BEST Hull, Modified Engine and Pipe???

[jaxracer]

Hi,

So the CMB is the same os MAC?

Can you find interior photos of the CMB and MAC to see the diferences.......

Best regards

David Dias

No they're pretty much completely diifferent animals, the timings are different, and if I remember correctly the bore and strokes are different. Like James I had similar experiences with the Mac as I ran one at one time. My experience with it showed that it's NOT for the novice boater. Across the powerband it was real finicky, either it ran as a missle, or it didn't run at all. This proved true with pulling the pipe out, mixture adjustments, etc, etc. Don't get me wrong, they are fast if you can find that sweet spot, but I never found it. About the best and only one that I've seen run consistantly was Joe Kneseck's on a purple Lynx in Atlanta.

On the otherhand the CMB's pto used to be a big issue back in the day when they stacked the bearings and the housing used to wear out and it would start sucking air. Since the more recent motors have come out(late greenhead version, and in the current RS), I haven't had any issues nor heard of anyone with issues, and thus far (knock on wood), no broken cranks.

But all that said, I'm gonna stick with my 1st suggestion, take the villain with the OS and go out and have FUN, learn a few things, and then worry about going fast.

~Mitch

 

[topfuel443]

Define "a lot of work". And where do these mythical "bolt on and go" engines come from? I f you don't take the time to check the internals for cleanliness, and proper assembly and clearances you could very likely end up with a bolt on and slow...or worse, bolt on and blow.

Read the post above yours from me. Thats the 'lot of work' I mentioned. Checking a new engine for cleanliness is not exactly what I would call working on them to get them to operate properly or on par with another engine. When you have to make a new head button, open up the case, change timing on the sleeve, relieve tolerances, etc., that's a lot of work.

You want a bolt on engine? Nothing mythical about it. Buy an OS. Pull the headshim, throw 60% nitro in it, set it up and bolt it on. Its that simple. My sport boat runs about 1-2 mph slower than my Nova powered Mod boat. Look what Kentley just did with the OS at the TT's in NC. He doesnt have a super "special" engine, its just a regular old OS, with a WHOLE lot of set-up and prop experience = 60+ mph.

As another note, OS is about the only manufacturer I would trust running right out of the box.

~James

 

[topfuel443]

Mike... Nice try! LOL...

~James

 

[LarryConrad]

Define "a lot of work". And where do these mythical "bolt on and go" engines come from? I f you don't take the time to check the internals for cleanliness, and proper assembly and clearances you could very likely end up with a bolt on and slow...or worse, bolt on and blow.

Read the post above yours from me. Thats the 'lot of work' I mentioned. Checking a new engine for cleanliness is not exactly what I would call working on them to get them to operate properly or on par with another engine. When you have to make a new head button, open up the case, change timing on the sleeve, relieve tolerances, etc., that's a lot of work.

You want a bolt on engine? Nothing mythical about it. Buy an OS. Pull the headshim, throw 60% nitro in it, set it up and bolt it on. Its that simple. My sport boat runs about 1-2 mph slower than my Nova powered Mod boat. Look what Kentley just did with the OS at the TT's in NC. He doesnt have a super "special" engine, its just a regular old OS, with a WHOLE lot of set-up and prop experience = 75+ mph.

As another note, OS is about the only manufacturer I would trust running right out of the box.

~James

James,

Maybe I just got lucky with my Macs. Mine have the head clearance set to .006" the water restricted, and the carbs reworked. I have never seen one run well with the stock carb, and I can't get mine to run consistently without a third channel needle. After three seasons of racing I have finally have one bolted on a boat I can keep on the water for 6 laps.

 

[HTV Boats]

Lots of great advice here but the answer to what is the best is there is not a clear answer. Assuming your asking whats the best heat race setup and not straightaway. There are many powerhead and pipe combinations that will run high 50's an into the 60 mph range. Yet there is not a consistent tunnel boat that will finish at those speeds. Look at the first 3 place results at major races the last few years Namba Nationals, Internats and the best race the Charleston World Tunnels. There you will find the best posibilities. HTB,Vision,Lee Craft, Lynx and Sniper will be on the list.

As in Nascar no clear cut winner at any track. The best setup and strategy that day wins. Consider you have a 350 Camero, will just putting a 1000 cfm carb make it the king of the street? The balance between carb,compression,headers,intake manifold and cam are more important than just a big carb. Boat setups are a balance of HP and reliability that compliment handling and driving style or capabilities. HP beyond a hulls capabilities even in the best hands can be a disaster to race. The motor pipe and PROP need to work together and fit your racing needs. Do you want acceleration or top end? Will you give up a couple mph for handling?

As has been said the OS will be very reliable and maybe as fast as many hulls will handle. I have owned and raced Rossi, Nova Rossi, CMB's, K&B's and now only have OS's powering my fleet. The Nova and the CMB had power that was the best. The CMB was the toughest to get consistency out of. Tired of DNF's went to OS and actually winning more heats and races with an OS. You can get a chrome sleeve cut to pipe timming and with a tune pipe still have reliability. Kris Flynn has them on this board. Will not be as fast as a Nova or CMB but may surprise you how close it comes. Irwin, silver bullet or cooper pipes seem to be as good as any. Get in the game have fun and you will learn as you go. Rather than tie yourself to an exotic expensive motor that rarely runs consistently start out with an OS. It has the best lower unit and you can always spend the big bucks later.

Mic

 

[Tim_Duggan]

I've played with them all. For all out brute horsepower Novarossi was best for me. For all out speed - The lynx hull was the fastest for me. That combination was very, very hard to race with here in Australia, but if it could finish a race it would usually lap the field.

 

[TUNLBOTR]

There are many powerhead and pipe combinations that will run high 50's an into the 60 mph range. Yet there is not a consistent tunnel boat that will finish at those speeds.

Mic

HUH ? Beg to disagree, O shiny headed one. You must have been asleep in the hauler at the Tunnel Champs. NOVA (RB CONCEPTS) LYNX did just fine, rough water, smooth water. Led 29.75 of 30 laps in modified, found a lap boat when he turned around on me, head on.

David,

Consistent Tunnels require consistent drivers. You race the water to the boats ability.

It's not just the best boat or motor.

RP

 

[ozbryan]

Hi,

I think tha MAC .21OB us the same of the CMB .21 OB

Isn´t it?

Best regards

David Dias

Not exactly. The MAC OB is more similar to the MAC buggy engine. Its just doesnt work great without a lot of work, and then it is very finicky. Every now and then one will perform well, but its not just a "bolt on and go" motor.

~James

James im interested in your comment here.. i run Mac obs and have no problems with them at all.. I run a stock one and so dose James Kessing in our club and they are two very competetive boats..

Can i ask what you mean by alot of work??

The CMB ob has issues in the PTO.. it breaks cranks... I personally wouldnt go a new CMB.. if you want CMB get a green head LS much better motor. Or win the lotto and buy a Nova LOL

We have also broken three CMB RS's, crank and two rods for no real reason. Not real high in my preference of engines, but at the same respect there are a couple guys who played with them enough to get them going good and be reliable.

The MAC, like I said, they have issues all on their own, crank case volume, bowl volume, etc. It's been a while since I have messed with one. All I know is 90% of them that I have seen and run have been pigs until you do some work to them. Once you are able to get some RPM, they get finicky with getting on the pipe. There is a reason not many of them run around here, its because the Nova is king. He was asking what we thought were the BEST engine, so thats what I mentioned. It sounds like you guys have had good luck with them for whatever reason, that's great! Don't get me wrong, I don't want to discourage any one from a particular brand, just giving my perception of the engines based on my experience. If my opinion sways someone one way or another, so be it. I can honestly think of 3 MAC OB's (out of probably 15 or 20) that I have seen over the years that have been competitive, not really the gamble I want to take. The rest were consistently slow or randomly fast. Hardly ever consistently fast. In fact, my race partner has one in his trailer that is probably one of the fastest boats I have ever seen, but its only that way 1 out of 4 heats. Its not for lack of trying with it either, its just a headache.

~James

Thats cool man, was just interested in what you thought needed working on is all... I found the stock carb is crap.. I put a 20J on from the OS ob and it ran great straight away and an irwin pipe helps it go to.. it may not be a Nova but its quick..

Like you I say the OS is the best you can buy for your buck.. David dont think when it comes to OBs

the more HP you can throw at it is best.. you need to finnish to win with these lil suckers! haha

 

[HOOTERS Racing]

i love my cmb ls motors iv never had an issue with them and just ask oz mine are quick i wont change to an rs ill just keep buyin up all the

ls stuff i can its handy havin a spare motor or two lol and as for the pto i use mac ptos in mine or i get new ones made the same as a mac pto

cheers

 

[HTV Boats]

There are many powerhead and pipe combinations that will run high 50's an into the 60 mph range. Yet there is not a consistent tunnel boat that will finish at those speeds.

Mic

HUH ? Beg to disagree, O shiny headed one. You must have been asleep in the hauler at the Tunnel Champs. NOVA (RB CONCEPTS) LYNX did just fine, rough water, smooth water. Led 29.75 of 30 laps in modified, found a lap boat when he turned around on me, head on.

David,

Consistent Tunnels require consistent drivers. You race the water to the boats ability.

It's not just the best boat or motor.

RP

I think we may disagree on the definition of reliable or bulletproof. At the Worlds RP was "The Man". Drove a perfect race with what may be the fastest or surely in the top 5 fastest 21 tunnels I have ever seen race. Now Randy also only used the speed needed to win every heat. So was it the boat or the foxy veteran on the transmitter? A lot of both. I have seen a few Lynx not finish comming from behind at local races where the other 3 of the top 5 are. I just feel there is not a 21 tunnel that runs over 55 mph that can ride the pins for 6 laps, locked throttle, in traffic on a consistent basis. Meaning 80% of the time. Maybe why I have gone to a less than 55 mph setup with an OS. Never going to blow you away but may outpoint a few and win some races. I think in racing HP generally is generally ahead of boat design or capability.

Mic

 

[bob miller]

maybe a shaman with a very stong running 21 ob could handle greater speeds and rough water ? just a thought...bob miller

 

[Grimracer]

Good fun here..

Now that I have read all this and been involved i would like to go back and just address the question again.

Boat - Nemesis

Motor - CMB Green head

Pipe - Silver Bullet (long)

Having said this..

Lynx

Nova Rossi

Cooper

Would be my second choice.

Thats my take.

Grim

 

[Tim_Duggan]

maybe a shaman with a very stong running 21 ob could handle greater speeds and rough water ? just a thought...bob miller

Tried that too with an NR - much better heat racing proposition in our race water here than the Lynx was with the same engine. Sacrificed speed for consistency, so to speak.

 

[David Dias]

David,

You are new to this, so the overload of information you are requesting as a new boat enthausiast is a bit much. Many a boater jumps in and gets money invested in happiness, only to receive misery in the end. That is a recipe for selling, not enjoying this hobby.

Your first boat should be one you can go to the lake and have fun with, learn how to drive, and learn fine points like setup, prop selection, getting something you feel comfortable with.

Be able to join a club, and run with other boaters. There isn't a person on here that won't help you, but you are far away, and people you can run with will help your experience.

Hopefully there are races that you can attend, and that will be your most beneficial as a boater, other boaters running the same size boats, and you can learn a lot of the fine points of Tunnel boats.

Much of what we do ends up being defined by Dollar$, how fast do you want to go. Speed costs money. Fun is free, keep fun in it first, get settled in, then start to climb the money ladder. You will take steps up, and take steps back as you go into the modified engines.

Starting out your best bet right now is the OS XM 21 outboard. Reliable, parts are readily available, and run really good. I am running a 5 year old OS that gets bearings once a year, and still hauls butt.

You can upgrade this to a modified and will run well with minimum work, or you can buy a out of the box modified (CMB) and start the money game.

Run for a year enjoying the first one, keeping headaches low and fun high.

Start building the other one, and don't rush the build, you have a fun boat that will help you make decisions on the other.

And you have another persons opinion. Put a OS on your boat, start enjoying, filter through all of this and keep asking questions. The advice on here is great, but YOU are the one that has to enjoy it in order to stay in it.

I started over 20 years ago with a stock boat, got involved in a local club, and learned to have fun with other tunnel racers. I have watched many people jump in, spend unreal amounts of money trying to go "fast like him", and a year later you could buy all the stuff for 50 cents on the dollar......Fun first David.

Stay in touch.

Randy Premo

Hi,

Randy I´m not a begnner, I had run with another Hulls and the FSR 3,5cc and 15cc

When I post, was to find the best hull, engine and drive, because on the tunnel class I don´t have the same experience on the FSR, if you want some help on the FSR class I´m open to help you........

Best Regards

David Dias

 

[Mike Luszcz]

Nemesis or Lynx...Shouldn't it be the Best AVAILABLE hull! lol...In that case, the Vision 20????

 

[Grimracer]

He did not qualify that........ h34r: :lol:

 

[Mike Luszcz]

He did not qualify that........ h34r: :lol:

Grim, You could always re-release the Nemesis!!!! I would love the #1 spot on that list! Mike

 

[David Dias]

Hi,

I like the both hulls

Best Regards

David Dias

 

[TUNLBOTR]

David,

My post was not to offend you, if I did I apologize. From the question asked, What is best boat/ motor and you being NEW to IW led me to say what I did. Yes I would like to know more about the ABC's of FSR in the USA and where our FSR organization is here, so that would be great to hear about.

So I will answer the question as directly as I can then.

Best Boat / Motor / Pipe combo?

Boat - LYNX - Pull the record books for IMPBA and NAMBA and look up.

Flawless performance and handling, quality and workmanship, how many do you want to buy?

Motor - Nova Rossi is awesome, Crankshafts and PTO units available on IW through VansRacing. Carl Van Houten builds the parts that win races. Be ready to spend a small fortune to catch what we run now.

Pipe - Many different pipes available, Lynn Cooper (Cooper Pipes) made a killer pipe, but is hard to find, but is the Fastest PERIOD.

Randy

 

[Mike Luszcz]

Heard the Shawns Vision 20 won some of the heats this weekend down in florida against some lynx's and other hulls!