View Full Version : my custom 58mm Throttle Body

06-11-2009, 07:35 PM
Here it is my ported 58mm throttle body.

first i used a 2" wire brush($2.00) on a power drill to get the TB to the right size then i used a small engine cylinder hone($17.00) to make it smooth. I bought a 64mm bi-metal hole saw($17.00) and cut the throttle plate from a galv steel electrical outlet cover( wal-mare or home depot .50c to a $1.00) then i used a file to get it to the right size.


I will let you all know how well it works when i get it up and running.

Sorry about the large pics

06-11-2009, 07:36 PM
i also ported the TB mount on the intake manifold to match the TB

06-11-2009, 07:50 PM

06-11-2009, 08:20 PM
all that work i'm doing on the mustang TB is only going to net me 2mm more then you...

06-14-2009, 08:19 AM
experimenting with a spare tb next time i go to the yards or marks indoor junkyard

this would also work on a carb, which i have an extra laying around

joe's gt
06-14-2009, 09:51 PM
nice ingenuity!!! Good idea with using the cylinder hone to get it smooth. nice work.

06-15-2009, 03:09 AM
waste of time gl getting the idle to stabilize.
if you notice the butterfly is machined.

06-15-2009, 03:27 AM
Cool idea, but I don't think that butterfly is going to seal against the throttle body properly.

06-15-2009, 06:36 AM
we will see, if it doesnt i will just get a butterfly plate from a different car and make my throttle body bigger if i need to.

joe's gt
06-15-2009, 07:17 AM
waste of time gl getting the idle to stabilize.
if you notice the butterfly is machined.
not like your redneck racing invention.


06-15-2009, 04:40 PM
we will see, if it doesnt i will just get a butterfly plate from a different car and make my throttle body bigger if i need to.

good idea, you can use the supra plate.

06-15-2009, 06:08 PM
acatully if tou think about it all you gotta do is take a tb to a goo machine shop and ask them to bore the tb to whatever, then ask to make a matching butterfly plate

in his case if his plate dont work then he can go to a machine shop and get them to make a butterly plate.

06-16-2009, 07:32 AM
fyi i'm not a noob, and this should work. it is not that hard to adjust the idle, i'v done it before. i did all the work myself, not payed someone to do it and if it noes not work then i will just get a throttle plate or have one made.

06-16-2009, 07:33 AM
also piston is under constant pressure and heat, the throttle plate is not and the galv steal i used is a lot stronger then the stock metal used for throttle plates

06-17-2009, 03:00 AM
that super hard galvanize your refering to is going to cut through the soft
aluminium throttlebody bore, thats why smart people like me keep the SOFT bronze so neither wears and keeps the PERFECT seal it was intended for.

06-17-2009, 03:21 AM

06-17-2009, 05:08 AM
insulting other members or their projects will not be tolerated, consider this a warning

as for the throttle plate i know the 7mge and 7mgte both have a 60mm tb and some camry/lexus model v6's do as well. so if you wanted to be safe if you could bore another 2m those would work, or trim down the butterfly plate 2mm.

06-22-2009, 10:44 AM
im excited for the outcome.
Lets not bash guys, this can lead to ideas or be a warning to others if it goes bad.
Either way, its good information for everyone

06-22-2009, 08:32 PM
Nice... hope it works, if not you can always get a matching 58mm butterfly.

06-27-2009, 03:07 AM
thats the plan

07-25-2009, 08:21 PM
you know a loose butterfly blade in the throttle body might be a good idea if you wanted to delt. the idle air control system.

(some chevy and fords have holes drilled in the butterfly valve for idle)
(i also tried this on a 3sfe motor and it worked well, no idle bounce 1200rpm idle when cold 1000rpm idle warm. but i will give a warning if you live in a state were its cold (below 40f in winter) not the best idea because the car will not idle well (or by its self when cold) in the winter time)

all in all its a great idea and i think you enjoy the benefits of a bigger tb


08-02-2009, 05:15 AM
i am going to plug my idle air control valve and see how it goes, i also got a butterfly plate from a 89 camery v6.

08-02-2009, 07:34 PM
thats the only thing i would change, that galv steel will eat into your aluminum, just grab a bigger fly and throw it in there. great plan tho.

08-03-2009, 11:07 PM
i did

08-05-2009, 12:34 AM
When are you going to have your car back on the road man? I want to know how this turns out so i can try it for myself. Although i plan to do a full port and polish with port match. Im working on a monster of a build im still in the planning stages right now though.

08-05-2009, 06:50 PM
as soon as i get a new rebuilt head, the first one had valve problems.

08-05-2009, 08:59 PM
oh alright. Im looking forward to seeing some results. Im in the process of finding a head i can work on. I have a buddy who just got back from wyotech and is working on porting and polishing his spare head for his civic so it seems like a pretty easy yet time consuming project.

08-05-2009, 10:52 PM
sounds like fun, i have been doing all kinds of upgrades to my car in my spare time, today i polished my valve cover.

joe's gt
08-06-2009, 02:16 AM
Sweet man. What did you use to polish it?