First of all who did you speak to?

Lower pulley is best bang for the buc

200 cell cats and a free flow exhaust will give more than 8bhp more like 15 I would of thought but this will not be spread over the power range more at the top end.

I would not do both pulleys unless you are going to do some serious cooling, alot of people opt for the top pulley because it is easier to get at but if you go for the really small one it will cost just as much unless someone has developed an easier way of cutting the nose down instead of standing there with an air file for most of the day

ECU remap will give something if you can find someone who can actually change the map instead of just uploading different ones and seeing which one works best, as far as I know there is only one piggy back system that seems to work but costs ££££s

In an ideal world you would have exhaust, pulley, induction and then a proper remap to make everything work as it should, unfortunately that world only exists if you are willing to spend mega money

 

I spoke to Powerhouse

What would my peak power be with lower pulley, full exhaust system including sports cats and K&N panel filter be then? I might just get a lower pulley and call it a day.

 

If you were only going to do one thing, then I'd 2nd xkr racer, the lower pulley will give you the best bang for the buck. You will feel a huge increase in low end power and the power will come on sooner.

Did you see my 0-100 video? You can see the power added is much more than +15 at the top end because of all my other mods.

As far as top end power goes, without adding extra cooling you may only see +15 or so, but is the car going to be only a dyno queen, or are you going to use the gas pedal from time to time on the street?

I have done the pulleys each way

Upper pulley
Upper pulley + port
Lower pulley with port <---very noticeable improvement over upper pulley with port.

You will want to upgrade your cooling. For only $30, I added a 12" fan in front of the super charger radiator and found that very effective, along with adding water/meth injection at a rate of 375 ml/minute (middle of the road amount)

radiator fan: http://www.siliconeintakes.com/produ...839677956ea6cb

and I bought the water injection system used for $300. These come up on ebay and can be had for 3-400 USD from time to time. With the water injection, if you inject before the blower you will gain an additional +1 psi of boost. Those that say otherwise have not done it themselves. The water vapor helps the blower seal better and gives it denser air which is easier to move, so it makes it more efficient.

The porting added no less than 1 lb of boost for me, AND ported blowers are known to run cooler as well, which is significant.

Also very important is to reduce the vacuum before the blower so in order of importance/most restriction:
3.5" true 90 degree sweep bend into TB is the biggest restriction in the stock intake
then I would opine a larger intake tube
then larger mass air meter

If you want to keep the stock maf, I did notice an improvement by adding an additional 2" opening in the air filter box (before the filter) and running a 2" duct to cold air. The later 4.2 liter engine air filter boxes did have an additional opening, so that lends credibility to my experience as well.

Again, I have actually tried all these things myself and felt the increase in acceleration myself.


p.s. I did the high flow cats 200 cel. They sounded really good, gave somewhere around 10-12 hp, but do not pass visual smog here, so for me, they were not worth it.

 

Not a bad idea to go for baseline dyno. 155K miles engine, if it's orginal one, may not give the same power as 15y ago....

 

Hi there,
Not interested in dyno figures at all tbh, Its more for the street side of things as you put it and beating my existing 1/4 mile time. Also there's an annoying driver near me in an Evo FQ340 that just beats me and I want revenge.
I want bang for buck and it seems the lower pulley would be my next option.


Holding out high hopes for the Cats on Saturday as mine are currently f*****. I want over 400bhp in theory.

 

If you baseline is for example 330bhp, hard to reach 400bhp with simple mods. That's why I asked to dyno it first.

 

Well, the lower pulley alone will make a huge difference, especially across the intersection from a dead stop. If you were to do one thing to get the best improvement from a dead stop that would be it.

The dyno queens only tell part of the story, it is the total area under the curve that determines performance.

I am pulling more than 15 psi of boost before I clear the intersection from a dead stop, just at the limit of traction with cold street tires. (when I say cold, I mean California cold, for example it is 72 degrees F today)

I have left more than a couple of "fast" cars sucking my exhaust from a dead stop and then watching them mouthing "WTF" just happened??

Then they catch up and see my XJ8 badge and really are thrown for a loop


My advice if you want to keep it simple, easy, and relatively cheap is to get the lower pulley and $30 inter cooler radiator pusher fan and then go spank that Evo and video his face while doing so Then report back

 

Most say a bottom pulley will grant you 10% more power so in theory an extra 35+ BHP, unless you do before and after dyno you will never know for sure and has been mentioned depending on age and mileage some of those horses have probably escaped.......

I have heard of good results from a decent air induction and a bored out TB maybe with some water/meth injection you could get a tad more........

I am tempted to give my own XJR some goodies but I would want a manual box, LSD, and a twin screw quite like the look of the liquid cooled Kenne Bell just to be different, but we talking money

 

Best mod I have ever done to any car, ever.

Search for "electric exhaust cut outs" for more info.
Vector

 

Ok, Sports Cats are fitted and I'm pleased with the results, seems a more positive pull from the car now. I've uploaded 2 videos, the first shows my speedo 50-90MPH in 7 seconds, the second video shows the same speeds but a second quicker. It actually now takes 5 second to pull from 50-90mph but for some reason the video buffering adds another second to both videos. My old Cats must have been in poor condition.

One thing which I'm not sure if it's anything to worry about, the chap that fitted them advised me the left-hand exhaust bank had a lot more black soot in it than the right-hand side which was near enough clean. Now 1200 miles ago my right-hand bank suffered from HGF so the water could have perhaps cleaned that side, but it was a while ago now, what do you guys think?

 

If you are going to do an upper or lower pulley add a reservoir tank to the intercooler circuit to reduce heat soak.

 

Whats the ticket on that Tank?

 

I had it made by Dad's Tanks from my drawings. I moved the filler for the washer tank up in front of the A/C dryer. The tank is plumbed into the intercooler circuit at the pump. Holds 6.5 quarts of coolant to provide additionally cooling capacity and delay heat soak. Pump is stock

 

I went the route of adding things that actively cool in real time over adding more volume of coolant. It has worked well for me.

I do not experience anything beyond very mild heat soak.

I'm running 18-19 lbs of boost on just a lower pulley on a ported blower.
Stock showed 9.5-10 on my gauge
+4 lower pulley gave me about 3.5 on the stock intake to 13
+2-3 Larger MAF, intake tube, maxbored TB and portmatched elbow to 15-16
+1 ported blower (also makes it run cooler) solid 17 psi
+1 Water/meth injecting before blower vs after to a solid 18 psi at 70-80 degrees F ambient temp

I added a 12" pusher fan in front of my inter cooler radiator. This alone made a noticeable improvement in heat soak

Then I added water/meth injection and I no longer notice anything beyond mild heat soak.

My fan was only $30 from siliconintakes.com and I've seen complete water/meth kits used on ebay for $300.

If one is using stock maf, intake, tb, and unported blower with both pulleys, you will need a lot of extra cooling.

note: I added the larger bosch 010 inter cooler pump, but did not notice any change, probably because my temps were no longer very high.
I also have set up some fine mist spray to spray on my inter cooler radiator at the touch of a button to be used when I'm really serious.

 

I was able to get both of your videos running at the same time to see the difference. Your cats must have been clogged. Congrats on getting that fixed. Fun Fun Fun

 

Cool how did you do that?

 

The low tech way. I ran one, then paused it, then ran the other, then clicked play on the first so they were both playing at the same time. Mine is a very crude technique, but you can see the after accelerates faster than the before.

Like I said, the low tech way

Ideally, next time allow a few seconds more of lead in before the action starts as I've found it takes the camera a few more seconds to actually begin recording after it says it is.

On my 0-100 video I waited something like 10 seconds after pressing record on my phone and ended up getting like 2 seconds before the action.

 

Yeah I have the full video, I had trimmed it down to send to my mates via the mobile and just uploaded that one, but I can upload the orginal if need be.

 

Oh and the noise.....