heads or big bore

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heads or big bore

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heads or big bore - 3/25/2008 3:12:18 PM

evolution12c

Posts: 4
Joined: 3/19/2008
Status: offline

Hi guys I am in England and am new to the forum,we have very few experienced HD specialists over here. I know this subject has been coverd alot, but I'm more confused now. I need more power out of my 1993 fatboy, current spec, Crane Hi 4 single fire, air cleaner, EV27 cam, CV carb Yost kit, 2-2 exhaust soon to be 2-1. I was reading the engine build on the nightrider site stage 3. SE heads 83 Hp 87 Tq, good results, heads are cheap, the more I look through the HDforum I get more confused, i can spend more money so always like to see whats out there, S&S super stock kit comes recommended but is $3-400 more and you need to change pistons, S&S specs is 81Hp and 83Tq, lot more money and work for less HP if the nightrider site can be trusted.I have looked at RP big bore kits, getting my heads done. Not sure, I travelling to florida in sept, getting married thought I'd try and pick up parts while I was in the state. anyone recomend any good dealers. standard head work seams slow and unreliable, many claims out there.
I know S&S are quality but the SE heads are supposed to be good, also edlebrock are mentioned.I need advice from guys who have done these conversions, should I go the simple route with the SE heads or spend a little more money and get more bang!! I still want reliability, Any help please guys would be appreciated.
andy

Post #: 1

RE: heads or big bore - 3/25/2008 4:55:07 PM

Buddy WMC

Posts: 166
Joined: 4/13/2007
Status: offline

Hello There,
I have a similar setup to yours presently on my FXR. I have collected all of my parts and intend to tear down the top end in the next week ot two. I am installing the R/P 85" cylinders/CP piston combo with ported SE heads, a V-Thunder EVL 5015 cam, V-Thunder lifters, TP roller rockers and S&S rocker boxes. I have a dual/single fire Dyna ignition system and will go over everything.

I am associated with a R/P dealer, so to be fair it can not be said that I do not run what I sell. I have spent alot of time and have spoken to alot of different people. This combination ought to run extremely well. When all said and done, I probably would have been better off financially purchasing a new engine and keeping the original.

Larry's Motorcycle and Machine in Oak Lawn Illinois, performed the head work on the SE heads. There are many competent folks in the business. Larry knows what to do to make the right type of improvements to the SE heads. He also does what he says, is honest and gets the work finished on time. The SE heads when ported like to flow the best at higher lifts, hence my cam choice withoout loosing all of the bottom end. I hope this has been helpful and not more confusing for you. Visit us in Florida or on the web at WWW.choppersspirit.org.

_____________________________

1993 FXLR S&S Super E, Andrews EV-27, SE Chrome Lifter Blocks/Lifters, SE Ignition,SE Pushrods. WFFW!!

(in reply to evolution12c)

Post #: 2

RE: heads or big bore - 3/26/2008 5:36:37 AM

grbrown

Posts: 187
Joined: 6/29/2007
Status: offline

Hi Andy,

It is easy to be confused with what can be done! I am also in England and have owned Harleys since the 1970s. My 1990 FLHS currently has a JIMS stroker kit, high comp pistons, ported heads, etc, but will shortly get a new S&S 107 engine. I have been down the EV27 route, similar to you.

There are actually limited choices available. You mention big-bore kits, but I think your crankcases suffer the same short-comings as mine, and are not suitable for boring out, as the castings are too thin, hence my stroker kit. Indeed if you tune the engine highly there is also the risk of stripping the cylinder studs, even shaking loose the drive-side main bearing! I reckon I have pushed mine about as far as is sensible, hence the new motor.

So unless you are willing to fit replacement cases be wary of tuning too highly. New or modified heads with new pistons are straight-forward, ditto cam and carb, but decide what you want to use your bike for before getting too enthusiastic! Most of us ride the bike below 4,000rpm, whereas many engine mods will only give real improvements above that. I have chosen my 107 because it is expressly tuned for touring, and has better low down torque than a 124!

As you have just discovered HDF, spend some time browsing, as you will find plenty of info here!

_____________________________

Graham - 1990 Bright Candy HiFi Blue FLHS/2008 S&S V107T, 2007 XB12R, MG ZT V8, England.

(in reply to Buddy WMC)

Post #: 3

RE: heads or big bore - 3/26/2008 12:24:18 PM

evolution12c

Posts: 4
Joined: 3/19/2008
Status: offline

thanks for the advice, do think i will probably go with SE heads and 85" RP kit.
andy

(in reply to grbrown)

Post #: 4

RE: heads or big bore - 3/26/2008 1:31:55 PM

evolution12c

Posts: 4
Joined: 3/19/2008
Status: offline

Hi guys, just been directed to cyclerama's website and they have some high horse power claims for evo's,113Hp from head work and cam, you guys have any experience of these guys, say they have been in buisness since 1976, seems to good to be true.

(in reply to evolution12c)

Post #: 5

RE: heads or big bore - 3/26/2008 4:02:26 PM

Hackd

Posts: 1338
Joined: 10/7/2005
From: Canton, Michigan
Status: offline

Not to rain warm yellow water on anyone's parade, but it really seems to boil down to what you want your bike to do.

I've got a 'stock' EVO (1993 FLHS), slight overbore (with the new top end), stock heads that have been street ported, EV27 cam, SE air cleaner, Dyna 2000 ignition, and SuperTrapp slipons with 18 discs. My bike does everything I want it to do, will do it day in, day out. And get 40+ mpg. Two-up, loaded (I pack a lot), 70mph, and in the wind.

Ya want to race 'light to light': Dump the Fatboy and get an FXR.

_____________________________

In the end...It's all Hack."
______________________________________________

(in reply to evolution12c)

Post #: 6

RE: heads or big bore - 3/26/2008 4:43:07 PM

Buddy WMC

Posts: 166
Joined: 4/13/2007
Status: offline

quote:

ORIGINAL: Hackd

Not to rain warm yellow water on anyone's parade, but it really seems to boil down to what you want your bike to do.

I've got a 'stock' EVO (1993 FLHS), slight overbore (with the new top end), stock heads that have been street ported, EV27 cam, SE air cleaner, Dyna 2000 ignition, and SuperTrapp slipons with 18 discs. My bike does everything I want it to do, will do it day in, day out. And get 40+ mpg. Two-up, loaded (I pack a lot), 70mph, and in the wind.

Ya want to race 'light to light': Dump the Fatboy and get an FXR.

Yepper,
Won't disagree with Hackd's comments. There are alot of trade offs and personal choices with engine builds. After the kit is installed, we get some breakin time and minor jetting changes it will be off to the dyno. Then we'll see what this old FXR has got or doesn't have

.

_____________________________

1993 FXLR S&S Super E, Andrews EV-27, SE Chrome Lifter Blocks/Lifters, SE Ignition,SE Pushrods. WFFW!!

(in reply to Hackd)

Post #: 7

RE: heads or big bore - 3/27/2008 5:42:48 AM

Van_Kerr

Posts: 26
Joined: 3/7/2008
Status: offline

Lookin' forward to the dyno results ......... what will you be happy with ? Must be a figure in mind. Will you leave it alone then ?

(in reply to Buddy WMC)

Post #: 8

RE: heads or big bore - 3/27/2008 9:43:00 AM

dog155

Posts: 4656
Joined: 11/5/2006
From: Windham,Maine--God's Country
Status: offline

The bottom line is how do you intend on riding your bike.Big grunt comes from big cubes.If you want to buzz the motor all the time do the head work.In all years and experimenting, the best bang for the buck comes with big cubes Period

(in reply to Buddy WMC)

Post #: 9

RE: heads or big bore - 3/27/2008 2:18:05 PM

evolution12c

Posts: 4
Joined: 3/19/2008
Status: offline

I appreciate all your advice, I could not agree more with hackd, I do realise that your use of the bike is important I am just trying to see all my options.thanks

(in reply to dog155)

Post #: 10

RE: heads or big bore - 3/27/2008 4:47:41 PM

Buddy WMC

Posts: 166
Joined: 4/13/2007
Status: offline

quote:

ORIGINAL: Van_Kerr

Lookin' forward to the dyno results ......... what will you be happy with ? Must be a figure in mind. Will you leave it alone then ?

I'll be more than pleased with 1 HP per cubic inch at the rear wheel. My consultants think that this is attainable and realistic number. If it is less, so be it and perhps the dyno should tell us how to improve. If it is more, I'll be more than pleased.

Yep, after this I'll leave the engine alone. I may play with the gearing some to drop the RPM's some more.

_____________________________

1993 FXLR S&S Super E, Andrews EV-27, SE Chrome Lifter Blocks/Lifters, SE Ignition,SE Pushrods. WFFW!!

(in reply to Van_Kerr)

Post #: 11

RE: heads or big bore - 5/6/2008 3:39:40 AM

Buddy WMC

Posts: 166
Joined: 4/13/2007
Status: offline

Hi All,
Just thought to update this a bit as I finally got the lift time. The engine was torn down before Leesburg, so no progress as the shop was closed. Found some interesting thigs during the treardown.
(A) At some point in the bike's life the head and rocker box gasket were replaced with non HD parts.
(B) the paper base gaskets just fell apart when removing the cylinders. Most of the brittle paper came off with the cylinder. Very little cleanup needed on the cases. It is esy to see why so many have weeping/leaking problems here. We will be installing the oil fix along with the new Cometic base gaskets sometime today.
(C) I switched from Dino to Redline synthetic oil (against some advice here), when I purchased the bike. I know that the previous owner also performed early mile oil changes.The inside of this engine is very clean and the rod/piston pin clearances are right on the money. Shows to me the good oil and oil change intervals do make a difference.

On Saturday we clearanced the cases for the .595 lift V-Thunder EVL-5015 cam. This cam was recommended by my head porter and the selection was confirmed as a good choice by Comp Cams and Revolution Performance as the ported SE heads flow best at higher lifts. We also checked the lifter to lifter block clearances and needed to make no modifications to the SE Lifter blocks. After thouroughly cleaning out the cam chest several times, the new V-thunder cam, V-Thunder lifters and current S&S reed valve breather were reinstalled.

Cam cover seal was replaced and the cam cover was reinstalled using a new James gasket. The bottom end was buttoned up by reconnection of the ignition sensor and cover plate. We also replaced all of the 15 year old oil lines, seals and vacuum lines. We also did discover a pretty serious rusty area under the seat mounting area and will be addressing that repair.

Stay tuned for part II, hopefully the 85" top end, SE heads, S&S rocker boxes, TP roller rockers and valves should be adjusted by tonight. We are shooting for a Wednesday start up and engine heat cycling program.

_____________________________

1993 FXLR S&S Super E, Andrews EV-27, SE Chrome Lifter Blocks/Lifters, SE Ignition,SE Pushrods. WFFW!!

(in reply to Buddy WMC)

Post #: 12