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Discussion Starter #1
What is cam overlap and how do you adjust with a thundermax auto tune
 

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The bottom line is you are not providing the correct info for anyone to help you!!!! As far as I can see it the problem is with your build and you are searching for answers. Your cam is what lift??? Your compression ratio is WHAT??? DO you have a correct base map?? The cam over lap has nothing to do with your problem the T-Max with the correct base map will auto tune your bike. You must have a mechanical problem somewhere or the incorrect base map. Did you have the intake leak??. If your cam is not a high compression cam the the bike won't run right and if your engine is not a high compression engine the the cam may not be compatible. I have a SE259E cam and 10:5 to1 pistons and it has a .579 lift and it works well with the build this is a compatible cam with a wood 777 which has .575 lift. Any cam that has .570 lift or above is a high compression cam. If your cam is high compression cam and you are only doing 9: to 1 or 9:5 to 1 compression then you may want to look into a different combination.
 

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Discussion Starter #4
Duh look at my sig half the questions you asked are there

S&S Super Stock 79cc Heads Ported Polished Oversize Valves S&S Easy Start Cams 570 Lift 2 Into 1 Jackpot Headers Jackpot Power Tube Muffler Stage 1 Air Box
 

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So you reply back being a wiseass and still don't answer the questions, I see your sig has things done to your bike but we don't know if it's up to date or you left something out. You still didn't tell us the specs on that cam or do you want us to look it up? You also didn't state if you have stock pistons or something other? Please don't take your frustration out on a helpful member here, this isn't HDFORUMS.com. You have a prob, we're here to help, but rememeber give us all the info, most people here use a mobile app on thier phone which doesnt display all the info, or didn't you think of that? Please be curtious and kind, and I'm almost positive one of us on here will have an answer, diagnosis, or atleast point you in the right direction to get your bike running good again.
 

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I understand that Joe and I understand your frustration. Is the cam a .570 lift and there is no mention of the compression ratio. Did You put in High Compression pistons? OR did you just do the heads with over sized valves ?? JUST because you did the heads doesn't mean that you have a higher compression. IS your cam compatible with your build?? Just because builders tell you that things will work it doesn't mean it will work These SOB's will tell you anything to sell you a product. For example the SOB that did my stage IV had no clue and told me that I need to put a 58mm Throttle Body on and bigger injectors.

Then the SOB couldn't tune the bike on his dyno And I ended up getting a T-Max and it fixed most of my problems but I still had to tweak a few things and I also change out the 58mm TB and put the stock TB back on but to avoid changing the base map I still used the 5.3 grams per second injectors and the T-Max made all the adjustments needed.

The T-Max is a very good unit IMO and if it can't tune your bike then there may be other issues that may need to be addressed.

Did you check out the PDF on timing adjustment I posted on one of your threads
 

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Exactly, you have to imagine us all as idiots, we know nothing of your current build and I know it's cumbersom to keep typing all the same info again and again but we don't own your bike. Your builder may have no idea on to setup an engine package, or plain and simple something could be wrong as malfunction or just not the right part. Hell I've had the Dealership keep my bike for over 2 weeks for an engine stutter issue and they kept telling me it was my pipes, when I got it home I diagnosed it myself with a twisted to all hell fuel inj. wire that caused all my prob's!
 

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What is cam overlap and how do you adjust with a thundermax auto tune
Cam overlap is a mechanical design feature and is not adjustable by any means whatsoever after engine assembly is completed (with possible exceptions being extremely sophisticated pure race-only engines and dual overhead cams).

It is defined in degrees of crankshaft rotation while both the intake and the exhaust valves are being held open. The idea is to let the most recent outgoing exhaust pulse (a primary feature of "tuned exhaust" systems) help suck in the fresh incoming A/F mixture.

The amount of overlap is defined by the cam designer and is an element of the machining process - a fixed value, forever. It's a totally mechanical function and no ECM or "tuner" out there can change it.

Come on guys... already been said:

Cam overlap is when both valves (intake & Exhaust) are open. Cain't help you with the Thundermax.
 
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lift has nothing to do with compression requirments(duration and opening & closing specs determines what compression it should be set at),the .570 likes to be set @ 9.8-1 (10.0 max),second overlap is what it is and cant be "adjusted" with your T-MAX.a S&S .570 is a mild cam and not really seeing why your haveing a problem tuning it.we use ALOT of them and are tuned with no problems
 

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lift has nothing to do with compression requirments(duration and opening & closing specs determines what compression it should be set at),the .570 likes to be set @ 9.8-1 (10.0 max),second overlap is what it is and cant be "adjusted" with your T-MAX.a S&S .570 is a mild cam and not really seeing why your haveing a problem tuning it.we use ALOT of them and are tuned with no problems
Excellent info prodrag and completely concur. Thanks for filling in the gaps I left open.

ETA: I honestly have no clue about the T-Max though. I would assume that, being billed as "automated", then ignition control is an included feature and self-adjusted on-the-fly somehow. Anyone know for sure?
 

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Discussion Starter #11
thanks

Thanks for all the help SORRY ABOUT BEING A SMARTASS
 

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Thanks for all the help SORRY ABOUT BEING A SMARTASS
I wouldn't sweat it too much myself. We're all willing to learn something new (or should be anyway) and us ol'pharts are expected to be cranky sometimes (aren't we? I sure hope so.). Therefore, you're not alone.
 

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Thanks for all the help SORRY ABOUT BEING A SMARTASS
I think your reply was warranted. All you did was ask a simple question.

I'm curious, why did you ask? Are you trying to solve a problem or learn something?

Why single out overlap, it's only one factor of many in cam design.
 

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Discussion Starter #14
Noise

Well I have a noise I dont know where it comes from I havw a stethascope and checked th heads,valve train, lower end,pushrods, allof the engine parts but when I got to the throttle bode without touching the sides of the metal it had a sound like a whop whop whop its not an italian sound lol I will be chan ging out the came to a short duration nex month
 

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whop whop whop isn't the best description I've heard but I suppose it could be sound of the breather venting or maybe throttle plate rattle. What air cleaner do you have? Does it do it only at idle? << just went back and saw 'stage1 a/c' in your sig...>> How do you have the heads vented?

570 is not a wild cam, going to a shorter duration cam would be a bad idea. I'd guess S&S would have made a cam suggestion based on their heads, what did they suggest? Who's advising you? What cam are you thinking of?

A properly running engine requires a combination of matched components. You've already raised compression with small combustion chambers, once you've made that change you really can't go back to short duration cams without serious ramifications. Decisions require careful thought once you've moved away from stock. Higher compression engines need more duration to avoid starting or serious pinging and knocking problems at higher RPM.

I personally do not believe based on what you're describing have an issue with cam or with the TMax. I'm not saying you don't have a problem, but I think you need to get another opinion than just your ear (not meant to be disrespectful, but each of us has a different definition of "normal").
 

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Discussion Starter #16
No Problrm

I have a stethascope I listened to the Heads.cams.lifters,pushrods,flywheels, all the engine but when I listened to the throttle body putting the stethascope insude without touching the sides I heard the sound whop whop whop is that cam overlap ??
 

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HOLY SHIT! These engines are not Swiss watches!!!! You are going to get valve train noise and the Butterfly valve in the throttle body is going to FLAP some causing some noise coming from the intake. You want to hear more noise from your intake put on a heavy breather you will hear all the noise you want then. You are nit picking your engine to much and if your T-Max tuner can't adjust to your build then there is something drastically wrong somewhere, and the problem may be in your build. Everyone has tried to help you so it is up to you to dig into the engine and find the problem. Good luck and fill us in when you get thing right.
 

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LOL. this is true what Mark said... it's never going to be quiet

whop whop whop sound is or isn't a real problem... could be your expectation needs adjusting.

The majority of people do NOT like the way Harleys sound apart from the exhuast note. Harley tries to keep mechanical noise in check for more reasons than the EPA. With the good you can get the bad. You can't just look on the internet and read how so and so installed x y and z thing and said WOW it makes a 150hp and believe it... That guy might ride 5 miles t the bar and back a couple times a month and that's it! No average pokey ass harley rider in the world will like the way that 150hp bike runs... other than for bragging rights. Have met more than a few guys who loved to brag about their hot rod motor and I rode with them and pass em out of pure disgust cuz they shift at 2k rpm and are getting passed by DWO's in shitty broke down cars.

My hot rod 95" sounded like it was crushing rocks and it was a bad ass running mofo.

Anyway... I'd say take it somewhere other than whoever has worked on the bike so far and ask for an opinion...
 

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I have a stethascope I listened to the Heads.cams.lifters,pushrods,flywheels, all the engine but when I listened to the throttle body putting the stethascope insude without touching the sides I heard the sound whop whop whop is that cam overlap ??
You want to hear cam overlap? Put your ear at the exit of your muffler. That is where you hear long duration and overlap.

What you hear in the TB is throttle plate rattle from reversion and that could very well be your whop whop whop sound... Pull the muffler or put a more restricive one on and run it and you'll know if its reversion.
 

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Thanks for all the help SORRY ABOUT BEING A SMARTASS
No biggie, just gotta treat everyone like we're dumbasses here, we don't know everything about your bike till you tell us, lol :D

Let us know how when you get her sorted and running good again!!!
 
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