Throttle Body upgrade

[tom7]

I have recently acquired a set of PTP TB's, the original idea being that the standard fuelling equipment can be carried over from the plastic manifold.

My question is... Where does everything go?

The injectors are obvious, I assume the potentiometer fits at the end of the spindle, but what about the big hole underneath or the various air pipes or what about crankshaft breathing?

Has anybody done this conversion or can anybody with a later type SLR give some advice as to where things go. Once I know what to do I am competent enough to get on with it

Any digipics would be a great help.

Tom

 

[Bob Corb]

I am just fitting the same bodies myself. The big hole underneath (I presume you mean underneath the idle valve?) is probably where a small airfilter goes just for idle air. The crank case breathers from the cam cover should be directed into a catch tank, I've just ordered the bits form Caterham and they are at home waiting for me. The little pipes off the runners go to the ECU at one and and the fuel pressure reg at the other. If you are using an aftermarket ECU (i.e. other than mems) you will want to plug the end which goes to the ECU as its no use (very hard to get a MAP sensor working on an engine with port throttles).

 

Drop me a mail via the icon above with a no if you want any clarification/photos.

 

Bob

[tom7]

Cheers Bob,

Lucky for me someone who knows what they are doing happens to be doing the same job. The set I have are 2nd hand but unused and are allegedly complete. I intend to use an emerald for engine management.

Is it a case of once I start to remove bits from the plastic manifold, it may become obvious where they go, but I will email you for photos when I get home tonight.

Do you know if is it possible to vent the crank case breathers (I understand one of them can now be blocked off) back into the manifold in some way, through the backplate or into the filter? A catch tank seems such an incomplete solution somehow.

It looks as if the throttle cable bracket on my set may be incomplete, so if you have a photo of that it would be useful.

 

Many thanks

Tom

[Peter Carmichael]

Oil fumes from the breathers can cause detonation if they are fed into the intake - does that sound like a complete solution to you? Good for emissions, but lousy for engines.

 

A catch tank is a better option.

[tom7]

Thanks Peter,

I'll take good advice and sort out a catch tank.

But...how or why does the standard Rover plenum setup and most modern engines breathe into the intake without problems. - Not a challenge, just a quest for knowledge.

 

Tom

[Bob Corb]

The std rover engine doesn't rev as high as the Caterham (fastest is 7200 on a VVC) and the sump is much bigger which prevents the oil from bouncing off the crankshaft into so many little droplets. Its the small droplets that detonate mainly and these are usually caught by the gauze in the cam cover before they go too far.

 

A Caterham engine mounted in the wrong direction (front -rear ) with a shallow sump revving into the stratosphere whilst producing more lots power (190 BHP at 7800 for the VHPD) means that there is a lot more gas being vented and lots of oil vapour/droplets being carried with it - not good news.

 

The bits should carry across fairly easily but I'll send you some more photos of my older style manifold fully dressed soonish.

 

Cheers

 

BC