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(this is a reposting- put up again due to some confusion with the forums- now resolved)
Hi all, as a follow up to a conversation we were having last month, I want to let you know about a couple of very interesting XJS- LS conversions that a couple of our customers are doing. The text and pics below are excerpts from our recent New Year update Email and I hope you enjoy them. And please feel free to Email or PM for questions or for more info (or post here....)
And to answer a question that came up before, these sort of installations are compatible with RHD. As a matter of fact, about 25% of our Jag-LS customers are actually from Australia and/pr New Zealand..... So if you're a right hooker, and LS powered Jag is an option.
This is actually a "reconversion"- the car was converted years ago with a 1995 Caprice LT1 engine (not using our kit/parts) and had an engine fire due to poorly installed fuel lines. The customer loves the car so the damage you see will be repaired and a new GM LS3 ERod is going in. For those not familiar, ERod is a special engine package GM offers that is emissions legal in California for all 1995 and earlier vehicles. Oh and by the way, it makes 430hp so this should be a really fun car.... Stay tuned for updates.....
A side sight- 1990 XJS after eng bay fire- a poor quality LT1 conversion some 10 years ago led to this. But a new LS3 Erod will make the owner smile again....
This project is being done by a shop in Arizona for an owner who loves this very unusual XJS (besides being one of the hand built Hess and Eisenhardt convertibles, it also has a TWR body kit and other nice upgrades). These 2010 and up Camaro LS engines (called L99 and displacing 6.2L) make 400hp from the factory, which for most if us is plenty. But the owner actually wanted a bit more and a popular upgrade for them is a cam/lifters/springs package from Texas Speed, which will ultimately make some 470 hp or so when done. And keep in mind this XJS will also be losing some 350 lbs of engine weight-wow. As of this writing the car had just been fired up. Here are some pics…
These later generation LS packages are getting more reasonably priced now so we’ll be seeing more of them going into Jags, making for some very fun cars....
87 XJS Hess and Eisenhardt convertible with TWR kit.... Sharp!
Camaro L99 6.2L and 6L80E transmission- as delivered
I like the V12 and certainly would not replace it just because. But if the V12 was not repairable, an LS conversion with OD transmission would be very tempting. Maybe with a turbo or two.
And that's the case on both cars here- they both had major V12 engine problems that pushed the owners into something else for power. Here in California, rebuilding a V12 can easily hit $20k all told, and neither owner wanted to go back down that road with their car. So a conversion was the new direction. For these models, the LS engine are so much better than any previous conversion options, with a huge range of displacements, power outputs, and a gigantic aftermarket support base. Anyway, I wanted to post a few updates on these projects for you to see
1990 XJS getting an LS3 Erod- the older LT1 with fire damage was removed along with the transmission and other conversion related parts. Due to damage to the ABS system's wiring, the car will be switched over to an 88 style (pre-ABS) standard master cylinder/booster setup for reliability. That was unfortunate as the Teves ABS is a good system but too much of a risk in this situation. As far as the rest of the engine compartment, it cleaned up very nicely including the fenderwell paint which was stull nice an shiny underneath the grime. Installation of the LS3 wiring harness has begun and you can see the fuse panel there in the right rear of the engine compartment. The engine itself will go into the car in a few weeks so stay tuned. (did you notice the Superformance Cobra Daytona coupe in the background....??)
1987 XJS H&E Convertible/ L99/LS3- As I mentioned in an earlier post, this car is pretty far along and is about ready to fire up. Next stop is the exhaust shop. Here are some pics of the nearly finished install just as a barrier is to be added around the air filter to only take in cool air. Notice the amount of space between the water pump and the radiator- that will be a big help for cooling air flow. And a nice shot of the car back together.
Andrew, enjoyed reading about your latest find. I say stay with the LS conversion since that is what you know so well. Maybe throw a super charger or something different on it. Some nice headers and a custom exhaust will make it sound sweet. How much weight are you able to shave off going with a LS over the V12?
So in general, as you can imagine, the weight savings on an XJS going from V12 to LS is substantial. For the cars with an auto trans, we are seeing some 350 or so lbs almost entirely off the front end. When my 88 XJSC with LS1 and 6 speed manual was finished we put it on the scales and it came in 400+ lbs lighter than the V12 cars. That was actually a little surprising but we weighed it twice (on an official California emissions dyno scale) to verify. I had not expected the manual vs automatic trans difference to be that much. Regardless, that level of weight savings (approximately 10% of the car's original weight) makes for huge changes in handling dynamics and feel. When I first got it, my 88 was a running/driving low miles car with the V12 so I got a chance to drive it that way for a while. Then, months later, it was on the road again with an LT1 and 6 speed manual (probably a 300 lb reduction) and I was amazed how different the car was with no other changes.
Just to give you a little update, the red XJS convert in this thread is now moving forward again. A 430hp LS3 GM Erod engine (100% emissions legal in California for any 1995 and earlier car) is in house as is a brand new GM 4L65E ( 4 speed auto overdrive) transmission. These are going in as we speak. Interestingly, GM never offered the LS3 with a 4 speed automatic from the factory, but GM performance offers that combo as a "Connect-and-Cruise" package that is basically everything you need in one box to get on the road. The shop owner and I talked a bit about going instead for a 6L80E trans (6 speed auto with 2 overdrive gears), but for this car (and this 85 year old customer) we figured the added complexity, weight, and cost, weren't worth it. And with the stock 2.88 ratio diff, the last thing the car needs really is a deeper overdrive. I'll have some pics of the package as it goes in shortly... here it is just out of the box as arrived...... (Does that look like 430 hp?)
We'll be following the build as it goes over the next month so stay tuned
Andrew, enjoyed reading about your latest find. I say stay with the LS conversion since that is what you know so well. Maybe throw a super charger or something different on it. Some nice headers and a custom exhaust will make it sound sweet. How much weight are you able to shave off going with a LS over the V12?
01-31-2020, 05:45 PM
Interesting XJS-LS Conversions- in the works.....
