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[i2zh2o]

is anyone running theses cams in there twin cam motors and checked there cranking compression what should it be?

[DCFIREMANN]

Yes I am and have been running and installing these cams in TC motors for a while. Cranking compression will vary. The type of piston, type of heads, mods that have been done to the heads, what combustion chamber size and style.

It still should be around 180 lbs.

Be Safe

THE DAWG 

[i2zh2o]

well is 170 to low i was hoping for 200 it just dosent seem to run that well email me would like to talk so i know what the next step is the motor has 11 to 1 wanted 11.5 but didnt get that was thinking about going to s&s 625 cams

[DCFIREMANN]

I have a few questions for you.

What motor and what heads are you running. If you are running a stock combustion chamber CVO head that is why you are at 170. 170 is not too low but IMHO 200 is too high for a street bike. The 640's are a great set of cams but they need head work and compression to work well. The 11 to 1 compression you are running is uncorected compression ratio. It will go much lower with a set of cams like the 640's because of the over lap. What motor and what other mods are you running.

Be Safe

THE DAWG

[i2zh2o]

motor 120 jims with revolutoin 135 kit with ported and milled and welded up heads and 56 hp efi

[DCFIREMANN]

On a 120 motor the 170 cranking pressure should be just fine. Part of the problem might be the throttle body. What fuel injection mangement system are you using?

Be Safe

THE DAWG

[i2zh2o]

 R T Screamin Eagle

[DCFIREMANN]

Has it been retuned since the build? If so what numbers?

Be Safe

THE DAWG

[i2zh2o]

very low i think 120 hp 116 tq fuel set at 13.2

[StreetDog]

  DCFIREMANN, I am new to the site and you seem to be well informed. I have a question for you about some mods I'm having done. I want to know for sure if the dealer is telling me right. I have the 110 motor. I am putting on the D & D Fatcat 2 into 1 (w/ ghost pipe for looks) a K & N air filter, SERT, and I wanted to change cams. For any other changes I would like to stay with HD parts. The dealer said I will need to do some head work and change pistons for more compression if I change cams. The mods they are suggesting are to go with the 258 cams, do clean up work on the heads in behind the valve and ports. Cut valves seats 15 degrees. Change to the NEW piston for the 110, it's a forged hard anodized and Teflon impregnated 10:25 piston, black ( just came out ). New adjustable pushrods and clearance the rocker boxes. They said that would be a good package for me with durability and longjaivity ending with 10:50 compression. Do I also need to add the compression releases tapped into the heads? What do you think about all the mods, and is this the right way, or OK way to go? Anyone else's thoughs in this matter?

[geezerglide]

12zh2o,

You and I have spoken before, I never got back to you with the CCP, reading this post reminded me, it is 180. Compression is 10.75.1.

I think you have SBC's Vortec heads, probably similar or same as mine.

You mention 135 Kit, what is that.

My build is the Jims 120, Heads Vortec Grind by SBC, S&S 640 Cams, rest of engine is stock. Kurayakyn 57 mm TB c/w 6.33 injectors. HD SERT Custom Map by Lee Uhrich JARZ Performace, that took all day to set up. V&H Pro Pipe, soon to change back to Freedom Cycle True Duals. HD Six Speed Transmission.

Engine dyno at 131 hp and 134 lb ft TQ.

Dyno Sheet attached

geezerglide

[i2zh2o]

yes i have the same thing as you but something didnt come out right because i only got 160 with that set up so i changed it sbc did the work and still didnt get it right i just dont under stand not happy spent more money and got nothing in return wanted 11.5 and i got like 11 or less i guess i will just have to learn to like it or send my heads somewhere else to get what i need to make it work :nixweiss:or change cams 130 hp or even 140 like they said it would be is a long way off

[DCFIREMANN]

  DCFIREMANN, I am new to the site and you seem to be well informed. I have a question for you about some mods I'm having done. I want to know for sure if the dealer is telling me right. I have the 110 motor. I am putting on the D & D Fatcat 2 into 1 (w/ ghost pipe for looks) a K & N air filter, SERT, and I wanted to change cams. For any other changes I would like to stay with HD parts. The dealer said I will need to do some head work and change pistons for more compression if I change cams. The mods they are suggesting are to go with the 258 cams, do clean up work on the heads in behind the valve and ports. Cut valves seats 15 degrees. Change to the NEW piston for the 110, it's a forged hard anodized and Teflon impregnated 10:25 piston, black ( just came out ). New adjustable pushrods and clearance the rocker boxes. They said that would be a good package for me with durability and longevity ending with 10:50 compression. Do I also need to add the compression releases tapped into the heads? What do you think about all the mods, and is this the right way, or OK way to go? Anyone else's thoughts in this matter?

I don't know that I would spend all of that money on that package. The dealer is doing that package because it is all HD. I would have the heads done by some one who has a CNC machine with a program set up for the CVO hemi head. This would be a head set up and it would be tried and tested. I would not use a chain driven cam at all. And since Harley doesn't make a gear driven cam that would end the project for me.

But that is just my opinion.

Be Safe

THE DAWG

[hd-dude]

I don't know that I would spend all of that money on that package. The dealer is doing that package because it is all HD. I would have the heads done by some one who has a CNC machine with a program set up for the CVO hemi head. This would be a head set up and it would be tried and tested. I would not use a chain driven cam at all. And since Harley doesn't make a gear driven cam that would end the project for me.

But that is just my opinion.

Be Safe

THE DAWG

I've got to agree here, until HD comes out with a performance gear driven cam (which I doubt they ever will) I would not ever consider them.

[geezerglide]

i2zh2o

I don't know why you are blaming SBC, I got probably the exact same heads and I have had no problem and now have over 13,000 miles since the build.

The only difference I can see is SBC reassembled the whole Jims 120 c/w the modified heads. Originally had the stock HD TB and injectors and a "canned" SERT Program. Then only dynod at 120/121, after addition of the Kurayakyn TB and large injectors and a compltely new custom remap did I get the increase in HP and TQ.

Also other difference are the Pro Pipe 2:1 which probably is better than the dual system.

The only recommendation I could/would make is to find a qualified tuner (not just a Dyno Operator) who knows the HD SERT inside and out and is capable of setting up a custom MAP. And, I am knocking whowever your tuner is, just make sure he knows the HD SERT or if you decide to try Zippers Automax systems and how they can be best tuned for your individual bike.

I drove over 1,200 mile both ways to a "qualified tuner" just to get my bike tuned properly.

I would try and find out where Doug Lofgren (Ex Kuryakyn) is now, I think somewheree in Wisconsin, he is excellent in EFI tuning with anyones systems. If you can get in touch with Mike Roland of Kurayakyn he may lead you in the right direction.

Just some thoughts as I know you have been tryiing to resolvethis HP and TQ issue for quite some time.

geezerglide