Does anyone make a set of aftermarket stainless headers for the XJS with the 5.3?

 

There may be some other places but I know AJ6 does, but prices can be hefty I believe

http://www.jagweb.com/aj6eng/exhaust4.php

 

Thanks for the info. I looked at thier website and it seemed like they carried quite a bit of under the car exhaust, but I didn't see any from the head down to the exhaust headers. Maybe I missed it. Googled this the other day, but it looked like it was a one off project another owner was working on. In most other applications the performance increase from a set of tubular headers is usually fairly significant.

 

It looks like the image from my last post didn't show, so here is the link to that site.

http://www.leapingjaguar.com/#/exhaust/4528717789

 

ah yeah i see what you are saying.

tbh with you though, who cares. I mean do your own thing whatever, but I think if you gutted/removed cats or got one of those setups I posted the difference would be so noticeable you wouldn't care, and the difference between having that upgrade and having the actual header/manifold part on it as well wouldn't be very noticeable.

From what I have seen there isn't really a middle of the road with these cars, you have to throw down some money and really dig in to make power just because the aftermarket isn't there.
I mean you would probably have to spend over 1 thousand dollars to do the exhaust right on an XJS, and for what? Some extra power that still wouldn't put you ahead of anything else on the street you weren't before.
When some guy with a LS engine can pop 300 bucks out for a set of headers you jsut cant compete with that.
and unless you are gonna go all out and slap some turbos , a supercharger, and something else fairely extreme onto the car it just isn't worth it unless you have the pockets for it.


Id love to get a TKO 500 , bigger throttle boddies, larger exhaust, tune, upgraded intake manis for my car but it jsut wouldn't be worth it, Id have almost 10 grand in upgrades in a car as fast as a stock LS fbody.

like i said, do your own thing man but from what I have seen in my 8 months of owning a XJS the only thing worth doing is jsut trying to return it to factory and get it as nice and reliable as possible. (+wires if you don't have those hehe)

 

oh ya, i didnt look at everything on that site but i really doubt there would be room for a full set of headers without some other kind of modifications to the car. could be wrong though.

anyways if you are looking for some cheap things to release a little power try getting a local shop to straight pipe your intermediate mufflers, if your county or age allows it, get rid of the cats, cut the ends off or othewise modify the air cleaners, and get electric fans.
anything beyond that and you will never get the money returned when you go to sell and the $ to power is gonna go waaaay up

 

NOS?
I've heard electric fans are harsh on your alternator... open cone intake might be good and easy... what about light weight pulleys or even udp (under drive pulleys)? hydraulic lifters?, etc.

 

In regards to what makes sense for return on investment, your point is well taken. I guess everyone draws that line at a little different place.

 

 

 

 

Is this the type of headers you are looking for ??? Here is a link

http://www.v12sales.com/Jag-main.html

Ask for Bob Tilley

 

those are effin sick.

ROE still isnt worth it imo

 

That's just what I was think of.

Thanks

 

Does anyone know if the right side will fit an AJ16 6cyl?

 

Regarding post that 'headers don't add much'...is not true. On a V-12 XJS 5.3...if you put tube headers, free flow on back, larger injectors and something like a K&N intake you will get a HUGE increase in power. Something like 100HP on a car I recently saw. Will drop your 0-60 from mid/high 7's to low 6's.

 

dlpfrench, that's pretty interesting! Is the party a member of this site? Any chance you could have them drop in and share specifics? I bet if in addition to those mods you dropped a 4 speed tranny in there, the car would be fairly well transformed!

 

...not 100 HP. There aren't any bolt on mods that can free up that kind of power. I have those headers, a 2.5" free slowing stainless exhaust system, and tons of other mods. At best the exhaust will give you 20-35HP, but could allow other mods to be more effective. The best reason to go with a system like this is the weight savings. The next best reason is the heat soak after shut down is greatly reduced, those old cast iron manifolds sit there for hours baking all of your under hood components.
It is a huge job to install this system, but having said that, I love mine. But you won't be running around with 400HP, without major internal changes to the motor (heads w/ larger valves, larger bore pistons, etc.).

Dave

 

So this brings up an interesting question, which might deserve its own thread. What are the low-hanging fruit? The easiest, most cost-effective ways to pep up the performance of these cars?

Have you guys seen the aftermarket for Porsche 928? Superchargers, turbochargers, headers, stroker kits - you name it.

 

Lower rear end ratio, and if you are concerned about fuel economy on the highway, an overdrive auto trans, or a 5 or 6 speed conversion are your best bets for better performance. Intake and exhaust mods help too. Beyond that you are talking internal engine work, and that is serious $$.

The basics start at either building a cold air induction system, or buying a growler kit, or at the very least hacking off the trumpets on the air filter boxes, and replace them with larger diamerter pipes, coupled with K&N air filters. Then remove the center mufflers. And finally if you have the money, a complete custom free flowing exhaust system using euro downpipes, or tubular manifolds with modern performance cats (if required in your area).

Dave
1994 XJS 6.0L