I have a big bore throttle body custom made for my customer. I want to see what you guys think and if there is enough interest, I will start to retail it to general public.



http://www.rotaryextreme.com/tb-1.jpg



The top TB is the stock one. The bottom TB is the modified one.



The top 2 ports are ported by 4mm in diameter and also the center part is machined out. That will make the total flow area increase by about 20%. A custom merged one piece butterfly plate replaces the stock ones. I can have stock upper intake manifold machined to match with the top ports.



The target price for the throttle body modification is $400. The upper intake manifold modification is $175. All parts are CNC machined. The butterfly plate is made of 6061 T6 aluminum.



Chuck Huang

holy crap thats awsome

Quality part, nice work. Dyno run? May help to have some numbers to help equate performance gains vs. $

Think you can do that kind of work to my 20B Throttle body Chuck?

wow that is awesome! is the bottom hole enlarged any... what do you think performance gains would be?

The customer's car is at the bodyshop right now. After the car comes back in about 2 weeks, we will put it on the dyno to see what it does. Thanks.



Chuck

Yeah, I can have it done on your 20B throttle body. https://www.nopistons.com/forums/pub...IR#>/smile.png



Chuck

I didn't enlarge the bottom hole because the screws to hold the bottom plate are really hard to take out without stripping the head of the screws. I guess I will figure out a way to do it if people are interested in this mod. https://www.nopistons.com/forums/pub...IR#>/smile.png



Chuck

thats cool, i would definately buy one in the future...20% is a decent number..i'm sure many people would buy it

thats interesting

its better then feed 650 dollar bb throttle body

This is something anyone with a die grinder, a carbide burr, a steady hand and some patience could do in a couple of hours. Come to think of it I already did that to mine last winter. https://www.nopistons.com/forums/pub...DIR#>/wink.png I don't think it is a bad product but it is one that the average person could easily do themselves. Now making those beautiful bumpers of yours on the other hand is a talent that I can appreciate. https://www.nopistons.com/forums/pub...IR#>/blush.png

If you use a die grinder, it's not going to work because you can't grind that precisely. You also need to make larger throttle plates and the edges are not just flat, they have to be at an angle. If you take off your throttle body, the plates sit at an angle. If you make them flat, they will not seal properly and open at the proper angle.



If the throttle plates and the throttle body do not seal properly, you will have idle problem.



Chuck Huang

You might want to look at that picture real close again Dave, the entire butterfly has been swapped out, it is now a single instead of a dual. You can do the one at the top without much problem with a die grinder, but if you can make the bottom one with a die grinder I will buy your beers at rotorfest.

I didn't notice the butter fly. Yea I can see where that should be machined then. Of coarse technically some block sanding and a really steady hand with alot of skill and it could still be hand done. But If the price was good then it would make more sense to just buy your Chuck.

Will it be appx. the same price?

I guess everything is possible but I rather have it CNC machined then trusting my steady hand. I simply can't sell something that's grinded by hand when precision is a must. I don't have a CNC machine shop so I have to out-source on this mod. The CNC machine shop did a lot of work on this mod. They made the CAD program to machine the throttle body and also the throttle plate. They made a fixture so they can clamp down the throttle body onto the CNC machine. $400 is not cheap but there is a lot of work involved behind this.



If you can do it yourself, it's the best. Everyone likes to save money. Me too. https://www.nopistons.com/forums/pub...IR#>/smile.png



Chuck Huang

Yeah, it will be the same price but hopefully you can send me a few because the CNC machine shop does charge me for initial measuring and CAD programming. But your car is bad ass so I don't mind making no money off you. https://www.nopistons.com/forums/pub...IR#>/smile.png



Chuck Huang

Chuck your product is uber nice. I was just being a smartass.

https://www.nopistons.com/forums/pub...DIR#>/cool.png

There was nothing against you or any hard feeling at all. I am just trying to provide as much info as possible before someone starts to grind out their TB and then ended up needing a replacement. lol. https://www.nopistons.com/forums/pub...#>/biggrin.png



On the contrary, you can do the upper manifold mod yourself if you have proper tools. It does not have to be as precise as the TB mod.



Chuck

i want one

hottness, very claps

Definitely interested and could send you a TB right now! Nice to have an extra one lying around. :-)

I want to test it out on the dyno first before I offer it to general public. The customer who purchased the first one still has his car at the bodyshop. Hopefully it will be back next week so we can put it on the dyno.



Chuck Huang

wow looks sick man



such precise and well done pieace of aluminum

Any update on a dyno run.

eric

Dyno! Dyno! Dyno!

20% increase is that a guess or is there data?



what was the last dyno # on the customers car?

will there be back to back runs? <---that's what would sell it for me.



I assume there is a core exchange?!?!?!?!

I will find time to dyno it during the Xmas vacation. That's the only time I can leave the shop to take the car to another shop to dyno.



Chuck

20% increase in flow area, not 20% increase in HP.



The flow area increase can be calculated easily with simple math.



When it's dynoed, it's going to be back to back. The part will be swap on the dyno.



There is no core exchange because you will need to send yours in to be modified.



Chuck

Chuck,



Do you think there will actually be any difference in the dyno runs since the UIM and LIM runners are smaller than the stock TB plates already? I have big bore TB that i haven't had a chance to dyno yet..... but i don't know if i'll see any real difference. Even if the UIM/LIM are ported...... the stock TB plates are bigger than the surrounding metal on the runners would allow to be port matched.....

hmmmmmmmm. . . this is VERY interesting!!!



paul

I assume there is no gain in HP since the TB flows plenty for our engines. Don't forget the TB feeds both rotors and only one a time uses the charge. Our engines can consume 400cfm at 9000 rpms at best. A 40mm TB flows about 90 cfm. We have 3 of them which makes it 270. Times 2 will give you plenty. The real question is how much do we flow through the primary vs secondary? If someone puts a mega port on the primaries he might run out of air but that is still doubtful.



Chuck,

it would be nice to have some effidence proven the theory wrong.



CW

I don't see where you need a MASTERCAM program to machine the throttle body. Am i missing something here?

The edge of the throttle plate is not flat. It's at an angle. You also want to make sure the the plate will seal the throttle body completely when it's closed, or you will have super high idle if it's leaking. This is the reason you can't really use a grinder to do it unless you are as precise as a CNC machine.



Chuck

updates?

Any updates on the results of the Dyno?



Cheers...

Hmm, I think it'll have more effect on a 20B as you have 3 rotors, ander very big LIM and UIM and intake runners, if you port and, then the stock TB is really the bottleneck I think..

mehr luft im throttle body ist auch gut fur ein 13B Rub20b. Mehr ist immer besser !