bad 83

iTrader: (3)

Dude! I have no beef with a Nikki. In fact, that is my weapon of choice on my 83 GSL blowthrough. I just know that the Holley will work. It's tricky trying to tune one that is too big for your application, but not impossible. If your engine is stock, I always recommend staying with Nikki, instead of the Holley. An average Joe can do the basic emmisions strip, rebuild, and manual secondarys on the Nikki, and be amazed at the performance. Like I've said in my first post in this thread, I'm not going to start an arguement, because I have ran both, and I know what both are capable of. Honestly, for the performance and the money, if I was you I would go with Sterling and call it a day.

Sterling

I'm just razzin' that's all.
Like I said, I'm not here to pimp. I had to set the record straight regarding the price though. The rest is all just fun.

84stock

iTrader: (5)

I have no doubt a sterling modified carb would work great on any 12a (ported or not). He has spent a lot of time on them. I am trying to advise what to do with what you've got.

ForsakenRX7

Ok, the 650 aint gonna work...ever. Now that I've gotten a better look at it I realize that part of the problem with the car is that the carb is just plain trash. Its rigged here and there. No good.
SO now the problem is I'm stuck with this damn holley manifold and fancy paperweight for a carburator. Sterling, if I understand correctly your carbs require both a stock manifold and a stock carb for the core right?
Anyone wanna buy a holley manifold? Seriously. I'm just gonna go back to the factory manifold and have sterling do the damn nikki up right. With the header and exhaust the lil car already has it should be cherry after that. Right?

84stock

iTrader: (5)

You can't go wrong with an Edelbrock thunder series carb on that intake! It's way easier to tune than a holley, and works very very well. Definitely the carb of choice for me. http://www.edelbrock.com/automotive_.../thunder.shtml get the 500 cfm model with manual or electric choke. Chaning primary jets is done with metering rods, simple! No fuel spill, just 2 screws and swap them out on the top of the carb. With the thunder series you dial in the secondaries with a screwdriver as well, no springs, no disassembly.

84stock

iTrader: (5)

pics

ForsakenRX7

I've just never heard much positive about edelbrocks. I constantly here the domestic guys complain about how they tend to cause a stumble going to WOT. I'm definatly gonna go with the sterling carb. He obviously knows his stuff and you can't beat the craftsman ship of an individual whose highly skilled at what they do.
Don't get me wrong, I'm not saying all edelbrocks stumble but just that is the biggest constant complaint I hear.

bad 83

iTrader: (3)

As with any carb, it comes down to tuning. If you are looking for a bolt and go without any tuning, then I suggest going with the Sterling. You will still have an air fuel mixture to play with, and your idle setting. As far as an aftermarket bolt and go, then the Edelbrock is better tuned out the box. If you need a stock intake, there are plenty of guys here in the forum that will hook you up with one fairly cheep.

Sterling

If you don't know what you're talking about, then don't.
A Sterling Nikki is modded to be more tunable than a Holley or an Edelbrock. I think that you seem to believe that all I do is hog out the venturis or something.
I've already said that since he has the manifold, he could certainly be happy with the money spent on an appropriate sized Holley (modded for the rotary, like the RB one). I'm not here to snag a sale. But when I see misinformation posted about the Sterling, I have to correct it.
Anyone can learn more by visiting my site or emailing me directly, and I can answer technical questions here, but I can't discuss price.

84stock

iTrader: (5)

Sterling, can I suggest you find a local camden owner and test one out on that application. I think on a 12a camden your carb would outperform the recommended holley hands down! The carb spacer that camden uses could likely be tapped for the nikki bolt pattern (or a new one made). I for one would really like to see the results! (I mean this in a positive way!)

Sterling

I intend to get the Camden.
I spoke with Dan Atkins @ Sevenstock and he showed Carl and I some very impressive dyno sheets. I can mill my own spacer if need be, but I don't think so. I think he'll tap it for me if I ask. If not, I can do it myself on the milling machine.
-Lots of other stuff to pay for first, though.

Jeff20B

iTrader: (13)

I have a 5" Camden for a 4 port 13B. Should I try a Nikki on it?

bad 83

iTrader: (3)

You know, this is why I hate trying to be nice and push some business toward somebody. I didn't fall of the tuning wagon yesterday. If I didn't know what I was talking about, then I wouldn't have chimed in any way. If you wanted to really help this guy out seeing as it is his thread (not a buy my carb because it's better thread), then you would have advised him how to tune the Holley he has instead of trying to sell him one. I think that is what the man asked right? I opoligize if me saying that your carb would be better offended you, because I thought you were trying to push one off on him. Geez, can't even pay someone a compliment anymore.

Sterling

My comment to you was regarding an inaccuracy about my carburetors. But since you opened up your knowledge of tuning for questioning, I'll tell you that you certainly give reason to doubt yours. Anyone who knows about carbs will tell you that trying to make a Holley 650 work on a 12A rotary is a fruitless effort. It's that simple. Anybody who says otherwise is either talking out their ***, or trying to resolve what the definition of "is" is.
Can you get it to run? Surrrre. But for a 12A rotary, you'll get more performance out of a stock Nikki with the secondaries wired up than out of a Holley 650.
While your tuning knowledge is questionable at best, I can certainly say with confidence that you obviously don't know jack about my carburetors (which was my point to you in my last comment) if you're telling someone that they should choose a Sterling Nikki if they are "looking for a bolt and go without any tuning", because that's simply not true. Tuning a Sterling Nikki can be a challenge because there are so many variables to work on. It's also part of what makes it better than any of the other 4bbl choices out there for the rotary.
The second "untruth" that you stated was about the Edelbrock in comparison to the Sterling, when you said "the Edelbrock is better tuned out the box" for the 12A, which is just plain... -well, I won't even say it.
The Edelbrock in question is a 500 cfm carburetor, again, too big to ever be optimal for a 12A rotary. So even that one is a poor choice.
To help the OP I've mentioned twice now that he might want to make use of that Holley manifold, which is a beautiful flowing manifold, and get a more appropriately sized Racing beat 465 Holley for it, even though for other reasons altogether, I find the Holley 465 to be less than optimal.
But at least he won't be trying to tune a Hemi sized carb to work on his 70 cid engine. Please don't make me out to be less than helpful to the OP simply because I needed to correct you in doing so.

Sterling

I dunno, Jeff. You should do something, though. All your "gonna-dos"... what's going on? Build something kick-*** and sell it! Slap that baby on a freshly built streetport , paint her the color "purdy", slap a Sterling on her and sell it. Then pay me back for the carb.
How much crap you got kicking around at yer place, Jeff? Seems yer always surrounded by parts.

bad 83

iTrader: (3)

..............

ForsakenRX7

Ok, at no point has anyone tried to sell me a carb. Hell read back and you can see that Sterling suggested that I buy the RB model since I already have the manifold. My complaint with that is the price.
People on this forum swear by the lil sterling nikki. That says a lot to me, means it works. Plus the fact its almost 200 dollars cheaper is the persuasion I needed to go that route.
If you read my post you'll see that I said the 650 is butchered anyway. Although from my general research (using the search on this forum)I found that the 650 is just way to much carb point blank. Yes it can made to work,but the car will never have its full potential. I'm the kinda person that if they have to dish out the money might as well do it right once.

Jeff20B

iTrader: (13)

I am surrounded by parts. It complicates the decision making process, but I manage.

The 4 port 13B has '74 spec intake ports and large exhaust ports. If the Nikki was modified to work on a plenum intake, would it work as well as an Edelbrock or Holley? Would a Sterling be large enough?

I have an Edlebrock 600 that worked well enough on a streetported 13B. It might be a little big for a '74 ported 13B. A Sterling might be just right.

How can I tell? Make an adaptor and drop a stock Nikki on it and see? What about the plenum vs seperate runner thing? Do the channels in the stock manifold and the small channels in the throttle body and carb spacer act like a mini plenum?

I once tried a 750 Edelbrock on the Camden and it acted like it was too big. It would bog if you mash the pedal. As I'd lift my foot the power would increase. That's the only exprerience I have with a carb that was obviously too big for the application. The 600 solved almost all the problems except it's still a V8 carb on a rotary. I'd prefer a rotary carb if possible.

Maybe there is a way I could test a Sterling on a Camden and inform you of the results?

Sterling

There's no reason to put a bigger carb on a supercharger. The flow rating of a carb is taken at atmospheric pressure. (14.7 psi). Add 5 or 10 psi of boost (or draw) through it, and the carb's cfm changes accordingly.
Obviously there's a limit to how small, as anything will eventually cause a bottle neck. But I don't think the Holley 465 or the Sterling will bootle up at less than 10 psi.

Jeff20B

iTrader: (13)

Hmm, since the air flow will increase through the carb when it's on an SC, would I need to increase or decrease the size of the air bleeds? How about fuel jets?

I would like to try a modded stock Nikki on my SC to see whether it is even a viable venture to run a Sterling on it. I'll keep you up to date on the progress. Please inform me which direction to 'tune' it with my selection of air bleeds and jets I have here; richer or leaner compared to an NA, and the reasoning behind it.

I only have the metric sizes, but it's a fairly decent selection. Air bleeds: 60, 70, 80, 90-primary, 120, 140-secondary. Fuel jets: 92, 93, 94, 95, 100, 105, 106, 117, 130, 140, 145, 150, 155, 160, 170

Edit: the carb currently has air bleeds: 70, 140 / fuel jets 100, 160

Sterling

You're asking me to tune a carb I've never seen on a motor I've never seen for an application I'm unfamiliar with. That's crazy.
You say you'll mod the carb, kind of nonchalantly, like it's no big deal, but I have no idea what you would do to it. And even if you told me, unless I played around with an EXACT duplicate, I could never just guess what jets to sink in it.
I know flow numbers and the science behind carb sizing, and I know jetting as it pertains to my carb. I don't have a supercharger to monkey around with, and until I do, I will have no idea what jetting to use. Even then, I would only know what jetting to use in a Sterling Nikki, because that's what I make, and they are all made identically.
As soon as you deviate the flow in any way from the norm, -in my case, my modded carb, then you change the whole dynamic of the way it needs to be tuned. If I changed the angle or the diameter of my venturis by even one degree or .5 mm, the tuning curve can be effected so much that one carb could need a eight or ten size difference in air bleed to achieve the same results as the other carb. That's why I can never answer these poor guys asking my help with their Yaw carbs, unless they've been done up for SCCA classes (because then I know that the venturis are stock). It's also why I don't go saying anything about Holley carb jetting. -I just don't know, never having spent the time dialing in a Holley.
The only way you're going to know is by doing it. But I will say this; If you're unsuccessful, just because you're modded carb doesn't yield good results in that application doesn't mean mine wouldn't.
If you can get your Nikki to flow 465 cfm and have no drop in signal to the main circuit @ 2K RPM, then you're golden. Anything from there that is too rich can be bled out, but if you have weak signal to the main down low, no amount of jet compensation can cure that.

Jeff20B

iTrader: (13)

Thanks for that.

Just so we're clear, I should describe what I've done with the carb and believe me when I say it was a big deal to mod it. I developed an appreciation for what you do.

Carb mods consist of mechanical secondaries, increased accel pump shot and duration, simplified choke. Venturi mods are out of my league.

Currently installed on a '74 spec ported 12A and performs really well, but this wasn't always the case. When I began tuning it, I started with 94 primary jets and 80 air bleeds. It was an improvement over a totally stock Nikki, but not by much. Only when the secondaries opened around 3500-3800 would it really pick up, running out of breath around 6500-7k. Next I tried some 100 primary jets and 70 air bleeds. The secondary transition is far smoother telling me the primaries are a lot more powerful. You can also feel the difference just on primaries alone. More enjoyable to drive. It also seems to have power up to at least 7k now and a little beyond.

That is where it sits at the moment. The engine is an '83-'85 12A with intake ports cut out to '74 spec, and the exhaust ports have been enlarged a little (2mm later closing edge and 2mm wider). It's a nice all around performer of an engine. I'm happy with it.

If I were to try this carb on a '74 spec 13B, I'm sure it would work pretty well, all things being equal. Of course since they aren't, that is why I'm asking for your advice. The intake ports are actually stock for '74 REPUs and they are what I copied when I ported the 12A. The exhaust ports had a set of previously ported upside down D ports, which had to be corrected. The end result is now a little bigger than T2 spec, closing about 5mm later. This was necessary to straighten out the closing edge. The opening edge is still stock.

Ok now that that's out of the way... this is the engine which is getting the 5" Camden. Last time the Camden ran, it was on a mild streetported 13B with an Edelbrock 600. The carb isn't perfect, but it seems to work until you try to hotrod it. Then things get problematic (goes too rich and stumbles around corners). Anyway the 600, while it does work on a streetport, may be too large for a '74 port. That is why I'm considering alternatives.

I like how my modded Nikki performs on the 12A. It outperforms every Hitachi I've ever tried on various 13Bs. It seems the Hitachis suffer from a fuel delivery curve problem at high RPM and no amount of fuel jet or air bleed juggling will solve it. That is the motivation behind the 6 port 13B Nikki project I'm working on for the GLC. It's also why I'm considering a Nikki on the Camden, if such a thing is possible. The Nikki is taller than a Hitachi or Edlebrock so hood clearance is an issue. I'll need to make a really short carb adaptor.

Now that you have a basic idea of how my Nikki performs with its current state of tune, as a general rule of thumb do I want to richen the fuel jets and use smaller air bleeds when going above 14.7? This is where I'm having trouble visualizing cause and effect.

Thanks.

Sterling

The stock Nikki flows 313 cfm, so that's your first problem. Even with the Camden, probably at anything over 5 psi you'll go lean at only 5K RPM.

If you want to use a Sterling on it, you might be able to drill and tap it for studs without a spacer.

84stock

iTrader: (5)

Put an edelbrock 500 thunder series and your camden and be done with it!

Jeff20B

iTrader: (13)

Sterling, it may be possible to tap the SC housing itself for Nikki studs if the width is compatible. They come with four threaded holes for a set of allen head screws which hold the Holley (squarebore) carb adaptor on. That is to say the 5" Camden does. I don't know about the 7".

Since you will most likely stick with a 12A, you will have to use a 7" SC because Atkins apparently does not offer a 12A manifold for the 5" and infact was considering phasing it out (they may have already). A big mistake in my opinion as the 5" is a little less parasitic. But I digest.

I have a brand new in the box Edlebrock 600. Anybody want to trade me for a 500? I might as well ask, right?