Hi!
just a quick question as people with experience might be able to point me in the right direction.
i filmed a 3.0 2003 stype doing a 0-100kmh run, and i took the first youtube video with the same run and car from a guy named GAS ZURICH (credits to him) and snapped them togethe for a comparison.
To be pointed out:
tires:
-His car has the stock R16 Spirith wheels (225mm wide tires).
-car i was in has R18 Mercury wheels (245 40 on the front and 265 35 on the back)
Gas:
-i dont know what gasoline he was burning, but since it's an austrian/german video i assume 98 or 100 european octane.
-the car i was driving had 95 european octane.
This car had its injectors cleaned, and fitted new injector filters. main gas filer is new.
air filter is new. New imt Orings. All carbon deposits were cleaned, new plugs and gasketf for the manifolds too. Maf is clean, throttle body is clean. You get it
Car has been taken good care of.
Conclusions and screenshots below:
(im trying to post the video as a reply to this post)
(videos are synced as so both cars are starting at the exact time)
The S type that im driving gets slower after 4000 rpm!
any ideas of what to check? Or why that is?
could better gasoline and the narrower tires do such a big difference in acceleration?
When the german Stype gets to 100kmh, im doing 83kmh.
PS. I know acceleration runs are sensitive to parameters, but there must be an answer for this phenomenon of being slower after 4000rpm
He has the earlier model. Yours is later. They have different engine management, induction system and power output.
This assumption is based on the two sets of instruments being different. Yours has the later style.
He has the earlier model. Yours is later. They have different engine management, induction system and power output.
This assumption is based on the two sets of instruments being different. Yours has the later style.
not true. cars are identical years and execuitive models
Interesting. I wonder why the instruments are different.
The Germans like a bit of speed. Do you think his could have been remapped?
they are the same, but the bottom video is during the night. non facelift s types have like an older font to the text and different needles.
who knows about the remap... but his car is stock and what remapping could he have done to a stock setup, hmmm. tho' im sure he's got the best gasoline.
Quote:
Originally Posted by JagV8
Could be as simple as part-blocked cats.
Possibly some other restriction... fuel pump not quite as good as it could be or... not sure.
i know nothing about cats so i will post pictures of mines. one looks a bit dark. what's your opinion on this?
sorry for the bad quality i had a video of them and i triad to get the best frames.
My guess is the dark one isn't working properly. If it was it should have burnt the soot off.
Thanks a lot sportson!
i will use a seafoam similar product for europe, from liqui molly... even tho im not a fan of the company, they seem to do some quality stuff.
so i will use their intake and catalytic converter cleaner. its got very good reviews on the usa amazon.
meanwhile i think what jag v8 said might be true too. an old fuel pump. if only i know how to check its efficiency.
then i think comes the fuel that i was using is inferior and and the bigger wheels.
i will measure compression too.
BTW!! the injectors were cleaned and had their filters changed. do you think they could have fitted worse or smaller filters? or are they standard?
BTW!! the injectors were cleaned and had their filters changed. do you think they could have fitted worse or smaller filters? or are they standard
I would think the filters are standard and very much doubt they are likely to cause a problem. How were they cleaned though? Were the shutoff and spray patterns checked after cleaning?
Engines often vary in efficiency. Your idea of a compression check is a good one. Cam lobe wear, harmonic balancing, or lack of, carbon build-up, valve seat wear, incorrect valve clearances, stretched timing chain, clogged air filter, clogged or leaking exhaust, oil viscosity, outside air temperature, tyre pressure, and many other things can contribute to differences.
If your larger wheel and tyres have a greater rolling diameter then it would effectively make your gearing higher, slowing your acceleration.
Also bear in mind that a clogged cat can make your Jaguar run like a dog (I tried to get as many animals into this sentence as possible. Did you notice? I couldn't get more than four though ). Don't be too surprised if your cleaner stuff doesn't rescue the cat. It's worth a try, but it might not work.
injectors were cleaned with a special device with gradated glass towers to check if they all spray at the same rate, using cleaning chemicals.
yeah! i bet i was slower due certain parameters, actually my lpg kit might have changed some fuel trims, remember we were talking that its not calibrated?
i will calibrate my kit, change the oil, add 98 octane fuel, run the aditive first actually, and redo the test.
thanks for the awesome info
injectors were cleaned with a special device with gradated glass towers to check if they all spray at the same rate, using cleaning chemicals.
yeah! i bet i was slower due certain parameters, actually my lpg kit might have changed some fuel trims, remember we were talking that its not calibrated?
i will calibrate my kit, change the oil, add 98 octane fuel, run the aditive first actually, and redo the test.
thanks for the awesome info
Also you usually lose a small amount of power when running on LPG. But it should go back to full power when on petrol
Also you usually lose a small amount of power when running on LPG. But it should go back to full power when on petrol
yeah, but the car was on petrol. i guess the lpg messed up the trims so pinj was a bit lower.
but still, why is the car faster until 4000 rpm, then is slower
yeah, but the car was on petrol. i guess the lpg messed up the trims so pinj was a bit lower.
but still, why is the car faster until 4000 rpm, then is slower
It could also be your VVT isn't working correctly. Something could be gummed up or you have the wrong oil. Old oil or the wrong viscosity can effect hydraulics. One of the VVT solenoids may not be functioning properly.
hmm, any way of cleaning them without removing the valve covers? thanks
I don't think so. I don't know much about the VVT system on this car. But I know it is not possible to remove the solenoid without removing the cam cover. One of the Jag technicians on here might know more about this.
I recently fitted one new one on my car. It cost about £120 including postage from the USA. I didn't do the other one as it was only rattling on one bank.
It is very difficult if not impossible to compare two cars like that?
Unless he went to a track with 3rd party verified speed and timing devices this all internet smoke and mirrors.
We have even had people post phone videos where they are driving around squealing the tires to "prove" how fast their cars are.
That is worthless!
You need some real data as your car might be working just fine? Do you have any timed acceleration data for your car?
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Club makes a good point. Does the car feel ok to drive? If it does, unless you plan on racing the car, why worry? Making your car the fastest motor in town can get very expensive.
). Don't be too surprised if your cleaner stuff doesn't rescue the cat. It's worth a try, but it might not work. 
