Discussion
OK just playing with an idea here. Having recently seen the "reborn" MGB's running Mazda MX5 engines and countless swaps over the years got me thinking. I have a Jaguar XJC and it currently has a 6.0 XJS v12 in it (but annoyingly not the one with the four speed box).
My question is.... how do you work out what engine swap would actually fit the car? Say if I wanted to fit a 3.0 Diesel engine and 8 speed box out of an XF or the V8 supercharged XFR engine. How would I go about it to even make a start assuming I could lay my hands on an engine.
This is just hypothetical at the moment as the car is in for restoration.
Enlighten me....
My question is.... how do you work out what engine swap would actually fit the car? Say if I wanted to fit a 3.0 Diesel engine and 8 speed box out of an XF or the V8 supercharged XFR engine. How would I go about it to even make a start assuming I could lay my hands on an engine.
This is just hypothetical at the moment as the car is in for restoration.
Enlighten me....
The easiest one is to find out what swaps other people have done/how tight the fit and then get the dimensions for those engines. You can then get dimensions for other engines and compare to get an idea of how easy things will be.
If there's room for a V12 in there at the moment length probably won't be limiting, nor will width if you drop to an inline. Height is offer the killer with classics because modern engines need to be really tall for some reason.
Unless you're doing something common where enough people have trodden the path that someone's made parts you will hit issues and have to engineer around them, but that's part of the fun.
If there's room for a V12 in there at the moment length probably won't be limiting, nor will width if you drop to an inline. Height is offer the killer with classics because modern engines need to be really tall for some reason.
Unless you're doing something common where enough people have trodden the path that someone's made parts you will hit issues and have to engineer around them, but that's part of the fun.
//j17 said:
Height is offer the killer with classics because modern engines need to be really tall for some reason.
Unless you're doing something common where enough people have trodden the path that someone's made parts you will hit issues and have to engineer around them, but that's part of the fun.
Yeah height was the issue I thought it would come up against. Most of the cars that have had swaps away from the original engines are in the states so they have LS3 Chevy V8s in them Unless you're doing something common where enough people have trodden the path that someone's made parts you will hit issues and have to engineer around them, but that's part of the fun.
craigjm said:
Yeah height was the issue I thought it would come up against. Most of the cars that have had swaps away from the original engines are in the states so they have LS3 Chevy V8s in them
Also be aware of width if going for a V6/8/whatever. A modern dual overhead cam vee engine is much fatter than one with a single cam in the block running both sets of valves with pushrods. That's one of the advantages of the LS series, being very compact.I have multiple engine swap t shirts.
An MGA 1500, I took an 1800 from an MGB, same block, rebuilt the bottom end and ported a head, fitted a 5 speed Ford box and a taller diff. We did the actual swap over of all the stuff over one weekend. All dead simple.
A Porsche 911, 1978 SC 3.0ltr, had thrown a rod, I rebuilt the 3.0 and put it back on the road, then I bought a 3.6ltr from a 993 vario ram with loom and ECU and all the ancillaries, fitted that with a new uprated clutch, the ECU went under the passenger seat, just like in a 993. Was a bit more complex and fairly costly, but it went like f
k!
The measuring up is easy, you need to keep the crank/gearbox output shaft/prop all co-axial otherwise the rotor dynamics will be shot to st, more loss in the joints and likely more vibration.
On V engines exhaust manifolds can be a bear and there's 2 to sort out.
Later engines and boxes require more sensors and wiring and sometimes chip work.
Its always doable, there's some crazy st out there, the Merlin SD1 and the JAG XK MG Midget, its just a question of how hard it is.
I've also done 2 twin engine motorboats and I'm defo not doing another! fk that!
An MGA 1500, I took an 1800 from an MGB, same block, rebuilt the bottom end and ported a head, fitted a 5 speed Ford box and a taller diff. We did the actual swap over of all the stuff over one weekend. All dead simple.
A Porsche 911, 1978 SC 3.0ltr, had thrown a rod, I rebuilt the 3.0 and put it back on the road, then I bought a 3.6ltr from a 993 vario ram with loom and ECU and all the ancillaries, fitted that with a new uprated clutch, the ECU went under the passenger seat, just like in a 993. Was a bit more complex and fairly costly, but it went like f
k!The measuring up is easy, you need to keep the crank/gearbox output shaft/prop all co-axial otherwise the rotor dynamics will be shot to s
t, more loss in the joints and likely more vibration.On V engines exhaust manifolds can be a bear and there's 2 to sort out.
Later engines and boxes require more sensors and wiring and sometimes chip work.
Its always doable, there's some crazy s
t out there, the Merlin SD1 and the JAG XK MG Midget, its just a question of how hard it is.I've also done 2 twin engine motorboats and I'm defo not doing another! f
k that!finishing touch said:
"OK just playing with an idea here. Having recently seen the "reborn" MGB's running Mazda MX5 engines and countless swaps over the years got me thinking."
Shirley people don't spoil an MX5 engine by wrapping an MGB around it do they ?
http://www.frontlinedevelopments.com/vehicle/mg-le50/Shirley people don't spoil an MX5 engine by wrapping an MGB around it do they ?
Huntsman said:
The measuring up is easy, you need to keep the crank/gearbox output shaft/prop all co-axial otherwise the rotor dynamics will be shot to st, more loss in the joints and likely more vibration.
Odd that you should say that. I thought that a lot of older cars had misalignment deliberately designed in to avoid the splines and CV joints sitting in one position. A hot rod builder once quoted that he used half an inch, front to rear.t, more loss in the joints and likely more vibration.
craigjm said:
I don't want a manual box. I could do that easily but I want to keep it auto but if just upgrading the gearbox then the late v12's 4 speeder is the only way, apparently.
The 6.0 from the late XJS or the XJ81 uses a GM 4L80e gearbox. Found in lots of Chevy trucks and things. It's by no means the only way, but it is probably an easy way, as you can use factory bits to bolt it together.I suspect it wouldn't be beyond the realm of possibility that the current 6 speed paddle shift auto found in other GM cars like the VXR8 might also mate up pretty easily.
I assume your 6.0 is a TWR XJR-S engine?
To answer your question about engine swaps. In general most things can be done. But require 4 things:
-Money
-Time
-Inclination
-More money
If you are doing the work yourself and you are capable with the right tools (I'm guessing less likely, as you probably wouldn't have posted this thread). Then it'll be a lot of work.
If you are paying someone, then it'll be a lot of work still. But even more money.
The physical fitting of the engine is only part of it. Fitting of the transmission is equally as important. Both may require surgery to the vehicle and re-design.
Modern units are also heavily ECU dependant. So you'll need to overcome these issues.
If you are not matching an engine to a gearbox that it normally uses, then that's more work too.
And then there are all the wiring and plumbing issues. Cooling, coolant hoses, where the exhaust will go, induction and so on.
It can certainly be done and there are entire industries that specialise in doing so. But if you are doing it on your own on a rarer car, or less modded one. You'll have to R&D so much more, as there will be so few 'bolt in' options.
And at the end of it, you might result in ruining the character of the car and it's resale value. So it's something worth considering very well before hand.
Cheers 300bhp that is pretty much my thought
I am sure the GM box can fit and there are adaptor plates available. Have had an initial quote of 2k for a gearbox and fitting. This would give it some improved oomph off the line and a quieter and slightly more economical cruise at motorway speeds.
The later 6 speed GM boxes are physically bigger so would require some hacking of the car I guess
The most popular engine swap for these cars and other series 1-3 seems to be Americans replacing the engine with a 6.2 LS3 Chevy v8 and the aforementioned GM four speed box.
I am sure the GM box can fit and there are adaptor plates available. Have had an initial quote of 2k for a gearbox and fitting. This would give it some improved oomph off the line and a quieter and slightly more economical cruise at motorway speeds.
The later 6 speed GM boxes are physically bigger so would require some hacking of the car I guess
The most popular engine swap for these cars and other series 1-3 seems to be Americans replacing the engine with a 6.2 LS3 Chevy v8 and the aforementioned GM four speed box.
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