Top's 5 port update

[Jerry Wyss]

Guys, I've just had a chance to measure the timing numbers...I am very happy! For some reason I thought it was going to be really consertive, but instead it is just about perfect for an out of the box motor.
Exhaust - 180.6*

Transfers - 126.5*

Blowdown - 27.1*

Crank opens - 215.9 ATDC

Crank closes - 55.45 ATDC

Total duration - 200*

Glenn

Ok, I wanted to ask the question but didn't before. Does anyone consider that 200* crank duration to be a bit low

with the sleeve timings listed?

I generally go for atleast 210* crank timing in my 21 to 30 O/Bs with sleeve timings in that area,, is this 200* crank timing

considered normal for this size I/B engines?

JW

 

[opio]

You guys are talking marshin to me, lol, is there any resources that could teach me about the timing and all that yall are talking about? I know how to do some stuff but i don't know what im doing when i do it lol

 

[Jerry Wyss]

You guys are talking marshin to me, lol, is there any resources that could teach me about the timing and all that yall are talking about? I know how to do some stuff but i don't know what im doing when i do it lol

I'm a minor leager in this area compared to some on here. I learned using the trial & error method and picking

up some tips from various engine modders that are members here.

RCBoat.com has some tech papers on several things that are a big help. You first have to learn how to measure the

timings you have before you can go anywhere.

Gordon Jennings Two Stroke Tuners Handbook is a good read and will provide you with some basic formulas.

It's mostly an "act" of doing rather than "asking" sort of a deal.

JW

 

[opio]

sounds good thanks for the info, your right about the "act" part i just wanted something to gimmie a heads up on where to start lol thnaks again

 

[Jerry Wyss]

sounds good thanks for the info, your right about the "act" part i just wanted something to gimmie a heads up on where to start lol thnaks again

I asked one question from Jim Irwin many years ago about a cetain engine and it sent me into years of development

of that engine. That engine had really inexpensive parts so I could afford to make a few mistakes. That scenario just

doesn't exist nowdays so that kind of experimentation could be expensive.

It is a fun part of the hobby if your passionate in that area,, you can always have strong running engines and your able

to help others get a smile on their faces.

Measuring the timings you have is a must, then where to go from there, and "how" comes next.

JW

 

[steve wood]

exhaust is also low for what we run, but thats easily taken care of

 

[moparbarn]

You guys are talking marshin to me, lol, is there any resources that could teach me about the timing and all that yall are talking about? I know how to do some stuff but i don't know what im doing when i do it lol

there are some good threads right here on iw. search timing, intake timing or ex. timing. some were started as stand alone threads, just talking about intake or ex. not timing in general . hope it helps!

 

[Glenn Quarles]

Yes, you guys are right...these numbers are a little on the low side, but NOT TO BAD! It makes for a very nice running engine right out of the box that will pull a good prop, have good power and still RPM about as much as you would want. And it is perfect for guys that like to mod their engines because it gives them a little space to play with, but doesn't take a lot of work to make it run with anything out there.

Oh, and have I mentioned it is only $215?!?! Yeah I guess I have....

Glenn

 

[Jerry Wyss]

Yes, you guys are right...these numbers are a little on the low side, but NOT TO BAD! It makes for a very nice running engine right out of the box that will pull a good prop, have good power and still RPM about as much as you would want. And it is perfect for guys that like to mod their engines because it gives them a little space to play with, but doesn't take a lot of work to make it run with anything out there.
Oh, and have I mentioned it is only $215?!?! Yeah I guess I have....

Glenn

now thats what I call a whippin' ,, ya ok steve? :lol:

 

[steve wood]

like i said, easily taken care of

 

[LarryConrad]

I think Santa is bringing me one for the Blackbird he is bringing me.

Wow Larry you better trade in that car of yours for a mini van to hull all them boats.

 

[Glenn Quarles]

Yes, you guys are right...these numbers are a little on the low side, but NOT TO BAD! It makes for a very nice running engine right out of the box that will pull a good prop, have good power and still RPM about as much as you would want. And it is perfect for guys that like to mod their engines because it gives them a little space to play with, but doesn't take a lot of work to make it run with anything out there.
Oh, and have I mentioned it is only $215?!?! Yeah I guess I have....

Glenn

now thats what I call a whippin' ,, ya ok steve? :lol:

Sorry, no whippin' intended...I have great respect for you guys that have commented on the technical aspects of the motor.

Glenn

 

[Jerry Wyss]

Yes, you guys are right...these numbers are a little on the low side, but NOT TO BAD! It makes for a very nice running engine right out of the box that will pull a good prop, have good power and still RPM about as much as you would want. And it is perfect for guys that like to mod their engines because it gives them a little space to play with, but doesn't take a lot of work to make it run with anything out there.
Oh, and have I mentioned it is only $215?!?! Yeah I guess I have....

Glenn

Yes you did, and thats a very good price too, all your prices are very reasonable. I also like how you pointed out

the diff between the Top, Rex and Nova models. I've been here "a while" and have never heard that info being stated,

it certainly clears the fog of NR's endless engine models.

J-Dub

 

[Preston_Hall]

Granted, Kentley is one of the best when it comes to extracting the most out of a 20 hydro, but the mere fact that he has taken a $200 motor and with the same mods as a much more expensive one gotten basically the same performance speaks volumes. We need more affordable top performing nitro motors just like this example that KP has put on the table and I think that is really the point he was trying to make.

What makes Kentley different from many others was that he has listened carefuly, always gave me feedback how changes affected performance. Sometimes engines went few times back and forth to get things right. Many guys thought he was getting some special engines from me but that is not the case just regular heat racing engines. It was easy to make angines to work for him as he did not try to impress me with BS, I knew he was using very good boat, prop, pipe and will follow my recommendations as far as engine break in and setup goes. He also made sure I know if engine was crap. I have modded over 400 Novarossi engines and I bet I haven't heard back from more than 5 people how engine is running.

It is great for boating that this engine runs well.

Frank, you crack me up. A heat race motor? You must be joking! I have seen those motors go 100mph. Everybody knows a heat race motor cannot go 100mph in a rigger. Nor can they go 75mph on an outboard.

But folks, THEY REALLY DO!

 

[K-ZAM]

What makes Kentley different from many others was that he has listened carefuly, always gave me feedback how changes affected performance. Sometimes engines went few times back and forth to get things right. Many guys thought he was getting some special engines from me but that is not the case just regular heat racing engines. It was easy to make angines to work for him as he did not try to impress me with BS, I knew he was using very good boat, prop, pipe and will follow my recommendations as far as engine break in and setup goes. He also made sure I know if engine was crap. I have modded over 400 Novarossi engines and I bet I haven't heard back from more than 5 people how engine is running.It is great for boating that this engine runs well.

Hey Frank I ran the engine again last Thursday and it ran 79 MPH in my Hummingbird. I expected it to go 80+. I will be sending it back to you for warranty work so dont be sending me a bill just yet.

 

[F.Orlic]

What makes Kentley different from many others was that he has listened carefuly, always gave me feedback how changes affected performance. Sometimes engines went few times back and forth to get things right. Many guys thought he was getting some special engines from me but that is not the case just regular heat racing engines. It was easy to make angines to work for him as he did not try to impress me with BS, I knew he was using very good boat, prop, pipe and will follow my recommendations as far as engine break in and setup goes. He also made sure I know if engine was crap. I have modded over 400 Novarossi engines and I bet I haven't heard back from more than 5 people how engine is running.It is great for boating that this engine runs well.

Hey Frank I ran the engine again last Thursday and it ran 79 MPH in my Hummingbird. I expected it to go 80+. I will be sending it back to you for warranty work so dont be sending me a bill just yet.

Too late Kentley, bill is on the way to Preston Hall as per your instructions.