No Snap Crackle or pop !

[badredwedge]

I love my 400 hotwire but I do miss the crackle and pop of the old 350 on the over run.
What prevents a hot wire from making these fantastic noises??.
Is there anything I can do ??


sits back waits for sarcastic responses

[brummiewedge]

Leave the exhaust manifolds loose, and you can have that authentic shed at lights sound too!

[waynester]

My '90 400SE pops and bangs fine. That mean i'm a flapper?

[']['![]V[] W]

Could be that your 350 was being overfueled too much. whereas the 400 isnt.... Every car is dif

>> Edited by ']['![]V[] W on Friday 10th February 11:57

[jmorgan]

Me too also on a hotwire. I live with it but love it it when I follow a flapper. Someone will be along shortly with the technical.

[wedg1e]

In a word: progress. The hotwire system includes 'proper' control of the fuelling on over-run. On the flap system, the ecu still sees the trigger pulses from the ignition amp; the air demand of the engine keeps the airflow meter flap lifted and the ecu pretty much ignores the throttle pot and keeps chucking fuel in.
Range Rovers added a vacuum-controlled switch that disconnects the ignition amp signal so the ecu thinks the engine has stopped and turns off the fuel. I guess this serves two purposes: first it makes the Rangey sound a bit more refined (think of the target market) and second it probably gives increased engine braking, ideal when towing. Whether that mod was ever used by TVR on the flap system I don't know, but I suspect not
Some Wedges do have the two white wires that would normally go to the vac switch on a Rangey: they dangle around at the rear of the engine, if yours is one of them.

[badredwedge]

' said:

['![]V[] W]Could be that your 350 was being overfueled too much. whereas the 400 isnt.... Every car is dif

Correct Tim every car is different a 350 (and most other Wedges) have a Flapper and alot of 400s have Hotwire. The key word her being Hotwire.

[']['![]V[] W]

whats flapper, whats hotwire?:S is flapper a carb, n hotwire an ecu?

[number 7]

The air metering system: a flapper has a flap moved by the incoming air and translated into a signal for the ECU. Crude but effective, and also a physical restriction to breathing. Hot wire is a more sophisticated air metering system using a heated wire to calculate the air mass by the cooling effect that it produces. Virtually no physical restriction to flow.

7.

[badredwedge]

wedg1e said:

Some Wedges do have the two white wires that would normally go to the vac switch on a Rangey: they dangle around at the rear of the engine, if yours is one of them.

I dont know I will have to have a look. so I am looking for 2 white wires doin nothin ?
If I find them what dif will that make ?
Thanks Wedg1e.

[wedg1e]

badredwedge said:

wedg1e said: Some Wedges do have the two white wires that would normally go to the vac switch on a Rangey: they dangle around at the rear of the engine, if yours is one of them. I dont know I will have to have a look. so I am looking for 2 white wires doin nothin ? If I find them what dif will that make ? Thanks Wedg1e.

No point looking if you have a hotwire, they won't be there!

[firefox1712]

A hotwire - isn't that what you call a thermocouple?

[badredwedge]

wedg1e said:

No point looking if you have a hotwire, they won't be there!

So is that it Wedg1e ? am I doomed to a life of silent over run ?

[badredwedge]

firefox1712 said:

A hotwire - isn't that what you call a thermocouple?

NO NO NO .........Thats a gas fire / cooker / boiler

[wedg1e]

badredwedge said:

wedg1e said: No point looking if you have a hotwire, they won't be there! So is that it Wedg1e ? am I doomed to a life of silent over run ?

Unless you put a spare injector in one of the downpipes, fired from a .... NO! Don't do it!

[badredwedge]

wedg1e said:

badredwedge said: wedg1e said: No point looking if you have a hotwire, they won't be there! So is that it Wedg1e ? am I doomed to a life of silent over run ? Unless you put a spare injector in one of the downpipes, fired from a .... NO! Don't do it!

So thats all I have to do .. get some optimax down the headers . Cant be that hard

[adam quantrill]

Try disconnecting the wire from the speedo sensor thing. I've heard that it cuts the fuelling while the car is moving so there is less fuel there on the overrun. If the ECU thinks the car is stationary it might fuel a bit more. Also I agree with loosening the front exhaust clamps a litle.

[rev-erend]

V8 Racing quoted earlier that a leaking exaust header would cause
plenty of popping and banging - personally I'm not sure why this would cause that effect

Not sure how allowing air into the exhaust would allow unburnt fuel through.. but if he says it works - I believe him.

My hotwire SEAC also does not pop and bang..

[badredwedge]

adam quantrill said:

Try disconnecting the wire from the speedo sensor thing. I've heard that it cuts the fuelling while the car is moving so there is less fuel there on the overrun. If the ECU thinks the car is stationary it might fuel a bit more. Also I agree with loosening the front exhaust clamps a litle.

Yep I thought about that, I thought I might take the little wheel thing out from inside the speedo sensor as unplugging it cuts the circuit, with the circuit intact but no wheel to register movement maybe this may fool the ECU into thinking its stood still ??



>> Edited by badredwedge on Saturday 11th February 08:20

[badredwedge]

brummiewedge said:

Leave the exhaust manifolds loose, and you can have that authentic shed at lights sound too!

Not sure I want it to sound like a 1956 Fordson Major