JDogg

we dont have e85 around here

Aquafina

iTrader: (3)

Rockets angst and jealousy of my youthfulness has finally come out.

spun Vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Don Lackey &raquo;</TD></TR><TR><TD CLASS="quote">Yeah.

The cam gear is 100mm in dia. The circumfrence is ~314mm (100mm x PI). So 1mm is about 1.1 cam gear degree (2 crank degrees).

Meaning when the head is milled 1mm (creating 1mm of t-belt slack) the cam gears need to rotate 1.1 degrees to take up the 1mm slack.


Modified by Don Lackey at 11:46 PM 2/23/2007</TD></TR></TABLE>

Im a little lost.

A d-series cam gear dia is 114.3mm circumfrence is 358.7mm If (114.3mm x PI) what is PI


Modified by spun Vtec at 1:16 PM 3/2/2007

Natural Aspirations

pi = 3.14159265

Natural Aspirations

Simple answer to what you are trying to figure out. Your cam gear has about 360 mm of circumference and turns 360 deg. For every 1mm you mill the head it adds 1mm of slack to the belt on each side retarding your cam 1 deg for every 1mm milled.

This is a rough estimate and should not be used for a final number, it should be used to get you close.

bluedlude

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Im a little lost.

A d-series cam gear dia is 139.7mm circumfrence is 358.7mm If (139.7mm x PI) what is PI</TD></TR></TABLE>


someone hasnt taken algebra tisk, tisk

spun Vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Natural Aspirations &raquo;</TD></TR><TR><TD CLASS="quote">Simple answer to what you are trying to figure out. Your cam gear has about 360 mm of circumference and turns 360 deg. For every 1mm you mill the head it adds 1mm of slack to the belt on each side retarding your cam 1 deg for every 1mm milled.

This is a rough estimate and should not be used for a final number, it should be used to get you close.</TD></TR></TABLE>

so If a d16 head is milled 0.020 in or .508mm, that means that .5 degree of advance should get you back around stock?

for instance my head is milled .020in and my block is decked .020in = a total of .040in so .040 in or 1.016mm 1 degree of advance will put you aprox back to stock.

CHEETAH

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by spun Vtec &raquo;</TD></TR><TR><TD CLASS="quote">

for instance my head is milled .020in and my block is decked .020in = a total of .040in so .040 in or 1.016mm 1 degree of advance will put you aprox back to stock.</TD></TR></TABLE>

at the crank (not the cam gear) ... typical aftermarket camgear index marks are 2 cam degrees for every 1 crank degree. Lets say with a skunk2 gear then its 1/2 of 1 mark on the camgear (assuming each mark is 2 degrees at the crankshaft)

00Red_SiR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CHEETAH &raquo;</TD></TR><TR><TD CLASS="quote">

at the crank (not the cam gear) ... typical aftermarket camgear index marks are 2 cam degrees for every 1 crank degree. Lets say with a skunk2 gear then its 1/2 of 1 mark on the camgear (assuming each mark is 2 degrees at the crankshaft)

</TD></TR></TABLE>

Just a clarification question, did you mean to say that 2 crank degrees normally equals 1 cam degree? (instead of saying 2 cam degrees equals 1 crank degree)

CHEETAH

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00Red_SiR &raquo;</TD></TR><TR><TD CLASS="quote">

Just a clarification question, did you mean to say that 2 crank degrees normally equals 1 cam degree? (instead of saying 2 cam degrees equals 1 crank degree)</TD></TR></TABLE>

yes I did ... thanks

vietCRIPPIN916

Rocket

I might do a cool degree write-up. But you guys have to promise to buy all RLZ/Donf/RM stuff and sign a "grasshopper" agreement that you will forever hold RLZ/Donf/RM as your superiors.

base-op.1320

It seems like to me everyone has talked about lining up your cams to your pistons to achieve maximum compression but nobody has talked about changing the lobe seperation or valve overlap. I thought on a turbo car you can gain alot of power by adjusting your lobe seperation especially cause the air is being forced in. I would believe on an all motor setup you could change your powerband quite a bit by changing you lobe seperation. This is something a dual cam has over a single cam setup where your lobe seperation is ground into the cam.

JDogg

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Don Lackey &raquo;</TD></TR><TR><TD CLASS="quote">I might do a cool degree write-up. But you guys have to promise to buy all RLZ/Donf/RM stuff and sign a "grasshopper" agreement that you will forever hold RLZ/Donf/RM as your superiors.</TD></TR></TABLE>

ill give you 5bux if you add my name to the list of superiors

bluedlude

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by base-op.1320 &raquo;</TD></TR><TR><TD CLASS="quote">It seems like to me everyone has talked about lining up your cams to your pistons to achieve maximum compression but nobody has talked about changing the lobe seperation or valve overlap. I thought on a turbo car you can gain alot of power by adjusting your lobe seperation especially cause the air is being forced in. I would believe on an all motor setup you could change your powerband quite a bit by changing you lobe seperation. This is something a dual cam has over a single cam setup where your lobe seperation is ground into the cam.</TD></TR></TABLE>

isnt that where you actually use you cam gears? degreeing it gets it to zero and then tuning the cam gear from there would be tuning the overlap right, correct me so i can understand?

mgags7

^^correct

everyone is just talking about setting the cams to exactly zero degrees, after that you can adjust the overlap.

I'll say in my personal experience, adding overlap moves the powerband down. At zero degrees, my car made about 5hp more up top, but at +2/-1 it made about 3-5lbs more torque over all of 4-6k rpm.

Aquafina

iTrader: (3)

OBX &gt; all

96Spec Ek

Do I have to lock the engine in vtec while degreeing my cams? It just doesn't really make sense to me to do this off of the primary lobes. If this has been covered flame on

alterdcreations

yes

bluedlude

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 96Spec Ek &raquo;</TD></TR><TR><TD CLASS="quote">Do I have to lock the engine in vtec while degreeing my cams? It just doesn't really make sense to me to do this off of the primary lobes. If this has been covered flame on </TD></TR></TABLE>

that was a good question. i never would have thought to ask until i was doing it probably .

CHEETAH

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 96Spec Ek &raquo;</TD></TR><TR><TD CLASS="quote">Do I have to lock the engine in vtec while degreeing my cams? It just doesn't really make sense to me to do this off of the primary lobes. If this has been covered flame on </TD></TR></TABLE>

yes, just swap the rockers pins and it will lock one valve on intake and one valve on exh .... this will only work for degreeing camshafts but not for checking clicking clearance.

spun Vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CHEETAH &raquo;</TD></TR><TR><TD CLASS="quote">

at the crank (not the cam gear) ... typical aftermarket camgear index marks are 2 cam degrees for every 1 crank degree. Lets say with a skunk2 gear then its 1/2 of 1 mark on the camgear (assuming each mark is 2 degrees at the crankshaft)

</TD></TR></TABLE> so this would be correct

for instance my head is milled .020in and my block is decked .020in = a total of .040in so .040 in or 1.016mm 1 degree of crank advance or 2 degrees advance @ the cam gear will put you aprox back to stock.


^^^
That is not correct




Modified by spun Vtec at 3:46 PM 3/4/2007

00Red_SiR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by spun Vtec &raquo;</TD></TR><TR><TD CLASS="quote"> so this would be correct

for instance my head is milled .020in and my block is decked .020in = a total of .040in so .040 in or 1.016mm 1 degree of crank advance or 2 degrees advance @ the cam gear will put you aprox back to stock.
</TD></TR></TABLE>

It means that with a total of .040" removed, it will require 2 degrees (crank) advanced or about 1.1 cam degrees advanced to correct for it. Remember your cam turns 1/2 as many times as your crank so whatever the crank correction is, the cam correction would equal roughly half of that.

spun Vtec

I was mixed up because cheetah had it backwords. Ok so your saying .040 milled = 1.1 degree at the camgear and 2.2 degree advance at the crank.


Modified by spun Vtec at 1:28 AM 3/24/2007

00Red_SiR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00Red_SiR &raquo;</TD></TR><TR><TD CLASS="quote">

It means that with a total of .040" removed, it will require 2 degrees (crank) advanced or about 1.1 cam degrees advanced to correct for it. Remember your cam turns 1/2 as many times as your crank so whatever the crank correction is, the cam correction would equal roughly half of that. </TD></TR></TABLE>