Best non-Nikki set-up?
12-06-10, 10:33 AM
#26
carb whisperer
12-06-10, 09:20 PM
#28
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I am the guy who started the thread that got sterling nicknamed "the carb napper". He's been paid and I've been waiting since Sept. 15, 2009. Coming up on 15 months. I don't know if this is typical but it's my story. I'd recommend looking elsewhere.
12-06-10, 09:31 PM
#29
carb whisperer
What of the possibility of it being lost through the mail? Ive had some important things "lost" en route before. Somehow bills never disappear though.....
12-06-10, 09:44 PM
#30
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No, I sent a money order and besides sterling, when he answers at all, has never disputed that he was paid. I'm just really tired of hearing"it will get done later this week or next week". I still do believe that I'll get a carb someday but I was originally waiting on this one to mahe the car run. I have since bought a junkyard carb and rebuilt it. I've gotten it running but with my being carb challenged, I've had a mostly non running car for well over a year.
12-07-10, 08:36 AM
#34
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why wait for sterling? i stopped by one of the other mikes shop, and he's been running modded nikki's for probably 30 years.
12-07-10, 11:13 AM
#35
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I actually have been. The carb I rebuilt didn't work at all at first. It now (about 3 times into it) works good except for hot starts and at idle. I'm getting more comfortable with it and it's getting better every time. To the OP; sorry for getting off topic, I was just trying to warn you about how the sterling might go for you. I still hope I get one.
12-08-10, 03:34 AM
#36
No one has suggested the carb I am using - a 13b carb, used on the RX-4, Cosmo and Rotary Pickup. There are two styles, 1974-75 and 1976-78, slightly different fuel inlet arrangement, but both seem to work about the same for me. I have one in a 1984 GSL with a ported 12a, and one on a 4-port 13b, both give good power for normal street driving, and have no significant cold or hot driving issues. The only weak point is the accelerator pump, which should be replaced before you start driving unless the carb comes directly off a good running car.
My 12a dyno tested at 130hp to the wheels with mild porting and a RB header. The 13b has mild porting (secondary ports only) and a stock cast iron manifold, and I estimate it has about 160- 165 hp at the flywheel.
My 12a dyno tested at 130hp to the wheels with mild porting and a RB header. The 13b has mild porting (secondary ports only) and a stock cast iron manifold, and I estimate it has about 160- 165 hp at the flywheel.
12-08-10, 08:24 AM
#37
Waffles - hmmm good
iTrader: (1)
with the Dell puts down 134 rwhp (this is on a dynojet). I would expect
your ported 12A to be around 150 something.
12-08-10, 11:55 AM
#38
carb whisperer
But, the rotary carb stuff is cool because you can put stock snorkels on them and stuff. Fuel curve is probably spot on, too.
12-08-10, 09:54 PM
#39
Out of all your options,(being holley, weber, and nikki) I'm not sure what i'd go with. All have there strengths. Holley being popular, weber being a race bred; Insanely simple, precise, well fuel atomizing carburetor, and super easy to tune if i may add(with endless possibilities)...
With the nikki on the other hand, it's just about the right size. It's 'original' so you know it's not far off. And, in my opinion. Once the nikki is stripped and rebuilt it's good to go on just about anything. It CAN make big HP numbers. Racing Beat states that a modded Nikki can make 240 HP SAE on a Normal Bridge 12A, not a J-Bridge. Normal bridge.. So, i think the nikki is very sufficient. No telling how much more torque the nikki made than the Weber or Holley with those numbers.
I'm not going to say what is better than what. I have a weber, but, i'm going back to Nikki.
That's my preference/opinion.
With the nikki on the other hand, it's just about the right size. It's 'original' so you know it's not far off. And, in my opinion. Once the nikki is stripped and rebuilt it's good to go on just about anything. It CAN make big HP numbers. Racing Beat states that a modded Nikki can make 240 HP SAE on a Normal Bridge 12A, not a J-Bridge. Normal bridge.. So, i think the nikki is very sufficient. No telling how much more torque the nikki made than the Weber or Holley with those numbers.
I'm not going to say what is better than what. I have a weber, but, i'm going back to Nikki.
That's my preference/opinion.
12-09-10, 10:49 PM
#40
"I think you need more carb on that ported 12A. My stock port 12A
with the Dell puts down 134 rwhp (this is on a dynojet). I would expect
your ported 12A to be around 150 something. "
I think the Dellorto has much more potential than an RX-4 carb. According to the experts at RB, the stock 12a carb is rated at 315 cfm, the RX-4 carb at 345 cfm, only a small gain. In addition, I should point out that I only port the secondary intakes on my motors, using the RB street port template.
I collected a few of the RX-4 carbs back when everyone was throwing away those cars, might be harder to find now. I also made my own intake manifold, starting with an RX-3 manifold and adding a flange to fit the bigger carb. In other words, it was all free to me except for my labor. All of the other options discussed here will make more power, but they cost money - I went for the cheap alternative. I have been driving it like this since 1997, and I am happy with the overall performance and driveability. It has noticeably better performance than a stock 12a car and gets the same fuel mileage.
with the Dell puts down 134 rwhp (this is on a dynojet). I would expect
your ported 12A to be around 150 something. "
I think the Dellorto has much more potential than an RX-4 carb. According to the experts at RB, the stock 12a carb is rated at 315 cfm, the RX-4 carb at 345 cfm, only a small gain. In addition, I should point out that I only port the secondary intakes on my motors, using the RB street port template.
I collected a few of the RX-4 carbs back when everyone was throwing away those cars, might be harder to find now. I also made my own intake manifold, starting with an RX-3 manifold and adding a flange to fit the bigger carb. In other words, it was all free to me except for my labor. All of the other options discussed here will make more power, but they cost money - I went for the cheap alternative. I have been driving it like this since 1997, and I am happy with the overall performance and driveability. It has noticeably better performance than a stock 12a car and gets the same fuel mileage.
12-10-10, 12:40 AM
#43
carb whisperer
Dude. Holleys do not infinitely tune. You are severely restricted to the emulsion tuning based on the carb the metering plates came with. You can even go to billet blocks with exchangeable bleeds, and youll be hard pressed to get it "right".
I even used a 390 hp with billet blocks and an "infinitely tunable" fuel curve, and it sucked *** on my 12A. The 12A barely notices even radical changes in the holley emulsion well.
Example: My 390 hp had 3 circuit emulsions, and every orifice in the well of each block was .28
Theoretically, changing any of those to a larger orifice would lean out that part of the RPM band. (the top orifice in the well is the lower RPM, middle is mid range, while bottom is high RPM)
My car was very rich everywhere but the bottom end, so I increased size on the bottom orifice to .35 I was shocked to learn that that large of a change only lowered my AFR up top by an average of 0.1 AFR!!! I went back and changed to an even larger size (.42) and tried again for a final average of 0.3 difference in AFR from the tiny .28
At that point, the well was opened up too much to go any further. Went back to .28 bleeds and changed the primary high speed air bleed from a .29 to a .35, only to get freaking detonations in the mid range. Because the carbs are so small for use with a 12A, the emulsions tuning is a super fine tuning effect. (Holleys at least)
Secondly, holley transition circuits suck *****. The transition fuel supply is reliant on the acc. pump and power valve which are largely a catch-up game. The other suppliers of transition enrichment are the Idle air bleed, idle feed restriction and main jet. Changing the main jet screws with everything else, and going to a larger idle feed restriction for transition sucks for the idle quality.
You also have to realize that the throttle blade angle also affects transition a great deal, so with the proper angle, you cant tune the idle speed without screwing up the transition circuit. My carb idled at over 1200 rpm set to the correct transition slot/blade angle. Any lower, and hesitation.
Of course all of that can be fixed with ***-tons of plug fouling fuel thrown at it. I did this eventually and had to deal with craptastic 11 mpg. Plus it backfired a lot too.
And then you have the the biggest flaw in the design, the stupid fuel bowls. Cornering sucks ***** (high g-load AND moderate load) And mine typically sucked on Decel too.
With the crap fuel economy, high idle, and even crappier reliability, I threw my arms in the air and bought the carb that was designed for the rotary in the first place, the Nikki.
Horsepower is only bragging rights if your car runs ok while making it. Youll be the laughing stock of your neighborhood pulling over after ever stop light to play with the idle screws on your holley, throwing fireballs and just generally running like crap unless your on an even surface going in a straight line. Holleys suck period, even worse on rotarys. People like them because they are modular and lightweight. They can even be reliable on conventional engines, but only just.
Say NO to the holley....
I even used a 390 hp with billet blocks and an "infinitely tunable" fuel curve, and it sucked *** on my 12A. The 12A barely notices even radical changes in the holley emulsion well.
Example: My 390 hp had 3 circuit emulsions, and every orifice in the well of each block was .28
Theoretically, changing any of those to a larger orifice would lean out that part of the RPM band. (the top orifice in the well is the lower RPM, middle is mid range, while bottom is high RPM)
My car was very rich everywhere but the bottom end, so I increased size on the bottom orifice to .35 I was shocked to learn that that large of a change only lowered my AFR up top by an average of 0.1 AFR!!! I went back and changed to an even larger size (.42) and tried again for a final average of 0.3 difference in AFR from the tiny .28
At that point, the well was opened up too much to go any further. Went back to .28 bleeds and changed the primary high speed air bleed from a .29 to a .35, only to get freaking detonations in the mid range. Because the carbs are so small for use with a 12A, the emulsions tuning is a super fine tuning effect. (Holleys at least)
Secondly, holley transition circuits suck *****. The transition fuel supply is reliant on the acc. pump and power valve which are largely a catch-up game. The other suppliers of transition enrichment are the Idle air bleed, idle feed restriction and main jet. Changing the main jet screws with everything else, and going to a larger idle feed restriction for transition sucks for the idle quality.
You also have to realize that the throttle blade angle also affects transition a great deal, so with the proper angle, you cant tune the idle speed without screwing up the transition circuit. My carb idled at over 1200 rpm set to the correct transition slot/blade angle. Any lower, and hesitation.
Of course all of that can be fixed with ***-tons of plug fouling fuel thrown at it. I did this eventually and had to deal with craptastic 11 mpg. Plus it backfired a lot too.
And then you have the the biggest flaw in the design, the stupid fuel bowls. Cornering sucks ***** (high g-load AND moderate load) And mine typically sucked on Decel too.
With the crap fuel economy, high idle, and even crappier reliability, I threw my arms in the air and bought the carb that was designed for the rotary in the first place, the Nikki.
Horsepower is only bragging rights if your car runs ok while making it. Youll be the laughing stock of your neighborhood pulling over after ever stop light to play with the idle screws on your holley, throwing fireballs and just generally running like crap unless your on an even surface going in a straight line. Holleys suck period, even worse on rotarys. People like them because they are modular and lightweight. They can even be reliable on conventional engines, but only just.
Say NO to the holley....
12-10-10, 12:48 AM
#44
carb whisperer
12-10-10, 01:01 AM
#45
And Wacky, it takes me maybe 5 minutes to change any of the jet's/air bleeds on my Sterling. That's if the hood is closed and the engine is hot. If I'm in a hurry I can get it done pretty quick. The mods done to it allow for very easy removal of the carb top. Maybe it can be done faster with a 2 barrel, but we'd be talking a difference of a couple minutes. Not a huge deal.
If the only thing you can do is change jets/air bleeds, without trying out different size of venturies, then you're doing a half-*** job in tuning.
on a side note, if I ever decide to go back to Nikkis, it aint gonna be the nikkis out of FBs. It will be the real nikkis out of a RX-2/3. otherwise, I would rather push my car and take the bus
I;m sure I can still play with this one that I built 2 decades ago
my collection of carbs, old pix but you get the point.
12-10-10, 09:07 AM
#47
Waffles - hmmm good
iTrader: (1)
"I think you need more carb on that ported 12A. My stock port 12A
with the Dell puts down 134 rwhp (this is on a dynojet). I would expect
your ported 12A to be around 150 something. "
I think the Dellorto has much more potential than an RX-4 carb. According to the experts at RB, the stock 12a carb is rated at 315 cfm, the RX-4 carb at 345 cfm, only a small gain. In addition, I should point out that I only port the secondary intakes on my motors, using the RB street port template.
I collected a few of the RX-4 carbs back when everyone was throwing away those cars, might be harder to find now. I also made my own intake manifold, starting with an RX-3 manifold and adding a flange to fit the bigger carb. In other words, it was all free to me except for my labor. All of the other options discussed here will make more power, but they cost money - I went for the cheap alternative. I have been driving it like this since 1997, and I am happy with the overall performance and driveability. It has noticeably better performance than a stock 12a car and gets the same fuel mileage.
with the Dell puts down 134 rwhp (this is on a dynojet). I would expect
your ported 12A to be around 150 something. "
I think the Dellorto has much more potential than an RX-4 carb. According to the experts at RB, the stock 12a carb is rated at 315 cfm, the RX-4 carb at 345 cfm, only a small gain. In addition, I should point out that I only port the secondary intakes on my motors, using the RB street port template.
I collected a few of the RX-4 carbs back when everyone was throwing away those cars, might be harder to find now. I also made my own intake manifold, starting with an RX-3 manifold and adding a flange to fit the bigger carb. In other words, it was all free to me except for my labor. All of the other options discussed here will make more power, but they cost money - I went for the cheap alternative. I have been driving it like this since 1997, and I am happy with the overall performance and driveability. It has noticeably better performance than a stock 12a car and gets the same fuel mileage.
12-10-10, 09:20 AM
#48
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You also have to realize that the throttle blade angle also affects transition a great deal, so with the proper angle, you cant tune the idle speed without screwing up the transition circuit. My carb idled at over 1200 rpm set to the correct transition slot/blade angle. Any lower, and hesitation.
you can get the main circuit to come on when you need it, so its not really a problem, except that the idle mixture screws do less and the idle jet does more
12-10-10, 10:04 AM
#49
Say, you are married with 1 kid and have plans to have 2 or more kids. Would you buy a 2 bedroom condo unit? I say "NO" as you have to look ahead as a 2-bedroom will be too small for a growing family.
The above apply to cars as well. If I have to spend $300+ on a "modified" stock or a holley or 45 DCOE carb, I would rather spend a little bit more on an IDA (or similar) as I can re-use it shall I decide to upgrade to a ported motor; it just takes a simple re-jetting/change of venturies. However, if you are satisfied with running a stock 12-A and competes under a strick guidelines, then be it. And lastly, choose who you will line up at the light as you may get smoked.
Although I may sound like I'm preaching about IDA, that is not my intention. I just want to share my experience as you may end up having a collection of carbs just like me.
The above apply to cars as well. If I have to spend $300+ on a "modified" stock or a holley or 45 DCOE carb, I would rather spend a little bit more on an IDA (or similar) as I can re-use it shall I decide to upgrade to a ported motor; it just takes a simple re-jetting/change of venturies. However, if you are satisfied with running a stock 12-A and competes under a strick guidelines, then be it. And lastly, choose who you will line up at the light as you may get smoked.
Although I may sound like I'm preaching about IDA, that is not my intention. I just want to share my experience as you may end up having a collection of carbs just like me.
12-10-10, 01:07 PM
#50
carb whisperer
ALL carbs are like this. the IDA is actually a little too small for a big HP engine and will idle on the 1st transition hole.
you can get the main circuit to come on when you need it, so its not really a problem, except that the idle mixture screws do less and the idle jet does more
you can get the main circuit to come on when you need it, so its not really a problem, except that the idle mixture screws do less and the idle jet does more
I still cant stress enough the archaeic fuel bowl design. Youll hate it.
End rant.
P.S., I have still never run any sidedraft or downdraft weber, so I cant compare to those.