All major fabrication and powdercoating/painting is done. Now working through test fitting and terminating ECU wiring and fuel/hydraulic/brake lines (tedious) and bolting stuff back in for the final time (fun!).
Got the 8-stack on and roughly sync'd up today. It's a speedmaster unit which was cheap, and I've replaced several parts and some design to make sure throttle actuation is the way I want it. Basic casting and throttle bodies are pretty good.
Shortly I'll be powering up the Holley ECU and checking all systems and sensors. I won't be able to test fire until I complete the hydraulic systems, which include a hydro-boost under the floor.
Completed the EFI systems check and loaded in my best guess tune, tested and flushed the fuel system, and generally tidied up and completed most of the wiring. Apart from a dud TPS everything was fine.
Took the car off the stands for the first time since we gutted it of its old powertrain and cut the front off it to see how it looked with the chosen wheel and tyre combo, and to check ride height. Front is good, rear a bit low (just resting on the bump stops), so will be adjusting springs to gain 50mm at the back for a slight rake. The wheels will take the factory hub-caps and I'm happy with the way rear wheel arches look "full".
What was not so good is that while doing a rough string line wheel alignment it became obvious I have one and possibly two bent lower rear control arms in the jag IRS - I have 2mm toe out on one side and about 6mm(!) on the other. The parts I bought second hand came in a subframe that had some other damage too - I should have checked those parts out more thoroughly. I will get it on a computer alignment machine and then pull it apart and use a press to tweak them good.
First start will be after xmas once I get a new tailshaft seal in the TKO600, fit the driveshaft, and put oil in motor and box. We are off to Wanaka tomorrow for xmas holidays, so have a good one and all!
Steady progress has been made in the man cave on the 6/90. Front sheet-metal went back on pretty well - a major relief given that we cut the front of the car off at the firewall and rebuilt the chassis forward from there for the LS and the Jag IFS at the start of the build. Was able to modify and re-use the original bumper irons. All the wiring is done and I installed Lucas H4 halogen retrofit headlights while I was at it.
Met with the upholstery guy and interior is scheduled in for April - mainly carpet, kick panels and door seals - rest is pretty good.
Some fairly major embarrassment when I realised I had classic SBC/BBC firing order loaded into the Holley ECU instead of LS - no wonder the first few start-ups were rough in the post above - poor bloody thing was only running on 4 pots!
I've got the idle and idle control roughly tuned and I'm on a pretty steep learning curve as I'm using Alpha-N (TPS based) fueling coupled with a set-up pretty sensitive to very small throttle openings. It's pretty obvious that the native strategy for the Holley is speed density - there are some hard-wired defaults that are not ideal for Alpha-N - I hope it learns properly in Alpha-N.
Once we complete the skid plate to protect the under-floor hydro-boost unit, we'll bleed brakes, steering, and I'll start roading tuning under load.
After a lot of faffing around we got brakes and clutch bled, and the hydraulic system (which includes power steering and underfloor hydro-boost brakes) bled, and then got ready to hit the road for the first time.
Clutch is pretty heavy (OEM single disk LS7 Vette) but takes up not far from the floor so no opportunity to lighten it with a smaller bore master, and I think weight is mainly due to the fairly low pedal ratio we have with the stock floor mounted pedals. I can live with it.
Brake pedal is firm and short, requires more shove than a modern car, but on the flip side is not touchy and over-assisted, which I hate. Even with the much higher power assistance from the hydro-boost this is down to the huge 1.4 inch bore GM 2500HD master cylinder I'm using (came with the hydro-boost) whereas the original Jag master to match the 4-wheel discs on the car was 1 inch bore. Also, the pedal ratio is also fairly low like the clutch. Overall it feels about "right" given the weight of the clutch, and pedal height and weight are good for heel and toe action. And the brakes work.
Steering is thumb and fore-finger light as you would expect from an XJ Jag power rack and a 17 inch steering wheel! But it is direct, precise with no slop, and has a fair bit of feel. Gear change is nice with mechanical feeling long throws which suit the character of the car.
First drive was cut short by front wheel to guard interference. I knew that was coming but I thought I'd be able to sneak in a few open road runs on the motorway to coarse tune the fuel map before I dealt with it. Unfortunately the springs settled about 40mm with all the front bolted on and it was basically eating the front tyres on the slightest bump or turn. The cammed LS3 is as docile as a brick with the 8-stack and feels like it will not disappoint.
I managed to get enough ECU datalogging in to point me in the right direction and validate that all key systems and functions are either already good, or have potential to be good.
Car is now back up in the air as Hamish works his magic on the front guards (seen here with the eyebrows removed and the wheel jacked up onto the bump stop) and I've whipped the rack out to have it reconditioned (I'd punted on a second-hand unit but it was leaking from the powerhead top pinion seal - bugger). We are lifting the front end 1.5 inches from what you see here, which will give the car even "eyebrow" height front and rear, and a slight rake courtesy of the taller rear tyres.
That is a true sleeper. It realy looks like a sheep while its just a monster. No one will believe the four tailpipes Nobody will ever understand what just happened when you floor it and show your taillights for a second before you'll disapear at warpspeed into the horizon.
Still making incremental progress, but still waiting for final front guard lip mods to be completed for certification.
Have the car pretty much 95% tuned and running well. The 8-stack is incredibly fussy to tune at very low throttle angles where small changes create large percentage changes in airflow, but got it mostly nailed. At wide open it runs well, solid from idle, good to 4k where it comes fully alive and pulls hard to my self imposed current limit of 6800.
To kill the time while waiting for body work, I have had the interior done and replaced door seals etc. It's come up well and as it is lined with dynamat it has delivered a substantial increase in interior refinement.
I have also had to build a second set-up for the rear of the exhaust system as the quad tip twin flowmasters are too droney and loud (even though they sound excellent under power) and the position of the tips was causing fume ingress into the boot. I have magnaflow mufflers in the mark 2 version with curved S-type tips towards the outside like an original XJ Jag.
Hi JP, yes I have two resonators about a metre back from the header collectors - possibly too early in the system but the only place I had room - and even with the resonators in place the flowmasters are over the top. I made a mistake above - I actually fitted a pair of Dynomax Super Turbo 17734 Exhaust Muffler in their place not Magnaflows.