P8 I would have to check with Chris but I believe that's correct.



The dyno data we have shows 650BHP with the crank pulley. 408-491WHP, and 428-479WTQ. Your conversion from 408WHP to 542BHP is 0.7537 which puts 491 right at 652. Give or take a couple.



Similar math gets you 578 ft/lbs of torque. Anyway, the most interesting part of the graph isn't the peak differences, but the average gains/under the curve difference. It's basically the whole RPM range, you have some pretty big gains in torque and BHP. Bearing in mind yours is an SVR, so peak torque is the same as the R but your BHP will be a touch higher stock.

 

Those gains look incredible, would you recommend the intercooler upgrade to support running the lower 18.5psi pulley?

Also would I need colder spark plugs?

Finally as I enjoy drag racing and how well the SVR puts power down, with your tune I assume to gain so much torque by tweaking the torque tables and torque limiters, as such once tuned will the car start to just light up tyres in 1st gear or will it still launch as effectively as it does stock?

If there is launching problems is it possible to have the tune with factory torque limiters in place in 1st and 2nd gear to have no detrimental impact on 0-60 and traction off the line?

In your tune do you make any adjustments to the ZF8 and DBW along with throttle maps too?

 

We haven't found it to be *necessary* to upgrade the cooling, but then, I would rather have more cooling than less. You can never have too much.



Same with cooler plugs. Usually the old rule of thumb is 1 stage cooler for every 100BHP. The only thing with the cooler plugs is they don't have the same iridium durability rating so you would need to change them 2-3 times as often as the OEM.

In the UK, it doesn't get that hot. You can probably run just the crank pulley & tune and not run into any problems. A circuit trackday might be a different story.


You'd have to talk to Chris about alterations on the tune but I think

 

I have upper & lower pulley w/ catless downpipes and tune. When youre driving around town or enjoying the highway, its fine even at 85 degrees.

As soon as you push it, and push it hard, it will studder and skip and go into limp mode from the heat.

 

I've run my car hard for 5-6 hrs straight (rally life) and had zero cooling problems. Running a V8, with crank pulley, and tune.

 

This doesn't sound right but then again few have both the upper and lower pulleys as most only do one so your issues could be there but it could also be in your tune so who is your tune from & does it take into consideration that you are using BOTH pulleys?

 

My initial thought as well. JJ didn't even mention a tune. I know for a fact that when the OEM tune sees more than 18 lbs of boost it throws codes and puts the car into temporary limp mode. That emergency is what led me (both pulleys on a V6) to give VAP a shot even though they had little history with the F-Type community. Thank you Stuart & Chris.

 

VAP supplied my tune. Yes, they assured me the tune was correct for both pulleys, and advised me against doing both with stock cooling. The car feels absolutely incredible, as I have said, and Chris has been 100% helpful. We are going to dyno the car and try to log the info and send it to him for a revision. I am looking into a new air intake and heat exchanger as well.

 

 

Heat exchanger same thing as the intercooler radiator for the SC mounted at the front of car?

When I tune my route shall be:
- VAP tune
- Lower VAP pulley
- Intercooler upgrade
- Maybe highflow cars.
- One range cooler plugs


I like the idea of keeping things as cool as they possible can hence me doing the RAM AIR setup on mine and looking into separate header tank for the SC to further aid cooling.

But before I tune, my mission is to try and get as close to 10s as possible running stock tune by simply reducing weight and improving cooling.

 

 

In some service documentation, Jaguar also calls this the "supercharger radiator."

Cheers,

Don