While most people try to find ways to increase their Vmax, I'm actually trying to do the opposite.

Without getting too much into detail about my motivations for wanting to do so, I am trying to find a way to reduce the vmax of my 3.2 AJ16 naturally aspirated engine ('96 X300) with ZF 4HP-22 automatic transmission to something that equals 4.000 engine rpm in highest gear. As the engine design won't allow me to just take the spark away like it was done way back in the times of carburettors (which I wouldn't have wanted to do anyway because it can cause some serious damage), and mechanically limiting the throttle angle (like oftentimes done on motorcycles) seems a not very elegant way to go, I am currently stuck with apparently no other option than an ECU remap, which hardly anyone is capable of. Does anyone have any ideas?

P.S.: Changing the rear axle ratio isn't an option as it is basically part of the problem.

 

Autobahnen + limited Jag

Now, seriously, there's one dude who can actually remap your ECU! And his name is Andy, he's like X300 god around here. Look up XJRengineer, send him a personal message perhaps, and he should be able to help you out And he's located here, in UK, so no US of A involved, if you'd have to send him the ECU. But there might be another option, although a bit deeper explanation behind the reason for such limit would be helpful (we do understand there must be some sort of technical issue, as you mentioned diff already).

 

Thank you! As a matter of fact, I had already previously found a post of his in one of my google searches, but couldn't contact him without being a member (one of the reasons for joining) ;-) Also, I've stumbled across Tornado Systems (they mostly do Rover V8's, but both Lucas GEMS systems are supposedly very similar), also in the UK, who are pretty sure they could help me as well.

I'd love to tell you the specifics to my "project", but first you (and everyone else) have to promise, you will not hate me for it ;-)

A year ago, I got side-swept and rearended by a VW Golf when the driver failed (miserably) to overtake me in a no-overtaking-zone. It totalled the (not very old) Golf and left the Jag with some nasty scars and a really badly damaged rear bumper. Most interestingly (and luckily) I couldn't find any obvious structual damage, so I had the car fixed as good as I could afford at the time and got it back on the road. However, the bodywork across most of the left side and below the right tail light took some serious beating and the right hand exhaust took a hit so hard it not only deformed at every bend, also a very minor crack in one of the headers got so bad I won't get around fixing it anymore. What might have happened eventually anyway, even if the accident had not happened, but pretty much started right after the accident are some major issues with the lights, mostly the turn indicators. I've already replaced the rear lighting control module with one I built myself (more about that later if you like), so I can pretty much rule that out, the body control module also appears to work just fine and it really narrows down a bit to faulty wiring - which doesn't surprise me as many of the wires I can access without taking the entire car apart show serious signs of corrosion and are in desperate need of replacement. Also, the floor board under the driver's seat needs some welding, but I really can't blame that on the Golf ;-) Oh, and none of the suspension bushings have (to the best of my knowledge) ever been replaced and now are in less-than-perfect condition...

To cut a long story short: The car in it's current state and condition won't make it past September, which is when my TÜV (equals MOT in Britain) expires, without investing a substential sum of money - which I won't even see the least bit of again once I try to sell it due to the extensive body damage it has suffered. I just can't sell it at it's current retail value, it would just break my heart, but I can't fix it either, it's just too major of an undertaking given the condition of the bodywork.

Now having two small children and, to be completely honest, never having been completely satisfied with the size of the luggage compartment, I have to admit that there have been times when an old Volvo wagon seemed pretty attractive.
However, the Jag has spoiled us so much with its smooth and powerful engine and this (then) state-of-the-art automatic transmission (not to mention the amazingly comfortable and well-crafted leather seats and that great little invention so many manufacturers still don't seem to care about called cruise control), that we had never seriously considered replacing the Jag with one of those rough-idling tractor-engine vehicles with great practicality but no comfort whatsoever. That was until I had an idea:

What if I could have a Volvo 240 wagon with an AJ16 engine and a ZF automatic transmission? What would it take to build one? Well, a Jag with good engine and trans, but bad body (check that) for starters. And a Volvo wagon that has good bodywork: I should be able to find one at a decent price after a little searching - even if that means I will have to travel to the Netherlands. ;-) The engine will be a tight fit, but it should work out if my initial rough measurements are correct. I will have to migrate much of the electronics from the Jag (luckily I need only those that currently work, not the ones that currently don't), which is a lot of work, but I rather like electrics, so that should work out as well. To make the driveshaft fit as far as I can tell having an adapter machined will do just fine. The exhaust shouldn't be too big of an issue either, I'd simply try to take as many of the original parts and make them fit the Volvo body, that should at least save me some money. I don't know yet if the Jag cooler will fit in the Volvo, and the front crossmember might interfere with the oil pan in a way that either requires to tilt the engine slightly backwards or modify the firewall a bit to move the engine a bit further back in the chassis - those are two of the things I'll have to figure out in the near future.
The part that really gave me some headaches was the top speed. I don't want it too high, otherwise I would have to do too much to the body and suspension (which I intended to keep as close to stock as possible, apart from lowering the suspension and fitting a set of polyurethane bushings). If I go for the 3.73 rear end that came with a lot of wagons, I might even be able to keep the top speed at a reasonable level, but I would really prefer to limit the engine's revs and maybe go for a longer rear end instead...

It might all sound a bit naive and youthful of me (which it may actually be), but trust me, I have given it a lot of thought (and research) and the more I get into it, the better it seems to work out. Although to my knowledge an AJ16 swap into a Volvo has never been attempted before, there have been plenty of (sometimes even more complicated) swaps, from BMW straight-sixes to Chevy and Ford Smallblock V8's. And not all by ingenious engineers with very deep pockets, many have been done by...how can I put this...a couple of drunken Swedes in a shed with parts they found lying around in a field ;-)

I am very open to all sorts of input, but please don't shitstorm me for being sacrilegeous - I'm just trying to figure out a clever and fun way to let the heart and soul of the Jag live on for a couple more years in a more practical and healthy body even after the original body has died the death way too many Jags have died before :-)

 

P.S.: that's what had happened:

 

I suspect fixing the car will be minor compared to your proposed project! The main concern I would have would be the immobiliser system, which I think your car has, but can be overcome with a non immobiliser BPM from the US. Little things like the speedometer, the gauges and warnings and the can cost you a lot of time. I believe you MIGHT have transmission problems without the ABS speed feedback, but I am not sure.
Good luck, and keep us posted.

 

The first thing that comes to mind for limiting Vmax is a rev limiter, though I don't know if one is available that will integrate with the Lucas GEMS EMS.

If your car had the electronically-controlled 4HP24 gearbox it might also be possible to limit revs only in 4th gear. Someone on this forum has discovered how to tap into the TCM to illuminate an LED representing each transmission gear, so you might be able to use a relay to connect the rev limiter in 4th gear only.

Procomp Electronics 2031 Procomp Single Stage Rev Limiters - Free Shipping on All Orders @ JEGS


If you succeed in performing the transplant, I suggest you put a Jaguar Leaper hood ornament on the Volvo wagon! :-)

Cheers,

Don

 

I love the idea of transferring the engine and the drive into different body, I was considering something of that sort myself, but that's a different story.

Another option, why not do something like this?
http://www.canevet.org/IMG/jpg/xj40-estate.jpg

 

@sparkenzap

I've checked the wiring diagrams and it appears that the ABS is designed mainly as a stand-alone-system with no interaction with any other systems (except traction control, which I don't have :-) ). Also, the Zf 4HP-22 transmission is purely hydraulic, so other than the not-in-park stuff there's no electrics :-) (if it were the 4HP-24 I believe what you said would in deed apply).
As for the immobilizer system, if I can't find anyone who deletes it from the ECU for me (at least on Rover V8s it can be done - according to Tornado Engineering - and they both run a Lucas GEMS ECU) I will have to move the entire bus system to the Volvo, thus leading the security control module and ECU to believe it was still in the Jag ;-)

Btw, does anyone know off the top of their heads what type of bus infrastructure the Jag runs? It seems to be a two-wire system and there have been rumors it's some type of CAN bus (which it actually does look a lot like from the wiring diagrams - minus the end resistors, which are not shown in the diagrams)...


@Don B

The JEGS rev limiter (as far as I've been able to read up on) only cuts the spark, which makes it universally applicable on most American performance cars (running a one-coil ignition system and no cats), but very impractical on the AJ16. You might be able to use it with individual relays to cut the signal line to the coil-on-plug system (not sure if it would work though - the entire thing might add too much resistance), but that would mean that a lot of unignited fuel would be pumped into the exhaust system where it would ignite inside the catalytic converters (over time burning them out) or even worse backfiring into the intake manifold doing all sorts of damage to various parts of the air intake system. Especially on a bivalent car with an LPG system this wouldn't be very wise ;-)
Another popular solution would be to cut the fuel supply, which might actually work whilst running on petrol, but would most likely react too slow (until fuel pressure has dropped) and then cause studdering when falling back below the rev limit (until the fuel pressure builds up again), which is also the reason why I didn't follow up on my idea of re-programming the LPG control unit to cut the LPG supply when exceeding a certain rev limit...
And another thing: please, no leaper cats on any post-Series-III-Jags (or Volvos) outside of Las Vegas :-P
Nevertheless, I am indeed tempted to leave some little hints to the Jag engine at some spots of the exterior (like the wheel hub covers for instance) - but only after all legal documentation is finished (wouldn't want to draw too much attention to what's under the hood before that ;-) )


@FireCrow

I love the idea, but it might turn out too difficult to find a coachbuilder capable of that here in Germany nowadays, and I'm pretty sure it would quadruple my build budget anyway ;-)


However, keep the ideas coming! :-D

 

In the U.S. we love our Leapers, but we don't have the same pedestrian-protection laws as the E.U. Which raises the question, why are so many European drivers hitting pedestrians?

I can recall the very moment in my life when I first fell in love with a Jaguar. I was in high school, pumping gas for spending money (the station was transitioning to self-service but still offered full-serve). A black Series II XJ6 pulled up to a pump, and the first thing I noticed was that elegant Leaper on the hood. The second thing I noticed was the lithe brunette climbing out of the car. Ever since, I suppose I've had a subconscious adolescent association between the two...

I had somehow missed the fact that your Jag runs on both petrol and LPG. Cutting the petrol supply should be possible since all six injectors share a common connection on one of their wires (I can't remember if it's the power supply line or the ground line that is common: the coils all share a common 12V line and are individually grounded by the ECM).

Cheers,

Don

 

I think your idea is a great project but is one that should only be attempted for the challenge and enjoyment of actually doing it. The end product may give you pleasure but is something that will have virtually no resale value. Set that against the the cost of a decent 10 year old Volvo estate and it is definitely a labour of love. As long as you understand that then I say Good luck with it.

(and BTW my Volvo V70 T5 engine and Auto Trans is very smooth and powerful and it has Cruise Control ).

 

I have to agree with Brendan. An inspiring project if you're able to achieve it provided you intend keeping it to enjoy indefinitely. Without having undertaken any depth of research to qualify my view, I somehow can't see the economies of scale working in your favour when compared against buying an earlier 240 station wagon (if practicality is to dictate your decision).

In the past I've owned 3 Volvo 240 wagons and 3 sedans (only 1 was new, the rest around 7-10 years old at purchase), all were reliable and supremely comfortable. As a matter of fact I have my eye on a 2007 XC70 diesel at the moment! Like the X300, they're great value and I know they are even cheaper in your neck of woods.

Best wishes with it all.

 

I had a 2001 XC70 and really liked it a lot.