how to grinding or modify an stock camshaft for single cylinder engine (ie honda xr200)?

Answer 1

Wow!,,I never realized there were so many experienced cam experts here!

I cannot blame them for being reluctant to explain "How To",,,it's a Big,Long Story.
And Honestly,,the Entire Story "needs" to be fully understood.

I'll side with everyone else ,,,I dont have the Time either,,,
and Yahoo may not have the bandwidth anyway,,lol.

.......................................
But,,I DO have a few minutes to spare.

And if You are only interested in "Experimenting" and do Not have a Strict,Firm requirement for the resulting performance change,,,,I will be happy to tell you the Basics of how to Modify your own cam,,at home,,with simple tools & supplies

Tools:
*Power Drill with a 1" Wide grinding wheel--medium grit
-A Bench Grinder is Really TOO agressive,,,but Can be used if VERY Careful
-a "Sanding Drum" in a drill is Slow,,,which may be Safest of all grinding options

*A NEW fine cut Mill File,,,just a common "Mill Bastardd File"

*some 180,,320,,400 Wet/Dry sandpaper

*A New Sharp Drill bit,,for re-drilling cam sprocket holes

*A Dial Caliper
--Also,,a Dial Indicator sure helps a Bunch,,but aint absolutely necessary

*"Dykem",,,Layout Dye....this is a Thin sorta Ink/Laquer you apply to parts.
It's dark navy blue,,,and drys Instant---almost like a Magic Marker.
But the coating is VERY fragile,,,and will be Marred or rubbed away by anything which rubs on it.
It allows you to See where Contact is being made.
You can use Magic Marker,,,but it's pretty tuff coating when dried.
You NEED it to find "beginning and End" of Cam Lobe.
Rocker Arm Contact "Marks those spots" for you,,on the cam.

..............................................................................
The simplest "beginner Level" ReGrind that show Good Power Gains,,,let engine pull Harder and Longer thru each gear involves only 2 Simple changes.

1)Gross Valve Lift,,involving the CAM itself
2)Timing of Intake Closing Point,,involving Only the GEAR

It is NOT at all a sophisticated improvement,,
but it WILL show Good gains,,,and is easy and safe to do.

We'll look at them separately.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Altering VALVE Lift.
Several Books worth of Bullshit all boils down to One Simple Fact.

"There Is A LIMIT to Valve Lift"
You can spend several years of your Own time,,
if interested in Fully understanding all that.

For NOW,,we wanna Get to Grinding,,Make some Horsepower,,and Go RIDE.

So OUR Limit will be about +1mm Valve Lift,,over STOCK.
That's Only .040",,,,about the Thickness of 2 or 3 beer can pop tops.
It's SMALL.

So How do we get the Cam to Raise the Valve HIGHER,,but cutting the Cam SHORTER?
That Sounds like Doing OPPOSITE thing,right?
To Undo an Opposite,,,we do ANOTHER Opposite,,,LOL

Ok,,Picture a CAM LOBE.
It's basically an EGG SHAPE,,,not an Oval.
Fat on Bottom,,,Pointed on Top
Like a Triangle sittin on a Circle

The Cam Lobe's CENTERLINE is the center of the Circle.
The LOBE--The Triangle ,,,is actually "The Cam"---it's OFFSET and as it comes around it Lifts the Valve

Directly OPPOSITE the PEAK of the Lobe,,,is called the BASE CIRCLE.

Valve Clearance is Adjusted AT the BASE CIRCLE position.
That's ZERO LIFT,,,the "lowest" point on the Cam.

Imagine an assembled engine,,with Valve Clearance Set AT the Base Circle.
NO lifter/rocker contact,,Just SPACE.

As Cam Turns,,,,the Lift Ramp comes around,
It takes up the space,,and eventually comes around to Max Lift,,,up at the Lobe's Peak.

Now,,go back to Base Circle,,,with Correct Valve Clearance Set.
CUT THE BASE CIRCLE "SHORTER",,,just "grind it down".

See the Extra Clearance ya just cut between Cam & Rocker arm?

If You Turn the Cam around to Lobe Peak,,,
The Valve Lift DOES NOT CHANGE.
Because WE Did NOT RE-ADJUST the Valve Clearance.

But if You Grind the Base Circle>>
Increase the Gap between Cam & Rocker..
Then RE-ADJUST the Valve Clearance to remove that Slack,,,
ROCKER Moves INWARD towards Cam's Centerline,,in order to regain proper valve clearance.

So when Cam turns around From REDUCED Base Circle Radius,,,and TO the LOBE PEAK,,,
The Rocker Arm has been RAISED a Relatively HIGHER Distance.
Result= Higher Valve Lift.

We Cut Base Circle LOWER,,,Readjust Valve Clearance to remove that slack,,,and then Valve Lift is HIGHER.

Important:
Because we are dealing with a RADIUS--Half the Diameter--,,,
The Net Valve Lift will be TWICE the Amount we Remove.

To get our .040" GAIN in CAMSHAFT Lift,,,
We only Need to Remove .020" From Base.

Cam Lift and Valve Lift are 2 Different things,,because of Rocker Arm Ratio.

The ROCKERS MULTIPLY the CAM Lift.
I do Not know what a XR200 Rocker Ratio is.
Most are about 1.5:1

So if CAM LIFT is increased .040",,,
Valve Lift with 1.5:1 Rockers will be .060".
1.5Times the Cam Lift.

In that example Removing .020" from Cam Base Circle yields a .060" Gain in VALVE LIFT

You can See the REALITY of How LITTLE must be REMOVED to get a substantial gain in Valve Lift.

.015 " grind-away =.030 Cam Lift= .045" Valve Lift w/ 1.5 Rockers.

So,,,All You Really wanna REMOVE from CAM is .015~.020" MAX.

(Recall what I said about Bench Grinder being TOO AGRESSIVE?? Make any sense now?)


But WHERE To Grind?.
That is ANOTHER Huge Subject we are gonna Over Simplify down into USEABLE,DO-Able Terms.

Changing the SHAPE of the Base Circle alters the Action of the Cam's Lift.
How QUICK it Lift's.
How SOON it Lifts.

Short example:
a) If You Simply file FLAT,,,Straight across the Base Circle,,,
You DO get the Extra Valve Clearance.
But it's a Very Narrow flat angle across Cam.

That Means as the Cam Turns,,,it will be OFF the Flat Spot very SOON & begin to Open Valve.
'Cuz it's coming UP to the Old,Normal Position very Suddenely in terms of Rotational Degrees.
And when it's Closing the Valve,,,it Holds it Open Longer/Later till it finally reaches the Flat Spot we cut,,,,so Valve can Close and have some Valce Clearance again.

B)But Instead of a Simple ,,Straight -Across Flat,,,,,
We work to FOLLOW the Original Base Circle's ARC,,,and grind the entire Distance Down,,,
That Opens Valve LATER,,more Similar to STOCK specs.
And it opens valves Slower and more Gently

Very Careful Measurement and Careful Work can produce a Cam which is Identical to Stock TIMING Specs,,,but has a Higher Lift.
You must Closely RE-Radius entire Base Circle.
That Increase CLEARANCE needed to generate the LIFT,,,but introduces the Ramps at Same Points as Stock.

Filing "A FLAT,,Straight Across" the Base Circle effectively NARROWS the Base ,,,which introduces Ramp SOONER.
So you get Extra Lift AND Longer Duration.

This is a matter of Advanced Design,,,,but You can Also Grind a "TRIANGLE" on the Base Circle.
Other than a Simple ARC or FLAT

Like: /I or I\
Bad Picture,sorry.
But it's sposed to show that You can Start at Different Points on The Base Circle.
Either END,,,the Middle,,wherever.
And grind down at an Abrupt Angle.
That Chnages TIMING,,,and also Open/Close RATE-OF-LIFT.
That gets VERY Complicated and includes a BUNCH of MECHANICAL Considerations.

A SIMPLE AVERAGE is Easiest to DO and hardest to screw Up or Go Wrong.
BIGGEST PLUS is that all You're doing is adding Clearance in NON Contact AREA.
So the Matter of Hard-Surface on Cam Lobe,,and cam Wear,Rocker Wear is a NON ISSUE.

Stuff that Dont Touch,,Dont Wear,,right?
Soon as the Clearance is Gone and Rocker begins to take a Load,,,it's Back upon ORIGINAL SURFACE.
Cool,huh?

So I'll Skip all the Home-made Hardening Techniques,,,because they're Totally Unecessary.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
INSTRUCTIONS:
A) Use Dial caliper To Measure Lobe and find it's Greatest "Diameter".
That Means you'll measure from Base Circle to Lobe Peak.
Sorta "Roll " Cam back/forth to find Highest Possible Point//Largest Distance.
DOES NOT MATTER "Where" it occurs,
All we care is the DIMENSION,,,The MAX DISTANCE across the cam lobe.
Find that and Write it Down.

When we start CUTTING,,,we will want to SHORTEN that Dimension by about .015"

B) "Paint" the Lobes with the DYE mentioned above in "Tools Needed"

C) Turn Crank to get Piston DOWN outa the way,,,
Slip Cam Into Head with Both Lobes pointed "DOWN".
That is the Install Position,,And the Valve Clearance Adjustment Position,,,And puts the BASE CIRCLE next to the Rockers.

DONT TURN THE CAM YET,,because ya DONT want it rubbing on Rockers and messing up your new DYE "paint job"

D)Adjust the Valves to Factory Specs.

E)NOW,,Turn The Cam all the way in One Direction,until You feel RESISTANCE.
That Resistance means All the Clearance is Gone and Rocker is at Foot of the Ramp.
Wiggle Cam Back & Forth to Cause the Rocker to Scratch Up The DYE on the Cam's Lobe.

Then Turn Cam all the way in Opposite Direction,,,and do same thing.

When ya REMOVE the Cam after Doing That,,,
You will see a place on the Base Circle of Each Lobe where the DYE has been Scratched.
AND a "band" where it has NOT been Touched,,because Valve Clearance kept Pressure OFF the Rockers thru that area.

The UNTOUCHED Part is The Base Circle's Beginning and End,,between the foot of Opening and Closing Ramps.

F) THAT is the AREA to GRIND the .015~.020" away from

E) You can estimate the CENTER of that Untouched Area,,and Grind or FILE a Straight Flat SPot across it.
Then Blend each end Gradually into Overall Circle.
So that your FLAT SPOT becomes a wide radius ARC

That will most closely Duplicate /Retain STOCK TIMING,,,while ADDING LIFT

F) Or You can Start Filing at One END of the Base Circle,,,and Gradually Taper the Arc into the Ramp on Other End of that Untouched Dye Area.

ACTUALLY,,You are BEST to CENTER your Flat Spot,,,File it Down to Desired Dimension,,then Blend each end into a Arc .
That Avoids a buncha potential probs with Lobe Centers,,,Open vs Close Points,,,Lifter Accelerations and all sorts of other crap

You'll STILL gain a Bit of Symmetrical Duration,,which is OK..good actually.

Only reason I mentioned OFFSETTING the "Flat" is to Reassure You there's a Wide Range of Specs possible,,,
So Being PRECISE is not really much of a big deal,,,,in terms of having Plenty Margin for Error.

DO NOT,,N-O-T Cut ANYTHING except the Base Circle.

Check the Cam's "HEIGHT" against your orignal measurement.
Cut a little,,CHECK IT,,
Cut some More,,and Check Again.
A LITTLE is GOOD,,,TOO MUCH= TRASHED.

A Sharp New FILE should cut a stock honda cam.
TRY the File First.
If somehow it's too hard,,,it will Only be VERY SHALLOW,,surface hardness.

Usually some initial Sanding with Medium-Course Paper will remove the hard coat,,,and a File can take it down from there.

Obviously,,You gotta cut it as "square " as possible following the original lines of the lobe.

Bike Cams DONT have Tapered Lobes like Flat tappet Car Cams do
Bike Lobes need to be "Square" with their Rockers.

Forget about being PERFECT,,,but DO your best.
Remember,,it's "Just Space",,nothing ever touches where You'll be Cutting.

G) Finish the Job by Polish the grinded are and blending it into the UNGROUND are with the Wet/Dry Paper.

DONT go OFF the Base Circle,,,and onto the ramp any more than Necessary.
Use Corse>Medium >Fine paper,,it DONT have to even be "NICE",,let alone Perfect.
WHY NOT??
Because,,,NOTHING TOUCHES,,not with any Load anyway.
And at the Juntion where Basecircle meets Foot of RAMP,,,the Load is extremely LOW.

And as a Final Prep,,,,LIGHTLY but Thoroughly POLISH the entire Lobe with with some OILED 400 Grit.
That will leave a very faint matte finish ,,,which is far better than High Polish/BURNISHED the way they get after running a while.

Do exact same Polishing with Oiled 400 grit on the ROCKER ARM pads where they contact the cam.

Very ,VERY LIGHT polishing on the Bearing Surfaces is Good also.
Take some Worn/Used 400 Grit,,,Rub it together to lower it's abrasion,,,Risnse with Soapy water to clean it,,,
THEN use the weakened 400 on the Cam Bearing Surface,,LIGHTLY.
Or just buy some 600 or 1000 grit and use that,,oiled.

Wash the cam in soapy water,,Spray with WD-40 and wipe dry.
All Done with That.

You NOW have a Ready to Go Hi-Lift Cam,,,
with Who Knows How Much extra Duration?? LOL

Shouldnt take more than an Hour or So,,including Remove /Replace cam.

BE CAREFUL,
GO SLOW and MEASURE OFTEN.
.015~.02" is SMALL.
DO NOT get Tempted to "Go Further".
A SMALL Screw Up is OK,,,BARELY.
Too MUCH can cause BAD physical interference probs.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Part 2: TIMING

All ya Gotta do is RE-DRILL the 2 Cam Sprocket Mounting Holes in a Different Place..

THis is a SMALL DIFFERENCE,,dimension/position-wise.
But a BIG difference in how engine runs.

You can drill several sets of holes if you want too,,,while Your at it.
It's gives you a tuneability option of a few choices,,,and it's fairly easy & quick to Change.

OK,,,Stock Cams can almost Universally be re-indexed up to 10 Degrees.
Some engines can Physically accomodate much more..
But JUST as Universally,,,it is Considered that even 10 * is "Too Much" of a Change.

Or the way it's Usually stated,,,"If You Gotta go MORE Than 10*,,,,then You Got the WRONG CAM PROFILE and NEED to change the whole cam to a totally different one"

That's "True" for a lotta reasons,,Mostly because while SOME SPECS are Improving as Cam is Moved further,,,
OTHER Specs are getting "Worse".

Every Cam has a RANGE besides simple factory Install settings.
Outside that Range of "ADJUSTABILITY",,,it begins to upset the particulary cam's Balance of Specs.

So,,for SIMPLICITY we'll stick to a 10* Max cam timing change.

YOUR CAM SPROCKET has 32 Teeth.
It Runs at HALF of Crankshaft Speed.

One Full CRANK turn= 360* and produces 1/2 Cam turn.

So Twice That,,720 * = 1 Full Camshaft Turn

720* divided by 32 Teeth = 22.5* Per Tooth.

If You just Moved the Cam Timing by 1 Full Tooth,,,it would produce a 22.5* Crankshaft Offset

Which is over TWICE our 10* "Limit".

Therefore,,,You CANNOT move Cam Gear 1 Whole Tooth.

You can only go 1/2 TOOTH from the factory mark.

No Way to install a Camchain on a HALF-TOOTH position.

But if we RE-DRILL the Cam Bolt Holes,,,,1/2 Tooth different from their Original Position......
When we install cam and Line up all the Marks "By the Book" that puts CAM in a DIFFERENT PLACE.
1/2 tooth Offset,,about 11.25*

1/4 Tooth = about 6*
3/8 Tooth = about 8~9*

3/8 to 1/2 Tooth is about MAX you can move the cam timing.

That's a TEDIOUS thing to do,,,,but it's EASY.
And like the rest of our Ax-Murderer Style Hop-Up Experiment,,
It DONT have to be PRECISE.

"O" timing is factory Specs,,,+2* is Better,,+4* is Better Yet,,
What's BEST,,IDEAL??
Who CARES?
About 10* is all ya really WANT to try.
If You are Aiming at 10*,,,and you end up with 8.5* or 11.5*,,,
Oh Well----it's STILL in Ballpark,,,even if NOT OPTIMUM.

You can spend $150 on a REAL CAM,,,,cut to some TESTED SPECS,,,or CALCULATED SPECS,,,but all just ARBITRARY,RANDOM SPECS.

A REAL CAM EASILY may not be as Near Optimum as Your Sloppy Drilling 2* Screw -Up is.

Because without Extreme,Extensive Testing of a SPECIFIC ENGINE,,,,
There Is NO "Right/Wrong".
Even an EXCELLENT Cam,,,the BEST CAM available,,,,is almost Always "Only CLOSE".

Goofy as that sounds.
It's NOT as Precise detail as many folks imagine.
If You get Within a RANGE,,,that's GOOD ENOUGH and "perfection" offers very little Useful difference.

You gotta be STOOPID waaaay -Off before ya can actually Hurt anything,,,both Physically And performance-wise.

>>>>>>>>>>>>>>>>>>>>>>>>>
HOW-TO Mod Cam Sprocket.

a)Use a Good straight-edge Across the center of Both Holes to See their Relationship to the TEETH.

Usually the Holes are Centered BETWEEN the Teeth.

b)Move to a Different Tooth,,,a few over from "Original Holes"

c) Draw a Line from CENTER of Tooth's Point,,,,across the Sprocket to Center of Opposite Tooth.
That makes a Centerline Refference Point.

d) move over to next tooth and do same thing.
That makes an X on cam sprocket,,,centered on the pair of teeth

e) Mark a 3rd Line from BETWEEN the teeth as close as you realistically can.

All the lines SEEM unecessary,,and probably ARE.
But it makes it Much easier to SEE 1/2 way point between the teeth.

And the Middle Line compared to either "outer line" is the 1/4 Tooth point.

It's easy to Eyeball 1/2 tooth Point,,close enough,
But Lots trickier than it sounds to just Eyeball 1/4 or 3/8 Tooth points without some refference lines.

Or,,You can use a Protractor,,,or Degree Wheel,,,or however ya want to.


Important Ting is to Redrill the new pair of Cam Bolt Holes just a little Less than 1/2 Tooth from Original.

Ok,,,Stock Cam Timing Set Up is like this:
The 2 Cam bolts are Horizontal across head,,left and right,dead level,,,and Timing Mark is Straight Up.

Bolts at 3:00 and 9:00 and MARK is at High Noon.

Make Your New Holes at 2:00 and 8:00 so they do interfere with Originl Holes.

Do same for any additional pairs of Holes you may want to use,,,,,or if ya screw up somehow and need to "start over".

REGARDLESS where ya Put the Holes,,,,
You need to also add a New Timing Mark.
Align the New Holes Horizontally by Turning the Sprocket.
So the holes are at 3:00 and 9:00.
And make your New/Extra timing MARK at 12 Noon.

Keep in mind that our NEW HOLES Do NOT lign up with Sprockt Teeth the same as Stock.

The Installation Timing Procedure is SAME as Normal.
New Bolt Holes Horizontal,,w/ New MARK Straight Up.

What has Changed it the Relationship of the TEETH to the Bolt Holes.

Sometimes that takes a minute to sink in,,,even for me.
I find myself "counting on my fingers",,LOL
Counting WHAT,,,I have no clue?
Just regaining a mental grip on the Orientation of the shuffled around factors.

All sorts of ways to re-index the cam,,,it's NOT as complicated as it may sound.

On Your particular Cam Drive set-up,,,I think easiest way is to simply redrill the Holes ,,offset a little less than 1/2 tooth.

CAM DIRECTION:
To Increase Hi RPM Power--RETARD the CAM
To Increase Low RPM Power-ADVANCE the Cam.

Looking at engine/cam from Right Hand Side,,the engine & cam turn COUNTER~CLOCKWISE.

>Retarding the Cam for Hi RPM requires going in Opposite Direction.
So Cam ends up about 1/2 Tooth CLOCKWISE from "Normal"

>Advancing Cam for Low RPM power requires moving cam Counter-Clockwise by 1/2 tooth(MAX)

All the Timing marks stay "Normal",,,but the Bolt Pattern is Moved.
When Cam is Turned to line up with Altered Bolt Pattern,,,then You Got it.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
You go figure for yourself how to make Ignition Timing ADJUSTABLE,,,if it Isn't already adjustable.

It needs a SLIGHT advance to make better power,,even with a Stock Engine.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
You NEED also to Raise Compression a LITTLE.

Best way is obviously to install a Hi-Perf Piston.

Or,,,if Ya just WANT TO Do it Yourself,,,
You can Mill the Head or Deck the top of Cylinder,,or Lathe Turn some off Bottom of Cyl.

I prefer to START at Top of Cylinder.
Because that effectively Raises Piston to Top of Deck or Higher.
All that is "Dead Area" Volume which does not contribute to combustion.
And it gives Biggest Volume REDUCTION per-depth-of-cut.

Meaning,,,.020 " Off Cylinder raises Compression More than same amount milled from head.

Your Compression ratio is like 9.2:1 with a 195cc actual engine size.
That's about 22.5 cc Chamber Volume

21.cc = about 10.2 CR
20cc=10.7 Cr

So approx 1.5 CC reduction in Chamber Volume = a 1 full point of CR increase.

Ya got a 65.5mm Cyl Bore,,
So, a .020" Milling on Cyl removes 2CC's of Volume

That's 1cc Reduction per .010"
.015" = 1.5CC
1.5cc would give you a strong but Liveable 10:1~10.25:1 Cr

You CAN HAND LAP .010~.015 off to of Cylinder.
It's a pain in the behind on a Honda Motor,,,but not too bad.
Just swirl Cyl Deck on someFRESH 180 Grit wet/dry paper laid on a Flat Surface.
Keep Rotating it so it gets cut evenly.
IT's TRICKY because the CAM TOWER are is SOFT and cuts Quick,,,while Cyl Sleeve is relatively HARD and cuts Slower.

Makes it tuff to take down Evenly .
But it's Do-able with extra care and attention,, and Patience.

Way easier to have a Machine Shop cut it.

Milling the Head or Cyl WILL add about 2* of CAM TIMING RETARD.
Ya GOTTA PLAN Ahead and account for That in your Cam Grinding experiment.
For Example,,If ya "Fudge" the Cam Holes and go a Full 1/2 Tooth or further,,that's Over 12*.

Add 2* More from the Head/Cyl Shaving,,,that 14* or More TOTAL.
That's just Asking for Less-Than Desirable results.14 is Too much.

So targetting 1/4 Tooth Cam Change,,WITH the Head/Cyl milling keeps You on Good Side of 10~12* Max cam timing change.

If Ya know how to do a Top End job,,replace Piston/rings,etc...
You can Do it all in a day easy.
Grind the Cam
Re-Drill Sprocket
Sand off a little from Top of Cyl(argh!--it's Work)
And do whatever Ignition timing may need to make it adjustable---usually just slotting the mounting holes for stator or pick-up/trigger coil.

Your XL's HP PEAKS at 8,000
Torque Peak is Lower than that.
It will Rev as-is to near 10,000 but is WAY outa breath up there= WEAK,Low Power.

The Above Mods will Raise Efficiency a LITTLE,,
but more importantly if Shifts Power Peak up the RPM band.

Where it quits pulling Now at 8000,,,
It should pull HARDER all the way to mid 9,000's.

The way Engine's Power Declines after it Peaks,,,and falls off RAPIDLY,,,

With a little beginner's luck you could have as much as TWICE the Power at 9000~9500 rpm as You do now.

And it will pull MUCH HARDER to that RPM,,,instead of piddle-farting around after 7,000 like it does now.

It will run LOWER Gearing Better,,,because it wont fall on it's face so early as it winds out

It'll run HIGHER Gearing Better,,LOTS Better,,,up at "top speed" because of the Higher RPM Peak "RETURNING " the "Lost Power" from after the Stock Engine's Peak.
AND adding some Extra Power

With Increased Compression and Advanced Ignition Timing,,,there'll be Very Little LOST low end power.
Compression is Freakin' MAGIC for boosting Low Speed power.

You could just as easily get a Net GAIN in Low Speed Torque.

......................................................................
All You're Doing is :
Making that "ROUND BOTTOM EGG" Shaped Cam Lobe,,
into a "Flatter Bottomed Egg Shape" by Just 10~15 Thousandths of an inch.

Drilling a couple small holes in a Thin,Soft ,Cast Iron Sprocket,,,about 1/2 tooth Off-Center from Original ones.

MAYBE slotting the Ignition mounting holes

And grinding .010~.015" off top of Cylinder.

....................
Use Mobil 1 in it,,,also good as assembly Lube

Set Valve Clearances anywhere within .002" to .004" range.
Because You Re-Textured the Cam and Lifter Surfaces,,,
You Should EXPECT a small initial wear-in,,,which will need an early Valve Adjustment.
That will stabilize Very Quickly

JETTING,,You MAY need to go up a Jet size or 2

Do whatever ya wanna do for Carb or Exhaust.
Dont really NEED a bigger carb,,,
A Good Pipe helps,,,but aint totally necessary to get most of the benefits possible from your mods


NOW do ya see why Folks are Reluctant to "spell it all out"??
Takes Longer to Tell than to Do.

Try it and see how ya do,,,and if there's a #1 it is DO NOT GET CARRIED AWAY and OVER DO IT.

These are ALL SMALL Specs which make BIG Differences.
It's Very Easy to go too far.

If You Stay Conservative and Realistic,,,that will tolerate a Screw-Up and still give Good Results.

But if ya get overzealous and Deliberatly target MAX,,,The Edge,,,,,thats VERY UNFORGIVING and offers about the ONLY gaurantee in all this.
A TINY miss at the extreme edge Gaurantees You Wont be happy with the results.

Try it,,,get a feel for it,
And Later you can get CHEAP Used Cams to experiment with.

And honestly,,,You NEED COMPRESSION.
If You gotta take engine apart to do "machine work",,
It's Really WAY better for Lottsa reasons to spend the $$ and just stick a New Hi-Perf/Hi-Compression piston in it.

Even though there IS a certain satisfaction in doing it all yourself,from scratch.

So Think Ahead,,,about whether ya wanna fooll with the motor to see what YOU can get outa it,,,or whether ya just wanna get it together with a bit more power,,,,then just Ride .

If it's Hi Mileage or "tired",,ya may need a new piston Anyway.

Good Luck,,,,
if You Do try it,,let us know how ya like the results.
Take your time,,go carefully,,,and You'll probly surprise the Heck outa yourself.

Answer 2

Camshaft Grinding

Answer 3

No it will not work. The D15B7 was available 92-95 btw, not only 93-95. The D15B8 has 8 valves and the D15B7 has 16 valves. It probably would fit, however the D15B8 cam in the D15B7 would only allow half the valves to open. Also the B8 has bigger lobes. Second of all, why the hell would you want to bother getting an economy cam and putting in another engine thats already economic? The B8 cam is worse than the B7 cam. So NO, the cam will not work on the B7.

Answer 4

it takes a special machine to do the job and after grinding the camshaft depending on how much material was ground off it has to be re-hardened or it will not hold up and fail inside the motor it is not worth the hassle or problems that can occur

Answer 5

Forget changing the cam, it will only move your power band up in the RPM range.

What would be better is a piston kit from Thumper Racing.

This will give more power from idle to high rpm.

Answer 6

definitely not advisable, any heat you add to the camshaft will actually weaken the metal only allowing it to wear at a higher rate. just stick to stock. there are plenty of other things that you can do to increase power output.....

Answer 7

Grind off the base circle not the lobe.

Answer 8

do not do that. buy a new stick,springs and new rockers with a better ratio,if you want go ahead and gring the cam down,it's your car,time and money

Answer 9

take it to a engineering workshop