Four barrel conversion

cobraboy

Well-Known Member
#21
I've fooled around with a TIG welder in the past, but unless you are constantly at it the skill soon evaporates, it would take me eons to stick a set of headers together now, and they would not be pretty.
Dan at Demand Engineering threw a figure of 1700 quid at me to knock up a set of long tube 4-1 headers, TBH if I had a result on selling some of my surplus gear I think I would go for that.
 
#22
if you had a more hairy cam then std manifolds would really really hurt it,

ive looked into trying a halfway house between standard and full blown tubular. i got hold of a pair of discovery manifolds which are twin downpipe, the n/s which is more compact would actually clear everything, o/s needs a notch in the chassis rail, so i probably wont do that, im temped to use a pair on mbg v8 block hugger headers, yeah every one says they are restrictive but they cant be any more than the standard cast ones
 

cobraboy

Well-Known Member
#23
Yup I have reasoned those Disco manifolds wont fit. I really don't like the collectors on those MG headers, I would keep what I have over those.
JP exhausts make the headers for RPI's P6 fitment, which is what Richard has. I asked JP if they would do me a set without a collector so I could extend them into long tube and put the collector under the car, alas they cant as RPI own the jigs.

If it was easy they'd all be doing it :rolleyes:
 

oldbloke

Active Member
#24
This has been on the cards for a long while, I finally got around to having a crack at it.
Until recently I owned a Ford High Performance Mustang 289 K code, the K code had a unique 4 barrel Autolite 4100 carb, this thing was the mutts nuts, so much nicer than a Holley.
When a friend had one for sale I grabbed it and built it up to be the same as the one fitted to the Mustang, my logic - if it made the Mustang's 4.7 litre go like the wind it would be OK for the 4.6 Rover.
It is not proven yet, but it is fitted and the car seems to like it, finessing the jetting is yet to come, but the hard work of getting the thing sitting on the Rover is done.
Nice and clean inside, valley gasket removed to allow trial fitting of Offy intake and port fettling
View attachment 14149
I went for a 1" phenolic spacer to improve torque and reduce heat transfer. The spacer is ducted underneath to the brass stub I tapped into the rear for a PCV system.
View attachment 14150
Manual choke Autolite 4100 on Offy 360.
View attachment 14151
I made a cable throttle linkage operating off the old auto kick down cable bracketry at the rear of the left cyl head.
View attachment 14152
K&N Filter and bling to finish off :)
View attachment 14153

Who knows, a set of downdraught's may be the next step ?
Well if you’re going with the downdraughts... this is currently setting in pals shop with owner bemoaning the fact it will never be smog legal to drive in California
! A666A0BD-13B5-4DD1-8007-8F72C44C82C0.jpeg
 

Ban306

Active Member
#25
Hi Cobra,
Thanks for the info on the bonnet scoop in the other post.
I am also very impressed with the figures you got Well Done
See you at the lights for a burn up lol :p
in my 2000 :oops:

Cobra is that also a custom built front valance ?
 
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cobraboy

Well-Known Member
#27
Hi Cobra,
Thanks for the info on the bonnet scoop in the other post.
I am also very impressed with the figures you got Well Done
See you at the lights for a burn up lol :p
in my 2000 :oops:

Cobra is that also a custom built front valance ?
Its a stock valance with some holes filled in and some other holes utilised for cooling.
 
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