Hello guys
I own a brand new big tube replica and a friend of mine has a bisi replica and he wants to trade it for the big tube but i am not sure witch header will be more usefull for my motor i run a b20 v currently putting 180hp to the ground with shitty 4-1 header and 2,25 wanted to put big tube with 3" but now i dont know witch to choose
Thank you in advance

 

i hate replica's. People put so much time and money into the R & D and some chinese guy buys one and copies it. its retarded. buy the real deal or dont buy it at all please.

 

does not answer my question but thanks for sharing
if i could afford a real bisimoto header i would buy it but since i cant i am looking for the second best thing out there

 

Sell both. Don't run either one.

 

The "only" test done openly on a bisi replica header was mikey spec's test, which needless to say , it showed the header needs more work and tuning which mikey ran out of time to do.

If you have a to run a replica, the only replica i'd really look into running is the SMSP b19 plm copy.. other things haven't been copied very well, but that header is pretty straight forward.

 

i understand guys thank you for the advices but the sad thing is that i really need to choose from one of the 2 headers
I will probably keep my big tube because i have seen 1-2 many guys runing the big tube replicas and get desent gains and i have no feedback about the bisi

 

What mods do you have.. Stock b20.. b20 vtec..

More info. Also I am not sure that the headers aren't going to change your power very much. The big tube i believe is for free flowing HIGH rpm power.. For your setup id go for this BISY.. i mean its prolly your best bet. Dont think youre reving the b20 very high.

 

84mm
11:7:1 cr
stock rods

stock pr3 head with ITR cams, valve train and valves
Aebs intake and 64mm tb ,skunk2 cam gears
That is about it
the engine is tunned and the peek is at 7800 my rev limiter is @ 8500
Thank you in advance

 

That bisi rep is not good for a b20v its to small of a collector if a b18c1 its good which mikey will test sooner or later

 

it is not small the runners are as wide as the big tube's

 

the bisi replica is not good...my bisi v2 has a 3inch collector

 

My real bisi made for a 1.8 has a 2.75 inch collector and all the 2.0l ones all have a 3 inch so yeah its small

 

https://honda-tech.com/forums/performance-45/new-ultimate-b-series-v2-header-1-8l-2-0l-2916203/
this is the one i am talking about
so your advice is to stick with the big tube ?

 

Just stick with the big tube rep until you save up enough for a REAL header.

 

unfortunately this will be the header that i am going to use
i doubt i will be able to spend 1000+ on header but thank you guys you helped me choose between the 2 headers that i can use
i will stick with the big tube and will run 2,75 or 3"
Kind regards

 

dont go big tube...get the regular replica...the bigtube is made for 2l engines with big cams and compression..ur b20 is making less power than what the regular tube header is made for...bigger is not always better...

 

I just had my header made for my 86mm motor and it has a 2.75 collector

 

Lies, I doubt it a bisimoto header

 

my header is made for a 1.8l lsvtec and it has a 3 inch collector..but i am running a 3 inch exhaust...so maybe thats y..

 

all those replica headers crack...they use inferior materials to originals....look at the hyend header...it has good ground clerance and will make just as much power as the other replicas...if your going with hytech replica get the small tube...your not running enough motor to make power with the big tube and they all suck 80% of them bottom out cause clearance sucks..

 

well i am planing on further upgrading the motor s2s2 cams ,s2 valves ,p&p and few other minor things hoping to get around 205-210 whp with good tuning
Will the big tube be effective than ?

 

Check them outthey are on his facebook page its a red eg

 

Who's facebook? If its a knock off one yes its 2.75 but if its a real bisimoto header I'm sure it would be 3inch

 

a local guy is selling a real bisimoto that he had made for a b20vtec 11.1 compression with bisi cams and his is 2.75 collector..

 

Hmmm maybe I was wrong or they are getting away from using a 2.75inch collector since it sucks and you can't attach it to anything the 3inch is a lot better IMO