21 replies to this topic

[hanra]

It would be nice to use the correct inlet manifold for my my 75 SLR 5000. I think the quadrajet that I have is a late 74 SLR 5000 carb judging by the numbers.

Ive found an inlet manifold here which has this cast number: 2823087. Now its a different number to the LH parts book, but sometimes a P/N and a cast number can be different...?

Any ideas what this is from? What is the correct manifold to use? If this isnt right? Does anyone have the right one?







Whats this??????

[hanra]

Well my ADR tag is just 27. So that is pre pollution? That other bit is actually screwed into the manifold????

[hanra]

Some one with an original SLR 5000 able to please confirm the cast number on there manifold?

[76lxhatch]

That thing is the choke bi-metal spring housing, it screws into the manifold because it needs a small amount of vacuum to suck the hot air from around the exhaust via the tube which goes over the driver side rocker cover (this hot air causes the spring to relax and the choke to disengage). Pop the cover off by undoing the three adjusting screws completely and you'll see how it works and attaches to the linkage which connects to the choke lever on the other end.

[hanra]

So is that choke housing supposed to be there on 75 LH SL/R 5000? And what will do about an auto choke if Im running extractors..?

[fuzzypumper]

I would say so.
My pacemaker extractors have a tube welded around cyl 3 outlet to cater for auto choke heater tube.
The manifold I have has the same numbers as yours, but I got mine off ebay and wasnt on the car as original.
The number resembles a HQ type but wouldnt be surprised if they used those on the pre poll LH.

[fatslr]

I have just checked the number on a manifold I have hanging up in the shed which was on my LH SLR5000 it has the same code as yours 2823087 .
it was a matching number car so I would be fairly confident that this manifold was the original item.

Garth

[76lxhatch]

And what will do about an auto choke if Im running extractors..?

I've currently got a set of Pacemakers which have the tube fuzzypumper mentioned, this works well. Previously I had the end of the tube tucker down beside/beneath the middle primaries which didn't work quite as well but was still adequate - just make sure you adjust it so that the choke is completely off when warmed up.

[hanra]

HI Garth!

Thank you very much for your efforts. Sounds like Ive got the correct manifold then!

Cheers guys!

[hanra]

Hmmmmm..... I think Im going to have to start asking for pics of this fuzzy pumper setup??? Ive never seen the original set up so I dont have much of an idea of how any of this should look....

I often wonder if there is even a need for a choke up here in the north anyways....?

Edited by hanra, 21 December 2011 - 06:34 AM.

[fuzzypumper]

I "had" that setup, Sorry no pictures.
Back then I got sick of the constantly pulling apart the prepollution rochester I was running. it was very tired and never ran right.
So I switched it out for a holley with electric choke and pulled off old choke from manifold.

Maybe 76lxhatch has some pics for you.

[hanra]

76lxhatch..... pretty please may I get a picture!!!!

I noticed it looks like this setup is full manual???? Maybe thats easier?

[76lxhatch]

Yuck, that's a hack job. There's nothing wrong with the auto choke if properly set up, they work well.

What specifically do you want pics of? This is pretty close to a factory setup:


I have a later model carb with the choke housing hanging off it rather than the manifold (using a Performer now) but the concept is the same - can take a pic of the tube around the exhaust header if you like.

[hanra]

Yes please. I dont quite know how Im going to get the choke to work with the extractors... I dont know what sort of pipe to use? How to wrap it? Ive never used that choke on any of my old cars. We dont really have cold mornings up here. Is the tube hollow copper or something?

But yes any pics you have of this setup would be greatly appreciated so I can get a better idea of things!

[76lxhatch]

The tube around the extractor primary is just a steel U:


You can use pretty well anything for the heat pipe, normally a piece of bundy is the easiest with a single or double flare on the choke housing end and a suitable nut to screw it on. Copper would likely be fine too. I'm pretty sure the original was insulated to keep the heat in a bit, but it doesn't really seem to matter much (I guess it cools a little faster without it but you don't generally need to run a lot of choke) - as you can see the one I have at present isn't wrapped at all and it works fine, gives me plenty of choke while still turning it off completely. Cosmetically for originality's sake I seem to remember seeing an original one with a kind of string insulation wound neatly around it (e.g. like you'd see a rope around a winch).

[hanra]

Oh ok! WOW! Good one. Thanks for that pic mate!

Is the extractor end left open or crimped closed? The stock setup passes through the header yeah? For some reason I thought there was two pipes??

[V-SLR5000-P]

The part number indicated in the LH series catalogue is 9929854. My October 74 HT engine has a manifold with casting number 9929853, but it is common for the part number and casting number to vary by 1 in the last digit. I also have a spare manifold with casting number 2823087. The 2823087 manifold seems to be identical to the 9929853, maybe its a later version of the same part?

Edited by V-SLR5000-P, 22 December 2011 - 07:56 AM.

[hanra]

This is what I was thinking of. Where does the other end of the heat pipe plug into????

[76lxhatch]

The other end of the pipe is open, it has to suck air from somewhere - its just heated as it passes through.

The basic stock setup I've seen (probably applies more to full sized Holdens) just has a kind of extra little cover over the exhaust manifold which traps some heat. None of them have anything at the other end (they certainly don't go into the exhaust or anything), its only sucking fresh air which is heated along the way - its the heat transfer which is the important part.

edit: that one above actually appears to have the open end attached to the air cleaner, I guess that would avoid it getting blocked up, big ugly loop though

Edited by 76lxhatch, 22 December 2011 - 11:18 AM.

[hanra]

Awesome bit of help there mate!!!!! I once was blind but now I see. But Ill be blind again this weekend!!!!!

[yel327]

That manifold is a HQ-HJ and LH- mid 1976 LX 308. Almost the same as a HT-HG 308 except they are drilled and tapped for a heater hose connection on the front crossover on that round pad just to the passenger's side of the thermostat.

Good to hear the extractor wrapped choke pipe works. I was thinking about extractors on the HJ Premier as I snapped some of the exhaust manifold studs off, and I have some here ready to go with that pipe on them.