117 Dyno Results
- Thread starter K9husker
- Start date
stlmikie
I wish I had more money.
What size is that? The reason for the questions is that I am thinking about a bigger intake valve. And I would like to go to around the 11- 11.2 to one or so. I asked this question before but I don't know how high a guy could take the compression and still run 93-94 octane? I would like to take it to that piont. The valve I was thinking of would be 2.2 or so.
alhall88
UAW
The stock valves that were in my 04 were 2.0 for the intake and 1.605 for the exhaust, which is the stock size for a true 117 S&S. The builder johnsachs in this thread is using a 2.020 intake valve with his builds. As far as I know I would have to say that 10.8 maybe 11.0 would be the limit on pump gas. I'm running 10.8 and the timing at 28 BTDC. If I throw any more than that at the advance it will start to ping.
MARV
Well-Known Member
no just 93 octane.
plugs look good with no sign of detonation, as far as i can tell.
i'll do another ccp test to double check that 206 psi.
I'd shoot for the 10.8 to 1. A half point of compression isn't going to make much difference power wise and could cause problems on pump gas. I would think it's possible that running less compression and more timing would yield more top end power. Is 28 normal on these V twin builds? Or is that just to prevent detonation? I don't know how these ignitions are set up on V twins but for instance on my Camaro if I could only go to 28 total that would only give me 7 degrees initial timing which will really lower my engine vaccum at idle and make it run like dog shit in the low rpm range. Low vaccum effects the signal to the carb especially with a larger camshaft. Generally you want to bring your timing in as soon as possible without detonation. All my knowledge is car related so step on my toes if I am way off here.
dogvet
Banned
Free flowing pipes will cause a dip in the 2000 rpm range. The ripple in the graphs would indicate that either you have a pushrod that isnt quite adjusted right or you have some slop in your primary chain.Everyone:
I have attached a dyno sheet that shows some fairly respectable numbers. Testing was taking in Nebraska at 2,800 ft of elevation.
The baseline numbers are a 117 with a S&S 600 cam, XXX Carb, V&H 2 into 1 pipe, and powerpacc carb backing plate.
The new results are after changing to a woods 650 cam and springs, Hooker Fourbidden pipe, zero deck height, and Thunderheart Ignition.
A note worth mentioning, is we dyno'ed the bike using the 3, 4, and 5 settings on the ignition and it showed only a small difference between the 4 and 5 but it did not like the 3 at all.
These are numbers with the air filter on, we did gain 3 hp and 2 tq by taking off the air filter
The dyno guy did say the dip is due to the engine needing more back pressure and the normal problems associated with running an Super g carb.
Life's good, run's great
K9 Husker
barhopper
Another round please
Head work it good, makes it breath better. Need good air filter too. A motor is alot like a BJ. The better the girls breathes through her nose(air filter) as she is doing the deed, the better(never comes up for air) and faster she she gets the prize. By the way, I run a 650 woods cam.
Beastman1652
Team O.M.A.B. Prostaff
Very nice relation!:up:
BorgerBigDog
BORN TEXAN
You people are making me spend more money !!! This will be fun to get done...
Black Dawg
Active Member
Nice power. A friend had a similar looking graph with the torque dip using VH pipes and by switching to RB Racing LSR's he eliminated it.
HDLARRY
Active Member
Nice peak numbers even if it does have the dip. Looking at your base numbers while using the V&H 2-1 I don't see much if any dip. Only after making the changes did the dip show up.
I'm running 05 117", 10.5:1, 600 cam, XXX carb w/Thunderjet and RB Racing LSR 2-1 exhaust. My torque curve is similar to your base curve without the waves and peaks about 3600 RPM.
My experience would say that a 2-1 exhaust would remove a lot of your torque dip. The graph does not show the AFR but if it was normal, a 2-1 exhaust should solve everything. If the S&S carb AFR was not good and could not be adjusted out, then a Thunderjet or replacement carb with a 3rd circuit might be in order.
I'm running 05 117", 10.5:1, 600 cam, XXX carb w/Thunderjet and RB Racing LSR 2-1 exhaust. My torque curve is similar to your base curve without the waves and peaks about 3600 RPM.
My experience would say that a 2-1 exhaust would remove a lot of your torque dip. The graph does not show the AFR but if it was normal, a 2-1 exhaust should solve everything. If the S&S carb AFR was not good and could not be adjusted out, then a Thunderjet or replacement carb with a 3rd circuit might be in order.
Black Dawg
Active Member
That torque dip tells me that there is a distinct lack of scavenging happening in that rpm range. Usually drag or non-collector style pipes are known for this. I have no idea what the real story is on those Hooker Fourbidden pipes, but your dyno is showing a problem.
I'd have to question the intermediate or main jet personally. Maybe both. That is right in the transition slot and a difficiency in either would cause a problem. I'd lean towards the intermediate jet here. Hard to believe exhaust would cause a dip in power. Flatten out maybe.
Black Dawg
Active Member
Look at his before torque graph. It has a more normal curve without the pronounced dip and he was using a 2 into 1 exhaust. His major changes were the cam and exhaust. With the larger cam exhaust tuning becomes even more critical.
He should try swapping exhaust to the previous 2 into 1 and redyno or just go for a ride. I bet it is a night and day difference.
He should try swapping exhaust to the previous 2 into 1 and redyno or just go for a ride. I bet it is a night and day difference.
HDLARRY
Active Member
I agree with BD