Alex your tune never worked on the n/a 5l you did, it was a fail it ran no quicker .

 

Steve I don't believe it was the tune but an issue with the car. I contacted the owner several times to get to the bottom of it and offered free tune adjustments. If we get it on the dyno and do more logging can figure out what's going on , but it appears he is busy or unable at this time, so nothing I can do on my end at this point on that particular car.
Speaking of 5.0 cars , my recently tuned 5.0 car is currently the fastest XFR in the world I believe . He was at 11.4 1/4 mi last time I checked this is however with 50shot nox and just with the tune he was around 11.9 with bad traction , should be easily 11.7

 

Leave it to the land Of Fruits,nuts,and flakes.

 

A few years ago I had a 1974 Lotus Europa with the Twin Cam engine (130 horse). I was talking to an owner of an S2 (90 Horse). He said one of the great things about his car is that he could drive it at 95 percent and not be breaking too many laws. He reasoned that a lot more horsepower would just mean he couldn't jump on it as much.

 

A mild tune and freer flowing exhaust isn't going to get you anywhere near the 120+hp difference, let alone the torque difference from the forced induction of the superchargers in the XKRs.
The tunes are good for ~15-20hp, and a freer flowing exhaust is good for another 5-10 being generous.

That is still a loooong way from the XKR performance.

 

Ah, I see now, my mistake. Comparing the NA 5.0 to the 4.2L XKR. Yes, that would put it close to parity then.

 

It would if we are comparing stock 4.2 Xkr to tuned 5.0 might be similar , even then 5.0 will be a little slower , but a tuned 4.2 Xkr will be significantly faster than a tuned 5.0 car

 

The easiest, cheapest and most responsible way to do what you ask is, and I'm totally serious here, is to sell the XK and buy an XKR. I'm an old hot rodder from way back and it was my job to make more power from everything I owned. I won't do that on an XK, it's not easy nor cheap to do it other than going XKR. Plus then, you can go up from there!

 

There is always NOX

 

Water/Meth also. Sometimes harder to manage, with extra tanks and such. Plus a tune which goes away when a tank is empty.

 

Nox is guaranteed power where methenol on some cars makes no difference

 

On a GDI meth would eventually clear out some of the gook behind the intake valves though. That alone would be worth a buck or two. I am still considering W/M for that reason. Give it a tiny spray that doesn't really even add any power but just does a mild scrub.

 

Yes it does do cleaning good! I have heard stories that potentially methanol can eat away supercharger blade coating . I have no clue if it's true or not

 

Huh, I've never heard of that. Well, maybe then just a water squirter. If your sentence is correct, that would suck.

 

I did erode the turbine wheel on a vehicle I drove for 100K miles.
I also destroyed a wheel with w/m because the actual injection was more of a stream than mist. The stream cut the tips of several blades off and imbalance was a bit too much for the poor bearing assembly.
I added turbo chargers and associated controls to the following vehicles I have owned:
1973 MB 450 SE
1979 928
1969 Honda CBX
1991 Kawasaki 1100
1985 MB 500 SEC
1988 Chevy 1500
1987 Honda CRX
I added w/m to all of them and also to several NA vehicles.
The w/m never NEVER (on its own) made more hp if the engine was operating @ 11.5~12.5 af and the ignition wasn't being retarded to control detonation.

In the na engines it permitted me to run an advanced timing curve which resulted in better performance or better fuel mileage depending on how they were driven.
In the sc vehicles it allowed higher boost, smoother more gradual drop off of the acceleration curve and it steam cleaned piston tops. It also killed spark plugs if used aggressively. (high volumes).

wj

 

I checked around and found this on the NX site:
"Positive Displacement Supercharger: Roots style (B&M, Eaton, Magnuson, etc.) or twin screw (Lysholm, Kenne Bell, Whipple, etc.) Mounting the nozzle before this style of blower is perfectly safe and actually provides some additional benefits. The small amount of water-methanol fluid isn’t harmful to any rotor seals or surfaces or coatings, and it helps to seal the clearances and condense the air some more, resulting in a more efficient output. Additionally, it keeps the rotors and housing MUCH cooler, which reduces heat transfer to the rest of the intake and air charge."

 

Thanks for the input! This confirms as I suspected from hours of research , that many cars even with force induction applications did not have any power benefits with MI installed without tuning for it. Tuning for methanol injection is also risky if MI fails so can your engine if tuned aggressively for methanol.

 

Mine would be only for a cooler intake charge and the valve cleaning benefits. It'd be a meager squirt.

 

give me a winding road over a 1/4 mile straight, any day. any weather. any time. Or even a slalom track.
show me improvements on that and I’ll be impressed.

 

Go xkr-s suspension and steering rack and you’ll notice a big difference