There's a term for you that is universal on car forums, or actually heck, any forum that revolves around a specific interest. "That guy". Yep, you just confirmed it.

It is clear to me that you are obsessed with carbon build up. What's interesting is that the common message in all of your "proof" post is that it's a pretty rare and uncommon issue that mostly affected early direct injection engines, when looked at by the numbers. Also, look at the poll results in that thread you linked to! A Jaguar tech himself even posted this in there, "Ive opened more than a few 5 litres to replace the outlet pipe under the intake manifold that obviously requires lifting the intake up for access. Ive not see any apprieciable deposits on the intake valve or ports. And surprisingly theyre fairly clean. I did 2 this week and both over 40k miles."

When it is a problem, yes it's a huge problem but that isn't usually the case. Every one of your links says as much yet you, being "That guy", take it and run with it as if it's the thing that defines Direct Injection engines. It's not.

Also, the last time I checked, this isn't an Audi forum and our jags don't run Audi engines. Sorry to hear about their troubles but they aren't ours. Multiple people on this forum have dyno tested their several year old cars and they are still making as much as or even more than the factory ratings. To listen to you tell it, they should barely be making enough power to back out of their driveway by now.

That's why making blanket statements like getting your car tuned will ruin it, or if you want 30 hp just clean your heads is unacceptably misleading. I'm not saying that no JLR 5.0 or otherwise DI engine can have a carbon problem. What I am saying is that you are making a mountain out of a mole hill and the only reason I'm bothering to speak up is for the sake of others.

 

Stick to the facts without the personalizing if you can.
Yes a head clean will gain 30hp!
No I am not raising any alarm, rather just logic- and pleading to the sense of yours. If all DI engines have shown massive HP loss as result of not having any cleaning action- then doesnt it stand reason that the JLR engine which may be better designed than all the others who have been plagued, would see some fraction of improvement. Unless you think there is some magic that is cleaning the valves?

Perhaps you should just educate the rest of us on your public service crusade how the JLR engine overcomes the carbon problem.

 

I'm familiar with intake deposits on DI engines as I have a BMW 335is (N54 engine) which is one of the worst (best?) examples. I had it cleaned at 50k miles with the recommended "walnut blasting" and yes there was a difference, it ran smoother.

If I have time, I will take the supercharger/intake manifold off of my XFR (70k miles) and take some pictures of the intake valves.

But back to the topic on hand, I highly doubt the tuning that the various companies offer for our cars would affect the amount of carbon buildup. I'll contact a few and see if I can get information on what parameters are being changed during the tune.

 

I merely used audi as one example. EVERY DI manufacturer has had significant headaches- GM, FORD, Acura, BMW, Mini, VW, these are not 3rd world country companies. Its been an insurmountable problem for all of them. While I never said that it was for JLR, its irrefutable that JLR's DI engine would benefit performance increase with returning the heads to factory specs.

And yes it is a mountain- never in automotive has there been a problem that has been so ubiquitous across all manufacturers- in so few miles.

Your stance and wisdom is that no way that JLR is affected by a problem that has robbed the best of designers of 100hp. Incredible.

 

If I may expand on your earlier good point as well regarding a custom fooling with the valve timing. I have several friends with OEMs, and there was millions of dollars to be made if someone could have found a solution for cleaning the valves. What several of them came up with was increasing the spray and keeping the valves open longer. they only found this out by insane amounts of research. I cannot give the benefit of the doubt to a 'tuner' who simply does not have the capacity to do the research. Moreover, they have a perverse incentive, they are in the business of selling numbers, they dont care what happens to the rest- they dont have any warranty or other liabilities. They claim to increase MPG and peak power- there is only one way to do that, change fuel/air/time combination that was put there to solve some other problem.

 

For the record I never said JLR could not be affect. Perhaps read my post again. Anyway, I've said my peace. Arguing with you was never my goal nor intent. Continuing this at this point would become that, which I have no interest in. I can agree to disagree.

 

Have you looked up any of my threads about the tune on my XFR? Received a boat load more torque down low and a whole bunch of HP on the top end. The only thing I had to give up was my money. The car is sooooo much more powerful across the ENTIRE powerband that full traction control steps in quite hastily with just a little pedal effort. With the pulley it made it even more of a torque monster down low.

Now I realize the original poster is discussing an NA tune not FI, but your example was a poor one since I have personal knowledge that no sacrifices have to be made for a better powerband. Hell, I even get a little bit better gas milage now as well.

 

You should not see it as a debate at all. Please. I am certain that I will learn a lot from you and that is my intent for being here. Trust me on this one, I am not the sort to speak for the sake of speaking. Which is really your fundamental argument, that I could not possible know any better. P.s even on a new engine, there are umpteen books written on how to increase hp by polishing. Here we are talking about a known design problem/challenge.

 

Hi, do these tune guys have a site where I can study their dyno graphs. See the better gas mileage is the part that throws the red flag too. A car company would give up their right arm for a fraction of improvement on the MPG and they have multi million dollar departments trying to find every single percent. And here come guys that can improve it- I dont doubt they can, I doubt at what actual cost. I am open to being proven wrong on this and secretly want to be.

 

So what you are saying is that having the valves cleaned would get me a quick gain of 30HP. and that if I want to keep that hp gain, I would have to take the car in how often to get it done? Anyone want to chime in on how much the Jag service department would charge for that job. Let's see..taking off all the intake bits, the throttle body, valve covers, and then cleaning the valves...at a nifty $180 per hour labor rate. would be what $700? and i would have to take it in every year probably? OK...and the resonator delete and middle muffler delete? I should put that back on to choke the engine and create a ton of back pressure so that I can put a counter force on the valves that I just had cleaned right? interesting thought process. Do you want to know what my XF sounds like after the resonator and muffler delete? It sounds like a total BEAST! Panties drop when I drive by. I love it, but I bet not many people who go for a Jag would appreciate that sound. So they put these choke points on the car to make it palatable for the mainstream customer base. My gas mileage has improved significantly since the exhaust mods. Oh, and I should also replace the three inch thick paper filters that I just replaced with the free flowing K&N filters because the engineers would have put K&N's on if they were better than the mass produced filters that Jaguar and every other vehicle manufacturer uses. The mass produced filters probably cost about an 1/8th of the price of a K&N filter for the consumer and much less when bought in the bulk that auto manufacturers buy in... and the filter companies have their hands in the cookie jar of every major automotive maker, so how could a small company like K&N get their foot in the door?.... This is even making me think about a wet kit again...and I've already been talked off that ledge once. BTW... If I could stuff a car seat into a F Type V8, I would have gotten one (or a lotus..lol).

 

Take a look at my posts. Just search Jailbreak Tuning on this forum and you'll find a bunch of my dyno charts. Doing this from my phone or I would provide the link.

And the increase in mpg was not significant, but real. For example, I used to get in the low 22's and now get low 23's average on highway. And I get high 17's to very low 18's average in town where I used to get high 16's to low 17's. The point I was making is there was no penalty and it saves just under a gallon a tank.

The tuner I work with does a lot of their business through word of mouth, but they do have a Facebook page.

 

Guys, Guys..Cool down..Queeny is not shoving any of this down your throats. He makes some valid points although some suggestions seem impractical to do, I'll agree....He is giving his opinion based on what he thinks and knows..understand this is a forum of give and take and of shared knowledge...Perhaps he wiil also be enlightened by your opinions and wisdom as long as you don't burn him at the stake while doing it.


Carry on gentlemen..

 

If you are looking to get that 'feelin' of having had a hand in the design of the car, then go with a mod as this will do nothing for that.

If you want to restore power you lost, and enjoy having everything withing original tolerances than here is what you do every 70,000 miles. Dont do it at a dealer, they themselves have to farm it out.

Clean fuel delivery system, replace filter (you can do that with techron)
Clean and polish throttle body and rest of air passages
Clean heads- walnut blast to remove buildup then polish blast (both steps are cheap, about $75 per head)
Clean tops of piston since you have access to them.

Before doing any of this just do a dyno test and find out if you have lost power- whatever you have lost you will gain.

Find someone good and $1100 will cover it, or you will be in trouble if they put it back together wrong. You see because this is complicated average consumers dont know about this, they rather pour a bottle of something in the tank or bolt something on.

A forum member above had to have it done to his BMW, he should be able to tell you about going rates.

 

Guys I owed you follow up on the tune. Their graphs do show a positive improvement. However a Jaguar Engineer writes the following.

"When I used to work for Jag, I had a donkey from Paramount phone me and try to push me for information.
He didn't offer any payment, but said he would take me out for a slap up meal-Such is the worth of engineering knowledge in the UK.
He didn't know what the hell he was on about- and was talking about using Variable cam phasing in league with the supercharger not understanding basic thermodynamics of engines. But this is par for the course in the UK, where ENGINEERING, mechanics and technicians are all banded together and you're labelled a snob if you think otherwise. I heard in some of the maps of their older X100 modified supercharged offerings they don't remap but simply 'let the knock sensing do its job'. Oh-dear, very bad idea!
Obviously I wasn't forth coming but it was enough to leave me with a very bad impression of these boys.

Just think you're paying money to degrade all the fastidious and painstaking work that's gone into your finely engineered Jaguar..."

 

Upon further inspection of the graph (which was a picture) directly from the tuner- the numbers make absolutely no sense to me. See if you can see whats wrong or perhaps if I am wrong.

 

So the purpose of this is to bash Paramount? I'm not familiar with them. There are good and bad tuners just like there are good and bad plumbers.

Also, yes our Jaguars are very well engineered and designed. However, to propose they cannot be improved upon is a gross oversight and inaccurate. Great engineers, mechanics and tuners are not born and raised on Jaguars campus. There are plenty of excellent companies out there who hang their hats on taking already great products and making them even better.

It only stands to reason that something engineered to suit the wide range of needs of the masses, can stand to be tuned finer and to more exact levels to meet a specific, individual customer one at a time.

So if you are saying that you don't recommend Paramount Performance then ok. But are you using that as proof that aftermarket tuning is bad all together?

 

If Jaguar engineers have done their best with the XF Supercharged, how can you explain the XFR and XFR-S with higher levels of power with ALL THE SAME COMPONENTS? It's foolish to believe that all the performance is taken advantage of at the factory. And up to a certain level, I believe it is free, with no real sacrifice by the owner.

There is the "next level" where one might trade a 10% power increase for a 10% shorter engine life. That might be a good trade for most people, especially if they change vehicles often. However, I don't think that is the case for the tunes from good tuners when power isn't much higher than is available from the factory in higher trim levels.

And then you can go to a point where an additional 30% increase reduces the engine life by 60%. Most would consider that a bad value. But some would still do it...

 

Why would I have an agenda, I am still an uncommitted explorer. You on the other hand have an emotional investment and would hate to have made the wrong choice.

Yes there are other brilliant engineers outside Jaguar, but they probably work for an even bigger company or a formula one team. Yes I will say without mincing words a guy with just a laptop does not have the same tools at the disposal of a Jaguar engineer. As I said I am really looking for someone to top the overall performance without any compromises to longevity. I have yet to see a "tuner" that was anything more than a shade tree guy. All tiny fragments. Why is that? if they can give even 10% more perf without any downsides, they should be as ubiquitous as detail shops.

But please dont see a gun behind every tree, I am genuinely looking to find a credible source of a tune. I am most doubtful I will. In companies like Jaguar where there is a long heritage of producing the most powerful street going cars, as an underfunded underdog, Its unlikely that they have overlooked free horses like a Chevy truck might do. They are now equally desperate for reliability.

 

You are absolutely spot on categorically. Really well said. I wonder how many actually know what you wrote.

Its not the reliability compromise that troubles me. I absolutely dont want to compromise the character that is uniquely Jaguar. Thats why I bought a car that outperformed a Lamborghini Guido in regards important to me, which was its powerband.

My current suspicion is that the tune trade off is far greater than 10%. Just the higher revs will take care of that. What about the tranny only rated to 500hp. What about the extra heat.

 

I don't know what a Guido is when speaking about Lambos except the character driving it may be named Guido.

But seriously, if you've never driven a modified XFR, you don't know about power, torque or character. The stock car is nice. The modified is truly attention getting and gets my adrenaline going every time I pin it to the floor. I have an 07 Kawasaki ZX-10. Before mods my XFR was close to having the same feeling as the bike. After, it definitely had the same feeling. Not saying it's as fast by any means, but the same effortless "I want to go over there" feeling of power.

And my rev limiter stayed at exactly stock. No power gained there. I told my tuner I'd leave power on the table for reliability and wanted power under the curve. I think they achieved the goal quite well.

The one limiter they did modify is the speed limiter. I can now go as fast as the tires, gearing and aerodynamic drag will allow me to. Which I would estimate to be 180 or so. Haven't been anywhere near that, but would like to do 170+ sometime just to say I did it.