engine mods

waht engine mods

  • good head porting and cams

    Votes: 36 27.7%
  • good head porting and 1397 with stock crank

    Votes: 20 15.4%
  • good head porting and 1397 with 08 crank (1441)

    Votes: 57 43.8%
  • stock bore and stroke it

    Votes: 17 13.1%

  • Total voters
    130
guys, you are confusing me...
I am riding over 20K miles a year (street, highway) bike pushes 164HP on the rear wheel with +-115Nm. Engine (2005) is stock with TRE and 4-1 custom pipes (builded myself). I was thinking to get little more tourqe:) Some guys say to go with 1340/1390 mod, other say gas flow headers and cams (whatever that means) and finally just putting 43 tooth sprocket could do the job. I don't understand technical language that well, so please help to translate to idiot's language. I would like to have more tourqe for everyday use where realibility is main goal. I don't have much cash to play with. I don't wanna go over 300 km/h either, but just to accelarate like hell. Any ideas??? please help. At this stage I have 5 diff opinions with 8 diff quotes.
 
If you're just looking for more acceleration and dont really care about top speed then I would definately lean towards just regearing. You'll lose some topend speed but it'll make a huge difference in acceleration!
 
Well to start with the 4-1 exhaust you made gave you 0 horsepower. You need to get a full exhaust first. That is going to give you the most horsepower for your money . Power is always gained in the header. The exhaust companies spend alot of time and money to design the primaries as far as length and pipe size. Unless a muffler is super restrictive you are not going to gain anything but noise from a slip on. Next tune it then gear it to your riding style. Everyone has a preference as to what gearing they like because everyone rides differently. I am guessing it is a pre 08 so probably mod the air box as well before tuning. Your going to have to do all that anyway if you want a big bore kit. Then again you said you are short on cash so I think the bigger bore is out of the question. You can always find a used exhaust on e-bay for cheap. HEADER_TUNE_GEAR
 
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Well to start with the 4-1 exhaust you made gave you 0 horsepower. You need to get a full exhaust first. That is going to give you the most horsepower for your money . Power is always gained in the header. The exhaust companies spend alot of time and money to design the primaries as far as length and pipe size. Unless a muffler is super restrictive you are not going to gain anything but noise from a slip on. Next tune it then gear it to your riding style. Everyone has a preference as to what gearing they like because everyone rides differently. I am guessing it is a pre 08 so probably mod the air box as well before tuning. Your going to have to do all that anyway if you want a big bore kit. Then again you said you are short on cash so I think the bigger bore is out of the question. You can always find a used exhaust on e-bay for cheap. HEADER_TUNE_GEAR

As far as 4-1 is concern this is full replica of DBE. You right about all companies spending lots of money on the research, but bottom line everything comes to law of physics - get those gases out as soon as possible with minimal air disturbance during the process and keep weight of the exhaust as low as possible. Now, if I got this right - to have better acceleration but scarifying top speed I must do 43 tooth sprocket. If I want better acceleration all the way to top speed I must do some engine mods. If so, which mod (1340 kit mod or gas flow heads and cams) Is this the same or maybe those are 2 diff things? I want her to accelerate like a mad horse all the way from the bottom till top. Think about it like V8, it can go 250 km/h but get there in no time. As far as money goes - I can save some and do it in 3-4 months time. I don't wanna do something I won't be happy with. I am not turbo or NOS kind of guy so that is off the table. I can't make a decision if I don't know pros and cons of either of mod. Mechanics - they all say - don't worry you will be happy but they don't want to give me straight answer. That is why I come to you guys asking for help and maybe put some light on this.
 
or you can be like me and want about 200hp or as close to it as possible without taking the engine down or doing any gearing. i wanna know how much i can get out of doing only slight mods and bolt-ons. and i dont want to go 4-2-1 exhaust because i dont like the looks. and i dont want to lose the top end because of the whole, "its a busa and my top-end's higher than yours" thing. i want it to feel like a crazed beast on roll on but still say i can still beat anything out there on top end...or close to it...
 
or you can be like me and want about 200hp or as close to it as possible without taking the engine down or doing any gearing. i wanna know how much i can get out of doing only slight mods and bolt-ons. and i dont want to go 4-2-1 exhaust because i dont like the looks. and i dont want to lose the top end because of the whole, "its a busa and my top-end's higher than yours" thing. i want it to feel like a crazed beast on roll on but still say i can still beat anything out there on top end...or close to it...

WOW Yoda, You are asking for a lot. Im with you though on the exhaust. I want to stick with duals. So an after market pipe is pricey. I will stick with stock and my yosh slip ons that dont do any thing for power BUT gives it a nice little grunt sound. Hell if they were to loud I would of put the stock mufflers back on. I know loud pipes save lives BUT i would rather be stealthy. I'll sacrifice the extra 10hp for now.
OK, as far as more power and low money, you can go with the intake cam on the exhaust side and either get another intake or run stock. I would also add higher compression pistion and a mild port. From what I have been researching. If you just save some money and open the motor once. GO WITH A 1397, mild compression, ported head,cams. If you need a crank add a 08 crank to bump it up to a 1441. Most of the builders on here have built them and make good numbers. Very streetable and run for thousands of miles with no problems. No over heating and no need for 2 batts. Depending where you live ,i'm sure I have talked to the builder near you. I have talked to almost all of them from east coast to west coast. They can all build a good 1397 with good power for the street.
With what ever you pick you will need something for programing the fuel. Weather you choose a pc3 usb or just get yours reflashed. You will want to open the air box up too, with the small air box mod.
If you watch the busa forums you can get good used stuff for your project. Hell sometimes you can get new stuff for used prices.
As far as the regearing, YES you will accel fast and the wheel comes up alot easier BUT when you just want to cruise your rpms are higher than stock in sixth gear. I went with just a stock front 17 and 42 in the rear. I get the vibrations at cruising speed and it eats the fuel more. Not sure if I like it. I just deal with it. I was wondering if I should of tried a 43 in the rear.
OK so after all of this. If you want to accel quick experiment with the sprockets. You can find them used and cheap on the forums.Step it up to cams OR cams and higher comprission mild port. Realy step it up and go with 1397 ,cams , port.

Sorry for rambleing.
 
yeah, my biggest thing is, i've got 23k on my 05 right now. i ride my 45min hwy commute to work more than half the year on my busa. i dont want to have to crack'er open every year or 4 just because im pumpin more into the engine than she was intended to handle and to just replace valve springs or whatever. i want somethin thats gonna run on and on and on like she is now. movin cams over doesnt sound too bad like yall are sayin, but whats with all the 1397 stuff? are you referring to a big bore?
 
yeah, my biggest thing is, i've got 23k on my 05 right now. i ride my 45min hwy commute to work more than half the year on my busa. i dont want to have to crack'er open every year or 4 just because im pumpin more into the engine than she was intended to handle and to just replace valve springs or whatever. i want somethin thats gonna run on and on and on like she is now. movin cams over doesnt sound too bad like yall are sayin, but whats with all the 1397 stuff? are you referring to a big bore?

Yes, the 1397 is a big bore. From talking to the builders, they can be built to live on the street for a long time. The key to what I found is , to not get crazy on the compression and not to go with the really big cams that beat the hell out of the head. You can build a good, reliable 1397 for the street with good hp. As far as the valve springs they would need changed if you did the 1397. Ape 65lbs. Price isnt to bad. OR if you have time try and hunt them down used.
 
I am in the same boat, I have a 99 copper with a bearing that went bad. I am taking the Motor out tomorrow. The builder builds race bikes, he told be to go back stock with starter mods, high pressure oil pump and somethign with valves. maybe puuting exhaust valves on intake or vice versa. He told me the bike is fast enough. I was thinking about stoker kit and all that stuff, but I quess it depends on how deap are your pockets.
 
Well I couldnt do what I wanted to do with the money I had ,so I ended up finding a decent stock motor and just swapping it out. Now I have my motor sitting and ready for when I get the money together to do it right.
If your looking to rebuild yours, depending on how many miles you have on it. You might want to do the same thing. That is what I was told when I thought of just rebuilding mine back to stock. Just to get it on the road. I had 20k on mine. After you upgrade here and rebuild there you are right at the price of a decent used motor. I went from a 2000 with 20k to a 03 with 6900. Swapt it out this week and she is up and running for the weekend. Runs great. Im very happy =)

If you do want to hop yours up and save money, you can put the intake on the ex and get and another intake and some guys remove the base gasket to bump the compression up some. Get it remapped and you should be happy. I would bump the compression with different pistons. Its a little more money but I think more affective.
 
If you do want to hop yours up and save money, you can put the intake on the ex and get and another intake and some guys remove the base gasket to bump the compression up some. Get it remapped and you should be happy. I would bump the compression with different pistons. Its a little more money but I think more affective.

yea i was thinking of doing this ive herd good numbers come from just this set up im a mild street rider so it should be just enough plus theres always nos.. lol

:beerchug:
 
Very true, mine had 12:8 on box and were actually over 13:5

If someone told you a 1441 would not get 220 hp get another builder. And a stock bore with head/cam and 08 crank will get you in the 200 range too. But the 1397 pistons make a BIG difference. If you line-up next to one you will be sick if you sleep on that upgrade. I would stay way from the 5mm crank if you put alot of miles on it.
 
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air is power. so a small bump in displacement and some head work would probably realize more gains than any of the other combinations.
 
I can't afford a turbo so I'm going Brock's full exhaust, intake on the exhaust side w/adj. cam sprockets, PC V with datalogger, along with the basic stuff like PAIR blockoff, possible gearing change, throttle valves (butterflies), etc.. This will produce a nice reliable street motor. Then next Winter when my warranty runs out I'll be adding Harry's head work, fix my squish with a thinner base gasket (to be determined during build?), and if I can afford it maybe a BB kit?

Talk to the guys at Brock's and they'll hook you up with their excellant customer service. :bowdown:
 
im probably one of the ones you read up on. i have no headwork YET or crank. i opted for an oem crank for the same money reasons. im right at 200 on a concervative dyno. i dont think you need to cut your tranny though. i went with some hd clutch springs and valve springs. i paid 4800 for the kit, oem crank, carillo rods (800.00 of it) je pistons and misc. stuff.


I would get that tranny done,I made the mistake of getting work done to my motor and the builder told me, if you miss a few shifts with that HP that tranny will be gone,and sure as can be it was shot, Spend the extra Money and have it cut, I went thru Fast by gast,but there is alot of site sponsers that will take care of you also,I just want to make sure you do not get stuck yanking the motor and then spitting the cases then sending the trans out,hoping it is just 2nd gear and not tore up Shift forks,shift shafts,shift drum,Dogs gears on the trans so bad were you have to pay extra $$$ for.I am not trying to scare you,just save you time and money in the future.:beerchug:
 
I'm a daily rider and going to have Goldenchild do a 1397 kit with porting and a little bit of NOS for the track . I don't need a crank but if I did I would get a new 08 one .
 
I'm a daily rider and going to have Goldenchild do a 1397 kit with porting and a little bit of NOS for the track . I don't need a crank but if I did I would get a new 08 one .

That sounds good. Goldenchild is a good dude. That setup should make some good power.Keep us posted.
 
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