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bc 288 cams degreeing

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kinda-stock

Proven Member
55
0
Jun 4, 2016
jefferson, Louisiana
so i have read all the forums. watched all of boosted beaver and jafro videos. purchased all of the cam degree tools and made the zero lash lifters...ect. All of this is on a 6bolt aluminum rod engine. Manley pistons. 1mm oversize valves on intake and exhaust. head has been resurfaced.

when installing these cams zero'd in, i notice the OBX cam gears are a half a tooth of. in order to bring the cams into spec from the cam card sheet, i had to retard the intake 5 degrees. now with the cam, nothing is measuring out to the cam card.

has anyone had experience with degreeing bc288 cams? the exhaust cam duration and centerline doesnt match the manufacture specs. maybe i'm wrong but no matter what i do i cant come up with correct exhaust cam numbers in retrospect to the cam card. any help is greatly appreciated.
 
Use the centerline method instead of trying to get the opening and closing perfect. If the indicator isn't perfectly parallel to the valve stem it'll be off, not to mention most of the time cam specs vary from the card.
 
thats just it. when i measure max lift and rotate .050 forwards and backwards...my centerline number is no where close to the cam card.
 
thats just it. when i measure max lift and rotate .050 forwards and backwards...my centerline number is no where close to the cam card.
 
i understand adjustable cam gears can make up the difference and are a must to zero in cams to their manufacturer specks.

i used the J Racing timing belt install kit and the exhaust cam lines up a half tooth off. I have been fighting with this for a month. engine is out of the car and everything is torqued down. This exhaust cam specks arent close to what the cam card specifies and the duration is way off aswell
 
i zero'd my gauge. turned till i had .050 lift. recoreded that number as my exhaust opening event. then turned till max lift. recorded that numberas my centerline. zero'd the gauge again then kept turning till .050 again for my closing event.

and still numbers dont add up. here is the camcard

really dont see how they are getting the exhaust closing event at 0 degrees
 

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According to that card setup the intake to a 102* centerline and the exhaust to a 110* centerline.

But, with all big cams i end up taking out overlap with the gears to get a good idle.
 
i used the calculator and herw are my numbers from the exhaust cam. E.Open 40 BBDC. E.Close 292 BTDC. that equates to a centerline 256 BTDC.

anyway i slice this my max lift is my max lift and .050 later supposed to be my closing event. with these calculations my exhaust duration is 510 degrees? honestly guys i know this doesnt sound correct. anyone else have any ideas around this?
 
Take a picture of your intake opening, intake closing, exhaust opening, and exhaust closing events @.050". Capture the degree wheel and pointer in the pic. Did you set the pointer on the degree wheel with a piston stop?
 
called BC and had me strait in 15min. to make things simple. turn till .050 = opening event. then keep turning till .050 again = closing event. my points are:

I.O. 8°
I.C. 32°

E.O. 38°
E.C. 2°

The helpful calculator link from above with these numbers give me a LSA of 105° and an overlap of 10°.

i was told that the cam card gives me a happy medium of power placement. question. turbo on this 2.0 2g AWD 8.8 rear end aluminum rod motor 5speed Talon is a gt35r. I understand 288's are big cams. where can i expect the power to come in at with the LSA at 105°? car will be a weekend warrior street car.
 
called BC and had me strait in 15min. to make things simple. turn till .050 = opening event. then keep turning till .050 again = closing event. my points are:

I.O. 8°
I.C. 32°

E.O. 38°
E.C. 2°

The helpful calculator link from above with these numbers give me a LSA of 105° and an overlap of 10°.

i was told that the cam card gives me a happy medium of power placement. question. turbo on this 2.0 2g AWD 8.8 rear end aluminum rod motor 5speed Talon is a gt35r. I understand 288's are big cams. where can i expect the power to come in at with the LSA at 105°? car will be a weekend warrior street car.
 
Is the car auto or manual?

Those aren't huge cams, kelford 272's and gsx s2's have more duration. They are a large cam for a street car. But for a race car that doesn't have to idle well, or pull much vacuum they are fine.

How else were you getting your valve events?
 
trying to follow youtube and internet forums completely overcomplicated degreeing cams. the car is a 5speed with twin disc clutch and shep stage 4 trans.

honestly i want the SBC lope. i want this car to be overly obnoxious. i know 4cyl wont have 500 ft.lbs of torque at 1500rpms and midrange i am not too concerned about.

will these numbers put the power at 5500 and on? or do i need to move the LSA tighter?
 
It will lope with that overlap. The intake and turbo will have a huge impact on top end power.


With a 35r turbo in a .82 housing, forrester intake, and cams with 226* duration I was able to make peak power at 8800rpms. Taking overlap out of the cams actually led to the highest rpm peak power in my setup.


Almost any setup with a stock intake won't make peak power much after 7,000 rpms. There are exceptions like huge turbos and cams but for the most part they fall off after 7500 with the stock intake.
 
my turbo is an original "from 2005" garret GT35R with 82AR and zero miles on it. life gets in the way of car projects. this is my intake manifold. I know currently this stock throttle body may hinder performance but thats an easy upgrade.
 

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Any smim is going to work better than the stock intake over 7,000 rpms. The better ones just mitigate the losses under that range.

I'm running a 3586htz forced performance turbo, but at the boost range I did my testing a regular cast wheel 3582 should perform similarly.
 
i know my old 35R technology doesnt like shaft speeds after 28psi of boost. plan on keeping it around 20 - 25psi. How much power did you make with your 3586? Just excited that i can finally see the light at the end of the tunnel with this project
 
question. at what level of overlap have you guys seen the lopy cam sound go away? i want this car to pull hard to 8500+ rpms but i also want the tap happy cam sound.
 
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