont think it hit the limiter and the guy who did the test didnt know why the curve dropped so suddenly.

bump
 

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Maf problem? Was it the power or torque that suddenly dropped? It would make sense if it was the torque as that figure of 275lb/ft seems highly unlikely.
 

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Discussion Starter · #6 ·
it was the power that dropped off. as for the torque 275 is correct (according to dyno).

The bloke who did my remap tried with stock map to make sure rolling road figures were not overblown.

using a new merc maf.

hoping for a solution [:(]
 

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the merc maf is the problem then. I know thos had a problem with a merc maf that did something like this.
 

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what does the Torque graph look like... bhp is all based on the torque figure anyway so if you know what the torque is at a certain revs you can work out what you think your bhp figure should be

Jabba have got some TDI graphs on their web site go and check how it compares
 

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Discussion Starter · #10 ·
sorry the engine is 110 non pd. Im using a new merc maf. reading previous posts i see merc maf's may cause problems with only remapped/chipped pd's.

i had tried my old maf but the dyno refused to give a reading (i knew it was duff because car was slow pulling after 3000rpm).

i will have to buy/borrow a standard maf to rule it out. I can see how the reading on the maf may go out of range causing this 'particular' dyno to stop reading.

if anyone else has heard of this problem please post.

cheers chaps
 

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If your 110 is non pd then I'm even less inclined to believe that torque figure is accurate. That's the torque generated by a chipped 150 with its larger turbo and pd injectors. Are you sure your figure is lb/ft and not Nm?
 

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Discussion Starter · #12 ·
yep that is lbs. my friend pinkys_tdi was on the dyno before me, his was a 130pd and remapped the dyno result was 179bhp (fixed) & 315lbs torque. which was what the remap guy expected. (proves to me that dyno was working fine)

to be honest the remap bloke expected to get more from my car. he has 'custom mapped' many tdi's and did quite a few non pd's.

There was results stored on the dyno's pc and there was 110's (non pd) at 170bhp which he said was a regular occurance. (my problem hopefully will be the merc maf)

There has always been debate over whether a 110 can achieve 170. I guess its a wait and see if proof comes to light either way. he explained how these cars can do 170. which i dont understand but what he said sounded plausable.

i think its time for him to explain to people himself, i will email him now and get him to post. this might even generate some travel from the mainland to n.i. by some tdi owners.

hopefully by tonite we will have some light on the situation [:D]
 

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Quote: posted by bobseptic on 21/09/2004 11:20:21

yep that is lbs. my friend pinkys_tdi was on the dyno before me, his was a 130pd and remapped the dyno result was 279bhp & 315lbs torque. which was what the remap guy expected. (proves to me that dyno was working fine)

I take it that was a typo and should read 179
 

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Sorry Bob but I'm not convinced by this at all. If he's really attaining these figures then he's achieveing stuff that other tuners can't even get close to. I suspect that the dyno isn't being setup correctly for TDi's and that explains these high torque figures for all cars. Try getting your car dyno'd elsewhere where they do know how to set it up and you'll see a different figure. Take for example my car - it's a 150PD with REVO, high flow air filter and Milltek exhaust. The figures I get are 185-187bhp and 285-290lb/ft. I also have nos which takes these figures up to 220bhp and 343lb/ft - much more realistic.
 

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I feel I have to speak out about some of the comments made about

the results that my remaps acheive. ( torquetronix)

Firstly the rolling road which we use is a private rolling road

which is used mainly for testing rally engines. It is well known

to annoy some of the competition boys with engines with what we know

over here as English horsepower quotes!.

We continually test the dyno for base fiqures during development and usually find that we are almost bang on the quoted standard horsepower quotes.

I'm afraid that if you doubt the torque figures for Bobs 110BHP.

U would not beleive that we have a later 2001 Seat Toledo running 171BHP.

and 300lb/ft torque on standard turbo. (Most Later ECU's are more tuneable given the way their fuel/boost maps are written.

Early cars struggle to deliver more than one bar boost.

These values are not spikes and continually repeat!.

To answer the PD question.

I have rarely seen less than 300lb/ft from a well remapped PD

engine. If you are only getting 180BHP from a 150 PD with a remap

I would be looking for my money back.

195+ is easily acheived.

I run my Golf 130 with hybrid turbo,modified intercooler, exhaust

etc. currently at 350lb/ft torque and 245BHP.1.9 BAR MAX

This torque fiqure is to high for the standard gearbox but the car

is just to show how far we can go. (Although it is used every day!.)

I have friends in Germany who have experimented with PD Engines

running up to 300BHP on special fuel mixes and Larger injectors and

modified Cam lobes on the injector rockers etc.

With a hybrid turbo 220 BHP + is not a problem with a PD engine.

I generally tune down the torque to save the gearbox.

I think that I should point out that with remapping there are various ways of modding the electronics to achieve more performance other than just modding basic fuel and boost maps. For example take a 90BHP TDI.

Superchips will mod just two maps and their repeat versions.

They basically mod Boost request,Boost cut and overboost as well as the final quarter of the main fuel map.

I mod four maps and their repeats to acheive the result I require.

With the PD engines again it is possible to map three main maps

and their repeats to acheive an average result.

To acheive serious torque and help the engine to rev quickly much more

has to be done. Most of these mods are fairly unique to myself and some friends in Germany. We can extend the power range and help the engine rev quicker, I see max power with my own car at some 5200rpm.

Generally Merc Mafs on high boost cars produce a higher reading and force the data in the ECU out of range. This can sometimes cause a power drop at higher rpm. This is usually too high in the rpm range to warrant any concern. This problem can be mapped around and involves changing Parameters governing MAF to s elect different lower map values.

I hope some of this info helps.

If anyone wants to have a remap by myself u can either pay us a visit

here in N.I. or alternatively post your ECU and I will reprogram it mostly serially but some VM+ ECU's 110BHP(check the label) require the

ECU to be opened and the chip removed and reprogrammed.

I charge ?350 + Post and Packaging.

E-mail for address details.

PS . Website should be online in the next month check out

torquetronix.co.uk
 

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Dataman can you tell us why all these other tuning companies don't get figures like you quote? After all they also know what they're doing and many have a racing background. As I'm sure you know there are a limited number of parameters that can be changed on the TDi's to achieve the power gains so what's the secret to these higher figures? Have you taken the rev limiter off your car as the TDi doesn't even rev to 5200rpm. If so how are you managing to burn the fuel? As for your comment regarding turning the torque down to save the gearbox, surely the clutch is the first thing that's likely to go? Can you give us some more info on these larger injectors as I've heard about some once before but didn't know they were actually available.
 

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Here's my 2p:

We logged 1.9 bar of boost on my car and 185bhp and 279lbs/ft. So how do you get your higher figure with the same boost level? At 300lbs/ft it produced unacceptable levels of smoke and the clutch slipped like hell. It struggles with 300lbs/ft, so would be destroyed with 350lbs/ft.

My '98 AHF TDI managed 1.2 bar with ease.

How can you achieve such high figures without blowing off the cylinder head? Remapped pd's have dangerously high cylinder pressures.

The VNT15 turbo will NOT work reliably to those power levels you quoted for the Toledo.

It just doesn't add up.
 

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@ dc i doubt your car is running 1.9bar constant boost, no way. that 1.9 bar is probably overboost, thats when you floor the accelerator and the turbo spools up until it then settles back to maybe 1.6 bar constant, all turbos do that cos they rapidly speed up before they can be controlled by the waste gate,a standard turbo would burn out at 1.9 constant. you can check what boost you are running by looking at vag com by looking at requested boost when you boot it. dataman may mean his is at a constant 1.9bar which im sure could be possible with a hybrid
 
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