Discussion
One thing I noticed when I did both of my engine swaps is that the bigger the age cap between car and intended engine, its gets more complex.
Say you wanted to put an AJ16 in a series 3 XJ6 it would be easy. But try and put a supercharged V8 from an XJR into a Mk2 and its a great deal Trickier!
Say you wanted to put an AJ16 in a series 3 XJ6 it would be easy. But try and put a supercharged V8 from an XJR into a Mk2 and its a great deal Trickier!
craigjm said:
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.
Indeed, there are a number of Jag specialists in the USA offering complete 'all you need in a box' fitting kits to do just that.....(only snag is they will be designed for LHD cars, so not all the bits might fit a RHD car?)I've toyed with doing this two two separate cars.
First one was a Triumph Spitfire. This died on the vine because, although quite simple from an engineering perspective, more power from a K Series or VTEC would have exposed all the other shortcomings (bendy chassis, silly rear suspension design, etc). I looked at adding independent rear suspension and bracing the chassis, but by this point projected spend was moving past 10k, and I'd still have a car that was inherently compromised. Engine height was also an issue, so I'd have had a lower sump and higher bonnet line to cope with.
I've recently been toying with a Mercedes C126 SEC, but single-figure mpg for +/- 200bhp offends my sensibilities. I could cope with that sort of fuel consumption if I had 500bhp to make the rear tires spin, but not for less power than a modern 2 litre engine. This led me to either the 5.5 or 6.3 AMG n/a units. Advice from a couple of Mercedes specialists was that it would cost a small fortune to engineer, and I'd need to upgrade every other part of the driveline and brakes to cope. Projected spend moving towards 20k with lots of talk of 'contingencies'.
Ultimately, I've concluded that the idiosyncrasies of these old cars is part of what makes them special, whether it's geared to do 5000rpm in top at 80mph, has a 5.6 litre engine producing 226bhp, or can't pass a petrol station without popping in to say hello. It's all part of the fun!
First one was a Triumph Spitfire. This died on the vine because, although quite simple from an engineering perspective, more power from a K Series or VTEC would have exposed all the other shortcomings (bendy chassis, silly rear suspension design, etc). I looked at adding independent rear suspension and bracing the chassis, but by this point projected spend was moving past 10k, and I'd still have a car that was inherently compromised. Engine height was also an issue, so I'd have had a lower sump and higher bonnet line to cope with.
I've recently been toying with a Mercedes C126 SEC, but single-figure mpg for +/- 200bhp offends my sensibilities. I could cope with that sort of fuel consumption if I had 500bhp to make the rear tires spin, but not for less power than a modern 2 litre engine. This led me to either the 5.5 or 6.3 AMG n/a units. Advice from a couple of Mercedes specialists was that it would cost a small fortune to engineer, and I'd need to upgrade every other part of the driveline and brakes to cope. Projected spend moving towards 20k with lots of talk of 'contingencies'.
Ultimately, I've concluded that the idiosyncrasies of these old cars is part of what makes them special, whether it's geared to do 5000rpm in top at 80mph, has a 5.6 litre engine producing 226bhp, or can't pass a petrol station without popping in to say hello. It's all part of the fun!
a big part of the 'cost' estimate is who you plan to do the work and what sort of engines you are considering.
If your AMG engine is going to set you back £8-12k to start with, then yes it'll be a pricey project. If however your donor engine might be £500-1500, then it's a rather different ball game.
In the case of the op, if all they want is different gearing, there are lots of potential answers. Such as an OD/slitter unit. It attaches to the output of the gearbox and before the prop (short prop needed) and allows you to split the gears. So could turn that old 3 speed auto into something with affectively 6 gears.
If your AMG engine is going to set you back £8-12k to start with, then yes it'll be a pricey project. If however your donor engine might be £500-1500, then it's a rather different ball game.
In the case of the op, if all they want is different gearing, there are lots of potential answers. Such as an OD/slitter unit. It attaches to the output of the gearbox and before the prop (short prop needed) and allows you to split the gears. So could turn that old 3 speed auto into something with affectively 6 gears.
300bhp/ton said:
In the case of the op, if all they want is different gearing, there are lots of potential answers. Such as an OD/slitter unit. It attaches to the output of the gearbox and before the prop (short prop needed) and allows you to split the gears. So could turn that old 3 speed auto into something with affectively 6 gears.
Tell me more / point me in the right direction please 300bhp/ton said:
There are a number of US companies, I'll try and dig some links out, but struggled to find them in my bookmarks earlier. Lots of the hot road, custom, retro and pro-touring scene use them.
These chaps?https://www.gearvendors.com/
bucksmanuk said:
These chaps?
https://www.gearvendors.com/
Thanks, yes. Think I've seen someone else doing something similar too, but can't find the bookmark for it.https://www.gearvendors.com/
Op - I think this kit would work:
https://www.gearvendors.com/hrgm3s.html
Mostly. But you'd probably need your prop cut down or a custom one made (lots of Land Rover specialist could probably do this for you).
Cost wise I suspect similar to a 4L80e conversion. Maybe a little cheaper.
You might need to mess about with a different final drive ratio to get the sweet spot. Not sure how easy it is to change these days, I know when I had my XJ-S V12, there were a couple of options of final drive from different places.
How funny that this is here as i just posted something similar in the Jag forum last night. I'm an expat Brit in the US and have been fascinated with the multitude of LS swap options out there, especially with the tuner guys and now the younger guys hitting the oldtimer classics. It just doesn't seem right putting a LS int a Jag though. BUT, given the old V12s from the early 90s have the 4l80e trans, what about a Bentley/RR 6&3/4 to mate up? I get the ECU concerns, but on sheer size would the 6.75 and its cooling fit into the XJS bay? I'm just daydreaming.
Kieron75 said:
How funny that this is here as i just posted something similar in the Jag forum last night. I'm an expat Brit in the US and have been fascinated with the multitude of LS swap options out there, especially with the tuner guys and now the younger guys hitting the oldtimer classics. It just doesn't seem right putting a LS int a Jag though. BUT, given the old V12s from the early 90s have the 4l80e trans, what about a Bentley/RR 6&3/4 to mate up? I get the ECU concerns, but on sheer size would the 6.75 and its cooling fit into the XJS bay? I'm just daydreaming.
I can see that being costly....I get the LS swaps in the US. It's just so cheap and easy. LS engines are plentiful and easy to find. Reliable, easy to tune and upgrade and lots of bolt on bits.
You can buy a self learning EFI setup for them too. So it really is plug and play, making installs very easy.
That said, if you already have a Jag V12, then why not tune it for more poke? It might not be the last word in peak power. But it's more than upto the task of providing plenty more shove.
I've also done a number of engine swaps in my time too and the best advice I can give anyone that's going to do it is "follow in someone elses footprints that's already done that conversion". Contact them to find out as much about how they've done it and what the pitfalls and downside are. Then you can make an informed decision on whether or not to do it. I've been a trail blazer a number of times in the past with engine conversions/swaps and it can be an expensive and complicated path to take, especially now with more modern engines with ECU and car management systems in.
I now convert cars to electric as it's a hell of a lot simpler from the mechanical point of view, simply a conversion plate to bolt the motor to the bellhousing (more difficult if it's transverse). Then all the complexity is in the programming of the controller and wiring in of the battery/charger system. Still it's no walk in the park but the instant delivery of torque when you first put your foot down is always worth it.
Here's a pic of a conversion I've just done on a Beetle
I now convert cars to electric as it's a hell of a lot simpler from the mechanical point of view, simply a conversion plate to bolt the motor to the bellhousing (more difficult if it's transverse). Then all the complexity is in the programming of the controller and wiring in of the battery/charger system. Still it's no walk in the park but the instant delivery of torque when you first put your foot down is always worth it.
Here's a pic of a conversion I've just done on a Beetle
Edited by electric_fanatic on Tuesday 2nd August 17:10
electric_fanatic said:
I've also done a number of engine swaps in my time too and the best advice I can give anyone that's going to do it is "follow in someone elses footprints that's already done that conversion". Contact them to find out as much about how they've done it and what the pitfalls and downside are. Then you can make an informed decision on whether or not to do it. I've been a trail blazer a number of times in the past with engine conversions/swaps and it can be an expensive and complicated path to take, especially now with more modern engines with ECU and car management systems in.
I now convert cars to electric as it's a hell of a lot simpler from the mechanical point of view, simply a conversion plate to bolt the motor to the bellhousing (more difficult if it's transverse). Then all the complexity is in the programming of the controller and wiring in of the battery/charger system. Still it's no walk in the park but the instant delivery of torque when you first put your foot down is always worth it.
Here's a pic of a conversion I've just done on a Beetle
Nice work, never even thought about electric conversions for classics!I now convert cars to electric as it's a hell of a lot simpler from the mechanical point of view, simply a conversion plate to bolt the motor to the bellhousing (more difficult if it's transverse). Then all the complexity is in the programming of the controller and wiring in of the battery/charger system. Still it's no walk in the park but the instant delivery of torque when you first put your foot down is always worth it.
Here's a pic of a conversion I've just done on a Beetle
Edited by electric_fanatic on Tuesday 2nd August 17:10
Edited by Rsdop on Tuesday 2nd August 19:35
Gassing Station | Classic Cars and Yesterday's Heroes | Top of Page | What's New | My Stuff