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XLIII
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Discussion Starter · #1 ·
Well, here's an interesting one. I've got the V&H Dresser Duals on my '05 FLHTCUI. 95", 10:1 SE Perf Heads, 37G w/ 2 degree advance.
W/ V&H Basic slip ons, it had 90 ft/lb Tq and 86 HP.
Went to Samson Rolled Thunder mufflers w/ the same setup, retuned to the same 13.5 AFR as we were running w/ the other muffs and lost 9 HP.
Fooled w/ timing to no avail.
One good old wrench I know asked around and some folks thought over scavenging w/ the Samsons and the duals. Any other thoughts?
Don't have the sheet scanned, but no low-end dips, pretty flat torque curve fron below 2k that starts to decline between 3.5 and 4k, and the HP flatlines at 4.5k.
 

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The loss of 9 hp refers to a base line test you did the same day/same tuner?
It sounds very strange to me that the bike run out of steam above 4500, something is restricting flow IMHO. You are sure that the cam is the cam you believe it is?
 

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XLIII
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Discussion Starter · #4 ·
Not same day, but same tuner. And the only thing that was changed was the mufflers and exh gaskets, from SE to the ones that come w/ Rineharts. Tq actually increased by 2 ft/lb.
Somebody said the cam # is stamped on the inside end. Fat lot of good that does.
 

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I know you're still looking for those lost 10hp and torque...those unequal length duals make the tuning a real bitch ..especially the rear cly. The Samsons in my opinion have too little back pressure and too little volume(not sound). Tried them on a 95" 204 cammed Road king with the stock header and we lost the bottom.
If it were mine..at this point I would run the stock header with a set of slipons with 1 3/4" baffles..and tune for 13.5 AF with as much timing as it will take before the power falls off ( knock retard turned off on the SERT). Turn the Knock sensor back on and tweek if needed.
I bet the torque will peak slightly higher...but will surley hit sooner.
The horsepower flatening at 4500 is a real mystery....cause the heads will certainly flow for a climb to 6000 ...they did on my dyna with a tw8g.
Eventually ...that cam has to be checked...just to be sure it is as advertized.
Only other thought...a local builder named Mike Peplin of "mikes Customs" had on two ocasions ...cam gears from Andrews that were miss marked...one bike had lots on compression and bent the valves trying to start....the other ran like ****.
I know you checked the timing marks..but if the marks are wrong on one of the gears it sure would explain a lot.
 

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killer sperm
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Dave have you done a compression test? The gearheads on this forum could tell you what to expect for CCP. It seems to me that if the compression is higher than expected you may have gotten a milder set of cams than you ordered. Or maybe different pressures between cylinders could suggest mismarked gears? Hell I dunno, I'm still lookin' over my shoulder for that gd chupacabra.
 

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XLIII
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Discussion Starter · #7 ·
SYCLONE said:
I know you're still looking for those lost 10hp and torque...those unequal length duals make the tuning a real bitch ..especially the rear cly. The Samsons in my opinion have too little back pressure and too little volume(not sound). Tried them on a 95" 204 cammed Road king with the stock header and we lost the bottom.
If it were mine..at this point I would run the stock header with a set of slipons with 1 3/4" baffles..and tune for 13.5 AF with as much timing as it will take before the power falls off ( knock retard turned off on the SERT). Turn the Knock sensor back on and tweek if needed.
I bet the torque will peak slightly higher...but will surley hit sooner.
The horsepower flatening at 4500 is a real mystery....cause the heads will certainly flow for a climb to 6000 ...they did on my dyna with a tw8g.
Eventually ...that cam has to be checked...just to be sure it is as advertized.
Only other thought...a local builder named Mike Peplin of "mikes Customs" had on two ocasions ...cam gears from Andrews that were miss marked...one bike had lots on compression and bent the valves trying to start....the other ran like ****.
I know you checked the timing marks..but if the marks are wrong on one of the gears it sure would explain a lot.
With mine the bottom is great, it's just the top that sucks. I've got torque from 1800 RPM on up in spades, until it falls off early.
 

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MegaGlide said:
With mine the bottom is great, it's just the top that sucks. I've got torque from 1800 RPM on up in spades, until it falls off early.
Sounds like a set of 26g's....but with 10.0:1 I would think you'd of had a heck of a time tuning out the "pings" were that the case.
 

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XLIII
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Discussion Starter · #10 ·
Ok, I spent some time this morning going over my dyno charts and thought I'd throw out some more info and see if it means anything to anybody smarter than me, which is most of you...

With the Basic slip-ons, 4th gear was 86HP/90Tq, 5th gear was 83Hp/88Tq. Lower numbers in 5th.

With the Samson Rolled Thunders I got 77HP/91Tq in 4th, but in 5th the numbers are higher, 80HP/95Tq.

I'm so confused.:dunno:
 

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MegaGlide said:
Ok, I spent some time this morning going over my dyno charts and thought I'd throw out some more info and see if it means anything to anybody smarter than me, which is most of you...

With the Basic slip-ons, 4th gear was 86HP/90Tq, 5th gear was 83Hp/88Tq. Lower numbers in 5th.

With the Samson Rolled Thunders I got 77HP/91Tq in 4th, but in 5th the numbers are higher, 80HP/95Tq.

I'm so confused.:dunno:
More HP in 5th gear is the rule as parasitic losses in the direct gear are lower, your second set of runs makes sense. Found a simialr difference in my previous built.

Are you sure that the numbers for your first run are in correct order? Other than a change in the bike set up on the Dyno (tire slip, etc.) I can't find a reason why it shows lower ## in 5th
 

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MegaGlide said:
I haven't ever had ping one.
I'm friggin' baffled.
Some extreme settings of timing and AFR in the ping prone areas can iron out almost all pinging at the expense of power. I do not know the SERT options as to change only section of the timing curve (creating a dip in a ping prone area).
You should be able to check the timing of the cam by using a 'timing disc' (wording?). Open the cam chest, install the timing disk , watch the movement of the pushrod and check duration, intake opening/closing and have at least n idea whether the cam is close to what you believ it is....
This would drive me nuts too, I would have torn apart everything long tme ago, but that's just my impatient me.........
 

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XLIII
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Discussion Starter · #14 ·
No pinging had to be tuned out. Never was any the whole time he was tuning, and no knock retard on my data runs.
 

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Beg..borrow another set of cam gears. Check the outer gears for correct timing marks (dots in relation to keyways or flat on the pinion) if ok..pull the plate to check the inners.
 

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killer sperm
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SYCLONE said:
Beg..borrow another set of cam gears. Check the outer gears for correct timing marks (dots in relation to keyways or flat on the pinion) if ok..pull the plate to check the inners.
We've been tryin' to get MegaGlide to tear into his motor for some time, but that boy's stubborn...
 

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And..runnin true duals .. he cant use the "exhaust is a B*tch " to remove excuse. Hell ..can check the outers in a half hour.
 

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Just to throw a dyno tuners input into the mix. I talked to the ECM tuner for Zippers at Daytona last weekend and I asked about pipes. I said I wanted torque and never really went above 5,000rpm.
He said that they had found a very torquey combination of the Bassani duals and Samson Rolled Thunder pipes. Bottom end would be great, because of the restriction. Yet on the other hand, that same restriction causes the motor to fall off on the dyno at high rpm. Specifically he said about 48-5,200.
Sounds exactly what you are describing.
 
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