Try RPI's RP4 cam, new timing chain/gears and new followers if your running a manual. Also, if you have old heads on try get hold of some decent big valve heads. What carbs are you running?
regards, stephen
regards, stephen
Take5
New Member
Or check the ultimate reference and tuning place "RPi Engineering - Specialised Rover Engines"
id stick with a couple of well balanced SU's. Either that or convert to efi.
webbers and the like are hard work, they fall out of tune quickly and are quite expensive.
webbers and the like are hard work, they fall out of tune quickly and are quite expensive.
DubaiLandy
Member
I'm running a 4.6 block and heads with RPI RP4 cam, all timming gear from my old 3.5 and a weber 500 (edelbrook) with offenhauser intake.
Loads and loads of power but the carb does seem to go out of tune quickly and the next mod will be a hotwire injection system ot of a 3.9 and a chip from RPI to fuel the 4.6 correctly.
If I had a sound 3.5 I would probably change the cam and fit fuel injection to get more power - the 4.6 is ace though!
Loads and loads of power but the carb does seem to go out of tune quickly and the next mod will be a hotwire injection system ot of a 3.9 and a chip from RPI to fuel the 4.6 correctly.
If I had a sound 3.5 I would probably change the cam and fit fuel injection to get more power - the 4.6 is ace though!
tacr2man
Well-Known Member
If you are using weber( or other american style carb) you probably find fueling irregularity at high incline angles. as they tend to flood or go weak when tilted causing power loss just when you dont need it.
With a 4.6 you will need to go quad SU on boxer type manifold, for best results , next best thing to fuel injection. Twin SU HIF44 is quite adequate for 3.5 or 3,9 or thougfh you need to find someone who has a range of needles and springs to set them up ideally. Fuel injection will probably work out easiest route. JMHO
With a 4.6 you will need to go quad SU on boxer type manifold, for best results , next best thing to fuel injection. Twin SU HIF44 is quite adequate for 3.5 or 3,9 or thougfh you need to find someone who has a range of needles and springs to set them up ideally. Fuel injection will probably work out easiest route. JMHO
since when have Weber been merkin?
I is at a loss as to how a fixed jet carb can go out of tune quicker than a variable jet carb like the SU?
tacr2man
Well-Known Member
Didnt say weber was american, Brackets said other american carby, eg carter, edelbrock, rochester etc.
Where are thefloat chambers on the 4 barrell carbys mostly froint and rear of the throttle body, therfore when on steep inline float level on front chamber becomes high that on rear effectively become lower in relation to level mark at jet pickup point. SUHIF on iclines not affected due to integral reservoir being below jet pick up in centre of carby so effective level stays the same .
Didnt mention staying in tune , however the SU is more efficient due to being variable jet, the needle meters the fuel and is machined to give correct mixture at relevant throttle depression. the fixed jet carby has a big step between primary and secondary jets mixture efficiency relatively speaking. case in point ford were always higher fuel consumption per engibe size than BL vehicles. Same reason that fitting SU to series vehicles was popular due to better fuel consumption than on origibal solex/weber
IMHO your personal belief in my opinions is not compulsory
Where are thefloat chambers on the 4 barrell carbys mostly froint and rear of the throttle body, therfore when on steep inline float level on front chamber becomes high that on rear effectively become lower in relation to level mark at jet pickup point. SUHIF on iclines not affected due to integral reservoir being below jet pick up in centre of carby so effective level stays the same .
Didnt mention staying in tune , however the SU is more efficient due to being variable jet, the needle meters the fuel and is machined to give correct mixture at relevant throttle depression. the fixed jet carby has a big step between primary and secondary jets mixture efficiency relatively speaking. case in point ford were always higher fuel consumption per engibe size than BL vehicles. Same reason that fitting SU to series vehicles was popular due to better fuel consumption than on origibal solex/weber
IMHO your personal belief in my opinions is not compulsory
Take5
New Member
Just to quote from RPi Engineering website on Weber 4 barrels, the float chambers are fore and aft, so on side slopes flooding of one bank of cylinders doesn't occur. They also mention some guff about excessive changes in pitch/attitude and how more resistant to flooding.
SU's are better, but the HIF44 (as fitted to Menstrual/Montego 1.6 and 2.0's) are only 1 3/4" max bore, so even a pair of these is choking your engine. Jaguar 2" SU's are as rare as rocking horse ****, and I woudn't want to try and balance 4 HIF 38's acquired from several scrapped Metro's...
SU's are better, but the HIF44 (as fitted to Menstrual/Montego 1.6 and 2.0's) are only 1 3/4" max bore, so even a pair of these is choking your engine. Jaguar 2" SU's are as rare as rocking horse ****, and I woudn't want to try and balance 4 HIF 38's acquired from several scrapped Metro's...
ya daft pillock - yu said other american - the implication being that the former (ie Weber) is also american - maybe yu shud have said "If you are using weber( or an american style carb)" but then I dont suppose a numpty like you would understand English!
if your fitting gas you may benefit from rpi's ignition advance amplifier if your running an electronic dizzy (no points), well worth the money. also, some of the plug leads they sell then open your spark plug gap a little.
tacr2man
Well-Known Member
TMHM please do not try and lecture to me on the use of english, due to your interpretation. Verbal abuse does not achieve much, other than perhaps to make you feel good , and help you to deal with some personal problem, that you obviously have, illustrated by your uncalled for aggression. You will not provoke me to a similar reaction. I finish by wishing you well.
with respect, i think you are confusing aggression with banter
