1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Racingbeat Holley or rotaryshack Weber or unknown 48 Ida

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Old Apr 18, 2017 | 10:43 AM
  #126  
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Originally Posted by chuyler1
Is there a tutorial on changes that need to be made to the intake for the hogged out Nikki?
Not that i know off.
People do portmatch the primary to the intake runner on the engineblock because there is quite an difference in size. I understood that it's to prevent blowback of the mixture in the intake
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Old Apr 18, 2017 | 11:50 AM
  #127  
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Originally Posted by chuyler1
Is there a tutorial on changes that need to be made to the intake for the hogged out Nikki?
I'm pretty sure Jeff has gone into it in detail in some threads on here. Search for threads he
has created and start reading. Note that other than channeling the rear part of the intake
and slight porting there to make the secondaries the same size, no other porting should be
done. Do not port match the intake ports to the engine ports, you will loose the lip that helps
reduce reversion waves coming back to the carb.
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Old Apr 18, 2017 | 11:57 AM
  #128  
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Ok got it, I think I did see a few posts on the channeling, wasn't sure if it was still recommended.
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Old Apr 18, 2017 | 01:28 PM
  #129  
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Originally Posted by t_g_farrell
I'm pretty sure Jeff has gone into it in detail in some threads on here. Search for threads he
has created and start reading. Note that other than channeling the rear part of the intake
and slight porting there to make the secondaries the same size, no other porting should be
done. Do not port match the intake ports to the engine ports, you will loose the lip that helps
reduce reversion waves coming back to the carb.
the runners on the primaries can be opened up a bit, RB manifolds have a spec size that I copied. Port "matching" is bad.
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Old Apr 18, 2017 | 02:04 PM
  #130  
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Oke lets get on topic again haha

I test drove only on primairies tonight and its a bit lean 13.2 13.5on WOT
Idle is 13.6 witch is nice
On partial throttle and cruising about 80km/hr its around 14, 14.5

I think i have to get an 118 jet for the primairy because the first jet i tried was an 120 and that was too big (about 11 at WOT) problem is to get the correct jet because my supplier doesn't has them listed.

Also checked the spark plug color and that seems good to me.
The darker one is the front rotor

(Edit) (found my other jets againðŸ˜)

Installed the 120 primaries and it got a tad richer (slightly colder outside)
13.5, 14 on cruise
12.2 to 13.3on WOT (depenting on RPM)
I have a 122 but think that will be too rich for sure maybe ill try it just too see what it does.

One thing that wonders me is that depending on accelerator position +/-75% it can get real lean but when i floor it it will get richer again.

I'm also curious what effect float hight and airbleeds have on mixture. I know one can affect the other but how much it matters.
Attached Thumbnails Racingbeat Holley or rotaryshack Weber or unknown 48 Ida-img_20170418_191635.jpg  

Last edited by klabatzie; Apr 18, 2017 at 03:23 PM.
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Old Apr 18, 2017 | 10:21 PM
  #131  
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70 air bleeds are the only size you will ever need.
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Old Apr 19, 2017 | 12:53 PM
  #132  
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From: Greenfield, Ohio
Originally Posted by klabatzie
Oke lets get on topic again haha

I test drove only on primairies tonight and its a bit lean 13.2 13.5on WOT
Idle is 13.6 witch is nice
On partial throttle and cruising about 80km/hr its around 14, 14.5

I think i have to get an 118 jet for the primairy because the first jet i tried was an 120 and that was too big (about 11 at WOT) problem is to get the correct jet because my supplier doesn't has them listed.

Also checked the spark plug color and that seems good to me.
The darker one is the front rotor

(Edit) (found my other jets againðŸ˜)

Installed the 120 primaries and it got a tad richer (slightly colder outside)
13.5, 14 on cruise
12.2 to 13.3on WOT (depenting on RPM)
I have a 122 but think that will be too rich for sure maybe ill try it just too see what it does.

One thing that wonders me is that depending on accelerator position +/-75% it can get real lean but when i floor it it will get richer again.

I'm also curious what effect float hight and airbleeds have on mixture. I know one can affect the other but how much it matters.
Sounds like it could be a little richer up top if you ask me.

12-12.5:1 around 5k rpm UP (wot) will net you some extra power, and smooth your torque curve.

those plugs should be a slight darker too. Your primary jetting isn't your bottle neck from the looks of it. If it cruises happily, and doesn't starve, the lean side saves gas. Harder to start, more cold blooded, and less torque part throttle though.

it's a 4bbl, so your focus on power should be emphasized on the secondaries. Go fat. With your upgraded ignition it'll fire even through AFR''s as low as 10:1 without breaking up (if it's direct fire), and you'd be surprised how little power you lose by being "too rich".

Give the engine what it wants. Looking at the plugs, it looks like it wants more to eat up top.

pm me and I can walk you through reading your plugs, and I highly recommend the use of GSLSE plugs to make it that much easier.
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Old Apr 19, 2017 | 02:09 PM
  #133  
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I wouldn't use 2nd gen plugs in a 1st gen, even with direct fire. I like BR8EQ-14
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Old Apr 19, 2017 | 02:17 PM
  #134  
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I've been using the rx8 plugs, kind of pricey but worth it to me. They seem to fire better than any other
plug and they will last a lot longer.
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Old Apr 19, 2017 | 02:40 PM
  #135  
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I'd like to try RX-8 plugs next.
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Old Apr 21, 2017 | 12:14 PM
  #136  
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From: Dalen, Netherlands
Originally Posted by t_g_farrell
I've been using the rx8 plugs, kind of pricey but worth it to me. They seem to fire better than any other
plug and they will last a lot longer.
NGK 6700 
{#3514, RE7CL} Laser Iridium
Leading; Gap 0.048"; Actual OE Part
These ones?

Originally Posted by Jeff20B
I wouldn't use 2nd gen plugs in a 1st gen, even with direct fire. I like BR8EQ-14
I had them in before the 2gen plugs i have the idea that it feels stronger now.
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Old Apr 21, 2017 | 02:01 PM
  #137  
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Yeah I think those are the ones. Don't remember the part number just got leading spark plugs for an rx8.
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Old May 17, 2017 | 12:50 PM
  #138  
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Didn't have much time lately but tried to find some info on porting the intake manifold.

I know portmaching the primary is not helping performance wise so I'll leave them alone

The secondairy only needs some cleaning up and than it will be good to go.

I changed the sparkplugs to the BR8EQ 14 but idle isn't smooth as with the second gen sparkplugs so I'll change them back. Will order the Rx8 plugs and see what those do

I think i've done the most i can do to an stockport so if this doesn't get more power then i have to leave it this way
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Old Apr 27, 2018 | 02:20 PM
  #139  
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Found out that the dyno I've tested on doesnt work properly so maybe i will go to an other one to confim the results.
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