cam advance,blown,stroked

Posted By: royt440

cam advance,blown,stroked - 06/20/09 09:26 PM

CompCams XE268H-10 The following is from the spec card.
I'm using 1.6 rockers: Intake .509, Exhaust .512
Duration @.006 I=268 E=280
Open @.006 I=28*BTDC E=74*BBDC
Close@.006 I=60*ABDC E=26*ATDC
These specs are for cam installed @106* Intake Centerline
Duration @.050 I=224 E=230
Lobe Separation 110*

Quote from CompCams instructions "We grind most all of our cams 4* advanced."

So does that mean if I install it straight up (dot to 0* mark on crank gear) that I already have 4*? Do I need any more? The crank gear has settings for 0,2,4,6,&8* advance or retard.

The block is a 440, .060over with the 500ci kit from 440Source.
Stealth heads.
Ross dished pistons. About 8:1 compression.
Dyer's 671 blower, pulleys at 8lbs.

Thanks,
Roy

Posted By: RodStRace

Re: cam advance,blown,stroked - 06/20/09 09:35 PM

Roy, I'd strongly suggest that you spend the money and time to get the stuff and degree in the cam properly, not just line up the dots.
On a stock rebuild you can get away with that sort of thing, but on a HP build like you have outlined, checking things is a BIG part of the process to make sure it will live and perform up to it's potential.

http://www.google.com/search?hl=en&q=how+to+degree+in+a+camshaft&aq=f&oq=&aqi=g1

Posted By: blownzoom440

Re: cam advance,blown,stroked - 06/20/09 10:53 PM

the cam is small for the cubes but should be fun.

Posted By: RapidRobert

Re: cam advance,blown,stroked - 06/21/09 03:37 AM

Quote:

Quote from CompCams instructions "We grind most all of our cams 4* advanced."
So does that mean if I install it straight up (dot to 0* mark on crank gear) that I already have 4*?

I'm interested also

Posted By: DaytonaTurbo

Re: cam advance,blown,stroked - 06/21/09 03:47 AM

Quote:

the cam is small for the cubes but should be fun.

With a 6-71 on top that cam is tiny for the cubes. You're going to have so much bottom end with that cam you may want to retard it a few degrees for upper rpm help.

Posted By: goldmember

Re: cam advance,blown,stroked - 06/21/09 05:10 AM

Yes it's ground with 4 degrees advance built in,you need to install it straight up and check the ICL,it should be 106ICL. That doesn't mean it will work the best at that point,but you should still confirm that your within 2 degrees of that point or make corrections to get it there.

Posted By: R70RUNNER

Re: cam advance,blown,stroked - 06/21/09 06:07 AM

Sounds like a pretty mild build really, effective CR of about 10:1 maybe? Lots left on the table using a relatively small 6-71 on that much motor... Degree the cam in so YOU know what's going on and run it!

Posted By: royt440

Re: cam advance,blown,stroked - 06/21/09 11:25 AM

Again, Moparts members, thanks for the responses.

It is going to be primarily a street car and I've always wanted a blower. There are quite a few nice 3rd gen Chargers in the Member's Photos.

I already have a dial indicator and found some nine inch degree wheels on both Summitt and Jegs that aren't too expensive (for one job). I've printed the procedure from the links above and plan on giving it a shot.

I had called the tech line for CompCams but must have called on their busiest day.

Maybe I'll try one more time.

Roy

Posted By: blownzoom440

Re: cam advance,blown,stroked - 06/21/09 11:40 AM

i know it is time consuming to check everything but you will relax knowing things are OK and where you can go from there.i have a .549/.559 113lsa,252/260* at .050 cam i ran for about 50 passes if you want to change.[solid lifter]cam only.40$ plus shipping.i went to a roller is why i changed it.
what pulleys do you have?3%UD or 1/1?

Posted By: moper

Re: cam advance,blown,stroked - 06/21/09 01:41 PM

Even with the small blower, I'd strongly advise checking with some cam guys about a real blower type cam. I dont think that one is what you want. I'm not the best with forced induction... but I think you may be better off with much more lift, at least 20� at .050, and an LSA around 114. And I wouldnt advance it...

Posted By: Dodgem

Re: cam advance,blown,stroked - 06/21/09 02:01 PM

Posted By: Dodgem

Re: cam advance,blown,stroked - 06/21/09 02:04 PM

I have a nice roller for sale 114 lobe separation 268/270 @ .050 and .424 (lobe) lift =(.678 with 1.6)

Posted By: blownzoom440

Re: cam advance,blown,stroked - 06/21/09 02:15 PM

Quote:

I have a nice roller for sale 114 lobe separation 268/270 @ .050 and .424 lift =(.678 with 1.6)

not too streetable with the spring psi and the $$ of it.

Posted By: R70RUNNER

Re: cam advance,blown,stroked - 06/21/09 03:16 PM

FWIW, one of the blower companies is now spec'ing 110lsa cams for street blowers, shorter duration with higher lift.Not sure if this is what the OP is using as a guide???

IMHO, the OP would be better off with a 114lsa, What he has will work, but he'll just lose some boost out the pipes.

I'd call Engle Cams and see what they have to say

...

Now if I can just get people to stop buying the blower(s) off my project motor it might get done too

Keep us updated Roy

Posted By: Dodgem

Re: cam advance,blown,stroked - 06/21/09 04:30 PM

Quote:

Quote:

I have a nice roller for sale 114 lobe separation 268/270 @ .050 and .424 lift =(.678 with 1.6)

not too streetable with the spring psi and the $$ of it.

streetable is a wide perception! LOL!!!
I know it's mild but he said he want's mild!

Posted By: blownzoom440

Re: cam advance,blown,stroked - 06/21/09 07:52 PM

Quote:

FWIW,What he has will work, but he'll just lose some boost out the pipes.

i dont think he will loose any out the pipes as it has 7* overlap.i ran it in my dynosim program for the cam profile.

Posted By: goldmember

Re: cam advance,blown,stroked - 06/21/09 08:05 PM

Where did you come up with 7 degrees of overlap? Are you using .050 numbers? Overlap at .050 is not usefull.It's 54 degrees and thats IF you accept the advertized duration,which is adjusted by the marketing department.

Posted By: blownzoom440

Re: cam advance,blown,stroked - 06/21/09 08:19 PM

yes it was the .050 and at about.100 lift max.some have had 0 overlap and ran ok.my opinion he has a small amount.mine has 40* at .050.i have had as much as 70* at .050.

Posted By: Mr.Yuck

Re: cam advance,blown,stroked - 06/22/09 01:04 PM

I'd probably get a cam designed for boost. They tend to line a 112-114 centerline.

Posted By: Mr.Yuck

Re: cam advance,blown,stroked - 06/22/09 01:08 PM

Quote:

I have a nice roller for sale 114 lobe separation 268/270 @ .050 and .424 lift =(.678 with 1.6)

how's a .424 lift cam got to 678 w/ 1.6's???? my math says it would bump to .452????

Posted By: Dodgem

Re: cam advance,blown,stroked - 06/22/09 05:51 PM

Your math is really bad man
lobe lift x rocker ratio
.424 X 1.5 = .636
.424 X 1.6 = .6784

Posted By: patrick

Re: cam advance,blown,stroked - 06/22/09 08:05 PM

Quote:

CompCams XE268H-10 The following is from the spec card.
I'm using 1.6 rockers: Intake .509, Exhaust .512
Duration @.006 I=268 E=280
Open @.006 I=28*BTDC E=74*BBDC
[Email]Close@.006[/Email] I=60*ABDC E=26*ATDC
These specs are for cam installed @106* Intake Centerline
Duration @.050 I=224 E=230
Lobe Separation 110*

Quote from CompCams instructions "We grind most all of our cams 4* advanced."

So does that mean if I install it straight up (dot to 0* mark on crank gear) that I already have 4*? Do I need any more? The crank gear has settings for 0,2,4,6,&8* advance or retard.

The block is a 440, .060over with the 500ci kit from 440Source.
Stealth heads.
Ross dished pistons. About 8:1 compression.
Dyer's 671 blower, pulleys at 8lbs.

Thanks,
Roy

yes, if you line up the dots, it *should* be 106 ICL

Posted By: Mr.Yuck

Re: cam advance,blown,stroked - 06/23/09 12:21 PM

Quote:

Your math is really bad man
lobe lift x rocker ratio
.424 X 1.5 = .636
.424 X 1.6 = .6784

really you take .424 DIVIDE by 1.5 = 282.66

then you multiply 282.66 x 1.6 = you new lift 452.26
He doesn't have a 636 cam to start with. That's not how it works.

Posted By: RapidRobert

Re: cam advance,blown,stroked - 06/23/09 01:23 PM

easiest way is to multiply your(1.5) lift figure by 1.067 to get the new 1.6 lift amount. Got a Q, if the cam card says 110 ICL & they automatically grind their cam 4 deg advanced does that mean that when you degree the cam that the ICL will come in @ 106? And ICL is different from the 110 LCA angle on the card?

Posted By: goldmember

Re: cam advance,blown,stroked - 06/23/09 04:16 PM

ICL=intake centerline. LSA=lobe seperation. 106ICL with a cam ground on a 110LSA is 4 degrees advanced.110ICL would be straight up,114ICL is 4 degrees retarded,ETC. The above confusion is the numbers given are LOBE lift,not gross lift.

Posted By: RapidRobert

Re: cam advance,blown,stroked - 06/23/09 07:46 PM

Quote:

ICL=intake centerline. LSA=lobe seperation. 106ICL with a cam ground on a 110LSA is 4 degrees advanced.110ICL would be straight up,114ICL is 4 degrees retarded,ETC.

Now I understand. Thank you

Posted By: royt440

Re: cam advance,blown,stroked - 06/23/09 09:06 PM

Thanks for all the input.

I decided to go Straight up since the cam already had 4* built in. I'll degree it after I get the pistons in.

Also, thanks for the offers on some wilder cams. It will be a while before I fire this one but I'll post results then on how it runs with this 268.

I think it was the BDS website that recommended 110* lobe separation on supercharged engines running on gasoline. I didn't get a CompCams recommendation, just went by the cam descriptions and I don't think they had one specifically for blower's when I bought this a few years ago. Plus, some sites said the blower would make up for not using an aggresive cam and allow for easier tuning and starts.

Everybody keep it safe and thanks again.
Roy

Posted By: blownzoom440

Re: cam advance,blown,stroked - 06/23/09 10:32 PM

it will be interesting to see your cranking psi.
the first cam i tried was a BDS with 110 and 90* overlap.

i had 110 psi with 8.8cr

Posted By: patrick

Re: cam advance,blown,stroked - 06/24/09 01:59 AM

Quote:

Quote:

Your math is really bad man
lobe lift x rocker ratio
.424 X 1.5 = .636
.424 X 1.6 = .6784

really you take .424 DIVIDE by 1.5 = 282.66

then you multiply 282.66 x 1.6 = you new lift 452.26
He doesn't have a 636 cam to start with. That's not how it works.

uh, he said it was .424" LOBE lift

Posted By: R70RUNNER

Re: cam advance,blown,stroked - 06/24/09 04:33 AM

Quote:

it will be interesting to see your cranking psi.
the first cam i tried was a BDS with 110 and 90* overlap. i had 110 psi with 8.8cr

them are the ones....

Posted By: Mr.Yuck

Re: cam advance,blown,stroked - 06/24/09 11:21 AM

Quote:

Quote:

Quote:

Your math is really bad man
lobe lift x rocker ratio
.424 X 1.5 = .636
.424 X 1.6 = .6784

really you take .424 DIVIDE by 1.5 = 282.66

then you multiply 282.66 x 1.6 = you new lift 452.26
He doesn't have a 636 cam to start with. That's not how it works.

uh, he said it was .424" LOBE lift

got ya!

Posted By: Dodgem

Re: cam advance,blown,stroked - 06/25/09 12:24 AM

uh, he said it was .424" LOBE lift

got ya!

Actually I edited it to Lobe lift when I seen you thought a big roller could be that small of lift.
I just assumed when I said .424 lift with 1.6 was .678 You would have know i was talking lobe lift! LOL!