Petrol Injection Queries on my TR5

[Big Hop]

Hi Folks

 

I am rather new to both the TR forum and TR ownership, I have a newly purchased TR5.

 

I wondered wether anyone with a lot more experience in these matters may be able to help me with the following;

 

 

It is a TR5 with according to the history file and invoices that came with the car it has a Classic Racecraft engine fitted (different cam etc..), running on the standard PI set up.

 

1) It smells very rich at all times

 

2) It deposits sooty marks over the rear of the car (doesn't really bother me this bit, but is this normal)

 

3) When sitting at traffic lights on tickover for a while it seems to choke itself up as when you accelerate off it is really lumpy, sounds terrible and is a right pig, although if you keep reving it (and make yourself look like a boy racer) it then goes off fine and dandy....

 

4) It starts with no choke at all, nearly allways 1st time.

 

5) It goes like a bomb at high revs but just doesnt like driving at low speeds / revs.

 

 

Are they all connected, is there a problem? are some of the above expected? is there any recommendations to improve its running, infact any advice on these matters would be greatfully received.

 

I await your help.......

 

Thanks in anticipation Chris.

[Alec Pringle]

Hi Chris,

 

 

Classic Racecraft - that will be Jon Wood.

 

A fine engineer, he can build a damn good engine, but his engines are generally built for speed rather than comfort.

OK, some are more ferocious than others, but generally they're built for go, not show.

 

It's probably not the best idea in the world to let someone who isn't familiar with Jon's engines play with it. It may already have been tinkered with ! Far better to let Jon himself set it up on a rolling road, after which it will doubtless go like the proverbial bandit . . .

 

Cheers,

 

Alec

[88V8]

1) It smells very rich at all times

 

2) It deposits sooty marks over the rear of the car (doesn't really bother me this bit, but is this normal)

 

3) When sitting at traffic lights on tickover for a while it seems to choke itself up as when you accelerate off it is really lumpy, sounds terrible and is a right pig, although if you keep reving it (and make yourself look like a boy racer) it then goes off fine and dandy....

 

4) It starts with no choke at all, nearly always 1st time.

 

5) It goes like a bomb at high revs but just doesnt like driving at low speeds / revs.

 

Are they all connected, is there a problem? are some of the above expected? is there any recommendations to improve its running, infact any advice on these matters would be greatfully received.

Hello Chris and welcome

Before I forget, it will be easier to use the forum if you click on the Options box in the right side of the blue bar at the head of this topic, and alter the View mode to Standard.

 

As I'm sure you suspect, it's running too rich.

If the PI system is over 15,000 miles old, could be wear & tear on the metering unit. As they wear, they run richer.

What spark plugs are you using and what colour are they?

 

Wear of the metering unit (usually known as the M/U) can be accelerated if the pump pressure is too high or the pressure relief valve is wrongly set.

Otherwise, it's likely not set up properly to suit the engine.

 

To set up the unit needs deep knowledge and a flow rig.

Would be worth speaking to a specialist such as Malcolm at Prestige.

http://www.prestigeinjection.net/

He will get you on the right road.

 

Just a tip for the future - you will get more response on injection queries if you post in the TR6 forum, cos that's where most of the PI cars live. Same goes for queries in general on the 6-pot motor and drive train, although you should always mention it's in a TR5.

 

Ivor

Edited December 9, 2008 by 88V8

[88V8]

Forgot last night: two things you could look at...

 

There's a vacuum hose from the top of the M/U to the throttle bodies, usually to the centre body. This is crucial in mixture control. Check that it's sound, and firmly attached both ends.

 

Second, on top of the M/U there's a lever which is operated by the 'choke' control. When the control is closed, the lever needs to be against its stop.

 

Worth a look.

 

Ivor

[Big Hop]

Thankyou for your advice. I will keep you posted.

 

Chris.