The Long Awaited Bisimoto Dyno!

[d112crzy]

I have a hunch for why chose the design, and I'm sure it has to do with primary length vs primary pipe diameter(s) and keeping it all in a tight space.

How's the ground clearance on these?

[mndude07]

I have a hunch for why chose the design, and I'm sure it has to do with primary length vs primary pipe diameter(s).

How's the ground clearance on these?

Yeah, I was thinking the same thing basically. The header had to satisfy several constraints:

>the primaries length should be maximized
>larger diameter piping should be used in the bends to make up for the flow restriction of the curve
>a/c and p/s must be cleared


this design just happened to meet those requirements.

That's just my speculation though.

On the F/H/D/B series, all the accessories are in the same place though in relation to the header, so I still wonder why the design for the F and D series look so different?


Also, Cisco told me the clearance. Here was our conversation:

How's the ground clearance on the downpipe compared to say, a stock header or a typical ebay header?

Has a large and thick header outlet flange. My car is lowered in Neuspeed Race Springs on Koni/Neuspeed edition shocks set to middle perch. I have about 3-4 inches of ground clearance at this flange, which is the lowest point of the header.

Also, the oil pan clearance is adequate. I'd say atleast 1 inch.

I did have to notch out the front cross member for the piping after the collector to have sufficient clearance with any potential engine movement. I've heard of one other member having to do this as well.

Ok, my suspension is identical to yours, except I'm on the lowest perch. Sounds like good enough ground clearance to me. Notching the crossmember though...I have ESP mounts, do you think I would still need to do that? They are much stiffer than stock and don't let the motor move as much.

Correction, it technically is a 2pc header, but once you put it together with the 4 expansion springs, with the notch you can remove/install as 1 pc.

[dooey52_91CB9]

I cant wait to get my hands on this header so I can put all the other shit on at the same time. From the dyno sheet its worth the $629.

[turbo90accord]

dollar for dollar when it comes to the F22x engine its VERY hard to compare any parts performance to the parts that bisimoto produces. This is the only reason why i have bought nearly all of my internal parts from them.
I currently am getting a head ported through bisimoto and cant wait to recieve it.

IMO why would you waist money buying an inferior part and continue to give money to companies that dont care about their customer knowledge let alone have half the knowledge that the engineers at bisimoto have.

anyone can make car parts it takes an engineer with an education to make it actually work as intended.

[KeeleDesign]

great job.
I'd be more inclined to recomend your product now that you have given documented proof of it's potential.

I don't think anyone on here truely doubted you and your facilities. We are Just poor people who need inspiration for our dreams sometimes.

[bcjammerx]

I don't think people doubted you bisi...we wanted to know HOW much this header would benefit.

But what you've done here is given documented proof that not only does it have gains...

IT BLOWS THE COMPETITION INTO A DIFFERENT CLASS! This header is in a class of it's own awesome..exceeded expectations.

[deevergote]

26hp on a bone stock engine is DEFINITELY worth $630! It's easily worth $1300!

The engine, essentially, is an air pump. It only performs as well as the worst bottleneck will allow. On a bone stock engine, there are MANY bottlenecks that will choke performance. The stock intake setup, the exhaust ports, the catalytic converter... If a 26hp gain can be seen with all those things still in place and in stock form, then the gains seen from modifying those parts should be significant as well!


I was discussing things with d112crzy yesterday, and he said to me "I'll be impressed if there's a 10hp gain". I said I expected more, as I hold this header at least on par with (above, actually) the SMSP header for the H22. I was hoping for 15, maybe 18... but 26 even blew MY optimistic expectations out of the water!
Yes, that full gain is up top... but the gains throughout the powerband are noticeable as well.


Bisi, thank you for this header. And thank you for the dyno results! It is difficult to recommend a part that costs nearly as much as the car it's going on without being able to tell someone roughly what sort of gain they're going to see from it! Now I can feel 100% confident in telling someone that your header is completely worth the cost (even at the original price... at the discounted price, it's a freakin steal! the F22A guys just aren't aware of what a REAL header costs, as they have never had such an option.)

[alb_accord]

considering the dc header is $350 new, i think bisi header with this much gains its a steal for $630.

i would definitely buy one but i know down the road i will go turbo....

[Shadow1]

seeing a 26whp gain is making me want to screw the Func./Forms and get this. lmao.

[JoshM]

i would definitely buy one but i know down the road i will go turbo....

With the price at $630, you would definitely be able to make most of your money back down the road when you start your turbo build.

[sulimed]

hopefully this will get more ppl to sign on for the group buy

[gloryaccordy]

While this is exciting,

It was on an F22A1 with that awful 4-1 cast iron header. Plus it was 26WHP (which is still definitely a LOT) at the tippity top of the rev range... it was really only like 10WHP over peak (which is still a lot with the stock exhaust + cat, but not beyond the realm of a 4-2-1 header).

I know it's impossible to satisfy everyone, but I think a more meaningful comparo would be with this header on an F22A6 w/a 2.5" exhaust, and maybe the H-series upper IM vs that setup on a stock and Megan Racing type 4-2-1 header. That's more representative of the kind of setup this would be run on, and would provide better insight into the actual gains this would provide.

It's a beautiful piece of work & I'm sure it will make awesome gains with a tune... but for 4x the price of an OBX or MR header (which have been documented to make similar peak gains over the more superior A6/H23 4-2-1 headers) I need more...

[Macaqueistrong]

Jesus drove a F22 CB with a Bisi header, even the miracle worker knew how great this product is!

[kmart64]

While this is exciting,

It was on an F22A1 with that awful 4-1 cast iron header. Plus it was 26WHP (which is still definitely a LOT) at the tippity top of the rev range... it was really only like 10WHP over peak (which is still a lot with the stock exhaust + cat, but not beyond the realm of a 4-2-1 header).

I know it's impossible to satisfy everyone, but I think a more meaningful comparo would be with this header on an F22A6 w/a 2.5" exhaust, and maybe the H-series upper IM vs that setup on a stock and Megan Racing type 4-2-1 header. That's more representative of the kind of setup this would be run on, and would provide better insight into the actual gains this would provide.

It's a beautiful piece of work & I'm sure it will make awesome gains with a tune... but for 4x the price of an OBX or MR header (which have been documented to make similar peak gains over the more superior A6/H23 4-2-1 headers) I need more...

lol, what more do you want. If this was actually tuned, there would be gains every place on the powerband. If anything, on an a6 with those mods, there would be even more power. This is just to show you what can be gained on a completely stock motor. Also, if you really want to see a comparo, all you would need to do is dyno a megan racing type header, and then dyno bisi's header. No need to do all those other mods. This can't be beat for the price

[d112crzy]

If I were to provide a DC header, and ship it to you guys(Bisi), would you dyno it against yours? And then send it back of course.

I agree with what Yaw said, to a point. The header has big primaries after the steps, which led me to believe that the header was going to be too big for a stock f22. Turns out it's not TOO big, but it is big, that's why the biggest gains are seen after 6k. This leaves a lot of room for even more gains with the appropriate mods.

But I would definitely like to see this header go up against a DC header on the same motor.