FREQUENTLY ASKED QUESTIONS
How many more Horse Power will I get from the bored TB?
Unfortunately neither I nor anybody else can tell you exactly how much more
HP you can expect. It would be easy to say you'll get "X" number of HP but the fact
is that it depends on the size of your engine,
any other modifications you have made, how well the engine is tuned, and how much of a
restriction the stock TB was among others. On N/A Hondas, I have personally seen at the dyno
anywhere from 3 to 6 HP. On other engines, I have seen dyno tuning that made anywhere from 3 to 5 % gains. Proper tuning with a wide band O2 is the way to get the most out
of any modification. A larger TB works in conjunction with a good set of
header(s), intake and exhaust.
What gasket should I use?
I offer custom sized gaskets made to fit the larger bore of the TB. Please do not reuse gaskets as those can cause vacuum leaks wich will affect idle.
If you do not opt to buy a gasket from me, you need to use a NEW OEM gasket of the same type your TB originally had. TB gaskets
come oversized from the factory, you may need to enlarge the gasket.
Will my current intake fit the bored TB?
Yes, your intake will fit on the bored TB. I only machine the inside of the TB, the
outside dimensions remain the same.
Do you replace seals and internal gaskets on my TB?
No, rubber seals and gaskets are not replaced. It is recomended that you replace rubber seals and gaskets if your TB is over 10 years old.
Maxbore will install at no extra charge any seals or seal kits YOU supply at the time you send the TB in for boring.
Do I need to make any modifications to make the bored TB fit my manifold?
No modifications needed. If you are reinstalling the original TB you had, it is simply a
matter of installing the TB with a new gasket, and reconnecting the vacuum hoses, throttle cable
and sensors. If you are swapping TBs you need to keep in mind that some have extra parts like
FITV that may not work with your manifold. You need to make sure your TB works with your
manifold before sending it to get bored.
Do I need to send all the sensors that are on the TB?
No, you do not need to send all the sensors. For convenience, I recommend that you leave the TPS
on the TB. It can be difficult to remove and it requires to be reset to OEM specs once installed.
I do that as part of the job, but if you need the TPS you can keep it. All other sensors like the
MAP, or any other sensors or valves can be removed by you.
Do you enlarge manifold runners as well?
No. I only work on the manifold opening where the TB bolts up. Manifold port matching means that
I enlarge the opening on the manifold to the same size as the bored TB to make a smooth transition between the two.
Do you accept Group Buys?
I used to accept group buys, but I am no longer accepting them.
I think my prices are very reasonable and in most cases considerable less than other places.
What determines how big my TB can be bored?
The casting itself is the limit. Part of boring TBs is learning to identify possible problems like cutting holes
in the bore or making parts so thin that could actually collapse. In most cases, the walls around the shaft
are the limiting factor. As in the case of Honda TBs, the TPS well is the limit.
As you can see, I have left a thin but strong enough wall there. Any further boring could cause that wall to collapse or
Please email me if you have questions not answered here.