LS1 exhaust manifolds

LS swapping my 1970 XJ6. Anyone know of any off-the-shelf headers that will fit with little to no fiddling? I’m using a Jaguar Specialties kit and have the Corvette manifolds that Andrew suggests, but I was hoping for a high flowing solution. It seems the only solution is to custom make headers, but I figured I would check with the hive mind.

I ls swapped my 71 xj6. I had to get custom headers made. Look for my ls swap thread, there’s pics and probably a link to the header builder.
The vette manifolds did fit and work ok

Jay, I followed your build- beautiful work and beautiful car. I’ll likely need to go the same route you did. Was the header company local? I’m in East Mesa, so I believe I’m relatively close to you.

Any tips or tricks you wish you had known before starting your swap? I’m going with an Ls1/4l60e, Holley Terminator computer and fuel cell.

i used GP Headers. had to make them myself them send out. neat bit of kit.
locally i have used 2 companies i would recommend.
RPM Headers in Mesa made custom headers for my 69 Rambler.
Cortes Performance does great custom work as well. had them modify the exhaust on the 71 jag to hug the floor better.
i used the series 3 FI fuel tanks. i considered a fuel cell, may go to that. was tempted to use a late 60’s mustang drop in style tank as well.
what is your end goal for the car?
plan to upgrade to a series 3 front subframe and xjs center section?
i’m 400hp at the wheels, it’ll go sideways whenever you want.
needs more tire/traction, can’t fit much more than a 225. :frowning:
i’m down in gilbert if you need a hand

Im sure I’ll take you up on the help offer!

My goal is for a fun sleeper that is reliable enough to go up to Havasu or other day trips. It’ll never see the track or anything too mechanically strenuous.

I already swapped in a S3 front subframe and rack. Need to flush and bleed the brakes to make sure everything still works with the different style of hoses. I have an XJS pumpkin but it’s missing parts, so I’m hoping to find a more complete one (or the missing parts). Until then I’m going to run the stock rear end.

400 to the wheels is where I’d like to be. My understanding is that the rear end becomes the limiting factor at that point.

I’m looking at running an Aeromotive cell in the spare tire well. It looks like a pretty good package. The Terminator seems like the best tuning option.

When I bought the car it had a Ford 400M/C6 combo and the wiring and plumbing was all cobbled together. Another reason for the fuel cell and Terminator, so I don’t have to rely on someone else’s hack job to work.

do you have the eng/trans?
i used most parts from a 2000 camaro ss. eng/trans/rad/etc
i used the factory ECM/TCM
sent my speedo and tach to Redline gauge works in cali to refurb and work with the gm computer/vss.

planning a 5.7?

I bought a junkyard 5.3 and 4l60. Swapped the truck intake for an LS2 intake, swapped all the front accessories to use camaro parts on truck spacing. I have a replacement camaro radiator, but I think im going to get an aftermarket one because the stock one seems like it’s really small. Summit stage 3 truck cam, circle D 3200 (I think) stall. Engine and trans are ready to go in once I verify the new brake lines I had to make are good to go.

I was going to use a mechanical cable drive adaptor for the speedo, haven’t figured out what I want to do for the tach.

not to bag on dakota digital, but i tried their speedo cable drive adapter.
it worked well at 45mph and under.
anything above and the speedo bounce wildly between 45-90.
some say that was due to the jag speedo gearing and 90 degree adapter?
i’ll make ya a good deal on my lighly used dakota adapter box lol!

sounds like a good combo. so far in the az heat the stock camaro rad holds up

Good to know, Dakota Digital was the adapter I was planning on using!

The stock radiator being adequate makes me feel better about not searching for a huge super efficient quad-pass unit.

Any issues with your hvac system? I plan to get my ac up and going after I get the car back on the road.

What cam are you running? The cam I picked doesn’t have a crazy LSA so I’m hoping it produces enough vacuum for the brakes.

If you have a lead on a posi pumpkin that’s local, I’m all ears.

This is where I’m at right now.

bought my xjs center from a jag salvage in cali.
still need to go back and get the hvac working.
you’ll need a newer GTO ac compressor
i had a custom cam made. was more concerned with drivability and power “under the curve”
custom cams aren’t much more than an off the shelf piece, and it’ll be tailored for your car, gears, tires, driving style.
looks like you have the ac drier in place!
i put a series 3 M/C in mine and notched the hood for clearance. easier and cheaper to replace, should it fail again
did you replace your hvac fans or just paint them?
dash looks to be uncracked! that’s on my list as well as getting the proper side view mirrors

I’m going to try to get the truck compressor to work. From talking to Andrew it sounds like its a space/packaging issue, so we’ll see how it turns out.

I went with the truck cam for the same reason, more torque than anything. I dont need an engine that only makes power from 5,000rpm on.

The A/C drier is from the previous engine. I figure it’s not broke, so no point in “fixing” it. Is M/C mixture control?

The fans were like that when I bought the car. I think they work but I need to fix the wiring to know for sure.

The interior is in 9/10 condition, I’m extremely lucky in that regard. Aside from removing parts of the dash to chase and route wires I’ve not had to do much to the interior. I only have the drivers side mirror, haven’t decided if I want to try to find a passenger one.

M/C i was referring to was brake master cylinder.
lemme know how the truck ac compressor works. i don’t think there’s room for the hoses or even to bolt it on?

Ah gotcha. The A/C bracket mounts pretty low on the truck block, which is the only reason I think it might work. The hoses will likely be the issue, they mount to the side whereas the GTO compressor they mount to the back (I believe).

The Dakota digital unit in my lump did not quite make the required conversion. Messing with the dip switches drove me nuts. I merely live with indicated 45 is actual 25…

I have a better way, but no longer able to get in to it again…

Sounds like I definitely want to avoid the Dakota Digital converter.

Andrew of Jaguar-specialties has a better unit to splice in at the PCM.

Caveat. It might well be me that spliced the Dakota unit in at the wrong place.