Thread: Questions re 4L to 4.6L and more...

Originally Posted by banarcus

Hmmm maybe I have made a potential break through in the Discovery 2 and P38 "repowering your V8 world"? The only other inputs that I can see are the transfer case low range, fuel tank and level inputs, and the CAN bus lines for diagnostics etc.

In an imaginary world, right now one could buy a alloy LS1 motor and matching 4 speed with GM PCM to control both. Buy the adapters for the GM auto to LR transfer case, engine mounts etc. Assuming the LS1 runs a return line for the EFI, run a return line back to the disco's fuel tank. That leaves me with the future upgrades of the diffs, driveshafts and axles. One would then ask, why did I buy my disco for in the first place???

My brain is hurting right now

My assumption on the ACE is that it would get a speed signal at the very least. The ABS/TC/HDC is all driven from the Wabco modulator and control unit which would also have its own speed sensor too. I wouldn't know if the ZF box control unit interfaces with either of these though. More research.

**Oh and another thing I should fix is that HDC is controlled by the engine management system.

You can change the transmission in the Becm on a D2 to manual, the engine ECU and trans will be standalone, very achievable I think

Also you'll need to use a 4L80e which is far more costly, but these are the only mass produced adaptor, also you'll need to shift transfer case and make new shafts

Originally Posted by TerryO

Hey Pedro,

Long time no speak...

The whole idea of repowering any vehicle with a larger engine is to get more power which logic would say means you need / want more power for your particular driving application. So the question needs to be asked has anyone actually driven a 5.0L to see how good they actually go compared to a 4.6L or even a 4.0L?

Sometimes extra cubes doesn't always mean that much extra powerwise. I have been in vehicles with low spec Chevy 454's fitted that felt much slower then similar vehicles with healthy 327's fitted.

One thing I have learned the hard way is claimed increased HP outputs by people selling go fast gear in many cases means bugger all.

cheers,
Terry

Stock holden or ford 5l in a rover still is a much more pleasant drive than any N/A rover 4.6 I've ever been in

Originally Posted by clubagreenie

Just having another think. ABS/HDC/TC all run off wabco.

HDC only runs in Low Range. Switch inputs to where? Possibly same as the (Black/Blue?) wire from the CDL wire under the dash. May also input to ECU to retard for batter engine braking.

TC/ABS runs from the braking system ecu and needs inputs from speed sensors, and possibly g'box to tell it when it's in HDC.

ACE needs speed input (only ops above 20k's by memory) plus the accelerometer (either 2D fore/aft / L/R or Pitch/Yaw/Roll) but there's no body sensors to relate body position to suspension level so it must level from the accelerometer.

The auto at least must use some speed sensoring as (at least on mine post rebuild) you can notice it self down shifts when slowing down.

I had another look and for automatics, the EMS obtains two speed signals from different sensors. One is from the SLABS and the other is from the auto gearbox itself via CAN data bus which makes integration even harder.

Regarding my earlier comments on the 4.6L tune in existing EMS', I've re-read rave and this is what it says:

"A single ECM is used for the control of the existing 4.0 litre engine and the new 4.6 litre engine introduced with 03 model year vehicles for the NAS market only. The ECM contains the tunes for both engines variants. When the ECM is replaced, TestBook/T4 must be used to select the correct tune to match the engine fitment."

It's not really clear either way for vehicles here in Australia. Perhaps someone with testbook or similar would be able to confirm this?

If there was a way of hacking into the Motronic like others have on BMWs and Audis, you could change simple things like firing order, fuel injector slopes, ignition maps etc to suit a new donor motor because simply put, it would be a major pain to try and integrate Ford, GM or whatever with the Bosch system and everything else in the vehicle. More research later.

So to get the 4.6 tune we need a post '03 ECU? Possibly NAS spec as well since they only get the 4.6?

Has anyone done or priced getting an existing 4 litre recoed with new liners and cam, pistons, litters, good valves and springs etc with some aggressive porting and polishing and a full balance including the flywheel harmonic balancer itself? This would make a noticeable difference to throttle rEsponse and go at a reasonable price. Cheers

I can get CNC port mapping/grinding/finishing done but thats more that most would want to spend on an entire rebuild. Going to that extent you might as well get a stroker kit and top hat liners. But just inlet work and cam (and I'd go roller cam/lifters/rockers) is feasable but depending on which inlet you start with, you don't want to change too much.

Surely $1000 or so would buy you some decent clean up time on a bench at a machine shop for both heads...porting and polish and perhaps taking the dags of the manifolds where they meet..and make a big difference to throttle response. It does not have to be port matched just cleaned up.

Cheers

Originally Posted by clintox

Clubgreenie your not wrong there very interesting, who in Perth has one of these testbooks to tune mine. It runs excellent and like wise on fuel very happy.

Pretty sure Marc at Beechboro 4X4 has Testbook