rover v8 supercharger
rover v8 supercharger
hello ive got a rover v8 and was thing putting a supercharger on it it has a 450 holley on it at the mo, do you have to change carb to a blow through system?? i new to supercharges so i might be way off track cheers
Depends what type of supercharger you put on it. There is the traditional Roots type superchargers mounted on the manifold with the carbs or injection on top and then there are the vane type superchargers hanging of the side of the engine like an alternator or aircon pump. These later types can be blow through or suck through.
With carburetors there is a limit very early on with the blow through systems as carburetors react to air flow (volume of air) and can't compensate for air density (when compressed). This can be overcome somewhat with slightly richer than usual jetting but it is a compromise at best. Fuel injection with a mass airflow sensor (hotwire) will measure the air density and are therefore much better suited to blow through systems.
Usually carbs on blow throughs are also mounted in a box so the whole carburetor is exposed to the higher air pressures so set up is much simpler as the fuel flows through the jets and emulsion tubes due to the lower pressure in the venturies. Without mounting the carburetor in a box you have to reference the air pressure in the fuel bowls to the boost pressure to ensure proper fuel flow.
There is tons of information on the internet about the benefits / pitfalls of either system and the pros / cons of supercharging versus turbocharging.
Personally I'd go for turbocharging if I was going to force feed my Rover V8.
With carburetors there is a limit very early on with the blow through systems as carburetors react to air flow (volume of air) and can't compensate for air density (when compressed). This can be overcome somewhat with slightly richer than usual jetting but it is a compromise at best. Fuel injection with a mass airflow sensor (hotwire) will measure the air density and are therefore much better suited to blow through systems.
Usually carbs on blow throughs are also mounted in a box so the whole carburetor is exposed to the higher air pressures so set up is much simpler as the fuel flows through the jets and emulsion tubes due to the lower pressure in the venturies. Without mounting the carburetor in a box you have to reference the air pressure in the fuel bowls to the boost pressure to ensure proper fuel flow.
There is tons of information on the internet about the benefits / pitfalls of either system and the pros / cons of supercharging versus turbocharging.
Personally I'd go for turbocharging if I was going to force feed my Rover V8.
1992 Land Rover Discovery V8i, 5 speed, 12000lbs winch, Salisbury rear, 110 front, 65mm spring lift, dents in every panel, Rallywoods pinstriping.
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Steve_t647
- Hard Yaka
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- Joined: Wed May 17, 2006 12:00 pm
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The carburettor can be mounted in two positions on a turbo-charged or supercharged engine, and a great deal of controversy exists as to which is better.
The carburettor can me mounted such that it feeds air into the turbo/supercharger then the turbo/supercharger feeds it to the engine.
This is known as a Draw-Through system.Under these conditions the carburettor operates more or less as it would on a naturally asperated engine all you have to do is move it and the cables throttle linkages etc.
Another school of thought says that the carburettor should be mounted between the charger and the intake manifold. This means that the charger draws fresh air and pumps it into the carburettor, which then feeds the fuel/air mixture to the engine. Only this setup allows the use of an intercooler. In fact there are several advantages to a blow through over a draw through because the fuel/air does not have to travel through the turbo.
With the draw through having a blow off valve style pressure release at 15 or 10 psi higher than the usual manifold pressure would be nice just in case you get a backfire into the compressed and fuel laden mix (think saftey valve).
The blow through system requires a boost sensitive rising rate fuel pressure regulator in order to increase fuel pressure with boost pressure as the rpms rise.
The differences are quite big so some reading may be in order. My own personal preference to date has been for the draw-through system, but this need's the saftey valve to be made, causes more wear on the supercharger, forces you to relocate the carb, fuel lines and throttle cable etc. The blow through system meen's modifying the carb and bolting everything up in a box. Oh and if you get a backfire you can blow the supercharger off the manafold and destroy the screws or impellers (stall the charger)
Here is an enclosure for a blow through setup
[url]
http://www.superchargersonline.com/prod ... V8M205-012
[/url]
Here are the modifications done to a carb to suit a blow through setup
[url]
http://www.vs57.com/carb.htm
[/url]
Here is a charade supercharged they ended up going to injection I think
[url]
http://www.cardomain.com/ride/2265802/1
[/url]
Hmm but all that said it is a good mod if you are looking for low end torque! if you are looking for high end RPM a supercharger is not the best option and a trubo would be more suitable. Also in a carbed enviroment running more than 5 PSI is risky supercharged or turbo without work on the carb.
maybe this should have been a book
I personally think in your situation with the V8 there is a lot of work that can be done to the 8 before charging, Higher compression (shave the head) cam's etc to get more power rather than a charger and a turbo would suit better.
just my .05c (swedish rounding)[/url]
The carburettor can me mounted such that it feeds air into the turbo/supercharger then the turbo/supercharger feeds it to the engine.
This is known as a Draw-Through system.Under these conditions the carburettor operates more or less as it would on a naturally asperated engine all you have to do is move it and the cables throttle linkages etc.
Another school of thought says that the carburettor should be mounted between the charger and the intake manifold. This means that the charger draws fresh air and pumps it into the carburettor, which then feeds the fuel/air mixture to the engine. Only this setup allows the use of an intercooler. In fact there are several advantages to a blow through over a draw through because the fuel/air does not have to travel through the turbo.
With the draw through having a blow off valve style pressure release at 15 or 10 psi higher than the usual manifold pressure would be nice just in case you get a backfire into the compressed and fuel laden mix (think saftey valve).
The blow through system requires a boost sensitive rising rate fuel pressure regulator in order to increase fuel pressure with boost pressure as the rpms rise.
The differences are quite big so some reading may be in order. My own personal preference to date has been for the draw-through system, but this need's the saftey valve to be made, causes more wear on the supercharger, forces you to relocate the carb, fuel lines and throttle cable etc. The blow through system meen's modifying the carb and bolting everything up in a box. Oh and if you get a backfire you can blow the supercharger off the manafold and destroy the screws or impellers (stall the charger)
Here is an enclosure for a blow through setup
[url]
http://www.superchargersonline.com/prod ... V8M205-012
[/url]
Here are the modifications done to a carb to suit a blow through setup
[url]
http://www.vs57.com/carb.htm
[/url]
Here is a charade supercharged they ended up going to injection I think
[url]
http://www.cardomain.com/ride/2265802/1
[/url]
Hmm but all that said it is a good mod if you are looking for low end torque! if you are looking for high end RPM a supercharger is not the best option and a trubo would be more suitable. Also in a carbed enviroment running more than 5 PSI is risky supercharged or turbo without work on the carb.
maybe this should have been a book
I personally think in your situation with the V8 there is a lot of work that can be done to the 8 before charging, Higher compression (shave the head) cam's etc to get more power rather than a charger and a turbo would suit better.
just my .05c (swedish rounding)[/url]
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Rotazuk
- Hard Yaka
- Posts: 937
- Joined: Mon Jun 16, 2003 12:00 pm
- Location: Auckland - New Zealand
- Contact:
I have 91 Rangie is reasonably good nick , sort of been waiting for the engine to give the slightest hint of trouble then it can come apart 
. I have a P76 crank , crack tested , Ford 255 pistons and the s/c to go on . This makes it a 4950cc v8 , hmmm . Its only done 105 thou miles so its does not look like giving trouble soon and I think I am going to sell it anyway .
The s/c cost me $1500 , so open to offers . It has the box to trick the factory ecu to run on boost , I have been told you just have to restrict the advance in the dissy a bit . Ment to be good for 245 hp on a 3.9 efi , factory 178 hp I think .
Cheers
Chris
. I have a P76 crank , crack tested , Ford 255 pistons and the s/c to go on . This makes it a 4950cc v8 , hmmm . Its only done 105 thou miles so its does not look like giving trouble soon and I think I am going to sell it anyway .
The s/c cost me $1500 , so open to offers . It has the box to trick the factory ecu to run on boost , I have been told you just have to restrict the advance in the dissy a bit . Ment to be good for 245 hp on a 3.9 efi , factory 178 hp I think .
Cheers
Chris
rover v8
well havent spent a lot on the old rover but its out of a sd1 and by what i know witch ant a lot its all ready a higher compression ratio and i have put new lifters cheacked heads and mild grind cam, new timing gear electronic dizzy and a four barrel holley 2 1/2 inch exhurst. supercharge down tourge sounds good keen as but its usualy the $ if ya know what i mean i.