Drag race only Horse Power?

respivey

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I have a mini pro funny car with a stock for now busa motor. I am useing a homemade air box and stock header only. How much H.P. can i get out of this motor running racing fuel with out hurting anything. I am takeing a guess of about 60.
 
If you pull the outboard coils you might only pull 60
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I think he is asking how much power can he add with Nitrous to the stock engine without hurting anything. Someone with more experience should chime in. If you are spraying with a wet system maybe 60. I don't think you will spray 60 with a dry system without maxing the injectors out. I think you had issues with that already. I think you will find that the rods will give up much faster in your application because of the weight.

Actually the transmission output shaft might be the weak link way before that.
 
I have a mini pro funny car with a stock for now busa motor. I am useing a homemade air box and stock header only. How much H.P. can i get out of this motor running racing fuel with out hurting anything. I am takeing a guess of about 60.
Since a stock busa makes about 155 and the stock fuel system can safely support about 225, a 60 shot should be fine. Even with that shot you are going to need to add fuel with either a PCIII or an instant rich box.

My last motor setup made 225 on spray with no probs using a PCIII with the hub for two maps.
 
Professer never used a dry system. Other than ease of installation not sure they are the way to go. If the motor goes lean you may need a dust pan to pick it up.My injectors (stock) are maxed out with my setup. If i go nitrous i will probably go to larger injectors or as i indicated a wet setup. Keep in mind this is a drag only car, no street.
 
Professor do you suggest a fix for the input shaft. Some ( Most) of the folks on this site cant even plug in a power commander.
 
Professor do you suggest a fix for the input shaft.
They make a heavy duty output shaft. It will require splitting the case to swap it out. It is 30mm instead of the 25mm the stock one is. Sprockets are readily available, but the shaft it is not cheap. Breaking a shaft and destroying a good set of cases is not cheap either.

I've read it is a know problem with some of the car conversion guys. It is also pretty much mandatory when going a turbo and drag racing them. I've heard of guys with pretty much stock bikes breaking them with wheelie bars and slicks but I have only seen one break at the track.

I almost swapped mine when I had my transmission built and decided not to. About $350-375

If you decide to go that route, might as well have the transmission inspected and cut. Add billet shift shafts. There are a few other mods to make them shift better and last longer with air shifters and Nitrous.

Expect to spend about $1000 for all the above with a new output shaft. I finally had to stop just before the shaft.

How hard you are hooking it up may be a factor in how long it will last in your application.
 
You have more options running a wet setup and you have the room in a car for the extra hardware.
 
Professor that is the info i have been looking for. Thanks a million. What about a slider clutch any ideas?
 
Professer never used a dry system. Other than ease of installation not sure they are the way to go. If the motor goes lean you may need a dust pan to pick it up.My injectors (stock) are maxed out with my setup. If i go nitrous i will probably go to larger injectors or as i indicated a wet setup. Keep in mind this is a drag only car, no street.
Above you say you have a stock busa motor, and then here you say your injectors are maxxed? Huh?

As far as the cure to the OUTPUT shaft problem, get a billet one. Fast by Gast did mine when they undercut it.

Wet vs dry: several guys here are spraying over 100 shots dry with no problems. Gixx1300R sprays up to a 200 shot dry.

My new setup uses stock injectors with a modified fuel rail and an aftermarket fuel pump and regulator.

But what do I or (most) people on this site know? - heck, I don't even know how to plug in a power commander.
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OK I was mostly refering to me as not knowing how to plug in a power commander this Busa thing is new to me, it looks nothing like a big block chevy and glide. i am running a homemade air box stock one wont fit also i am running a header with no mufflers.Installed a power commander and a air fuel ratio meter.This setup went way lean as expected.I am useing the stock fuel pump .I have installed a automotive efi pump with regulator not hooked up yet. This way i can up the fuel pressure if needed. Just installed a Innovate LM-1.Have only made a few burnouts and 100 footers.As soon as i am able to make a few full passes i will probably be able to back down on the injecters. Hope that makes more since.
 
Johnnycrash if this was your project what would you suggest. I am leaning toward the billet output shaft and undercut gears.Should i go with the slidder or keep my clutch setup?This will probably pretty well eat up my budget for the year.
 
When I read your first post I thought you were new to this.  Now that I've read a few of your posts I can see that is definitely not the case.  Sorry if I came off as a pr1ck at your "not being able to plug in a PC" comment.
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Most of us only upgrade the tranny after we screw up the stock one (like me), but with the added weight you're pushing I think a billet OP shaft and undercut gears would be a good idea (ESPECIALLY if you start throwing a lot of spray at it).  Again, I've had good luck so far with my FBG tranny with the above mods.  

With your Innovate I guess you can see where/when you are lean, so this should be a little easier for you even though you can't get it on the dyno.  I am confused as to why it would be running lean as-is though.

Now a dumb question:  are you sure it runs better with no can and stock header than it would through a 4 into 1 with a can?  Is lack of space the reason to not run a can?

I also checked out your pics of your car.  That thing is knutz!
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