My XJS had a fuel line cooler that was connected with the A/C system. Fortunately that bulky old compressor is one of the first items to jettison from the engine compartment. My cooler was on the fuel return line, not the feed. Seemed odd to me. I'm also ordering headers for the exhaust system. I'd like to get rid of some more weight under the hood. I have the 5.3L so every pound helps.

 

headers on the v12 have no performance gain over the stock cast iron other than weight, I more than made up for it by ditching the bumpers I'm gonna post up a separate build thread with pics tomorrow.

 

They all were, the reasons being that the fuel (a) is not under pressure and (b) is cooled after being heated by the engine and (c) is cooled just before it goes back to the tank.

The reason, I believe, for the cooling was to reduce evaporative losses from the tank, nothing to do with fuel temp in the injector rail. The temp of the fuel in the tank could apparently rise to 50°C on a low fuel load! Whether the system had much effect, or was really needed is not clear, as the later models got rid of it.

Greg

 

That certainly made sense. Thanks for the insight. My XJS is completely stripped, no bumpers or anything I don't need on the track. I replaced both floor-pans with much heavier gauge steel to support the roll-bar and used the same steel to seal off the fuel tank from the driver's compartment. That put another 25 lbs back on the frame but it sure made the body more rigid and stable. I'll try to get some pics up when I get her ready.

 

it'll be interesting to know the final weight after all is done, ready to race!

my XJS rodster, is an actual scaled weight of 3360lbs,1/2 tank fuel, no driver.

drives much more responsive than the 4100lb factory car, like brakes, quick turnin, acceleration, more nimble.

being an open car tho it is somewhat flexible, but it aint no race car, just a fun to drive hi-way cruiser, garage queen,and show car.

 

That's a great looking XJS! What are you running for brake fluid? Do I have to run Girling fluid in an 87? I'm going to be tearing down the brakes soon after i change my front cross member. Hate to put the wrong fluid in and ruin it. I had heard on a separate forum that the seals were synthetic by then. Is that right?

 

You do not need the "Girling" fluid. Just do not use DOT 5 fluid. That is silicone and has way too many issues to be used. Go with a good DOT4+ fluid and change it yearly.

 

Whew! Thanks for letting me know. I use a good DOT 4 in my 87 XJ-6 so that had me worried. I have yet to get into the brakes on the 87 XJS yet. I greatly appreciate the tip, Kev

 

Still wondering about the EGR system. Does anyone know if it (the EGR system)can be removed from the engine permanently for racing use only? Love to pitch all of that as it's just another potential failure on the race track and really only designed for pollution control from what I know. (I know I left myself open there) Will it cause problems with the computer? The cats have been eliminated and MiG welded to 2 1/4" straight pipes and it doesn't seem to impact the computer at all. Suggestions?

 

YES, you can eliminate the EGR system.

 

Thanks! Any vacuum issues to worry about or special considerations? Thanks, Kev

 

What size rims and tires do you suggest for the XJS? The stock tires are 215/70/15's just like my XJ-6. I'm racing in the 24 Hours of Lemons so I do have a budget, so to speak.

 

Heating system question..87 XJ-6- my heat comes on normally and then suddenly it seems like the AC comes on without touching any of the controls. It does switch back to heat on occasion too but it is very inconsistent. Anyone have any experience with this Jag Gremlin? I can tear it apart but if someone knows what to specifically look for I would greatly appreciate your input.It has a new divert valve in it. Thanks!

 

Two tips: Search the forum for ac issues for the last few months, there are similar issues there. And if that doesn't help start a new thread instead of "hiding" and hi-jacking this thread. helps you and others.

 

Thanks for the tips on using the forum. I'll check that out. The forum administrator relocated my original thread to this section of the forum. Inadvertently, I started this thread. Please go back to the start and check on my intro post that was moved. I don't think it's possible to hide or hi-jack my own thread. I started it and was involved with several other knowledgeable members when I asked the heating system question about my other 87 Jag.

 

With the title being cross member in the xjs forum you are bound to miss xj6 membrrs who have had exactly the issue you describe. Hence my comment.

 

Thanks, in the true spirit of Jag lovers, apology accepted. Now to dig into those darn ambient temperature sensors!

 

Update.. I bought an 86 XJ-6 from a salvage yard and took the cross-member out of it. That's an involved process but it appears to be fitting perfectly into the 87 XJ-S. Anybody ever done this before? I'm going to install the old CM from the XJ-S in the 86 so I can still move it around.