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Performance modifications
I have done every performance mod to my 2015 xkr convertible.
1. Tune and pulley 2. 200 cell cats full racing exhaust 3. Hi flow air filters 4. Car has been lowered 5. 305/30/20 pilot super sport rear 6. 265/35/20 pilot super sport front 7. New wheels that are forged and lighter. Anyone know of any other modifications including engine work? Wanting straight line performance. |
Methanol injection, E85 conversion, nitrous, headers...
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Jahammer I can't find any company that makes the headers. Do you know of one? Maybe I can have them custom made. Anyone do dyno work to establish what type of hp it adds?
Thanks |
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Throw away the Michelin Pilot SSs, use anything (literally) else.
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An overlooked mod (I think) is boring out the throttle body. It is most effective with "suck through" intakes like your Jaguar, as compared to "blow through". Maxbore.com throttle body boring service and repair is the man to do this. Made a noticeable, but minor difference on my '07 XK (N/A).
Anything you do to materially cool intake air temp is very beneficial. Do research aftermarket intercoolers. You will probably have to do your own research - don't expect someone to offer you a "kit", but if they do it will be very expensive. Nitrous is a great mod for the street - it is cheap and unobtrusive. It is there when you want it (keep the bottle full); and produces a wide powerband. |
Originally Posted by Cee Jay
(Post 1602890)
Throw away the Michelin Pilot SSs, use anything (literally) else.
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Originally Posted by Rey
(Post 1602927)
An overlooked mod (I think) is boring out the throttle body. It is most effective with "suck through" intakes like your Jaguar, as compared to "blow through". Maxbore.com throttle body boring service and repair is the man to do this. Made a noticeable, but minor difference on my '07 XK (N/A).
Anything you do to materially cool intake air temp is very beneficial. Do research aftermarket intercoolers. You will probably have to do your own research - don't expect someone to offer you a "kit", but if they do it will be very expensive. Nitrous is a great mod for the street - it is cheap and unobtrusive. It is there when you want it (keep the bottle full); and produces a wide powerband. |
Here in the UK I had my 2011 XKR tuned top pulley filters and mapped by Viezu it ran 503bhp standard on there Dyno then 560bhp after .They do a further tune bottom pulley and charge I/C sports cats tweak the map 650bhp .
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Originally Posted by carmannn
(Post 1602759)
I have done every performance mod to my 2015 xkr convertible.
1. Tune and pulley 2. 200 cell cats full racing exhaust 3. Hi flow air filters 4. Car has been lowered 5. 305/30/20 pilot super sport rear 6. 265/35/20 pilot super sport front 7. New wheels that are forged and lighter. Anyone know of any other modifications including engine work? Wanting straight line performance. |
Originally Posted by steve_k_xk
(Post 1609538)
In oz we have a type of fuel called e85 which is roughly 105 Octane with a decent custom dyno tune I wouldn't be surprised if one could picked up another 35-40whp
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Originally Posted by carmannn
(Post 1602759)
I have done every performance mod to my 2015 xkr convertible.
... Anyone know of any other modifications including engine work? Wanting straight line performance. A little plastic box, weighs probably less than a pound, but man does it perform! If you're concerned about the weight, just skip the burrito before track time. |
Originally Posted by steve_k_xk
(Post 1609538)
In oz we have a type of fuel called e85 which is roughly 105 Octane with a decent custom dyno tune I wouldn't be surprised if one could picked up another 35-40whp
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Originally Posted by jahummer
(Post 1602995)
Unfortunately Cee Jay had a very bad experience with his tires. I have had almost every brand of tire including multiple Michelins and so far the PSS has been the stickiest for the money and I have had no issues with them. Since he had those defective tires, there have been reformulations.
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Steve K - Answer to my experience with bored throttle body. The bore of my stock throttle body is 82 mm. Www.maxbore. com did the boring to 85 mm. Cost now is $125 and MaxBore turn around is about 24 hrs.
Larger throttle bodies are an easy hp gain. I wonder if Jaguar/anyone has produced a larger bore throttle body that will interchange with ours? Had a '05 Cadillac CTS-V with stock 75 (aprox) mm throttle body. Went to a 90 mm aftermarket from TPIS, but this required also a new manifold mount. OEM manifold is a plastic compound, and new mount was glued onto manifold. I think Jaguars would be more complicated. |
Originally Posted by jahummer
(Post 1609557)
See post #2 ;)
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Originally Posted by jahummer
(Post 1609544)
We have that here too, power gain is a bit higher than that but because the specific gravity is different from gasoline, you would need larger injectors and a more powerful pump plus a PCM map to account for fueling, etc.
As you and i know both chasing extra hp is quite an expensive |
Originally Posted by Rey
Steve K - Answer to my experience with bored throttle body. The bore of my stock throttle body is 82 mm. Www.maxbore. com did the boring to 85 mm. Cost now is $125 and MaxBore turn around is about 24 hrs.
Larger throttle bodies are an easy hp gain. I wonder if Jaguar/anyone has produced a larger bore throttle body that will interchange with ours? Had a '05 Cadillac CTS-V with stock 75 (aprox) mm throttle body. Went to a 90 mm aftermarket from TPIS, but this required also a new manifold mount. OEM manifold is a plastic compound, and new mount was glued onto manifold. I think Jaguars would be more complicated. If you have an ODB11 scanner you can take the maf lb/min reading to determine whether your mod has increased airflow |
Steve, no testing before/after throttle body boring. My Jaguar is the n/a base model. I was interested in a bit more top end power for high altitude driving, with no driveability/gas mileage loss.
The electronic throttle body control acts much like a constant velocity carburetor, so there is no bogging at low rpm/high throttle opening with a larger bore. You can easily "do the math" to measure overall throttle plate area before and after. Bore area will only tell the absolute maximum potential airflow. Read somewhere (cannot find the quote) that "suck through" throttle body supercharged motors like Jaguar are much more responsive to throttle body bore size than "blow through", like Paxton. |
I know it has been mentioned before, but how about a wet Nitrous Oxide "Cheater" kit?
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