Timing on a TVR 4.5 BV V8

Timing on a TVR 4.5 BV V8

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gsx600

Original Poster:

2,740 posts

255 months

Thursday 12th August 2004
quotequote all
Guys, hoping someone teccie can help me ?

I have a 4.5 BV that I have slowly been installing into my 400se Wedge, and have a quick question about it

What is the best timing point to start from ?

It also has a larger plenum, jag injectors, jag airflow meter, lower enlarged trumpers, but at present standard 4.5 ecu, so should kick out a few healthy bhp's once everythings sorted - very noisy with no manifolds !

I have a tool now to set tdc correctly to start off with and mark pulleys etc and was thinking about dialing in 8 btdc on the gun but seem to think 4 btdc has been mentioned on a forum somewhere

Also another question about fueling I currently have an adjustable fuel regulator plumbed into sytem Webber FSE type, what sort of pressure should I set this up to at idle as again heard rumours of 3 bar although set to just over 2 bar at mo

Cheers


>>> Edited by gsx600 on Thursday 12th August 12:06 to say regulator not pump !

>>> Edited by gsx600 on Friday 13th August 13:40

350matt

3,766 posts

286 months

Thursday 12th August 2004
quotequote all
8 ° BTDC at idle with the vacuum advance discconnected is a good start ( you can reconnect the vacuum when you've set the timing)
Fuel pressure as std rover SD1 is 30 -33Psi (2-2.25Bar) although this is very variable

Matt

350zwelgje

1,820 posts

268 months

Thursday 12th August 2004
quotequote all
Fuel pressure is standard 36 psi. In the wedge bible a fuel pressure of 39-40 psi is mentioned as a good setup. But the pump must be able to deliver more during acceleration. And a stall pressure test should see at least 45 psi. And bigger capacity, larger injectors: you need the pump to able to maintain the pressure when a lot of fuel is converted into power, otherwise you will start to be running lean and the engine could be damaged (pinking).

Rob

steve_D

13,795 posts

265 months

Thursday 12th August 2004
quotequote all
You should not try and control the pressure using the pump.
Set the pump to max and fit a quality variable pressure regulator on the return from the fuel rail to the tank. This is adjustable for the basic 35 psi already mentioned but is connected to manifold vacuum and varies that pressure dependant on load.

Steve