Rebelord

iTrader: (2)

224/240 .636/.609 109+4
LSK/XE-R lobes
Intake Valve opens - IVO 31.5 7 -30.5
Intake Valve closes - IVC 61.5 37 -0.5
Exhaust Valve Opens - EVO 77.5 53 13.5
Exhaust Valve Closes - EVC 31.5 7 -32.5
Exhaust Centerline - ECL 113 113 113
Overlap 63 14 -63

DCR: 8.47

For a stock headed LS1 with LS6 intake and full bolt ons.

Am I nuts or good to go??

Ski

brad8266

iTrader: (23)

sounds kinda overkill to me, im by no means a cam expert though. No way id run stock heads with it, that for sure.

SStrokerAce

iTrader: (2)

Nuts



One reason why some people never give advice on here about cams is that just designing your own cam to arbitrary specs and then posting them up without any real information on what you want the car to do or what the car has on it is

Good Luck,

Bret

brad8266

iTrader: (23)

pianoprodigy

iTrader: (1)

Why don't we tell him what's wrong with that cam rather than practically telling him he's an idiot?

The first problem I see is that the IVC is 37. From what I've read, that's way too low and will peak very low. Also, I don't see any reason to have a 16 degree split on stock LS1 heads. There's a reason most every cam out there is a positive 2-6 degree split.

What are you trying to accomplish with your cam swap? I assume you have an auto which will influence your cam choice. What stall?

brad8266

iTrader: (23)

I didnt give any real advice because like i said, im not a cam guru, although i know some stuff.

pianoprodigy

iTrader: (1)

Understood. I'm no guru by any means, but I like to try to help. I can at least get him started by asking some questions.

OhIt'sBeenBraughten

I don't understand why everyone wants to re-invent the wheel around here. There are plenty of proven cams that have been designed by some pretty knowledgeable folks.

Rebelord

iTrader: (2)

guys...here

by no means am i in no way trying to re-invent the wheel. Im trying to develop a cam to create the most cylinder pressure to create the most DCR to make torque. you make torque you make power. I am reading, learning as much as i can about cams, valve events and understanding how it all works together. so, if i can create a 8.47:1 dcr and have enough overlap to help the stock heads scavenge to suck in more fuel/air mixture to make more power. because the heads are low flow restricted and will have a hard time with the upper rpms to continue to create the power. thats why i included the lsk lobe on the intake. like i said i am still learnig. however, i believe if this cam can create excellet torque down low and hold the power up top. then it can be a good daily driver with some good weekend track abilities. look at the MS4 239/240 .643/609 111lsa(dont know the advance) creates a 7.47DCR to my calculations. (if im wrong, point me in the right direction) It creates good power, however i believe it can be used in a better situation with good flowing heads. well, thats all i have.

Ski

Patrick G

iTrader: (14)

That cam will actually work pretty well, but it's not ideal.

Here's what I like:
Big lobe area without too much duration on the intake side.
High DCR with stock heads.
Overlap biased to the intake side of TDC will allow the motor to pull past its hp peak (probably around 5800 rpm)
Narrow LSA gives nice valve events for area under the curve

What I don't like about it:
The exhaust split is a little too extreme for someone running LT headers with no cats. It has a little too much overlap if you were running cats.

A nice compromise of this cam would be:
224/232 .636/.595 109LSA +2
IVO 5
IVC 39
EVO 47
EVC 5
Overlap 10 (centered exactly over TDC)

N4cer

iTrader: (11)

Don't ya think an 8.47 DCR is less than optimal? I thought 8.5-8.8 is optimal.

Patrick G

iTrader: (14)

It is, but since this person is starting off with a 10.1:1 static compression ratio (stock heads), achieving a DCR above 8.5:1 is nearly impossible without a terribly early intake valve closing point. When you have over 11.0:1 SCR, hitting 8.5:1+ DCR is a lot easier!

ArrestMeRed99Z28

iTrader: (1)

I'm in the exact same boat with the fella that started this thread, want to make some good power with bolt ons and a cam with out spinning to the moon, this cam sounds great. What would the dynamic compression ratio of the 224/232 109+2 with stock heads&gaskets be? Can some one point me in the direction of a good calculator? Wish there was one like that gear calculator!
Thanks
AJ

LS1Formulation

iTrader: (13)

https://ls1tech.com/forums/generation-iii-internal-engine/630637-my-dcr-calculator-if-you-have-comp-grind-doesn-t-get-any-easier-than.html If you have a comp grind in mind, there you go!

Now, I keep studying more and more on my personal cam design and wonder if I could run a 226/230 XE-R lobe cam on a 107+2 LSA. On smaller cams I would think running a narrow LSA would be more beneficial to helping build torque down low. Can I hear some opinions as to whether or not this would be a possible design?

Hype

I made a thread asking about making DCR without higher SCR, and that answers my question haha. Thanks

Rebelord

iTrader: (2)

Patrick, now since im in the Marines and we finally have some time off, ive been drinking. but thank, you. i will respond when i get more sober. but finally im undertstanding how everthing works together. I will look at your exact specifacations further and see what your talking about. but however, what about i thought that 8.7DCR is better souted for higher flowing and better exhaust applications???

Ski

JPH

iTrader: (2)

what gear and converter combo is in this car?

cws T/A

iTrader: (3)

8.2 :1 67cc / .055 stock

8.5 :1 67cc / .040

Ragtop 99

iTrader: (7)

Where are you trying to make the power? Even with an early IVC, having a ton of overlap is going to result in poor low end power (e.g. 2000 - 2500 rpm), although the torque should build very rapidly.

eLTwerker

If IVO is 7* BTDC and EVC is 7* ATDC wouldn't the overlap be centered about TDC? This is where the overlap occurs, correct?