MODIFICATION , THROTTLE BODY ( 4G Accord / Ford 65mm + B16 Manifold / TB Spacer )

PORTING STOCK TB / OVERBORE 4G TB

Well I gave it a shot and bored out the TB I felt some defante gains and will probably experiment with another soon to see the max I can go. Right now this brings the mods list to (not including appearance)

Bomz /AEM custom CAI K&N Filter
MSD 6Al
Accel 14001 Super Coil
Magnecor Wires
NGK Irridium IX Plugs
Colt Cams Triflow Cam
(Specs)
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Duration/lift:
Intake 1 260/384
Intake 2 270/384
Exhaust 274/402
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DC Sports Headers 4-2-1
Highflow cat
2.25 Dynomax mandrel exhaust
Cosmo Racing FPR
High Flow Fuel injectors.
Bored Throttle Body
Centerforce Dual Friction Clutch
Hyper ground made with monster XL wire.
92 Civic strut bar custom fitted

Sweet I can't wait to get my custom intake manifold done for my Weber. I've been working on it every now and then at school with their spendy alluminum de-burring bits :D

Have u ever ran it?Do u know how much hp ur putting down.

Who are you talking to?

Starter I believe.

no I have never ran it or dynoed it I would love to. All I know is every one who rides in it is very impressed with it's ability

and A20A1 I love the tequila kitty avitar

I'll agree, it definitely helps. Not an extreme amount, but you can feel the increase after the bore/polish is done.

So what do you guys use to polish it. I have mine pretty smooth but not with the polished finish.

Quote:

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Originally posted by Justin86
So what do you guys use to polish it. I have mine pretty smooth but not with the polished finish.

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Dremel. Got all kinds of attachments for it :)

and the bore, do you do it before and after the butterfly?i did mine but i think i can go bigger yet.... what size did you go to?

yes before and after I stopped around 63mm It was a bit of an experiment I am probably going to try more after the intersesion

Well I used the dremel bits on my dril press but I can't find any bits that will produce the polished look. I'm pretty close with using fine sadpaper but you can still see little scratches all over it.

Quote:

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Originally posted by Justin86
Well I used the dremel bits on my dril press but I can't find any bits that will produce the polished look. I'm pretty close with using fine sadpaper but you can still see little scratches all over it.

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You need a wire brush, polishing stone, felt polish discs, the polish compound and a lot of elbow grease.

If I can just find that stuff.

look in almost any hardware store

That is where I looked and they just had the bacis bits, I should check to see if they can order me the bits

hey u bored it out to 63mm on the intake side on the manifold side or what?

that reply seemed like u did both sides, but what did u do with the butterfly then? or did it look like >-<

currently the butterfly is the same I am waiting untill I have more time to get a new one

i tried doing something similar to that. I dont see how you measured it... how did you any way did you have a micrometer? Also my throttle has been sticking after i took it off any clues?

Boring the throttle body on a stock or almost stock Honda engine seems to be a wasted time.

Here's a quote from "How To Build Honda Horsepower, Dyno-Verified Results" by Richard Holdener.
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"The stock throttle body from a B16A motor flows almost 600 cfm. To give you an idea how good the stock throttle body is, that amount of airflow will support right near 400hp.
...
Sometimes, bigger throttle bodies do add power, but the increase is generally small and the motor in question needs to be really healthy. Your stock D16Z, or even a high-winding B16A, will not likely benefit from the installation of a larger throttle body. How do I know? Dyno tests were run on both motors comparing stock and over-sized (64.5 mm) throttle bodies with no measurable change in power."

Quote:

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Originally Posted by foobari

Boring the throttle body on a stock or almost stock Honda engine seems to be a wasted time.

Here's a quote from "How To Build Honda Horsepower, Dyno-Verified Results" by Richard Holdener.
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"The stock throttle body from a B16A motor flows almost 600 cfm. To give you an idea how good the stock throttle body is, that amount of airflow will support right near 400hp.
...
Sometimes, bigger throttle bodies do add power, but the increase is generally small and the motor in question needs to be really healthy. Your stock D16Z, or even a high-winding B16A, will not likely benefit from the installation of a larger throttle body. How do I know? Dyno tests were run on both motors comparing stock and over-sized (64.5 mm) throttle bodies with no measurable change in power."

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i think you are wrong. i don't know how you do your dyno runs around there, but here in the US. even slight overbore will give you increase in power.
if you read sport compact, import tunner, turbo & high performance or honda tunning they all recomend bigger throttle body for stock engine as one of the easiest way to pick up a few HP at middle and upper RPM range. i agree the power gains are small but they are there.
i think the last time sport compact magazine did dyno run with bigger TB they gained about 3-4 hp at upper band on B16 motor.

Quote:

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Originally Posted by shepherd79

i think you are wrong. i don't know how you do your dyno runs around there, but here in the US. even slight overbore will give you increase in power.

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I'm not saying that boring the TB does nothing, I was just quoting the book By Richard Holdener, who BTW does all his dynoing on DynoJet machines in the US.

http://images.amazon.com/images/P/18...1.LZZZZZZZ.jpg

In the book he states on several occasion, that according to his dyno tests, boring the TB on stock motor yielded no (significant) power gains. The best numbers seem to be on a B20/B16A Hybrid (200hp to the wheels), where he got max +2.8hp with a bigger RC Engineeing throttle body, and a Supercharged D16Z 1.6 VTEC (153hp to the wheels) where the bigger Holley Throttle Body gave out huge 6.1hp.

So ok, I guess I was too prompt with my "waste of time" comment. If you have en engine with mods on it, at least it won't hurt you to bore the TB out.

ok here is the deal if you bore out your throttle body you will see gains of around 2 to 15 hp nothing to big but for a 3gee every hp helps i dosent matter if it is 1 hp or 20 its not a old street rod its a frickin honda so we need all we can get the only thing you will see is a bit more accel thats about it and yes you will get 2 to 15 hp i live 5min. from a race shop they have a dyno we bored a civic si no mods only the thottle body and thats what we got but you should doo it little by little and take your time

Quote:

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Originally Posted by stolenracer

thats about it and yes you will get 2 to 15 hp i live 5min. from a race shop they have a dyno we bored a civic si no mods only the thottle body and thats what we got but you should doo it little by little and take your time

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Ok, sounds really interesting! What do you mean by "2 to 15hp", is this increase measured in one run (like +2hp@3000rpm and +15hp@6000rpm), or do you mean 2 to 15 hp depending on the bore? How did you bore the TB? Did you just bore it (with a sort of venturi), or did you also re-blade it?

hey sweet!!
so did ya get that idea from me?? did I inspire you to do soo...haha
i'm glad you like it..i love mine:)

depending on the bore i would strongly recomend useing a caliper to determin how much you shave off the tb thats the easyest way to figuer out the diamiter (i cant spell )

Unfortunately that is yes with a but. I got a 4th gen accord rc bored out TB today it bolts up wonderfull but I am having issues with it. When I first start my car it runs wonderfull but then it starts to do some weird things.. When I depress the clutch the engine stays reved about the same place it was when I hit the clutch and then when I start it idles very low about 200 I have played with the idle screw a little and am not resetting the ecu do you guys have any thoughts.

sounds like vacuum leak somewhere after the car warms up.

OK I reset the ecu I have checked for leaks cannot find any here is what it is doing now. When I hit the clutch it goes to about 2000 then after I stop for a sec it goes down and idles perfectly. I have yet to get any codes and I am thinking it may be the map sensor. I am going to try to get e J/y one from a 4th gen and see if I can get it to work. But tonight I am going to try a couple more things

you are talking about just the TB or the top half part of the intake manifold itself?

I think its because of the overbore on the already big TB of the 4th gen. Does the linkage get stuck? Mine did that and it turned out to be lotsa gunk inside the TB itself where the butterfly mates to the TB. A pic would be cool :)

All the ports on the TB line up?

I an going to have to check the port matching I believe it is close I havent really had time off from school but when I tried to adapt a civic one I ported the pletnum. But all the other ports line up the gasket number is even the same.


I don't think anything is getting stuck I cleaned everything. I am still going to hit the J/Y on thursday and see how it hooked up. It runs very well now except the high idle for a sec untill I stop. It is defantly a nice power gain

Quote:

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Originally Posted by 1988starter

I an going to have to check the port matching I believe it is close I havent really had time off from school but when I tried to adapt a civic one I ported the pletnum. But all the other ports line up the gasket number is even the same.


I don't think anything is getting stuck I cleaned everything. I am still going to hit the J/Y on thursday and see how it hooked up. It runs very well now except the high idle for a sec untill I stop. It is defantly a nice power gain

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you are talking about port matching so i believe you are talking about the whole intake manifold??? cant wait for a pic bro. This is just friggin coool. :) :cool2:

Great idea starter! im gonna put one on my lx :rolleyes:

read the title SMUFGUY... its says throttle body, so i think he means the whole intake manifold?? nope... he just won an oversized TB on ebay and thats what hes talkin about

Travis

Quote:

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Originally Posted by dXsquared

read the title SMUFGUY... its says throttle body, so i think he means the whole intake manifold?? nope... he just won an oversized TB on ebay and thats what hes talkin about

Travis

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Yup you got it and it is a direct fit I just think I am having map sensor problems. Altho I did take it on a 45 minute trip yesterday and had no problems except the weird idle thing and when I come to a full stop it goes right back to normal. I loved the feel on the express way. After idle settles down it idles low and very smooth. The bore is maxed at 62 mmin the front and 58.5 in the back

Quote:

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Originally Posted by dXsquared

read the title SMUFGUY... its says throttle body, so i think he means the whole intake manifold?? nope... he just won an oversized TB on ebay and thats what hes talkin about

Travis

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thats what i thought, but the port matching kinda threw me off. :( a TB does not have ports only the end of the runners have em. Unless they are talking about different ports.

I ment port matching the back of the TB to the pletnum and the fast idle ports tothe pletnum but the fast idle ones match perfectly. I honostly think it is a map sensor issue.

hey i just got a JG bored throttle body from a member here, and it does a similar thing, if i rev to 3000, it will idle at 3000 pretty much from then on. so if i shift early i will slowly pick up speed until im around 3000, its obnoxious

also i got a pgmfi light which was throwing me a TPS code....
so i am gonna snag another TB with known good TPS and try that.

i wonder WTF it could be thats doing that.

tangent:
also i have since put on my stock TB, and now i get a whistle sound when im part throttle. its fun to see how long i can sustain the sound, but im pretty sure its not a vaccum leak, my friend has the same setup on his civic si, and it sounds VERY similar, something to do with MSD, and CAI, but it makes a strange sound. the reason i think its msd related is because on his car the MSD was bolted down on the passenger side, and the whistle came from there, on my car the msd is mounted right behind the intake manifold, and thats where the whistle comes from.
it wont wistle just revving, so im having a really hard time isolating the noise.

Yea if I rev it to 3K then hit the clutch it will stay there. I am going to try to switch the TPS sensor with the one from my tb and see if it helps. BTW check your intake piping and make sure it is tight that is what usually makes a whistle.


Side note I don't feel any laging at any RPM but I will continue to figure out this problem because I love the gain I feel from the TB.

its all tight, its bizzare that it never happened before. also i have had it leak and its a different sound slightly... this whistle only happens for a few seconds under sustained part throttle.... if i gun it its just a chirp when i shift.

anyway it doesnt bother me, and the car is running strong so i will live with it. :)

make sure to post back if you fix the RPM problem.

Another thing I noticed it that the max bore possiable on a 4th gen TB is much bigger that that of an 86 or 87 accord but the same as a 88 TB at least when I measured your JG one vs my RC one and JG is known for going to the max bore

did i buy that TB off of you??? lol i just know the email addy of the person, i forgot who started the thread lol. :)

yea its the MAP sensor. I have heard they will act up with bored TB for some reason.

Quote:

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Originally Posted by bobafett

did i buy that TB off of you??? lol i just know the email addy of the person, i forgot who started the thread lol. :)

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No you bought it from B20a turbo but I bought it from him first and returned it because it would not fit my 88 and the TPS on it is different from mine

I have a similar problem with my car wven with the stock TB. The only difference is that it will idle at 1100~ 1200 before dropping to 850. it's not that bad

Quote:

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Originally Posted by Justin86

yea its the MAP sensor. I have heard they will act up with bored TB for some reason.

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Any clue on how to fix it. Or how to reset mine

First off sorry to the mods if you feel I should have combined this with my other thread BUT I thought it deserved it's own because I now have pics.

The old thread can be found HERE

1) OK IF ANY ONE HAS A 4TH GEN VACUME DIAGRAM PLEASE POST IT.
Ok here is the deal I have the car running it is a hella lot faster and real easy to do BUT the idle is very weird.
2) When I go into nutral or depress the clutch the engine revs to about 2k untill I stop for a sec and it settles down I think it may have to do with the larger vacume line not being used for what it is soposto I am going to diable it and try some stuff tomorrow.
3) Any way I believe the map sensor is getting a weird signal with the new TB so if you know how to reset it or change it please tell me. Other than that as soon as I am able to hit the J/Y I am going to pick up a 4th get MAP sensor and see what I can do.


any way here are the pics (YES I KNOW MY ENGINE BAY IS DIRTY IT IS WINTER HERE LEAVE ME ALONE)
The front of Both TB's
http://www.geocities.com/geezpict2/tbody/top.txt
A side view of the back
http://www.geocities.com/geezpict2/tbody/sback.txt
A top view of the back
http://www.geocities.com/geezpict2/tbody/tback.txt
Not mounted TB colant bypass
http://www.geocities.com/geezpict2/tbody/notb.txt
mounted with out nuts and new vacume line running in (red one)
The vacume port is larger than the 3rdgen one
http://www.geocities.com/geezpict2/tbody/bypass.txt
finally all mounted up ready to go
http://www.geocities.com/geezpict2/tbody/mounted.txt

I can email you a scanned copy of vacuum/emssions diagram for 90 Accord if you like

sweet that will help please send it to [email protected]

on its way via hotmail...subject heading on email will tell you its from me

thanks man it helps I think I will hit the J/Y and see about a 4th gen MAP hopefully monday

No prob, hope it helps, hope the image is ok,if not let me know and I'll try again at a diff. res.

it's a little blury but I can handle it. Would you happen to have one that shows the intake manifold and where all the lines connect to

the image has intake manifold on it,its pictured horizontally of the engine head to the right,...but maybe image is to blurry to see it....I'll try another scan

sent another,....how is it?

Why not make this a project... I can send it up to project central.

Quote:

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Originally Posted by A20A1

Why not make this a project... I can send it up to project central.

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If you want to feel free

and crunz the second one was a lot better thanks.


OK todays update I took of both TB's and inspected them The only real difference seems to lie in the upper right fast idle port. As you can see in the top pict the 4th gen one has a slightly mishapen edge that has a hole in it this hole goes to he idle screw. the third gen one has the same thing but is is located a bit farter down. I believe the final key resigns in getting a 4th gen map sensor.

OK I took a look at my friends 91 accord all the lines are exactly the same so I think monday i will hot the boneyard and pick up some stuff

OK here is the deal I have been working on upgrading to a 4th gen TB with somee good luck today I picked up a 4th gen map sensor. I also got some extra plug halves so I would not have to splice anything. All I can say is wow what a huge difference in power and I still have the stock TB on.

There is this sigh near my house coming off my street the besi I have been able to do going past it till today is 70. I was taking the car for a test run I thought I felt more power as soon as I left the driveway. Well on my first try pased the sign at 72 then 73 on the second run and consistently hit 73. Well I thought I would share I don't have it mounted permantly yet just kinda half mounted it is not going any where but I want to make a housing or put it inside the box. Pics later tonight and hopefully testing the new TB out soon.

sounds like a good mod. have you measured to see how much bigger it is over the stock TB?

Well I kinda home brewed a bored out TB a bit ago with a grinder that one is 60 mm in the front and I think 55 in the back I will ckeck once I take it out again but the new one goes from 62-58.5 and it has a larger plate check out pics in project central.

ok here they are the adapter and the initial install before I make a bracket
http://www.geocities.com/geezpict/mapsensor/adapter.txt
http://www.geocities.com/geezpict/ma...r/sensorin.txt

hmm i may have to try that.

Let me get this straight. You have the 3G, bored out TB in right now with the 4G map sensor, right?

No I have a 3g and i am tring to use a 4g bored TB (check project central)but I was having issues with idle being a bit high before I stopped (map sensor problem) so I decided to get a 4g sensor. I will be installing the 4g TB tomorrow after I take a long trip back and forth to school to make sure I have no problems. Altho my initial test drives proved to be excelent.

I should mention that I did bore out my 3g TB but only with a dremmel and never got a bigger plate and the 4g TB has a larger plate and bigger bore

Aha! Thanks.

awesome! i will have to look into that shit! ;)

good report starter.

hum maybe I need to take a trip to the j/y. :)

that is wicked man. I was on that thread before. Anyway, can u explain what u exactly did and what and where actually u pulled the parts from? It would be awsome.

U did not use the 4g fast idle valve did you? I think u used the 3g valve right?

OK I pulled the map sensor from a 4g and got the female ends of the plug from both a 4g and a 3g. Spliced the two together (same color code) and hooked the 4g sensor like I would a 3g sensor. and no I am still using my 3g fast idle

Any problems? or is running good? Cause I'll switch mine over to a 4g TB this summer if it works

No problems with the 3rd gen TB but I installed the 4g and noticed the same weird idle thing just a bit less sever I am going to try bringing it to school today

first, you have look at throttle position sensor. it may be diff, so when your computer gets the reading it is all wrong.
second, this mod is for 88-89 EFI accord only.
86-87 have single stage manifold and one TB bolt is diff.
i went to junk yard today and pulled the 4G TB and compared to 3G TB, man it was off. so i have to shave the 4G TB to fit on 86-87 intake manifold.

I am currently using my 3rd gen tp sensor

let me know how that goes Alex. I'm picking up an f22 TB this weekend.

Well same deal but tommorrow I get paid so maybe I will pic up a gauge and possiable a vacume limiter or to

i compared the F22 and A20 TB, and they are the same.
the diameter on the outside is 2 3/16" so you won't gain a thing unless you have overbored TB.
i am working on the Map sensor tonight i will let you guys know if there is power diff tomorrow.

Quote:

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Originally Posted by shepherd79

first, you have look at throttle position sensor. it may be diff, so when your computer gets the reading it is all wrong.
second, this mod is for 88-89 EFI accord only.
86-87 have single stage manifold and one TB bolt is diff.
i went to junk yard today and pulled the 4G TB and compared to 3G TB, man it was off. so i have to shave the 4G TB to fit on 86-87 intake manifold.

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That's what I figured, but I plan on replace the TB along with a few other pieces this summer... so might as well add some power to it at the same time

so I can get a 4g TB to fit direct? hhmmmm... interesting :jaw:

it won't fit on 86-87 acord direct, you will have to do some fabrication work.
but it will fin direct if you have 88-89 accord

Ok not to sound stupid but where is the map sensor, and what does it do¿

so has anyone figured out how to reset the sensors for the bored 3rd gen TB, having problems with check engine light and the idle sticking too....

anyone? :sadwave:

what size butterfly did you put into the port? Maybe you can try and rotate the throttle position sensor some, just make sure you mark the stock position before removing the headless bolts securing the sensor to the TB, and get new bolts to take it's place.

so in order for the 4g TB to be installed it has to be port matched and a optional 4g map sen?

to get it to fit on an 88 or 89 nothing has to be done but to get it to work properly I am not sure I still have yet to find time to work on it.

im talking about an 86

ok even though im in a carbed 87 i often consider swapping to efi i would like to know whats up with this mod is it a hp increase or what? has anyone got it working correctly? if i end doing the swap id like to be able to get the 4gee tb from the get go see if i know its worth it meaning its gonna be faster then a webber carb i can get all the sensors i need from a 4gee and a manifold ect from a 3gee 88-89 efi . it would probably cost about as much as a webber. so let us all know what the deal is ide like to do this soon.

Well I never did finish the project because I am going to sell my 3g but I am going to sell my 4g over bore tb robably on ebay with a buy it now at 160 as that is what these rare things tend to go for

im getting sean to install my 4G on to my stock P&P intake that is also port matched with my head and the TB as we speak. hopefully ill get it all back by next weekend :D

So...what happened?? somebody sold they're car, did nobody else finish the project?

Quote:

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Originally Posted by Civvy

So...what happened?? somebody sold they're car, did nobody else finish the project?

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I sold my car but I still have the TB I want 150 if you want it

its about time i carried my weight around here.

1)get an OEM ford/lincoln/mercury 4.6/5.0 t/b.
2)get the tps/wires( both look for 0.x v/5v)
3)wire it up identical to the honda one(same positions,not colors)
4)drill out the holes on the ford t/b to match whatcha need (i got 2/4 bolts :ugh: ).
5)PORT MATCH!-this is manditory
6)re-route t/b vacuum lines to the manifold
7)bypass ALL cooling lines on the manifold
8)spend 30 seconds adjusting the linkage
9)seal it up and your done!

NOTES:
-You have to slot the tps and adjust clockwise.
-i have no idle problems period, but i have no idle/emisson stuff
-i did have a VERY noticeable gain with this in COMBINATION with headwork and the b16a mani.
http://i2.photobucket.com/albums/y39...i/S2010010.jpg
http://i2.photobucket.com/albums/y39...i/S2010009.jpg
http://i2.photobucket.com/albums/y39...i/S2010008.jpg

http://i2.photobucket.com/albums/y39...i/S2010007.jpg
http://i2.photobucket.com/albums/y39...i/S2010002.jpg
http://i2.photobucket.com/albums/y39...i/S2010001.jpg

its actually upside down compared to a ford

lol nm!

Im running a Power-plus B16a manifold. They are on ebay all the time for 150-200 bucks

What manifold are you using that can be impotant.

Quote:

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Originally Posted by hondamanlxi

lol nm!

Im running a Power-plus B16a manifold. They are on ebay all the time for 150-200 bucks

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So the B manifold doesn't have the 2 air bypass holes like the stock A manifold. I wonder if the TB would still work with a stock A20 manifold or would the B series upgrade be almost required. ???


Yeah I deleted my earlier post cause I didn't want to get in the way of the how-to... just a heads up to everyone... all replies to this thread not relavent and not useful will be deleted when this becomes a how-to. part of the reason I'm editing this post instead of making new ones.

looks like b16 (b series) manifold ;-)

im not sure what you mean by air bypass holes, but i was running a b series t/b on a stock mani with all vacuum/idle control shaved off. Please note that this t/b doesnt have any vac ports period.

Quote:

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Originally Posted by A20A1

What manifold are you using that can be impotant.

So the B manifold doesn't have the 2 air bypass holes like the stock A manifold. I wonder if the TB would still work with a stock A20 manifold or would the B series upgrade be almost required. ???

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In fact it does. It needs those 2 holes for the Idle Air Control Valve and the Fast Idle valve. The A20A and B series intake manifold share the same Throttlebody design.

The way the FORD Throtthebody works, it looks like you will run into idle problems for sure. You will have to work something out for the Idle valve.

Also, the Map sensor must be re-routed somewhere else

Yeah I was wondering if the holes where there or not...

On the throttle plate, it has a hole drilled in it... thats something I've seen on carb choke plates as well as throttle plates.