Junkyard Supercharger Project
Thread Starter
Senior Member
Joined: Feb 2014
Posts: 793
Likes: 5
From: Southgate, Michigan
Year: 1997
Model: Cherokee
Engine: 4.6 I6
If you are going to use 6 bigger injectors and add boost, you will need at least 30lb/hr. Anything 30, 32, 36 lb/hr can be made to work.
Stock 190HP uses 6 x 21lb/hr = 126 lb/hr for 190HP 126/190=.66lb/hr/HP
If you plan to add +100HP, you will need 66 more lb/hr of fuel. = 11lb/hr more from each injector. So you need 21+11=32lb/hr x 6 injectors.
This is as simple as I can make it. There is a lot more to it but this will get you close.
Stock 190HP uses 6 x 21lb/hr = 126 lb/hr for 190HP 126/190=.66lb/hr/HP
If you plan to add +100HP, you will need 66 more lb/hr of fuel. = 11lb/hr more from each injector. So you need 21+11=32lb/hr x 6 injectors.
This is as simple as I can make it. There is a lot more to it but this will get you close.
Thread Starter
Senior Member
Joined: Feb 2014
Posts: 793
Likes: 5
From: Southgate, Michigan
Year: 1997
Model: Cherokee
Engine: 4.6 I6
If you are going to use 6 bigger injectors and add boost, you will need at least 30lb/hr. Anything 30, 32, 36 lb/hr can be made to work.
Stock 190HP uses 6 x 21lb/hr = 126 lb/hr for 190HP 126/190=.66lb/hr/HP
If you plan to add +100HP, you will need 66 more lb/hr of fuel. = 11lb/hr more from each injector. So you need 21+11=32lb/hr x 6 injectors.
This is as simple as I can make it. There is a lot more to it but this will get you close.
Stock 190HP uses 6 x 21lb/hr = 126 lb/hr for 190HP 126/190=.66lb/hr/HP
If you plan to add +100HP, you will need 66 more lb/hr of fuel. = 11lb/hr more from each injector. So you need 21+11=32lb/hr x 6 injectors.
This is as simple as I can make it. There is a lot more to it but this will get you close.
Or you can keep your stock or 703s and only add 1 60lb/hr axillary injector and use the other SS box like I do in my kits and mount it before the SC so it will also act as a liquid/chemical intercooler (like meth) and lower your intake air temps by 50-60*F.
Only need to buy 1 injector instead of 6. Out of boost it will run just like stock and you don't have to 'tune down' the 6 bigger injectors to work at idle, cruise etc when out of boost.
Controllers cost the same, you save not having to buy 5 more injectors and get the benefit of liquid/chemical intercooling and out of boost it is effectively turned off and everything runs as stock. Passes emissions.
Only need to buy 1 injector instead of 6. Out of boost it will run just like stock and you don't have to 'tune down' the 6 bigger injectors to work at idle, cruise etc when out of boost.
Controllers cost the same, you save not having to buy 5 more injectors and get the benefit of liquid/chemical intercooling and out of boost it is effectively turned off and everything runs as stock. Passes emissions.
Thread Starter
Senior Member
Joined: Feb 2014
Posts: 793
Likes: 5
From: Southgate, Michigan
Year: 1997
Model: Cherokee
Engine: 4.6 I6
Or you can keep your stock or 703s and only add 1 60lb/hr axillary injector and use the other SS box like I do in my kits and mount it before the SC so it will also act as a liquid/chemical intercooler (like meth) and lower your intake air temps by 50-60*F.
Only need to buy 1 injector instead of 6. Out of boost it will run just like stock and you don't have to 'tune down' the 6 bigger injectors to work at idle, cruise etc when out of boost.
Controllers cost the same, you save not having to buy 5 more injectors and get the benefit of liquid/chemical intercooling and out of boost it is effectively turned off and everything runs as stock. Passes emissions.
Only need to buy 1 injector instead of 6. Out of boost it will run just like stock and you don't have to 'tune down' the 6 bigger injectors to work at idle, cruise etc when out of boost.
Controllers cost the same, you save not having to buy 5 more injectors and get the benefit of liquid/chemical intercooling and out of boost it is effectively turned off and everything runs as stock. Passes emissions.
Now does that 1 big injector just get mounted right before the intake manifold inside the pipe?
Right before the inlet of the supercharger. It sends the fuel thru the SC. The SC will then 'homogenize' it with the air coming in and mix it well. Here is where the fuel will cool the SC rotors, help 'seal' the rotors for better efficiency, and cool the heated air from the SC.
Or you can keep your stock or 703s and only add 1 60lb/hr axillary injector and use the other SS box like I do in my kits and mount it before the SC so it will also act as a liquid/chemical intercooler (like meth) and lower your intake air temps by 50-60*F.
Only need to buy 1 injector instead of 6. Out of boost it will run just like stock and you don't have to 'tune down' the 6 bigger injectors to work at idle, cruise etc when out of boost.
Controllers cost the same, you save not having to buy 5 more injectors and get the benefit of liquid/chemical intercooling and out of boost it is effectively turned off and everything runs as stock. Passes emissions.
Only need to buy 1 injector instead of 6. Out of boost it will run just like stock and you don't have to 'tune down' the 6 bigger injectors to work at idle, cruise etc when out of boost.
Controllers cost the same, you save not having to buy 5 more injectors and get the benefit of liquid/chemical intercooling and out of boost it is effectively turned off and everything runs as stock. Passes emissions.
BUT, you loose the air conditioning correct?
Is there any that are "better" than others? M-90's that is..
And what about pulley's and lining them up? Belt length etc..
Marty, You said above "In my kits" Do YOU make up kits for these?
And for the DIY peeps, What kinda price are we to assume to be "all in" for a DIY setup? 2000.00- 5000.00? OR under 1000.00?
Mine is a OBDII (1996 2.5/5spd, 2wd)
Thanks again and this is gonna be great! Can't wait to learn more.

Errol
HERE is most everything you want to know.
Don't have to lose the A/C. Yep lining up the pulleys and belt length is tricky.
2.5L an M90 is too big. Thought you had a 4.0L.
Don't have to lose the A/C. Yep lining up the pulleys and belt length is tricky.
2.5L an M90 is too big. Thought you had a 4.0L.
Thread Starter
Senior Member
Joined: Feb 2014
Posts: 793
Likes: 5
From: Southgate, Michigan
Year: 1997
Model: Cherokee
Engine: 4.6 I6
Right before the inlet of the supercharger. It sends the fuel thru the SC. The SC will then 'homogenize' it with the air coming in and mix it well. Here is where the fuel will cool the SC rotors, help 'seal' the rotors for better efficiency, and cool the heated air from the SC.
Thread Starter
Senior Member
Joined: Feb 2014
Posts: 793
Likes: 5
From: Southgate, Michigan
Year: 1997
Model: Cherokee
Engine: 4.6 I6
CF Veteran


Joined: Mar 2015
Posts: 1,203
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From: Northern CT
Year: 1995
Model: Cherokee
Engine: Turbo 4.0
QUOTE=shooptube;3258833]You can use the stock manifold and tensioner if you don't mount the supercharger directly on top of it.[/QUOTE]
I am aware.
So then, top mount kit minus the split second and supercharger how much?
I am aware.
So then, top mount kit minus the split second and supercharger how much?
Thread Starter
Senior Member
Joined: Feb 2014
Posts: 793
Likes: 5
From: Southgate, Michigan
Year: 1997
Model: Cherokee
Engine: 4.6 I6


