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Discussion Starter · #1 ·
has anyone ever or know of anyone who has fitted one to a zs in place of the plastic manifold?
 

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the lower manifolds are different so you'll need those, they wont have the air injection that the zs manifolds have.
control of the vis is different so they wont work properly.

if your going to turbo it then might be worth a look. just to replace a rattly zs manifold, proobably not worth it.

Drew
 

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Discussion Starter · #5 ·
the lower manifolds are different so you'll need those,
noticed the lower manifolds were different and the old 800's don't have the vacuum? for the injectors, would need a bit of machining on the zs angled manifold, the straight one should be OK.

control of the vis is different so they wont work properly.
it would need a little circuit building to provide the correct signals to the ecu etc.

I noted the vis operate at different rpm ranges on each motor.

Can the mems3 be reprogrammed/remapped to bring the vis in and out at different rpm?

The r800 throttle body looks like it will flow 30% more than the single body on the zs. I know the ZS manifold is more advanced and it could be horses for courses...
 

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Discussion Starter · #7 ·
on and working, lacking midrange as I still need to rewire the r800 vis motors, but very good above 5/5500rpm.

As the manifold is much shallower than the plastic one and leaves a lot more room in the engine bay, I was wondering if its worth enlarging the plenums, a bit of fabrication and alloy welding could see them 250-300% larger than r800 stock setup. Would there be a performance benefit by doing so?
 

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lot of work for that, i think the plenums are seperate till you get to the vis motor(s).

start with the motors and see where you get.

the ecu can be re-mapped, its not a mems3.

Drew
 

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Discussion Starter · #9 ·
rover 800 manifold is on, and vis are wired up, working and sending the signals back to the ecu...now has the mid range torque back.

whilst it is a different setup to the platic zs version, the old 800 produced the same amount of torque at the same revs and same amount of power at the same revs, so I am hoping it will not be down on power too much.

Cost... 50 quid for the rover 800 parts and an unexpected 40quid for machining the zs lower inlet pipes to mate up to it. A few quid to build the circuits to convert 4 wire vis to 2 wire vis.

If nothing else, it won't rattle or get ingested by the engine.

When the time comes, I'll get it rolling road'ed, I don't have a 'before' to compare to, but at least it will give an indication of where it is now on power.
 

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nice for r800 inlet. Am working on a replacemnet plastic arm, first prototype finished and now testing.... hope it will go right and nothing will fail. Hope it will be installed in car till end of the march.
 

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rover 800 manifold is on, and vis are wired up, working and sending the signals back to the ecu...now has the mid range torque back.

whilst it is a different setup to the platic zs version, the old 800 produced the same amount of torque at the same revs and same amount of power at the same revs, so I am hoping it will not be down on power too much.

Cost... 50 quid for the rover 800 parts and an unexpected 40quid for machining the zs lower inlet pipes to mate up to it. A few quid to build the circuits to convert 4 wire vis to 2 wire vis.

If nothing else, it won't rattle or get ingested by the engine.

When the time comes, I'll get it rolling road'ed, I don't have a 'before' to compare to, but at least it will give an indication of where it is now on power.
Got any pics ? I thought about trying this ages ago but couldn't find the parts needed so it stayed just a thought :( good work for making it work ;)
 

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Discussion Starter · #16 ·
update,

could not successfully find the vis map in the ecu.

The car did 173bhp at the wheels (without remap) (whatever that equates to at fly?) and no amount of fuel or ignition could make any difference.

Does it work?
Yes it does.

Is it reliable?
Yes it is?

Is it any good for top end power?
Up to 6500 its great, but the car levelled off at 6500rpm, I assume (but not proven) that this may be all the manifold can do.


Is it worth fitting?
Yes, it is reliable, still has excellent torque through the rev band, cheap to do but if your after a screamer of an engine and pure bhp to 7k then think twice.
 

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The car did 173bhp at the wheels (without remap) (whatever that equates to at fly?)
About 208? (divided by 0.83). What other mods as that is impressive! ****** goes back ot start of the thread for a re-read*.

If i get a second manifold that I've been promised then I was htinking of gluing the valves shut for torque rather than gutting for top end.
 

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Discussion Starter · #19 ·
sounds good but what about the bottom end torque?

Drew
we ran with vis in all conditions

both closed
both open
balance open connect closed
balance closed connect open

then overlaid each dyno run.

Interesting thing was, there was 20lb ft difference between the best and worst configuration low/mid range.

power above 5k and below 2.7k was pretty much unaffected by vis position.

Anyway, with the vis configured right, mid range torque is very good, get the 3k and 4.3k surges as thats where the zs ecu operates, although could be bettered if the vis map could be found in the ecu as the r800 really need 2.7k and somewhere else (can't remember) then both closing at 5k - although above 5k is only worth 2bhp at best by closing them.

I think the limiting factor with the manifold for out and out power is its lack of plenum volume.
I may play about with a spare (if I can find one) and see if the volume can be increased, the great thing about an alloy manifold is the ability to chop and weld.
 

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we ran with vis in all conditions

both closed
both open
balance open connect closed
balance closed connect open

then overlaid each dyno run.

Interesting thing was, there was 20lb ft difference between the best and worst configuration low/mid range.

power above 5k and below 2.7k was pretty much unaffected by vis position.

Anyway, with the vis configured right, mid range torque is very good, get the 3k and 4.3k surges as thats where the zs ecu operates, although could be bettered if the vis map could be found in the ecu as the r800 really need 2.7k and somewhere else (can't remember) then both closing at 5k - although above 5k is only worth 2bhp at best by closing them.

I think the limiting factor with the manifold for out and out power is its lack of plenum volume.
I may play about with a spare (if I can find one) and see if the volume can be increased, the great thing about an alloy manifold is the ability to chop and weld.
If you are making over 200 bhp on an otherwise standard engine then the 800 plenum is'nt the limiting factor!! The cams are really soft in the 180. What els has been done? Eg manifolds, exhaust, de-cat etc?? Good work though!! Oh how did you wire the vis motors? Got any pics? Cheers.
 
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