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navigator16078

New Member

• Jul 30, 2011

• #1

HELLO

my 3.5 which is in a 164k 1993 disco auto box does not seam to have much power,towed a caravan with it yesterday it was pretty guttless ,its on lpg also any idears why please.

 

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jailon

Active Member

• Jul 30, 2011

• #2

suggest a good service to start (engine and gearbox) with but i remember reading somewhere that in high milers the camshaft lobes wear slightly so the valves dont open and close as much as they should do.

would suggest a dyno to check out how much bhp you are kicking out, remember auto boxes do cause more loss on "at the wheel BHP" than manuals..... only problem is I dont know anywhere that does 4x4 dyno's ???

 

vougese39

Well-Known Member

• Jul 30, 2011

• #3

Let's start with the basics poor timing worn disssy faulty vac unit,running constantly of gas with do more harm than good, plugs leads cap and rotor ram gen items.
Efi faults duff Afm, worn out engine try a comp test properly cam rolling road is expensive way to find out any v8 over 70 k will have a worn cam so at 160 + will be fubar

 

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navigator16078

New Member

• Jul 31, 2011

• #4

Ok thanks

 

zen

Well-Known Member

Events Planner

• Aug 7, 2011

• #5

and then there is the fact that they have f all power when good!

 

jamesmartin

Well-Known Member

• Aug 7, 2011

• #6

low compression v8s are pointless i always fit h/c pistons when rebuilding them,much better

 

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deano67

New Member

• Aug 15, 2011

• #7

do you have a manual adjuster on the gas line from the vapourisor to the mixer ? if so this may be restricting gas flow at high rpm therefore restricting power, if it revs ok at 3000 rpm in neutral it should be ok if not open it up a bit until it does rev ok :car:

 

norseman

Well-Known Member

• Aug 19, 2011

• #8

jailon said:

only problem is I dont know anywhere that does 4x4 dyno's ???

Click to expand...

They do exist but be wary of using them. Your '93 will have a VCU & if it's starting to show even the slightest symptoms of 'locking up' you risk transmission damage during an extended test. Also when I had my last RRC tested a while back the operator said that the print-out figures for power/torque were not reliable for auto's(!) which seemed strange to me as once the converter locks up the car is in direct drive.

 

crazydave

Member

• Aug 21, 2011

• #9

Forgive me if I sound like an idiot, but surely a rolling road is basically driving/thrashing your car in a straight line? As I understand it, the VCU is only there to allow for the front prop turning a little faster than the rear prop when cornering? Therefore even if it was seized solid, driving in a straight line would be fine, indefinately?

I'll apologise now in case I'm wrong.

 

norseman

Well-Known Member

• Aug 21, 2011

• #10

crazydave said:

Therefore even if it was seized solid, driving in a straight line would be fine, indefinately?
I'll apologise now in case I'm wrong.[/quote

I'm sure others will answer this one, but I can only go by my own experience. A few minutes into the high-speed test there was a loud 'bang' from the front of the RR & the test was terminated, though by that time the machine had achieved the desired results. As I reversed the car off the rollers & out of the building there was an audible 'clonk' from the offside front wheel every complete revolution & this was repeated when driving forwards. Having performed a number of slow speed circles & reverses on the car park I drove home slowly & upon arrival the noise had stopped, never to return, but I always wondered what had caused the scare & vowed never to repeat the exercise - though my current RRC is sans VC (230T 'box) so would probably be ok to test(?)

Click to expand...

 

vougese39

Well-Known Member

• Aug 21, 2011

• #11

The disco was never fitted with the Borge warner transfere box.
You can easily say the fault will be a tired engine in need of a bit of tlc a cam and a top end rebuild for starters