Thread: Pulsed air injection

Originally Posted by wlb

Can anyone please tell me when pulsed air injection was added to the exhaust ports of the 3.5?

I'm also curious to find out if anyone knows why the raised sections on the head where the air injection tubes screw in exists on the original Rover head castings. Did Buick attach something at those points?

Would have been for ADR27A in 1976(?) California had emission rules years before Australia so the raised spots are for the US market.

No it's the fresh air pulses into the exhaust stream that I'm referring to. ADR27a was exhaust gas recirc, plus postive crankcase ventilation and fuel tank vapour capturing (charcoal canister).

I've checked the photos in David Hardcastle's books and there is no sign of the raised section on the Buick 215 heads, so they must have been added by Rover.
Also, the Pulsair injection was added in 1981. So that's about 15 years of production before it was used for anything. Very odd.

Originally Posted by wlb

No it's the fresh air pulses into the exhaust stream that I'm referring to. ADR27a was exhaust gas recirc, plus postive crankcase ventilation and fuel tank vapour capturing (charcoal canister).

I've checked the photos in David Hardcastle's books and there is no sign of the raised section on the Buick 215 heads, so there must have been added by Rover.
Also, the Pulsair injection was added in 1981. So that's about 15 years of production before it was used for anything. Very odd.

G`day ,

something i would have been interested in a couple of years ago , used to have a thing about rover heads .

My info is that pulsair came in with the last 3 figure engine prefix being 398 8.13:1 then went to the ( 81) 11D 9.35:1

The Hardcastle book i have has 300 buick head pics , they have something going on in that area , they don`t have the boss but appears like a thread hole , but not clear .

I have some early 80 3.5ltr 11D heads , actually ERC 0216 and some 90s 4.6ltr heads , HRC 2479 they all have the boss you ask about .

The 3.5 sd1 Rover car head actually have pipes inside the exhaust port that directs the air to near the back of the valve head .

The range Rover heads only have a hole that enters the exhaust port so it is not directed anywhere only enters .

The bosses may be from the early yank engine and maybe something to do with the factory Turbo charged motor , i think it was called " jetfire ' it was the 215 , don`t remember if it was buick or pontiac , both had alloy 215s similar but not the same engine even though both under the GM umbrella , seem to remember even the castings for the blocks were done differently .

All stuff i used to know once but no so interested now days .

Cheers

Thanks,

I'll check the books again tonight, but my recollection is that there is a photo of a Buick 300 head where there seems to be some sort of shadow or hollow in that location. I think there is a photo of the Buick Special (215) engine bay where you can see that they aren't present.

Not sure why I'm pursuing this. It just struck me as odd. I don't remember what the heads of my old '76 2-door looked like in detail but the boss is present on my early 1970 P5B and I believed them to be the original heads. That's what prompted my enquiry.

On a completely different topic - I don't suppose you know if there is anyway of identifying a 3.9 from a 3.5 block externally or by engine number?

Originally Posted by wlb

Thanks,

I'll check the books again tonight, but my recollection is that there is a photo of a Buick 300 head where there seems to be some sort of shadow or hollow in that location. I think there is a photo of the Buick Special (215) engine bay where you can see that they aren't present.

Not sure why I'm pursuing this. It just struck me as odd. I don't remember what the heads of my old '76 2-door looked like in detail but the boss is present on my early 1970 P5B and I believed them to be the original heads. That's what prompted my enquiry.

On a completely different topic - I don't suppose you know if there is anyway of identifying a 3.9 from a 3.5 block externally or by engine number?

Yep , the engine number prefix tells what it will be and with the 3.9 the suffix tells how many head bolts 14 or 10 per side , which relates to the combustion chamber sizes of the heads and if it wears tin or composite head gaskets.

3.5 didn`t have serpentine pulleys but either did early 3.9s unless it is a 93 KA RR they had 1 similar belt as well a Vs , depends how much of an engine is there but the prefix is best .