Background:
I bought this 1998 XJR 124k off of eBay just before Corona hit. Price was right. I wanted another XJR to drive to allow my other garage queen XJR to keep her miles low.
It's spent its entire life in North Carolina so body and undeside is awesome . It was advertized as needing tensioners. Running, but noisey chains.

It's only cosmetic flaws are sun faded paint on roof , deck lid and hood. It's hardly noticeable with a polish and ten foot pole .
. Even the headliner is tight. No such luck on cupholder. Its tweaked No surprises there.

. It sounded great on startup but after full temp it slowly started chain rattling. Upon teardown it had the predictable upper tensioner cracks started in the plastic and cracks in the chain guides .
. However the actual failure point was a LOWER tensioner that collapsed and seized in closed position as if pin was installed . This allowed scary amounts of primary chain slack on one bank.

I could have just done the chain kit and go driving until some else breaks but that's just not me.
At 124k I wanted a fresh Cat

So.......
Currently engine is completely reassembled
( finally ! ) and awaiting one last upper hose and idler pulley before I put the radiator and fans in for first start up.

I wanted to do some performance mods on this one . Aside from ramping up the supercharger with reworked pulleys and adding extra charge cooling and of course the mandatory K&N air filter I found limited performance info on these engines . Not none, just limited.
I decided to return to basics of my 40 years in the business.
. I reworked the heads with as much porting and polishing as allowable and valve job and seals.
I did my best to port and match exhaust manifolds with heads as well as intake side.

I also ported and polished and matched up supercharger intake and TB elbow. The elbow is the biggest restriction in the whole intake system.
I relieved its thin casting as much as possible and polished out the inside for optimal flow. It's also port matched with Throttle Body .
. All this with new hoses all around , new head bolts and eurospare gaskets . Etc...The exhaust manifolds were blasted and recoated with 1000 degree F cast coating.

Finally I spent countless ridiculous hours hand and wheel polishing all engine parts that came off or could be reached while disassembled.
I polished parts where the sun never shines and no one will ever know how clean it is but me. Also nook and cranny detailing under the hood almost done.
Hey I had some extra Corona time to fill.

OK way more than enough for now.
let you know how she runs when next ebay delivery arrives.
Here's some pics coming

Almost done.




Just delivered.

to anyone remotely interested.
Ronn

 

That turned out really nice! Great color too!

Did you take pictures of all the PNP you did on the insides of the engine components? I’d really like to see that.

Which style of head gaskets did you go with? MLS or the stock fiber type?

 

I took pictures of internal work on another device and am having trouble getting them uploaded to my PC. I'm sure I'll get them up.

 

Nice work!

 

Thanks Brandon.
Just another XJR . I just happen to really like them. I wish I could afford one in every color.

The thought was that this one would be my regular driver so my other two Jags could be Sunday summer cars. But the body is so clean on this one too that I hate to put it through NE Ohio weather and terrible roads. Let alone the normal scuffs and scrapes from parking lots etc.

. I think I need a well used higher mileage x308 with just enough road rash and wear and tear that I feel no guilt daily driving it knowing it will never be garage queen condition again .
. Something that I can keep road worthy but not feel I need to " restore" or hand polish every time I drive it and get it dirty.
. I think I am trying to justify yet another Jaguar. ?
Gotta go , switching to classified forums.

 

All gaskets were stock type from Eurospare w New stock head bolts, not studded.
. Hopefully that will suffice. We will see when I turn up the boost. I'm only doing a lower pulley not upper (not both). I think I will upgrade the coolant pump and charge cooler though for good measure.
. Save that for next order.

 

UPDATE : To anyone remotely interested. lol

So I finally got all the little engine details done and finally fired up the engine today to test all my new work.
I only ever drove this car 1 mile from my shop where it was delivered from North Carolina
to my home garage before I tore it down so I wasn't sure what else to expect.

The good news : Engine fired right up and went right to smooth idle , no lights. No leaks, no surprises.
Drove a little subdued at first but as soon as I was confident the temp was steady etc...
I gave her a couple good romps on the pedal and she performed like new with full
power pulling forever ,.Turned the traction control off for a second to have a little fun.

Both rear tires lit up evenly in a straight line (?) and it was only excessive tire smoke , speed limits,
and good common sense that I let off and did not destroy a new set of Tires . lol

The Bad : I cant really complain, a totally unknown car . everything worked great with one exception.
The shocks are all weak but.......the right rear is totally non functional along with noisey mounts .
I'll take it ! Any comments on best price/ source Bilsteins?/

Will try to post a few relevant pics shortly. Best to all Ronn

 

North Carolina sun burnt hood paint after 8 hours of restorative polishing. Some blems just wont come out below clear coat but amazed compared to what I started with.

After first test drive . She came home on her own power ( and lots of it ,lol). Notice roof fade , hood was same before 8 hours restorative polishing.

before . see earlier above for post assembly pic .


So the tablet I used to take my internal and porting work has crashed after multiple attempts to upload picturs to my PC.
A dated samsung android device.
Aside from a few cool engine pics I may have also lost a few thousand of my kids .
Some are backed up but ..??? who knows currently at my PC doc for salvage work.
Will see what he says.

The head porting was nothing fancy just what you would expect. It did polish nice .

However its the TB elbow and SC intake port matching that I wish I could show.
The TB elbow is super thin cast but also the weak link in flow.
Time will tell if it cracks on me but I was able to relieve a lot of obtrusive material
and improve volume aprox 10 % . ( as per sealing off one end and filling to brim with water / before vs after )
Crude but effective measurement for estimating volume .

Not sure where I stand with power enhancement yet. This XJR was bone stock original.
I can only compare to my 99 XJR buts its got some minor mods too. So not sure what stock feels like.

 

Nice update!

Glad to hear the engine's good when you were done. I can’t hardly stand wrenching on my engine 8 hours much less 8 hours on restoring the hood. Makes me cringe thinking how long your going to spend on the roof!


Too bad about the PNP photos. I would’ve really liked to have seen those.

Good lookin ride!

 

Yea it's a long time to spend on one panel. !

The sides are like brand new all around
but that NC sun is brutal on the flat surfaces.

I will ultimately repaint the top surfaces but for now one more 8 hour marathon on the roof and she's ready to cruise the rest of summer. I'll have to put some shocks and bushings asap but at least the
rest of front end is tight.

. For all those who have had a long project come to fruition you understand my excitement at now just driving the darn thing every chance I get.

 

Final update.

I was able to get a few short test drives in last week. All good as was the first.
No leaks , squeaks, warning lights or other frights.

Today I went for a real test drive
freeway, on ramps, full throttle accell. Etc.

I have to say now that this 98 XJR is significantly
quicker than my 99 XJR you can feel how well it breathes and how fast it spools up when you floor it .
. Much snappier , not that the 99 xjr is any slouch.

In fact I can tell it's on the " edge" meaning the
rear diff or prop shaft or wheel studs etc are now vulnerable to sudden failure upon full torque input.
. Its a scary beast . Very pleased so far.

Hopefully will get an accurate 0 to 60 time run or maybe a run for fun at our local dragway.
Best to all . Catch you on another thread.



.

 

That's what I like to hear. Sorry if I missed it. What pulley(s) for boost did you change?

 

I only upgraded the lower pulley. (Powerhouse)($$$)
I am using my own expanded charge cooler loop made out of 5/8 coiled copper tubing out front of the original cooler as a supplement instead of the almost 1k for oversize unit from PH.
Some copper tubing , a few 5/8 elbow hoses and zip ties and that's it. So far so good.

. I also plan to upgrade the electric cooler pump with the Mercedes unit but for now running stock circ pump with extra homemade cooling loop.

I think the combination of relieving all the intake passagways to the cylinders as well as exhaust ports , charger ports and TBI elbow and expanding the breathability has a cumulative effect with the faster charger speed.
. My thought is that you can force cram all the air into it you want with higher boost OR you can make it breath as well as possible first. Then the extra charger speed and increased airflow through the charger is maximized.

Just got done driving again today.
It really is a beast. It broke traction on the upshift at around 70mph at full throttle and caused an ultra brief traction control event . Lol

. I'm sure there are plenty faster XJR s out there
( especially you crazy nitrous guys , lol)
But I wouldnt want this one any faster. I'm good for a minute.
.

 

Yeah, that PH lower pulley is something else isn’t it?

You might find that a 12” fan mounted in front of the supercharger radiator will do even better with the charge air temps.

 

I was thinking the same thing. Putting an aux fan .
. I also took extra time to make sure my cooler grids are all extra squeaky clean.

 

Drove my Black 99 XJR ( 53k) today to compare to my fresh Red 98 XJR build.
the 99 has factory cold air intake , big exhaust. All internals stock.

Conclusion......... Its not my imagination.

The new 98 XJR build is night and day faster than the
99 XJR. Strictly seat of the pants , Nothing scientific yet.

The 99 launches , accelerates, and shifts great like it should,
but.....
the fresh 98 build difference is that you feel it launch, accelerate
and shift soooo hard and fast you're just sure somethings going to break soon.... lol

Can't imagine what it would do if I added the undersized upper pulley also.

Anyone out there running both upper and lower pulleys with cooling mods?

Think we're going to go to test and tune day at the track soon for some real data .

 

I know you have the PH lower pulley on your 98’ but, on your 99’, you may want to test the secondary fuel pump to make sure it’s still working.

On my 98’, I have stock pulleys, but on my 03’ Super V8, I have a PH upper 1.5 lb pulley and I have a lower 09’ XFR factory harmonic balancer. On the XFR pulleys, circumference of both pulleys are a bit bigger. I only drove the 03’ once with the new pulleys and it seemed good but I need to build an intake and have the X pipe installed. The previous owner had a true dual exhaust added along with some aftermarket rear mufflers. It sounds good at idle but sounds like an old Chevy pickup with a 350 and cherry bombs on it. That X pipe needs installed and getting rid of the ‘modified’ stock air box in order for me to see how much better it’ll feel.

 

My 02 xjr 100 is stock performance wise. Just the Mina intake tube and BMC air filter, stock air box. Car definitely is a bit more responsive and a little more S/C whine. So yeah, tube is definitely worth changing.

OP, if your diff dies, I would put a quaife lsd in it.

 

Does a CEL light come up if the secondary fuel pump is failing/failed or does it not register?

 

I was wondering myself. You would think a failed secondary pump would eventually flag some kind of code . If nothing else a lean code under WOT, or something?

Good news is that for a few more weeks of summer our nearby raceway has a street night on Wednesday evenings.
I am hoping to get an opportunity to run both of my XJRs for 1/8th mile time trials before season ends.

. We will see what my seat of the pants analysis really adds up to in actual performance numbers .
.
I don't think my black 99 xjr is suffering any failures like boost pump . But ??? We will see at the track.

It's rated zero to 60 in 5.0 seconds and it seems like it's well in that zone if not a tenth or 2 better per amateur stopwatch runs
It's just that now....
The newly modified 98 red one just seems noticeably quicker , as I said on the verge of breakage at WOT. The 98 runs on 18s and the 99 on 19s. Not sure if overall tire circumference differences amount to effective gear ratio difference but I might measure just for amusement.

I'll post something when I get some real data.