wow, ok, so you did reset the ecu... interesting. as i said, i'm not familiar with Jag ECU's so that might be a difference. and you're right - the data won't change, but what the car does with the data will. in other words, if it's receiving data that tells it that there's more air, it might try compensating with fuel; and if that doesn't work, then it tries timing; then it tries variations of both that it can't do without the car being run in a variety of conditions. but if you reset the ECU, than all this might be moot. maybe Jag ECU's have a different process of working things out. so you're right - data is data. but how the data is interpreted can be a speculative endeavor.

on a side note, s that mina gallery intake designed to be used with a supercharger pulley? because maybe they designed that to trick the ECU into fueling more, to compensate for increased boost. that way you wouldn't need a retune. but i have no idea, i'm just guessing.

regardless, thanks for the information - i'm learning things every time i sign on to this board!

 

The ECU provides a lot of headroom; to give you an example on my '00 XKR I have achieved 455 rwhp (on an Eddy current dyno with load), without any ECU modification. As long as there is enough fuel bandwidth and the MAF isn't pegged the ECU will continue, and I haven't reached the maximum yet.

Wouldn't give automatically credit to a company selling stuff (learned my lessons now), if you want to know ask them specifically what sort of research they have done and at minimum some dyno slips and under what conditions these where done. Anything that alters the airflow reading (even it is just within the limits before the ECU will throw codes) will also make diagnosing issues a pain.

Andre.

 

Andre, what all have you done to your xkr? are you running the twin screw s/c on your car?

 

WOW! Good to know thanks man!

 

Yes I have a TS, that has helped a bit ;-).

 

nice!

 

After struggling with an underpowered air compressor, a lot of grinding, and some spilled coolant, the new 2.5lb pulley is on along with the t-stat.

And here are the results:

-1st pic is flow comparison with the new pulley,
new pulley colors- rpm=red, MAF=blue
stock pulley rpm=blue, MAF=red
stock intake gray

-2nd pic is stock pulley/t-stat intake manifold pressure an coolant temp

-3rd pic is new pulley and lower temp t-stat manifold pressure and coolant temp

I'm very happy with the results - the cars feels so0o0 much stronger throughout the rpm range. In the 1st pic, you can see how much quicker it is to hit redline. The thermostat lowered the coolant temp almost exactly as much advertised. Intake manifold pressure stayed pretty much the same even after the pulley. This makes me wonder where the sensor is located - apparently it's not a good indication of the actual s/c boost.

 

Awesome blaksplash! Thanks for posting the results. Now I am second guessing my readings for manifold pressure...I also indicated around 13.5psi of pressure with 14psi spikes here and there. Anyways, my complaint to the Mina Gallery about my apparently false underboosting situation allowed me to obtain a large discount on their exhaust!

Does the car feel stronger after sitting idle for a while? I know my car feels very sluggish after sitting at a stoplight for a while...I wonder if the low-temp thermostat has any effect on that.

Will you be taking your car to a dyno in the future?

 

that's awesome about the discount on the exhaust! Exhaust will be my next mod. Maybe i could do the same about their intake kit i bought.... did you go with a cat-back or just the rears? I want to hear a good clip of their exhaust kit.

After sitting at a light, the car feels a *little* sluggish, but not much. Power is still up there. When i get a chance, i'll do another test on intake temp to see what degree difference there is after a 60-70 second idle. I'd be interested too see if my heat-wrap makes any difference there. Hmmmm, i may just do that on the way home from work today.

I currently don't have plans to take it to a dyno... though i'm definitely interested in taking it to a drag strip, especially if i can get the launch right. Now it's even tougher b/c of the extra low-end tourque.

 

Hey if you e-mail them saying that you are not satisfied with the results of the intake, they may give you some discount on something!

I only got the rear boxes...I did not know that the Mina Gallery offered anything in the form of a catback. Either way...I cannot justify paying a few grand for a catback which I can get fabricated for only a few hundred.

I was going to go to a drag strip this weekend but things got in the way...If you do end up going, be sure to post the times. I would think your STR would be easier to launch than my XJR considering you have fatty 285's on the rear whereas I only have 255's.

 

how good of a deal are you talking about... ? I've been leaning towards a couple of magnaflows with some new tips, but i could be swayed. their initial price is a bit steep.

oh, and you're right, the don't have cat backs.... i was thinking of eurotoys

here is a couple temperature samples from yesterday afternoon. the outside temp was 89 deg F

first SS, the intake temp rose about +14 degrees after about 100 seconds idling. idle started @ the 100 mark

second SS, after another 3 minutes ( around 5 minutes total), the intake temp was at +23 deg. Also check the coolant temp of 198! most of the way home, about an 18 minute drive, i was cruising in 2nds gear mashing the gas a number of times, trying to get the temperature up there. the coolant temp got up to about 210, but after just a few minutes it dropped down to 198. The new thermostat is working great.

But i have notice that the air intake temp drops pretty quickly after driving. The stock tube has at least one silencing tube located right behind the radiator/fan... right in the flow of hot air, as well as 4 tubes that sit right on top of coolant lines and t-stat housing. Is the xjr's tube the same? i'd be interested to see if you get similar results

 

...you only increased 23 degrees after five minutes of idling? Something definitely needs to be done about my stupid intake tract.....I cannot believe how much my temperatures increase even after dropping my speeds below 10mph, let alone idling for a few seconds.

I think the factory intake tract for both the STR and XJR are basically the same...I have massive silencers pouring out of every which way just as you described. I should really do something about that...it seems that it might be the silencers that are creating such a massive buildup of heat. Your heatwrap around the aftermarket tube might have also helped to keep temperatures down.

As for the thermostat, I was also thinking about getting one as the intercooler and radiator fluid are in the same loop.

I promised the Mina Gallery I would not advertise the discount but I will PM you.

 

Blaksplash,
That is a hell of a write-up and I'm an English major, that was a very good observation on the mina gallery intake. One of the other members said that it is a hot air intake and it would make the car slower, which you also observed. Unfortunetly I spent the 135 bucks on the mina gallery intake, but decided not to put it on. I just put in a k&n filter which gave it a little kick and I already had a 1.5 pulley put on because I needed to address vacuum leaks underneath the supercharger. My STR feels a little bit zestier, so im looking forward to future posts.

 

I wouldnt go as far to say the conical filter makes the car slower, looking at his stats at full throttle the air temp increase was only 15 degrees but the airflow increase was 6.5lbs. I dont think the temp increase is enough to offset the gain from the increase in air to the supercharger.

 

Best thread ever. You are giving me some info here man.

 

Yeah great thread. Wish we could get some dyno numbers on all that vs stock!

 

thanks for the comments guys!

Don't forget that reading was taken when i used the mina MAF sensor housing, which is smaller than stock. The sensor calibration is for the stock sized tube. As Andre pointed out prior, it thought more air was flowing than actual. I would like to see the reported flow with a conical filter and the stock MAF housing (cut off the stock filter box), but i'm not going to hack mine up. Just replacing the filter and mid section tube gave a true 4.5lb/min.

 

Great info guys......Keep it coming!