P38A Tuning the 4.0 thor

[marjon]

Why not just fit a 4.6, instant tune up .
Oh and a gearbox.

J

 

[marjon]

Sorry the tornado chip is EPROM, but that doesn't say what the original chip is

The Tornado chip is still locked, so you cant change things and get the info as far as I know.
You change the chipset and thats it.

J

 

[norseman]

Why not just fit a 4.6, instant tune up .
Oh and a gearbox.

J

To quote our transatlantic friends .. there 'aint no substitute for 'cubes.

 

[marjon]

To quote our transatlantic friends .. there 'aint no substitute for 'cubes.

I guess that’s why I also own a 6.3
And would agree
Until I get to the petrol station

J

 

[kermit_rr]

To quote our transatlantic friends .. there 'aint no substitute for 'cubes.

Beef stock, or vegan

 

[LR-hobbs]

Just to add to this, if the engine is on 122000 do the basics before anything like ECU mods, i.e. Replace main & big end bearings, piston rings, etc. Clean up & relap the valves. Look at a mild tune cam (which should not require ECU mods). Also check & replace the hydraulic lifters, although this depends on condition. You will probably also need rocker shims depending on the camshaft. After all that make damn sure the water pump & radiator are in good condition & replace if there's any doubt.

You may be quite surprised how much more get up & go it has.

Then depending on what camshaft you chose, remapping the ECU might (big might) be worth doing, but it really depends what type of driver you are.

[EDIT] As an example when I bought my blue 1998 P38 4.0 GEMS 125k miles as a project it was running badly, although it started reliably. Somewhat slow compared to my Green 4.6 GEMS. After rebuilding the 4.0 engine with all standard parts, it's now significantly quicker than the 4.6 with no need for tuning !!

Both radiators air con and coolant got replaced under my ownership so there brand new.

Shimming the rockers is something I am trying to wrap my head around , I don't understand how you check the hydraulic lifter clearance or how big of a shim to add.

 

[pwood999]

You could search the forum or google it. It’s been described many times by peeps changing cams, lifters or doing head skim.

 

[LR-hobbs]

You could search the forum or google it. It’s been described many times by peeps changing or doing head skim.

Fair enough

Cheers

 

[pwood999]

Essentially it’s getting the preload on the lifters correct. If it’s wrong it impact compression & engine won’t be at its best.

 

[LR-hobbs]

Essentially it’s getting the preload on the lifters correct. If it’s wrong it impact compression & engine won’t be at its best.

Which I imagen with a torque cam , it's almost definitely going to need shimming. I may try to contact a local specialist closer to the time , to see wether I could get them to come out and check for me.

 

[DanClarke]

Good job my MY 2000 P38 is approaching 25,000 miles.
It finally feels like it is "loosening up" quite nicely.
Most problems are due to the rubber elements breaking down and failing.
I am perfectly happy with the performance and see no need for any chips (except with battered fish). ;-)

 

[pwood999]

Which I imagen with a torque cam , it's almost definitely going to need shimming. I may try to contact a local specialist closer to the time , to see wether I could get them to come out and check for me.

Depends on the Cam profile, but yes does need checking & doing. It's whether the heel of the cam is same or lower than the standard that matters. All the guides I have seen requires the tappets to be empty of oil & the gap about 40 thou with the cam on the valve close position.

http://www.v8wizard.com/camshafts_Setting_Tappet_Preload.php

 

[LR-hobbs]

Depends on the Cam profile, but yes does need checking & doing. It's whether the heel of the cam is same or lower than the standard that matters. All the guides I have seen requires the tappets to be empty of oil & the gap about 40 thou with the cam on the valve close position.

http://www.v8wizard.com/camshafts_Setting_Tappet_Preload.php

With all things considered I am tempted to see what my local specialist would charge to do the cam for me, while this will be expensive it's cheaper than a new engine or car.

Being new to working on engines this isn't something I want to get wrong , it's my daily car and only car.

 

[brianp38dse]

Quote
(it's my daily car and only car.)
brave man most of us have a back up motor or two

 

[Datatek]

Quote
(it's my daily car and only car.)
brave man most of us have a back up motor or two

+1 ^^^^^^^^

 

[Rubberknees]

+1 ^^^^^^^^

+2^^^^^^

 

[LR-hobbs]

Quote
(it's my daily car and only car.)
brave man most of us have a back up motor or two

Does it make me more brave that it's a 4.0 that I daily drive to work and isn't on LPG ?

 

[kermit_rr]

Does it make me more brave that it's a 4.0 that I daily drive to work and isn't on LPG ?

No. If lpg isn't exactly right (hard to do on a modern log system on an old efi car) you can end up with very hot combustion temps.
Brave that it's your only wheels. Been there done that

 

[LR-hobbs]

No. If lpg isn't exactly right (hard to do on a modern log system on an old efi car) you can end up with very hot combustion temps.
Brave that it's your only wheels. Been there done that

I have heard lpg can ruin engines due to the gunk , similar to what comes out of a forklift.

 

[kermit_rr]

I have heard lpg can ruin engines due to the gunk , similar to what comes out of a forklift.

Not sure what gunk comes out of a forklift, but lpg burns very clean. Perhaps it's residue from additives some engines need for lubrication, the rv8 will happily run on neat lpg