Project Fat Nikki

t_g_farrell · 02-15-2012, 11:40 AM

I've procured an 85 nikki and intake manifold from pullapart for some fun.
My goal is to hog out this nikki to the best of my abilities so that it can be used in
place of my current Dellorto setup. I have no compelling reason to do this, the
Dell works great. I just thought it would be fun to do. It will initially go on my
stock port 12A.

I'm cleaning and disassembling right now and will get pictures up as I go along
making the various mods. I know I could get a sterling (maybe) or from SR
Motorsports but I want to do it myself.

So I'll post my detailed plan for the modifications to be done. Please feel free
to post up anything I may be missing or can do better or have first hand
knowledge about that can help me out. In return I promise to deliver lots
of details and pictures as I go along.

Heres the plan. I've numbered each step uniquely and grouped then logically
by component to make discussions easier. If nothing else I hope this helps
anyone else contemplating hogging out their nikki.

AIR HORN mods

done A1. remove choke plates and rod and seal up holes

done A2. remove choke diaphram and brackets, plug holes

done A3. dead head fuel inlet for now. Just cap with bolt and gasket. Keep return and other gasket just in case.

kept A4. remove air vent solenoid, plug with bolt
But disconnected

done A4. remove alt. compensator, plug holes

MAIN BODY mods

done M1. remove dashpot and bracket, plug holes

done M2. remove secondary diaphram, plug holes

done M3. remove TPS

done M4. Drill out AP jet, top center and top 2 holes to .5mm

skipped M5. Drill out AP nozzle to 0.050 "

done M6. Double up gaskets on AP diaphram

done M7. Add extension to AP pump arm.

done M8. Pull primary and secondary booster venturis and cut extra arm off and smooth remainng arm
also polish up inside each venturi to clean up and smooth it out.

done M9. Mill down primary and secondary venturis a little bit

done M10. Drill out fuel and air jets. Or buy holley air bleeds for fuel and only drill air jets.
- only drilled the primary fuel about 1mm or so.

THROTTLE BODY mods.

done T1. Hook up mech secondaries

done T2. strip down linkages to bare minimum

done T3. cut half of secondary shaft away, use shorter small cap hex bolts to attach butterflys

skipped T4. use small cap hex bolts to attach primary butterflys.

INTAKE MANIFOLD mods

done I1. remove butterfly and rod, fill holes

done I2. cut channel between rear primary and seconday opening

I3. install ACV blockoff plate

I4. cut or plug pipe off of the back of the intake

done I5. plug or cutoff extension off rear of intake
Plugged with JBWeld

Rich@SR · 02-15-2012, 01:17 PM

Let me know if you run into any road blocks. I can also do the machining of the venturi's for you if you can't get the proper equipment yourself. Keep us posted!

t_g_farrell · 02-15-2012, 01:29 PM

Thanks for the offer. I'll keep it in mind.

I'm amazed at how many small tweaks that are needed to do this. Anyone
modding nikkis like yourself and sterling are really earning your money.

Its a lot of small details, thats why I split it up into the 4 major areas. I'm
going to do each set before moving onto the next.

Rich@SR · 02-15-2012, 02:55 PM

Quote:

Originally Posted by t_g_farrell

Thanks for the offer. I'll keep it in mind.

I'm amazed at how many small tweaks that are needed to do this. Anyone
modding nikkis like yourself and sterling are really earning your money.

Its a lot of small details, thats why I split it up into the 4 major areas. I'm
going to do each set before moving onto the next.

Yep! DETAILS DETAILS DETAILS! Especially polishing the booster venturi's. Takes me hours to do them. Anyway if you get hung up or just want to bounce ideas hit me up. 954-288-4508. Keep us posted with pictures.

mattallac · 02-15-2012, 05:16 PM

T G FARRELL from the last thread it looks like you'r on the right track now.Lots of guys modify the stock carb with great results good luck

t_g_farrell · 02-16-2012, 09:25 AM

No real progress to report. I chem dipped the major pieces but I need to get
some carb cleaner and go at it with a brush and elbow grease this weekend.
I don't have a parts washer so I have to do it the old fashion way. I'm not in
a hurry so that ok.

I'll be ordering the GP Sorensen carb kit as well when I pick up the carb cleaner.
Once its all clean I'll take before shots of everything and then start modding
the carb from the top down.

t_g_farrell · 02-21-2012, 12:23 PM

Well the carb cleaner I had sucked. It was from advancezone etc and it was
so safe you could water your plants with it. I did some research on the net
and I found that what I wanted was lacquer thinner. It has all the best
ingredients like toluene, acetone, etc.

So I soaked the carb and intake in this yesterday while I was doing some yard
work and they cleaned up pretty good with no real scrubbing. I still want to
take a brass wheel to it all for final clean up, plus I'll reuse the thinner when I
pull the jets as well. No pics yet. I'll post them after I wire brush it all and
before I pull off any jets or venturis.

Got the rebuild kit in and it looks complete. Now I just have to drop by HF
tp pick up some indexed drills and a few other odds and ends for my dremel
supplies.

Kentetsu · 02-24-2012, 10:22 PM

Not a job for those looking for quick rewards.

I admire your patience, and look forward to seeing your mod work...

.

t_g_farrell · 02-25-2012, 09:15 AM

Quote:

Originally Posted by Kentetsu

Not a job for those looking for quick rewards.

I admire your patience, and look forward to seeing your mod work...

.

Shhh. Just don't tell Ray about it.

t_g_farrell · 02-27-2012, 12:39 PM

Heres some pics of the carb partially dissassembled and after hitting it with some lacquer
thinner to clean it up. I haven't done any other cleaning yet. I plan on using a home
made soda blaster with my compressor to do the final cleanup. That will be a lot of
fun! This carb was really easy to pull apart. Can't tell if its ever been opened before
but it seems pretty unmolested. I'd call it a good buy from pull-a-part so far.

So heres the pictures, top and bottom view of each component from the top of
the carb down to the intake manifold.

Already remove the choke assembly and few other bits.

ROTORX7Holly · 02-27-2012, 01:41 PM

Tim I can't believe Ray got to you. Ray will never find this thread over here. You'll have to show it off at an OGTA when your through.

t_g_farrell · 02-27-2012, 02:31 PM

Quote:

Originally Posted by ROTORX7Holly

Tim I can't believe Ray got to you. Ray will never find this thread over here. You'll have to show it off at an OGTA when your through.

Thats the idea Holly

I plan on unvieling it at some event where Ray and
I meet up. I won't have it done for the March OGTA, so maybe for DGRR or Mitty.

Actually, I want to do this so I have 2 carb setups to play with when I build
another motor. I figure I can keep the Dell which is already tuned to a stock
port 12A very well on the side and put this fat nikki on and tune it as well.
That way when I build a new motor I have lots of options for getting it tuned
and ready to roll. Also the nikki was cheap and its very cheap to do the work,
you knows us old guys, we like cheap.

The new engine will be some sort of ported 12A, haven't decided
details yet, just have a couple parts engines sitting in the garage apart at the
moment. Heres my thread on that.

t_g_farrell · 04-01-2012, 07:17 PM

I channeled the intake manifold and just have to plug up a hole where the
rod for the butterfly come through. I also clean up the intake a bit but I want
to media blast it before final assemply. I may clear coat it to keep it nice looking.

Did some work on the throttle cable bracket and removed some things to simplify
it a lot. No pic of that yet.

Worked on the throttle body but had a hard time getting the secondary butterfly
screws out. I tried heat and that didn't help, so I'm soaking in PB blaster and
will give it a go later this week. Any tips on removing those screws would be
great. Hate to have to drill em out.

Also worked on the carb body some. I trimmed the arms off of the primary and
secondary venturis and polished them a bit. Also ground down and polished
the chokes as well. Didn't ream them too much but I may do some more later.
I haven't shortened the oil inject tubes but I did pull them out a bit as they
were almost right up against the small center venturis in the primaries.

GoopyPerformance · 04-02-2012, 07:50 AM

Keep up the good work guys..

The Stock nikki s a great carburetor and we need more folks with solid know-how on these carbs for street, race and blow-through projects.

Rich@SR · 04-02-2012, 12:55 PM

For the butterfly screws:

#1. Use a screw driver that is the right size.
#2. Place the screw driver on the screw and give the screw driver a good tap with a hammer. This not only sets it in the screw head but also give the threads a little shock to knock them loose. You may have to repeat this a few times, but I've had 100% success with this.

I automatically do this for all the carb screws just to make sure I don't strip any, works like a charm.

02-15-2012, 01:29 PM	#3
t_g_farrell Waffles - hmmm good Join Date: Aug 2008 Location: Huntersville, NC iTrader: (0) Posts: 757 Rep Power: 0	Thanks for the offer. I'll keep it in mind. I'm amazed at how many small tweaks that are needed to do this. Anyone modding nikkis like yourself and sterling are really earning your money. Its a lot of small details, thats why I split it up into the 4 major areas. I'm going to do each set before moving onto the next. __________________ 1980 GS stockport, Fat Nikki, RB Dual Facetfuel pumps, Holley regulator, RB Street port exhaust, 2GDFIS, MR2 MK I electric fans, 2G strut bar, relayed fans, lights and fuel pump, LEDs Project Fat Nikki Budget 12A rebuild Video setup < $30.00

02-16-2012, 09:25 AM	#6
t_g_farrell Waffles - hmmm good Join Date: Aug 2008 Location: Huntersville, NC iTrader: (0) Posts: 757 Rep Power: 0	No real progress to report. I chem dipped the major pieces but I need to get some carb cleaner and go at it with a brush and elbow grease this weekend. I don't have a parts washer so I have to do it the old fashion way. I'm not in a hurry so that ok. I'll be ordering the GP Sorensen carb kit as well when I pick up the carb cleaner. Once its all clean I'll take before shots of everything and then start modding the carb from the top down. __________________ 1980 GS stockport, Fat Nikki, RB Dual Facetfuel pumps, Holley regulator, RB Street port exhaust, 2GDFIS, MR2 MK I electric fans, 2G strut bar, relayed fans, lights and fuel pump, LEDs Project Fat Nikki Budget 12A rebuild Video setup < $30.00

02-21-2012, 12:23 PM	#7
t_g_farrell Waffles - hmmm good Join Date: Aug 2008 Location: Huntersville, NC iTrader: (0) Posts: 757 Rep Power: 0	Well the carb cleaner I had sucked. It was from advancezone etc and it was so safe you could water your plants with it. I did some research on the net and I found that what I wanted was lacquer thinner. It has all the best ingredients like toluene, acetone, etc. So I soaked the carb and intake in this yesterday while I was doing some yard work and they cleaned up pretty good with no real scrubbing. I still want to take a brass wheel to it all for final clean up, plus I'll reuse the thinner when I pull the jets as well. No pics yet. I'll post them after I wire brush it all and before I pull off any jets or venturis. Got the rebuild kit in and it looks complete. Now I just have to drop by HF tp pick up some indexed drills and a few other odds and ends for my dremel supplies. __________________ 1980 GS stockport, Fat Nikki, RB Dual Facetfuel pumps, Holley regulator, RB Street port exhaust, 2GDFIS, MR2 MK I electric fans, 2G strut bar, relayed fans, lights and fuel pump, LEDs Project Fat Nikki Budget 12A rebuild Video setup < $30.00

02-24-2012, 10:22 PM	#8
Kentetsu RCC Contributor Join Date: Feb 2008 Location: Grand Rapids, Michigan iTrader: (1) Posts: 530 Rep Power: 17	Not a job for those looking for quick rewards. I admire your patience, and look forward to seeing your mod work... . __________________ "Learn from the past, or it will become your future...." '85 GS 12a + LSD/Sterling carb/Respeed coilovers/Respeed front swaybar/Respeed adj. rear spring perches/Illuminas/Bilsteins on rear AutoX vids @ http://www.youtube.com/user/Kentetsu1

02-27-2012, 12:39 PM	#10
t_g_farrell Waffles - hmmm good Join Date: Aug 2008 Location: Huntersville, NC iTrader: (0) Posts: 757 Rep Power: 0	Update for pics Heres some pics of the carb partially dissassembled and after hitting it with some lacquer thinner to clean it up. I haven't done any other cleaning yet. I plan on using a home made soda blaster with my compressor to do the final cleanup. That will be a lot of fun! This carb was really easy to pull apart. Can't tell if its ever been opened before but it seems pretty unmolested. I'd call it a good buy from pull-a-part so far. So heres the pictures, top and bottom view of each component from the top of the carb down to the intake manifold. Already remove the choke assembly and few other bits. __________________ 1980 GS stockport, Fat Nikki, RB Dual Facetfuel pumps, Holley regulator, RB Street port exhaust, 2GDFIS, MR2 MK I electric fans, 2G strut bar, relayed fans, lights and fuel pump, LEDs Project Fat Nikki Budget 12A rebuild Video setup < $30.00

02-15-2012, 11:40 AM	#1
t_g_farrell Waffles - hmmm good Join Date: Aug 2008 Location: Huntersville, NC iTrader: (0) Posts: 757 Rep Power: 0	Project Fat Nikki I've procured an 85 nikki and intake manifold from pullapart for some fun. My goal is to hog out this nikki to the best of my abilities so that it can be used in place of my current Dellorto setup. I have no compelling reason to do this, the Dell works great. I just thought it would be fun to do. It will initially go on my stock port 12A. I'm cleaning and disassembling right now and will get pictures up as I go along making the various mods. I know I could get a sterling (maybe) or from SR Motorsports but I want to do it myself. So I'll post my detailed plan for the modifications to be done. Please feel free to post up anything I may be missing or can do better or have first hand knowledge about that can help me out. In return I promise to deliver lots of details and pictures as I go along. Heres the plan. I've numbered each step uniquely and grouped then logically by component to make discussions easier. If nothing else I hope this helps anyone else contemplating hogging out their nikki. AIR HORN mods done A1. remove choke plates and rod and seal up holes done A2. remove choke diaphram and brackets, plug holes done A3. dead head fuel inlet for now. Just cap with bolt and gasket. Keep return and other gasket just in case. kept A4. remove air vent solenoid, plug with bolt But disconnected done A4. remove alt. compensator, plug holes MAIN BODY mods done M1. remove dashpot and bracket, plug holes done M2. remove secondary diaphram, plug holes done M3. remove TPS done M4. Drill out AP jet, top center and top 2 holes to .5mm skipped M5. Drill out AP nozzle to 0.050 " done M6. Double up gaskets on AP diaphram done M7. Add extension to AP pump arm. done M8. Pull primary and secondary booster venturis and cut extra arm off and smooth remainng arm also polish up inside each venturi to clean up and smooth it out. done M9. Mill down primary and secondary venturis a little bit done M10. Drill out fuel and air jets. Or buy holley air bleeds for fuel and only drill air jets. - only drilled the primary fuel about 1mm or so. THROTTLE BODY mods. done T1. Hook up mech secondaries done T2. strip down linkages to bare minimum done T3. cut half of secondary shaft away, use shorter small cap hex bolts to attach butterflys skipped T4. use small cap hex bolts to attach primary butterflys. INTAKE MANIFOLD mods done I1. remove butterfly and rod, fill holes done I2. cut channel between rear primary and seconday opening I3. install ACV blockoff plate I4. cut or plug pipe off of the back of the intake done I5. plug or cutoff extension off rear of intake Plugged with JBWeld __________________ 1980 GS stockport, Fat Nikki, RB Dual Facetfuel pumps, Holley regulator, RB Street port exhaust, 2GDFIS, MR2 MK I electric fans, 2G strut bar, relayed fans, lights and fuel pump, LEDs Project Fat Nikki Budget 12A rebuild Video setup < $30.00 Last edited by t_g_farrell; 04-16-2012 at 12:31 PM..

02-15-2012, 01:17 PM	#2
Rich@SR SR Race Engineering Join Date: Jan 2012 Location: Loxahatchee, FL iTrader: (0) Posts: 81 Rep Power: 13	Let me know if you run into any road blocks. I can also do the machining of the venturi's for you if you can't get the proper equipment yourself. Keep us posted!

02-15-2012, 05:16 PM	#5
mattallac Rotary Fanatic Join Date: Aug 2011 Location: crockett ca. iTrader: (1) Posts: 176 Rep Power: 0	T G FARRELL from the last thread it looks like you'r on the right track now.Lots of guys modify the stock carb with great results good luck

02-27-2012, 01:41 PM	#11
ROTORX7Holly Rotary Fanatic Join Date: Mar 2008 Location: Atlanta iTrader: (0) Posts: 364 Rep Power: 17	Tim I can't believe Ray got to you. Ray will never find this thread over here. You'll have to show it off at an OGTA when your through. __________________ 2004 RX-8 Back in a Rotary again - March, 2010 2005 Mazda3i .. Purchased Aug. 05.. Daily Zoom Zoomed from Apr., 07 to Mar., 10 Original Owner of 93 VR Base, ...SOLD April 20, 2007.

04-01-2012, 07:17 PM	#13
t_g_farrell Waffles - hmmm good Join Date: Aug 2008 Location: Huntersville, NC iTrader: (0) Posts: 757 Rep Power: 0	Update I channeled the intake manifold and just have to plug up a hole where the rod for the butterfly come through. I also clean up the intake a bit but I want to media blast it before final assemply. I may clear coat it to keep it nice looking. Did some work on the throttle cable bracket and removed some things to simplify it a lot. No pic of that yet. Worked on the throttle body but had a hard time getting the secondary butterfly screws out. I tried heat and that didn't help, so I'm soaking in PB blaster and will give it a go later this week. Any tips on removing those screws would be great. Hate to have to drill em out. Also worked on the carb body some. I trimmed the arms off of the primary and secondary venturis and polished them a bit. Also ground down and polished the chokes as well. Didn't ream them too much but I may do some more later. I haven't shortened the oil inject tubes but I did pull them out a bit as they were almost right up against the small center venturis in the primaries. __________________ 1980 GS stockport, Fat Nikki, RB Dual Facetfuel pumps, Holley regulator, RB Street port exhaust, 2GDFIS, MR2 MK I electric fans, 2G strut bar, relayed fans, lights and fuel pump, LEDs Project Fat Nikki Budget 12A rebuild Video setup < $30.00

04-02-2012, 07:50 AM	#14
GoopyPerformance Rotary parts manufacture Join Date: Sep 2010 Location: Stony point NY iTrader: (1) Posts: 170 Rep Power: 15	Keep up the good work guys.. The Stock nikki s a great carburetor and we need more folks with solid know-how on these carbs for street, race and blow-through projects.

04-02-2012, 12:55 PM	#15
Rich@SR SR Race Engineering Join Date: Jan 2012 Location: Loxahatchee, FL iTrader: (0) Posts: 81 Rep Power: 13	For the butterfly screws: #1. Use a screw driver that is the right size. #2. Place the screw driver on the screw and give the screw driver a good tap with a hammer. This not only sets it in the screw head but also give the threads a little shock to knock them loose. You may have to repeat this a few times, but I've had 100% success with this. I automatically do this for all the carb screws just to make sure I don't strip any, works like a charm.