Buying tips for a V-8 converted XJ
 

Hello all,

First post here, but I have been reading and lurking pretty hard ;)

I have read the normal buyers guides on the XJ, but any specific advice when looking at a Chevrolet engine converted V-8? Like what kit and special considerations on radiator or transmission?

The one I plan to see is a '74 XJ6L with a 305 TH350 setup. But the seller claims great for DIYer, so IDK what he is getting at just yet... More to come I suppose.

Eventually no matter what I would like to have an LSx converted Series 2/3. Mated to a TH400 or 6l65E depending on year. If FI then keep it that way with electronic trans. If carb then keep it that way plus a TH400.

I'm still a little worried on headroom as I am 6'4" but again that is too be seen as well.

The look of these cars is just classic and I need a good sedan for the long term... Sadly the modern lines don't do it for me.

Also I am no stranger to wrenches so getting dirty is no biggie. Hopefully I can navigate the snafus of Lucas electronics! LOL

My father used to own a new XKE V-12 convertible back in his twenties and loved it... But ended up selling it as the maintenance costs were crippling... It would be interesting to keep his old picture posing with his XKE next to a modern with an XJ6!


Thank you!

Headroom may indeed be a problem for you. I'm 5'9" with 34" inseam and have no trouble getting into my 1976 Xj6L Series II.

My husband is 5'11" but with all his height in his torso (30" inseam) he can't sit upright in my Jaguar or his head hits the roof. He has to have his seat not only as far back as possible but also the back must be a couple notches toward Recline for him to sit comfortably.

These cars aren't as bad as some new jelly-bean cars made to transport the "vertically challenged" but they were built for *average* adults of 40 years ago.

I suggest you find one and actually sit in it before you look farther into buying one regardless what the engine/trans might be. Then if you can fold yourself up into the driver seat without heroic effort, imagine numerous folding/unfolding repeated during a couple hours' time. If you're good with that, the Xj6L might be OK for you.
(';')

I'm 6' 2"and quite comfortable, not a great help I guess as its only those final inches that matter. My 6' 6" son will be passenger-ing for the first time on the weekend, I will report back. As Elinor says its probably as much to do with body type as absolute height.

Only comment on your plans is that I would think about the T700 trans. nice mix of gearing for acceleration + overdrive. You may find the T400 makes the car rev a bit much on the freeway depending on the diff ratio. May not be an issue depending on how you use the car.

Really the main enemy is rust, lower window corners and floor pans mainly it seems. We dont have as much of an issue here but perhaps some of the guys from places with a real winter could comment.

Good luck with your project

If the engine and transmission has been done properly, (and as an Englishman, I can't tell you anything about V8 "lumping"), then as Yarpos says, rust is the big enemy, plus electrics due to their age. The electrics were fairly shaky even when new, and the ageing process causes electrical connections to corrode and cause other problems. Most suspension and brake stuff is easily obtainable. The brakes are superb, but the rear brakes are inboard and a PITA to attend to so they tend to get neglected.

Try to find out if the vendor who lumped it, had the rear subframe out of the car to refurbish it. Front suspension is an easy fix with ball joints an easy swap if worn.

V8 xj6
 

As I am in the middle of installing a 350 V8 in my 86 Xj6 I feel I could can write a book on this subject. So many variables exist from one guy's idea of a nicely done transplant, to the next guy's 'good enough" attitude and the resulting gremlins that will take the fun out of it.
When I work on any of the various systems, (fuel injection , electrical start circuits, run circuits, cooling, how the Jag body wiring is grafted to the GM electrical circuits etc.) I think to myself its a good idea to keep a log with photos that documents how the work was done and why. Wire colors / what injection system / smog stuff / in general how the swap was done. Does speedo work. So the more you know about successful (everything works including the TCC) swaps, especially the Jag to GM V8 swap the better off you will be. If you can get a "map" of the wiring and how if now differs from stock - that would be a plus. Is the VSS connected? Is the P/N functional? Where is ECM ...as I said so many variables. I guess your common sense and mechanical ability will be best assets. Lots of great stuff in the " LUMPS" archives

305 and TH350 imply a carb'd car. Not complex at all. The electric grafting fairly simple that way. If a 3.331 to 1 rear ratio, the V8 will be happier with it than the original 4.2!!!
If a 2.88 rear, the 305 will have the torque, sorta, to pull it.


Five paths to lumping, that I know of. Each unique to itelf and fitting for each to choose.


1. John's Cars in Dallas
2. Andrew Weinberg's Jaguar-Specialties in the San Jose, CA area.
3. JTR in the Livermore, CA
4. Another outfit, whose name I can't recall, and gone anyway in the LA, Ca area.
5. Home done, in total.


Some very neat, others oh,oh!!!


Alyn, not quite a book, but a white paper. "Lump Thoughts", by me. Lost in cyberspace, though!!! If I can find that little floppy that might have it.....


I forgot which is which. But, the SIII either has more or less head room than the SI and II predecessors.


The moon/sunroof of the SII does take up critical head room.


I've shrunken from barely 6'0"" to 5'11. I like the seat well reclined. I fit just fine.
My dear departed was a tall gal. She fit nicely as well.


Agree. The rust thing is the most important. Rust and icebergs share a commonality.


The electrics can be problematical, but manageable. Some easier than others.


And whatever path was taken. Caveat, the original Jaguar radiator is not up to the task.....


Carl

Thank you very much for the feedback!

I have not heard back from the owner yet over phone. Just a few emails. More to come!

Question: Where did the term "Lump" "Lumper" come from? LOL

Thanks!

Just to complete the height feedback promised earlier, my 6' 7" son seems to fits OK up front with an inch or two clearance.

Some people take Lump as a derogatory or put down term used by purists, refering to the rather agricultural early small block chevy compared with the OHC Jag 6 or 12. Conjures up the idea of a weight penalty for the V8 when its actually the reverse. For some LUMP is an acronym for Less Upkeep More Power. I dont have anything to compare to, but I do find keeping mine alive reasonably simple and low cost. I think on here LUMP is just a common term to refer to a converted Jag without any particular inference really.

When the XK engine was a 3.4 it was a very robust and reliable engine. Problem was Jaguar modified it to 4.2 litres and from that point on, the reliability and quality dropped off, especially when the long-stud engines were introduced. These are a PITA and never really sorted out with the slotted block from about 1981 onwards. Meanwhile the US makers got very skilled in making thin-wall iron block V8s that are far better engines for normal use. The best engine Jaguar ever made was probably the AJ6 and AJ16 straight sixes. These go on almost forever.

LUMP = Less Upkeep, More Power


Cheers
DD

I like that :)

That gives me hope!
Otherwise I thought I heard mention of a slider modification that gave a few more inches.
FWIW I am a square... 6'4" 36 inseam 36 sleeve 36 waist... Not sure if that is what Jaguar designed for :)

I have yet to hear back from the seller this week... But more to come. Even if this one falls through, there are plenty clean in the NoVA (DMV) area.

Thanks!!!

Seller vanished... But still has the CL ad up. Ack, i'll just keep looking!

Thanks for all the insight!