Kentetsu

For those of you who don't live close enough to actually ride in my car, here's a ride in my car (listen to the amount of throttle work taking place):

http://www.youtube.com/watch?v=aqTrHIN--2Y

Aside from the initial take off at the start, there were only 1 or 2 places where I could really open it up due to the heavy rainfall. Most of the race was run on primaries only, and I will honestly say that the mechanical secondaries on the carb is what won that race for me.

Actually having complete control of that (rather than having some vacuum solenoid kick into them and surprise me), let me push a lot closer to the edge while still maintaining traction. You can easily feel when your "up against" the secondaries through the gas pedal due to the added spring tension.

Most of what you are actually hearing is not exhaust noise by the way. Most of it is coming from the intake due to the RB air filter cover. But you can hear when I'm just "dipping into" the secondaries a little bit, and of course you can hear it when I go wide open.

Anyway, not to sound like a comercial or something but, Sterling does really great work and deserves the credit. I'll vouch for him.

Kentetsu

From what I understand (and I may be mistaken, since I have no 1st hand experience with them), they are great at high rpm wide open throttle. However, being a two barrel, they are not as responsive under other conditions (part throttle, cruising, etc.).

Are they better than a Sterling at wide open/high rpm throttle? I doubt it. Again, from what I understand, the Sterling flows at least as much air as the engine is capable of needing. And the benefits of a four barrel should be obvious (better partial throttle performance, smooth cruising, mpg, etc.).

Please feel free to beat on me if I am wrong in any way.

OneRotor

iTrader: (3)

will do. Will there be any auto-x's between March 9 and March 15? That's when Spring Break is for me. If not, i'll be back down for a few days before summer classes start.

Scott1982

Nice,
I am impressed with both your driving and the smoothness of that engine. I also have never heard the overrev buzzer before ! Your idle seems nice and low.
Scott

Kentetsu

Whitey: I don't know yet if there will be races during that timespan, but I will try to let you know when I find out. Otherwise, if you are ever going to be in the area let me know and if nothing else we can get together for a cold one.

Scott: Thanks for the kind words. She ran pretty well for having well over 200k miles on her. I always said that I've never lost a race due to a lack of horsepower.

usnaudi

iTrader: (2)

kentetsu,

I will shortly join you in the Sterling club, and will definitely try and provide accurate feedback concerning the performance gains of a Sterling. I have also experienced a 12a SP with a Holley 600 and RB intake. I can't wait to feel the difference between the two set ups.

Super82

iTrader: (1)

What type exhaust is that Kent?

BUMBLEBEE7

iTrader: (1)

No experience with Sterling. Holleys are very easy to tune. I had a 600 on SP it was the best and I had 650DP on BP work flawlessly. I never had problem tuning a Holley carb. I heard of people's bad experiences with Holley that's about it.

vipernicus42

iTrader: (4)

usnaudi keep an eye on the DATE on the posts in threads that you search up.

You brought this thread back from almost a year ago...

Personally I've had 2 Sterlings (one of the VERY early models that was zinc plated and "only" flowed something like 425cfm, and one of his standard 465cfm, powdercoated Sterlings) and I've put Sterlings on 2 other FBs and I have to say they're amazing.

I put my car on a dyno with it, and despite the fact that my motor has 220,000+ km on it and pulls compression numbers that are borderline rebuild (6.9kg/cm2 all around) I still made more horsepower at the rear wheels than the stock car had at the flywheel!

Honestly, I wouldn't personally go for anything else. These carbs were *made* for our cars. I can't say enough about a carb that had a 600rpm idle and plenty of power on tap straight out of the box, before I even put it on the dyno. It's smooth and powerful and I'd recommend one to anybody driving an FB.

Jon

Super82

iTrader: (1)

I'm going to jump in here. Now I personally don't have any experience with either, although I do have a Holley 465 kit that I haven't installed, and I have a homemodded Nikki.

The Holley comes with a much better intake manifold. The runners are much longer and tubular, and also have a smoother angle. The Holley is much bigger all around, as well. I haven't gotten exact measurements but it appears all four barrels on the holley are bigger than the secondaries of the Nikki. This could be better or worse, depending on how you interpret it. The Holley is also MUCH easier to work with, tune and modify. This isn't my opinion, it is the opinion of many racers for over 100 years. The Holleys are performance made for easy tunability and racing. The Holley is less of a mess of tubes and more of a bare bones racebred carb. The Holley 4160 is a timeless, tried and true design with limitless capabilities.

I'm not knocking either, but I must say you've got to keep in mine where you are hearing alot of the praise for Sterlings. Most I hear either comes from Sterling himself or from people who haven't used Holley's. Everyone who has ever used a Holley has said it has completely changed the motor from mild to wild. I also have to question where Sterling gets these flow ratings. I know that the Holley 465cfm has the capacity to flow much, much more, so maybe the stock 313cfm (is that right?) Nikki can, but I find it hard to believe that that much can flow thru those TINY primaries and not so big secondaries. I don't know if Sterling has actually done flow test but I find it a little convenient that it is exactly 465, exactly the same as his biggest competitor. I also find it odd that Racing beat claims that you will have major problems even using the Holley 465 without headers while Sterling doesn't.

The Holley is for pistons and Sterling is for Rotary comments are dumb, IMO. Racing beat is the formost in rotary performance and they chose to use the Holley. They tuned and prepped the holley for the rotary engine. I really doubt racing beat would bother using a holley if it wasn't the best for the engine, and I know they made many changes to it that make it possible to work. The RB Holley 465 is designed to work with our engines, and it is not just an inferior V8 carb. Whats better-A tuned racing carb or a tuned economy carb? And that is basically what the Nikki amounts to, one of the major points in its design is economy and emissions.

Just my $0.02, I'm sure the sterling carb is indeed a good product. The numbers and happy users don't lie, but I felt there wasn't enough of the other side of the coin in this thread.

RotaryMelon

iTrader: (7)

I know a guy who his selling his RB holley 465 setup and upgrading to a sterling as we speak

trochoid

iTrader: (6)

Super82, you have a lot to learn in regards to the Sterling/Holley carb debate and Racing Beat. One reason RB sells the Holleys is because the Dellorto DHLAs, Weber DCOEs and Mikuni 44PHHs are no longer made. Those were the bread and butter wrap around carbs in their day and the best suited street carb. While the Weber IDAs are still produced, they are still mainly a race carb and lack a choke/starter circuit.

The Holleys are a poor substitute. particularly for autocross and road racing. As an all out drag carb carb, they work fine.

If you doubt the capabilities of Sterling's carbs, read through Paul Yaw's website. Sterling picked up where Paul left off. While I've never run a Sterling or Yaw carb, I have had Holleys and imho, they are not the carb for a rotary. My personal preference is Rotary Engineering's dual Weber DCDs, which are also out of production. The DCDs are still being made but the rotary intake manifolds aren't.

Siraniko

iTrader: (13)

PM Japan2LA as his buddies at European Motor works in Hawthorne CA has one in their shelf. I saw it last Saturday while I was picking up IDA parts. If Im not mistaken, it is brand spanking new.

Kentetsu

Super82: your comments regarding ease of tuning may be applicable to a stock Nikki carb, but not a Sterling. Sterling replaces many of the parts with Holley parts so that changes can be easily made. And don't get Sterling started on flow testing, let's just say that he has done his homework...

Kentetsu

Racing Beat (stock port version). If I had it to do again, I would have gotten the street port version... But overall I've been pretty happy with what I've got.

usnaudi

iTrader: (2)

Viper,

I had no Idea that we weren't allowed to bring back an old thread. But what's done is done, so the right thing to do would of been to start a new thread with the same question? IMO usually people will just paste a link to an old thread to answer your question. So why not go to the root.. If there are different procedures that need to be followed as far as gaining information regarding a specific subject that was already discussed. I would like to know please. I don't want to look like a jack ***.

Super82

iTrader: (1)

Why would the DHLAs, DCOEs and 44s be better? Now I'm not doubting your knowledge, you've been in rotary much longer than me, but I personally have ridden in a car with a weber and it wasn't for me. I surely wouldn't say they are 'better', I would say they are different. You are comparing apples and oranges, a two barrel v. four barrel.

Now I don't know exactly why RB started the Holley kit, but I do know they have been making it for a long time. I read some sort of old racing beat literature and they were making the holley kit and it was like late 80's or so. When were those two barrels stopped in production?

Fair enough, I didn't know that. What I know is that I've worked and tuned with my nikki and it has been a complete bitch all the way thru. And at the flow testing I don't want to start a huge debate, so I'll leave it at that. I just find it a bit odd.

RX-7 Chris

iTrader: (19)

I'm running the RB SP Holley setup with a large SP 12A and it is running great. I had to do quite a bit of tuning to get it running like it is now. I had to put it on the dyno and mess with quite a bit. My problem is I'm at almost 7000 feet so any car setup for sea level need to be worked on.

I had to change out the AP cam and vets, and quite a bit of adjusting. After doing all that it runs great and pulls hard at all rpms.

My next step is a better exhaust setup. Right now I have a stock port RB exaust setup. I will be installing a 2.5" exaust with a magna flow muffler.

OneRotor

iTrader: (3)

The answer to this question is a double edge sword. For some topics, it is a pain in the *** for someone to bring back the thread or post a new thread, because it's like beating a dead horse. For other threads, like this one, it is completely reasonable to just bring this thread back from the dead, as there were not many posts and not all questions have been answered, IMO.

usnaudi

iTrader: (2)

Fair enough 85mtu, So now that we have that out of the way.

Sterling VS Holley 465CFM

Pros and cons is basically what I would like to hear about, obviously some pros and cons have already been touched on by Kenetsu and Trocho. But if there is more information available I wouldn't mind reading it. And yes I have visited both sites multiple times Sterling's and Yaw's.

trochoid

iTrader: (6)

Mel,

I'm quite suprised there are any new RE DCD intake manis left. Since you're the resident Weber guru, you should pick it up The 28-/32 mm DCDs are still availible new. I don't really need another one since I have both the 12A and 13B setups. If need be, I can give you recommendations for venturi and jet sizes.


One of the big problems with the Holley is the intake. The Nikki has a small passageway cut betwen the primary runners under the carb base to deal with overlap and help balance the idle. The Holley intake is opened up under the carb base, exposing all 4 runners, all the time. The net effect of that is turning what we all think is a 4 barrel into a 2 barrel with 4 butterflys. The RB Holley intake for their bigger carbs has this opening machined even larger to a depth of 1", creating a plenum of it's own. This causes even more overlap and the engine won't idle under 1400 rpm for anything but a streetport.

I suspect there were many reasons RB added the Holley to thier line of carbs. Back then everyone and his brother could tune a Holley. It was THE choice of aftermarket carb. I installed them on both my Road Runner and Ranchero with great results. They were cheap and parts were everywhere. Mikunis, Webers, Solexes and SU carbs on the other hand came on British, Italian and Japanese cars. That fact alone made tuning those carbs a 'voodoo art' and very few mechanics even knew where to start.

The neat thing about the RE setup is it's a true 4-barrel carb. Each runner has it's own totally seperate butterfly. As a result, I can drive the 12A 1/2sp-1/2bp on the widebody like a streetport when running on the primaries and can the idl as low as 800 rpm. Once the secondaries open feeding 1/2 bridge secondaies, all hell breaks loose. Another benefit is one can change the venturi, which effectively changes the size of the carb, i.e., going from a 44 mm to 52 mm carb.

orion84gsl

iTrader: (5)

I can't remember where I posted what I'm about to type, nor can I gaurantee that it will get the same point across, but I will try anyway.

The stock Nikki was designed by Mazda, the company that brought the Rotary to the masses, and still does, decades later. They designed it for both fuel economy and power on the 12A engine. As we all know, it's hard to get both, especially back in the late 70's early 80's. The Holley, RB tuned or not, was designed by Holley, to huff air into a V-8. Period. RB made it work because they didn't want to screw with the Nikki, and as Troichoid stated, back then everyone and their mother could tune a Holley.

What Super82 clearly hasn't done is any research on the Sterling. The first thing you have to do is take any thoughts in your head that this is the stock Nikki, and beat your head into a wall until they are gone. The only thing that qualifies the Sterling as a Nikki is that it uses the stock body and still bolts to the stock manifold. This carb is not a Nikki, it is a Sterling.

In laymens, Dennis took a carb designed by the OEM rotary god to operate well on the engine they perfected, and improved it where needed for performance. Out of the box it is a massive improvement over stock. Simplified linkage, minimal parts sticking off of it like the stocker, and it is easily tuneable, you just unbolt the top of the carb and unscrew the jets from there. Seems easy to me.

I would like to know why it's impossible to fathom that someone that loves the rotary would go through the trouble of flow testing a stock carb, then using his skills gained from other lines of work, reshape the venturi's of the stock carb to flow as much as his biggest competitor (RB Holley).

In short, no I have not driven a Holley powered rotary. Given the chance I will, gladly. I am not knocking the RB since it clearly works and those that have it are happy with it. I will however defend the Sterling. I absolutly love mine, and I appreciate the work Dennis has put into it, and the service he has given. I think his customer service is second only to RE-Speed, and they are very well known for that. I believe it truly is the best choice, simply because of what it is.

Ask yourself, do you want a carb that was designed for one engine, then modified to operate on a completely different engine, or do you want one that was designed for your engine, then properly modified to give that engine a swift kick in the ***?

Siraniko

iTrader: (13)

thanks for the offer bro. I appreciate it. I dont mind trying it out but I have 2 more sets of IDA carb/intake and I'm going FI. One of the RX-3's will get a haltech, BBK TB, and T70 while the other will get the S4 TII set-up with stock ECU and such. But again, Wacky's mind may change on a daily basis like the stock market.

Sterling

Well I sure can't let this go...
What modifications have you done to the Nikki? Have you turned the venturis? What's the diameter? What inlet/outlet angles are you using? Have you flowed it?Absolutely. Sadly, the stock manifold is a bottle neck at this point. I'm making fixing that my goal for '09."How you interpret it"? That's pretty vague. Please explain a few ways that could be interpreted. (You should familiarize yourself with the Bernoulli Principal, and how a venturi works first.)Just which model Holley has been around for "over 100 years"? It's funny, because last I knew, the Nikki carb I modify has only been around for around for about 35 years.You sure seem like you are. Not only do you seem to be knocking the Sterling Nikki, but as you continue, you begin to knock me personally, which is precisely why I wasn't about to let this post go without a little "straightening out of the facts".While I do agree that it's difficult to sort because very few have actually had the luxury of trying both, the praise you read about regarding either is mostly because the stock carburetor is extremely restrictive, that's all. It's very simple. Take a muffled system, put a better intake & exhaust on it, and now it's fantastic.
The person doesn't really know if it's optimum because they only had the stock setup to compare it to. I always ask for feedback from anyone who might be switching from a Holley, because I'm genuinely interested to hear what they have to say. Unfortunately I don't have such feedback. I will certainly document it when I get it. In the mean time, I do my best to explain why the modded Nikki will outperform the RB Holley, as a carburetor. I always acknowledge the stock manifold as being terrible as compared to the RB Holley manni.
This really rubbed me wrong. There's never anything wrong with challenging someone on their claims or product, but you REALLY should've done your homework on this first.
Rx7Carl did the flow testing. He and I spent two years doing all the R&D. He flowed DOZENS of different venturi cut configurations for me, as well as airhorns, modded airhorns, manifolds, and several modded Nikkis where I slimmed T-shafts, boosters, and OMP lines individually to find the flow impediment values.
If you're doubting his cred, you're gonna be pretty damned unpopular around here.
Regarding "tiny" venturis, you need some "Air Flow Dynamics 101" and you need to look up how a venturi actually works. Bigger is not better for low RPM. But I'm not going to bother educating you on this. Look it up.
Regarding the flow rate, Carl & I were quite happy with our first model 3-4 years ago that flowed 420cfm. But young, naive kids would insist that the Sterling wasn't even worth a try because the RB Holley outflowed it. We knew better, and we knew that even if we made the carb flow more, it still was going to be bottle necked by the manni. But we went ahead and reconfigured the venturis so it would breathe 465, just for them. It took a LOT of flow testing to get the venturis just the right angle to produce that flow and not sacrifice signal to the primary main.
Regarding the header exhaust, if someone doesn't know they need a header exhaust with a performance carburetor on a rotary, they have no business buying performance parts for their rotary. I can also say here that you've never even bothered to read my website where I not only explain the additional requirements for the Sterling Nikki, but also exactly what modifications I make to the Nikki.You are being very foolish in your comments here. The Holley IS in fact a piston engine carb. The Hitachi/Nikki was designed specifically for the rotary engine, and further more, it is a fairly performance oriented carburetor that has been crippled by US emissions over the years. However, likening the STOCK Nikki to a STERLING Nikki is absolutely ludicrous. You simply haven't done your homework.It's fine if you want to have equal representation of both products in a "Brand X vs Brand Z" thread, but you must use FACTS to support your assertions. You've made a lot of them, using no facts at all.
Now, I've explained on this forum several times why a 4 bbl carb with smaller primaries is better than one with large primaries that flows just as much. It's a fact, and in order to understand it, you must educate yourself on how a carburetor works; particularly with regards to the venturi and the emulsion system. Once you know how these things work together, it becomes obvious how overcarburetion causes crappy low end performance. Period.
I've also presented the math necessary to prove what size carburetor is actually needed for the 12a & 13b. It's very easy, and there's simply no arguing with math.

I'm not a carburetor "guru". Jeff20B probably knows as much if not more than me about the Hitachi and Nikki carbs. Carl certainly does. But I do know about the venturi and how it works. I'll toot my own horn, and even ***** my product, and respond to folks like you, for this one simple reason;
-I stand behind my claims and my work, and I offer a 30 day money back guaranty of satisfaction. I give my customers all the after-sales tech support they ever need. I make these things by hand, and I don't make much money on them. It's certainly not a "thriving" business, and only pays for my shop (which is simply a garage), my tools, and my rx7 habit. That's it. But it's a passion, and it's grassroots. I wouldn't waste my time making these carbs if fellow rotorheads were unhappy with my work.

I'm not pushing my product, I'm pushing the truth.

RX-7 Chris

iTrader: (19)

I wish we had someone with the dynos to prove which is better. I really don't think that it would change much though because people will not believe unless they saw in person.

In my opinion, I think they are both great carbs. They just both need to be setup properly to work great. The RB mani is far superior to the stock mani, I think we all agree on that. I'd like to see what you come up with to change this sterling.

Since I have the RB SP Holley setup and I've turn the carb completely apart. I few things I found out. The RB Holley is a stock carb out of 312ci Ford with some added linkage. RB says they do custom work in the inside, this is a complete lie. I called them to ask what the jets were and they said they custom drilled them. For anyone who knows about carbs, you know that you can buy any size you need. I got the specs on the stock carb and compared with the RB carb and they all match, even the jets.

OK so now I sound like I hate the Holley setup but I don't. The reason I went with the Holley setup is because I have 3 other cars with holleys. This makes it nice to have 4 cars with holleys because I only need one set of tuning stuff. I put my car on the dyno and I was able to do some jet, and AP cam and jet changes. With the time I spent on the carb I was able to get great A/F throughout the rpm and no flat spots. The car runs great. I friend of mine has a SP 13B with a dual Webber setup and my car is not as fast but it starts even when it is -5 in the morning.

As for the venturi sizes and spread bore vs. square bore. This is an argument that has been going on for at least 40 years. The advantage to a spread bore is you have a little better gas mileage if you stay out of the 4s. But a properly tuned square bore will not be much worse. It all comes out to matching air and fuel right. At 7000feet where I am, we need all the air we can get. Talking with old carb guys up here, they all say that they like to go a little bigger in cfm and match the jets with A/F. I will admit the choke on the Holley really restricts the flow. I wish I could remove is but since it is my DD I can't. Carbs like demons really improve all this.

The one thing I don't agree about this whole argument is piston vs. rotary carb thing. Yes the Holley was designed for a piston engine and the Nikki was designed for a rotary. The thing is both motors have basically the same combustion cycle. Both carb work the same, they just look different. They have all the same parts with just a few small changes. I Nikki is basically a small Q-jet carb.