HarleyTechTalk

2007  FLTR 107" J&E Pistons, HPI  51mm, Woods 408G cams,S/E lifters, S&S pushrods, Woods 325 A/C, S/E rocker supports. S/E injectors,  SERT, (Head work by well known  porters.)

1. First dyno with Rhineheart Duals. 110.8 H.P. 118.3 torque. 500 miles later flywheels start separating. Tear down new crank  sent to Darkhorse pro plugged balanced with new H beam rods. (Peak power 5500 rpms)

2. Second trip to dyno 111.6 H.P. 115.4 torque was  told engine was being held back possibly exhaust. (Power not pulling above 5500 rpms.)

3.  Third trip to dyno with D&D fatcat with performance baffle. 109.3 H.P. 109.8 torque?? (Power Peaked 5500 rpms) :

I GIVE UP! What is wrong with this build? I've did everything advised.n this I could have bought a Jims complete cheaper than this project me .  These dyno tunes are all three done at different reputable tuners?





 

I think your last statement may have answered your question. 3 different tuners on 3 different dynos on 3 different days. How does it run?

Zach

One problem is your trying to compare three different dyno's. That's like comparing apples to oranges[imo]. You could get those different results using the same dyno on different days. What are your expectations ? Did you put this build together or did you pay someone else? Did you follow a proven recipe? Did you use the parts your head porter recommended? Just curious and I'm sure others will have plenty more questions.Check squish? Sumping? What did your tuners have to say?

All that said only 5.500 and flatline is a sign of breatning malladies, lack of fuel or improper timing, IMO. That cam in a 107" assuming no valve float should pull to 6,200 if none of the components are not limiting the breathing

First off replace the performance baffle in the fatcat with std or quiet.  That baffle with that cam is not good.

Second have you checked cold cranking compression?  If not do that.

Did the well known porter give you actual flow sheets for your heads?  What valve sizes, intake port size.

Doubt it is sumping much with those numbers but 5500 peak is not normal, again how well do the heads flow.  Can you post the dyno sheets w/afr curves?  

Heck,

It's got one of those crappy HD 6 speeds in it.. Different gear each run? Max
 

Quote from: Deweysheads on February 14, 2009, 07:11:10 PM
All that said only 5.500 and flatline is a sign of breatning malladies, lack of fuel or improper timing, IMO. That cam in a 107" assuming no valve float should pull to 6,200 if none of the components are not limiting the breathing

All parts were put together in a package except lifter and supports. These heads have heavy Bob Woods springs. The first tuner said he was surprised at the numbers knowing the porter work. Even they say it should be higher. The reason for different tuner was once again by advise. As for the cold cranking compression its 227 psi 8 pumps throttle wide open ffront and rear.  I'm at wits end.  

Quoteits 227 psi

That's kinda low...   

A little C4 will blow those numbers right off the scale ... or the dyno!

Without some hard data on the heads it's tough to say for sure what the problem may be.

Any diagnosis at this point is pure speculation and not even a good SWAG.

With the CCP figures you posted I'm wondering if it is simply a case of too much advance or the ECM is detecting detonation and pulling timing back. Did they try disabling knock sense when they were tuning? Did they even bother to check if it was going into anti-detonation mode? That'll kill power like crazy.

Quote from: fuzznut5197 on February 14, 2009, 07:31:15 PM

Quoteits 227 psi

That's kinda low...   

For what Bobby wants,,,  Max

QuoteFor what Bobby wants,,,  Teeth Max

Yeah.  He makes his cams intentionally noisy, so you won't hear the detonation. 

Vind, did you check it stone cold, or warmed up a little like your supposed to?

Friday the 13th is over ... full moon or has everyone been toking up?

Quote from: ederdelyi on February 14, 2009, 07:44:57 PM
Friday the 13th is over ... full moon or has everyone been toking up?

Maybe these peanuts I'm munching on are Sam & Ella'd   

Sorry when i stated 227 psi that was tested hot, not cold.    

227 is up there ... know the answer to my questions on knock sense/retard? I'd look there before tearing things apart or changing hard components.

Vind, go to this link and input your engine specs, the ccc results are reasonably accurate.

http://www.bigboyzcycles.com/TwinCamComp.htm

I don't know that answer,but i'll call monday and ask. The tuner did show me a chart and said the ECM was not pulling any timing out at or around 2000 rpms. He said if i was planning on any heavy roll ons to be above 2500 rpms. Is that what your wondering ??

Kinda sorta. Cylinder pressure increases with RPM. Knock activity needs to be monitored across the whole spectrum, not just low RPM. IF it's retarding at the top end it will kill power and is not uncommon with a build that follows the Wood recipe. Tha's why the Power commander has problems with builds like these, it lacks the timing flexibility to handle high compression builds. If the tuner only concentrated on fuel mapping and did not address the timing maps it is quite possible that could be a large part of the problem.

Why not post all three dyno sheets in the dyno section?  It may help some of the experts here pinpoint the problem.

B

Post the sheets with all the info, to include AFR.

i have my knock sensor turned off had to to get it tuned.
i think you might have to look for a more experienced tuner
G

"I GIVE UP! What is wrong with this build? "

Probably nothing but I'd agree with ejk if you lost power on the DnD the baffle is probably too big.. With the brand of gas you are getting, you might not make any more.. Also the HD 6 speed eats poewr.. Instead of worrying about the numbers, how does it run?? What about the quench?

Max

Quote from: fuzznut5197 on February 14, 2009, 08:01:08 PM
Vind, go to this link and input your engine specs, the ccc results are reasonably accurate.

http://www.bigboyzcycles.com/TwinCamComp.htm

"reasonably accurate" ?

Don't know where the poster lives, but the calculator shows 197psi@ sea level.

 

The spec sheet on those heads is one of the first places I would look, I mean do you have stage 1234 and CFM numbers. I have just done the heat cycles on my 107 and tomorrow I am taking it out to brake it in. It might be on the same why with the 6 speed. We will see in a couple of weeks, Depends on the weather