NZConvertible

You can do that but the performance difference is basically nothing on an NA.

BTW, capital letters don't go at the beginning of every word, only the beginning of sentences. That's really getting annoying...

ddub

That's the forum correcting him. When someone types out a post in all caps the forum changes all but the first letter to lowercase.

To solve the problem he just needs to not type his posts in all caps..

bigturbo

So on a t2 with intake, 3" tid pipe and full 3" exhaust would removing the extra butterflies and porting the tb make enough power to be worth taking things apart??? Thats what Im running and everyone on this thread says its not worth it on an n/a what kind of power do people see with a t2 and the above mods??

RX7FROMCAL

Well Being Mines A Supercharged Fc, What Would It Be Then , It Not A Na Anymore.

RX7FROMCAL

thanks everyone for there thoughts, u have answered my question.

Aznplayer911

iTrader: (1)

Basically... if you are FI then i suggest you do it. its not a quick job, but it not that hard either. you'll feel a difference i promise. Do it... its worth it...

NZConvertible

You'll feel the difference with a Turbo TB, but not with a NA one as they work differently

SonicRaT

iTrader: (6)

Well, since the car in question is 'forced induction', it would be beneficial. Just how much? That remains to be seen with the layout differences between the TB before the 'compressor' and after.

NZConvertible

I think you missed my point.

The Turbo TB has a damper that slows the opening of the #2 secondary throttles, so removing them makes a noticable difference to throttle response. On the NA TB (which he has) those throttles are held open all the time so removing them doesn't make any difference to throttle response and only removes a relatively small restriction.

I'm not saying he shouldn't remove them, just that he shouldn't expect to notice anything.

SonicRaT

iTrader: (6)

Oh, sorry NZ, wasn't even referring to your post, just about him asking earlier what his car is 'classified' as, and what to expect/etc from such.

NZConvertible

Ah, I see. It's cool.

totallimmortal

I ported mine and noticed a little bit of high end, nothing crazy but i thought it was worth the work it wasn't very hard

YearsOfDecay

Bad Digicam.... bad digicam

Might as well polish the whole thing while you are at it!!!!

PS.... A die grinder, a 1/2 burr, a 1.5 inch flap wheel, a 1.5 inch felt bullet buff and a dremel tool with a 1/2 bullet buff are your friends when porting a t-body!!!!

Just modded, ported and polished a 20b t-body and polshied the UIM and LIM for KDR....

I did my TII t-body before i did the haltech and BNRIII.. there was a noticeable improvement in response.... now... with the AFM gone and a whole buttload more hosepower... If I had money falling out my *** for dyno time, i'd stick a regular t-body on do several dynos, and then my modded and ported tbody on and see if there were any real HP number differences... But it does feel crisper, that i know from swapping them out.

ScrapFC

iTrader: (5)

I think there are definite gains to be had in the NA TB. I worked mine over and not only found enough power to feel the difference, but I can stay in the throttle for another 500RPM before the power falls off. Throttle response is instantaneous.
I removed the extra throttle and plugged the holes, smoothed and profiled the dividers (left them at full height), profiled the throttle shafts and used shorter countersink screws so the shafts are totally smooth, and knife-edged and polished the butterflies.
The countersink bit I used can be had in any hardware store for about $5 and works in any drill. I also used a die grinder with a carbide burr for shaping and a homemade sandpaper flapper for polish.
I recommend this to anyone who feels they have the skills to do it. I also recommend getting a used TB, modifying it and then installing it both to minimize downtime and so it's not such a big deal if you screw it up.
Free advice, worth what you paid for it...

BlaCkPlaGUE

That looks amazing yearsofdecay, how do you polish it like that? It looks like its been chromed. What tools/supplies do you need?

NZConvertible

I would be very surprised if most of these gains weren't in your head (i.e. the ever-unreliable butt dyno). As I said, these TB's are huge for the output of the engine, so unless you have a highly modded NA engine (and you don't), the actual gains from slightly reducing the restriction of the TB as not going to do much to offset the other restrictions in the engine.

YearsOfDecay

Well,,,, lets see..... sandpaper up to 400 grit, a couple of 1 1/2 inch flap drum sanders in 120 and 240 grit, A die grinder with a 1/2 dia Burr. and at least a 3/4 HP buffing machine with sisal wheels, heavy cutting compound and cotton wheels with white rouge compund. and small bullet buffs for the corners.

oh... and about two hours of your time (an hour after you've done 20 of 'em). (thats just for the outside...

Here's A3D-Illusions's lower control arm that i just did tonight.... Off the subject I know.. but what the hell



Serously though... I really think that there is good merit to porting the throttlebody, especially when you start flowing high boost and at high RPMS

BlaCkPlaGUE

Yea your right, but you need to have the AFM removed to see a real difference. You have to eliminate the bottleneck before the throttlebody before you can push more air through it.

NZConvertible

For a modded turbo, definitely; for a mildly modded NA, no.

Don't forget that you aren't actually "porting" the TB at all, since you still have three stock-sized 45mm bores afterwards. All you're doing is smoothing out the air path to the throttles a bit, not making the TB bigger.

BlaCkPlaGUE

Is there any way to get an adapter to put on a particular aftermarket TB that flows more air? Like if you cut out the three holes on the actual UIM plenum, and bolted on an adapter with two bigger, or one bigger throttle body?

ScrapFC

iTrader: (5)

I agree that the butt dyno is less than accurate for hp numbers, but it works just fine for determining where the power curve lies. Also, when you drive your car every day you get to know it pretty well. I can feel a difference in acceleration depending on whether or not I have a passenger. (It helps having an NA and not a whole lot of power to begin with...)
That said, I did back-to-back pulls before and after I swapped my TB. My "after" run felt exactly the same as my "before" run, (shifted at 7K rpm) so I was disappointed. I was much more pleased when I realized I had been alone before and brought a passenger after. Then I tried it alone and it seemed a bit peppier. More importantly, my shift point moved to 7500rpm and throttle response is now instantaneous. (great for autox!)

NZConvertible

Unless you have a highly modded turbo, it'd be a waste of time. The stock TB is already very big to start with. Guys are making well over 400hp on them, so there's no way the TB is a restriction on an NA engine making less than half that.

I would be willing to bet the at the reason you felt an improvement was because prior to the mod the #2 secondary plates (the ones you removed) were not fully opening the way they should. On NA's those plates should be held fully open any time the engine is warm, and two extra open throttles in an already oversized TB (see above) are going to be causing very little restriction.

I'm glad you noticed positive results, but this should not be considered a typical result from the TB mod on an NA.

jacobcartmill

iTrader: (6)

porting the TB makes about a 10hp gain all across the power band when you're making about 300whp all other things equal.