Wanted.....Inlet Manifold

Hi,
I know it's a bit of a longshot, but does anyone know where I may find a Triple Carb. Inlet manifold for a GTA in the UK?

(Just the Manifold and not the full carburettor setup)

Many Thanks in advance.

Andrew.

[Alpineandy]

1) Give paul sage a call.
2)PGodfrey may well have one, but does he want to sell it at the moment?
3)Check meca parts web-site, they may well have one (I haven't looked) or they can get one. I know it's not UK, but from their delivery service you wouldn't know it.
OR maybe (probably) someone else knows something I don't.
Cheers

[stephendell]

Or find a Talbot Tagora in a scrapyard!!

Simon Auto

£795 euros + taxes

Part no. 241260

Thanks for your assistance.

So much money for so little metal !

Andrew.

Truthfully if you went to an engineering firm, with say a standard v6 inlet manifold...once they've made the weber flanges they could modify it to fit the 3 weber carbs, They could remove the top, make a large aluminuim flange the length of the manifold with the 6 ports for the carbs, and them ally weld it back together....or get a tube bending firm to make one from scratch. You could probably do it for half the cost

I originally wanted to go the easy route with IDA injection bodies on the triple carb manifold. As that isn't the most ecconomic route (so far) I'll look towards half a dozen single injection bodies a length of aluminium tube and a tig welder

Well, not just yet anyhow..

I'll keep looking for an affordable triple manifold.

Thanks again.

Bit of a problem, you cant fit programmable electronic injection to a n/a gta. The firing timing is irregular across the banks and no mappable ecu can run with this. The only way you can do it is with a late spec V6 with the even fire crank.

Ah.. Possible problem...!

I have the firing order as 1-6-3-5-2-4 (same for Z6W and Z7U engines)

My plan was to run with sequential injection fired injection and ideally distributor-less ignition (crank+speed sensor driven).

Am I missing another "feature" of these unique cars?

Thanks for any advice.

Andrew.

Its not the firing order thats the problem, but the degrees that it fires at. The even fire (z7u/w) engine fires every 60 degrees, so you can program a regular firing interval. The z6w fires at a different sequence from each bank (90 degree V6's are naturally out of balance, so they modified the cam timings front left bank to right to smooth it out. Thats why they only run carbs or mechanical fuel injection. On mappable fuel injection you can only advance or retard the firing sequence as a whole, not delay between individual firing points. The way the Z7U/W engines get round it is with the even fire crank which has offset journals and gives the correct TDC intervals. Z6W EFI can't be done im afraid! That type of engine has to be a sucker instead of a squirter!

[stephendell]

David is correct, the normally aspirated engine is odd fire. They offset the crankjournals in the turbo to make it even fire so it would run smoother and allow programmable injection.

If you look at the distributor for the Z6W you'll seen that the electrodes aren't evenly spaced so it's impossible to run aftermarket injection.

[simontaylor]

WOW, all this techno-ignition speak makes my old motor (well 18years old) sound really high tech. COOR, you guys really know your stuff. Do you learn from bitter experience, expensive experience, others mistakes' or am I missing a book from my library?

Only by finding out every technical aspect of the engine your working with, and knowing if modern day practices will work. The GTA engines are very strange in design and very hard to get real power out of...well they're not really, you just have to change everything! The most affordable and easiest way to get massive power and torque out of the Atmo is change the standard carbs for blow through versions, use a V6 Turbo intercooler in the standard position and fit a medium sized supercharger (Eaton M62 or M90). Its been done on a A310 and it made 254bhp at only 12psi. Thats nearly 100 bhp up on standard.

[Alpineandy]

I seem to remember someone telling me that the PRV engine was initially going to be a V8, but after initial designs the 70s petrol crisis made them decide to make it a V6. Rather than a complete re-design they lopped 2 cylinders off and did a partial redesign.

Maybe I was lied to

Thats right, but hardly any V engines come in 90 degree setups, Rover did one and Maserati....(oh shit..its not looking to good then!) If you want to get really technical, Ive studied papers on the torsional rigidity of the PRV V6. It appears it has an extremely high crankshaft amplitude resonance. This makes the engine very smooth across all engine ranges. Basically this is due to its 3 crank pin crankshaft, whereas other V6 engine have 6. This makes the engine amazingly balanced at very low revs, which contributes to the fact that the PRV V6's are so stable and torquey low down. Have you noticed that the engine will never knock or rattle no matter how low the revs go or if you try and stall it, and how comfortably it will sit in fifth at say 1500 revs at full load??