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Cam Help RB 496

Posted By: 47hudson

Cam Help RB 496 - 02/10/15 11:54 PM

Looking to change the camshaft in my engine. The engine is a 496" RB with approx. 12.5-1 comp. Indy 440-1 heads (mild porting and bowl blend) 1050 dominator running E-85. the current camshaft is an older Hughes grind:HEV5663BS with 1.6 rockers INT .626" EXH .642" duration @.050 int: 256 exh: 265 lobe sep: 108 The car is 3020lbs with me in it, 4500 dynamic converter, 727 trans, 471 gears, 33" tire. Foot brake the car. It currently runs 6.20s in the 1/8th has been 9.70s in the 1/4. I had been told by Hughes I could use a little more camshaft and was hoping to get some opinions of what I should be looking for from some of you who know more than me. Thanks

Attached picture 8425303-086.jpg
Posted By: gregsdart

Re: Cam Help RB 496 - 02/11/15 12:48 AM

Check out the mm305 grind in the comp cams catolog. You have the cubes to use that cam, and it has great .200 duration numbers. You will need 5500 to 6000 stall to make good use of it though.
Posted By: Cab_Burge

Re: Cam Help RB 496 - 02/11/15 02:49 AM

Quote:

Looking to change the camshaft in my engine. The engine is a 496" RB with approx. 12.5-1 comp. Indy 440-1 heads (mild porting and bowl blend) 1050 dominator running E-85. the current camshaft is an older Hughes grind:HEV5663BS with 1.6 rockers INT .626" EXH .642" duration @.050 int: 256 exh: 265 lobe sep: 108 The car is 3020lbs with me in it, 4500 dynamic converter, 727 trans, 471 gears, 33" tire. Foot brake the car. It currently runs 6.20s in the 1/8th has been 9.70s in the 1/4. I had been told by Hughes I could use a little more camshaft and was hoping to get some opinions of what I should be looking for from some of you who know more than me. Thanks

Dude, that is impressive, especially in that car I wonder how many racers that didn't know your car where wondering what is that car doing in this staging line the first time they saw it
Posted By: 47hudson

Re: Cam Help RB 496 - 02/11/15 04:39 PM

Dude, that is impressive, especially in that car I wonder how many racers that didn't know your car where wondering what is that car doing in this staging line the first time they saw it



Thanks, the car is a lot of fun. It does catch some people off guard, But Dad's car was Much more shocking to people because its more subtle than my car. When his car had the big engine in it and was running high 9's people would really do a double take.

Attached picture 8426034-Dad$10,000.jpg
Posted By: BradH

Re: Cam Help RB 496 - 02/11/15 05:44 PM

Quote:

... a 496" RB with approx. 12.5-1 comp. Indy 440-1 heads (mild porting and bowl blend) 1050 dominator running E-85. the current camshaft is an older Hughes grind:HEV5663BS with 1.6 rockers INT .626" EXH .642" duration @.050 int: 256 exh: 265 lobe sep: 108... I had been told by Hughes I could use a little more camshaft...


A little more cam? I'd say you're 15-20 degrees short of what that engine wants, depending upon the converter you mentioned.

The "If it was mine..." answer is, I'd try something around 272 at .050" intake, 276 exhaust & 110 LSA installed on 106 ICL. If you had a 5K+ converter, I'd go up around 4 degrees more on both lobes.

But since all my junk are stock-stroke 440s, it's just a s.w.a.g on my part.
Posted By: B G Racing

Re: Cam Help RB 496 - 02/11/15 06:50 PM

The engine combo would love a 650/650 lift-290/290-108 cl.solid flat tappet cam or 680/683-284/288-108cl roller cam.these are with 1.5 rockers,1.6 is even better.We used these cams in many builds.
Posted By: 47hudson

Re: Cam Help RB 496 - 02/11/15 09:32 PM

I have been looking at another Hughes cam or maybe Howards. Not really tied to any brand just want to get the most bang for the buck so to speak. What do you guys think about: Hughes: HUG STL6872BS3-8 3 BOLT .421"/.426" LOBE LIFT and 268/272 -108šLSA or Maybe a Howards:HRS-722412-08 Lift .639/.639 with 1.5 rockers 272 int./272 exh. I am running 1.6 rockers and don't want to go so big it ruins the combination.
Posted By: BradH

Re: Cam Help RB 496 - 02/11/15 09:47 PM

If you're looking for an off-the-shelf grind, the Hughes cam HERE is what I'd think is a reasonably good match.
Posted By: Dodgeguy101

Re: Cam Help RB 496 - 02/12/15 02:41 AM

Quote:

The engine combo would love a 650/650 lift-290/290-108 cl.solid flat tappet cam or 680/683-284/288-108cl roller cam.these are with 1.5 rockers,1.6 is even better.We used these cams in many builds.



If you want it right, listen to this man.
Posted By: Anonymous

Re: Cam Help RB 496 - 02/12/15 02:46 AM

Quote:

The engine combo would love a 650/650 lift-290/290-108 cl.solid flat tappet cam or 680/683-284/288-108cl roller cam.these are with 1.5 rockers,1.6 is even better.We used these cams in many builds.



This man has built more than anyone else you can name--Believe Him!
That 650 solid dialed in right--I like advanced to around 102 in a 440 and 105 in a 500 ( we usually race 1/8th) is one of the best cams in that combo on earth! Fiddle around with numbers until you go blind--it will still beat 90 % of the choices you will make--You were talking to another cam guru at Hughes--and ??
That 650 solid will shock you at how well it works--Period! It really needs stout springs and titanium retainers are a 100% MUST with it as well but when degreed correctly it is unbeatable with your combo-which is a classic BTW I have used dozens of them over the years and have never been unhappy. Depend on folks that have built Hundreds of big blocks not a few
Posted By: CHAPPER

Re: Cam Help RB 496 - 02/12/15 03:21 AM

Quote:

Looking to change the camshaft in my engine. The engine is a 496" RB with approx. 12.5-1 comp. Indy 440-1 heads (mild porting and bowl blend) 1050 dominator running E-85. the current camshaft is an older Hughes grind:HEV5663BS with 1.6 rockers INT .626" EXH .642" duration @.050 int: 256 exh: 265 lobe sep: 108 The car is 3020lbs with me in it, 4500 dynamic converter, 727 trans, 471 gears, 33" tire. Foot brake the car. It currently runs 6.20s in the 1/8th has been 9.70s in the 1/4. I had been told by Hughes I could use a little more camshaft and was hoping to get some opinions of what I should be looking for from some of you who know more than me. Thanks




3020#... That is light,,,the car doesn't look 'light'.
Posted By: 70blackfish

Re: Cam Help RB 496 - 02/12/15 04:42 AM

cool car....
sorry i didn't catch if you had a solid roller in there now,
Posted By: gregsdart

Re: Cam Help RB 496 - 02/12/15 02:54 PM

Quote:

I have been looking at another Hughes cam or maybe Howards. Not really tied to any brand just want to get the most bang for the buck so to speak. What do you guys think about: Hughes: HUG STL6872BS3-8 3 BOLT .421"/.426" LOBE LIFT and 268/272 -108šLSA or Maybe a Howards:HRS-722412-08 Lift .639/.639 with 1.5 rockers 272 int./272 exh. I am running 1.6 rockers and don't want to go so big it ruins the combination.


These cams leave hp on the table. As long as you match the converter to the cam, you can run a LOT more duration than you now have. Look at BGs recommendation, and mine with .200 duration numbers of 200 on the 290 cam and 197 on the mm305. Those cams come close to roller cam specs.
Of the roller cams I have used in motors like this, non were less than 280 @ .050 on the intake, and non were less than 197 duration at .200. This combo of 440-1 heads and 500 cubes work well with that much duration. High lift won't hurt you provided you have clearance and good springs. The extra lift is also what puts you where the heads flow well also. Mildly ported 440-1s don't reach full flow till .700+ lift. A common rule of thumb for best performance is to open the valve .35 times the intake valve diameter which is more than .700 with your heads.
I haven't run them, but the word is the newer Beehive springs are the hot deal, and worth looking into.
Posted By: 47hudson

Re: Cam Help RB 496 - 02/12/15 04:35 PM

Thanks for all the info, that's a lot bigger bump stick than what I was looking at. I will be changing the springs to match the cam but I am still running the original Indy rockers, retainers etc. that came on my heads, am I going to go beyond what these parts will regularly handle? I don't have much of a budget so I need to make sure my parts will last a few seasons. Other than the Hughes cam mentioned does anyone have a shelf part # for a good cam I need to purchase the cam lifters and springs soon.
Posted By: Eric

Re: Cam Help RB 496 - 02/12/15 05:01 PM

Quote:

The engine combo would love a 650/650 lift-290/290-108 cl.solid flat tappet cam or 680/683-284/288-108cl roller cam.these are with 1.5 rockers,1.6 is even better.We used these cams in many builds.



Thats the stick "the Man" put in my ride (.650) works very well and I run it pretty detuned.
Posted By: B G Racing

Re: Cam Help RB 496 - 02/12/15 05:11 PM

Quote:

Thanks for all the info, that's a lot bigger bump stick than what I was looking at. I will be changing the springs to match the cam but I am still running the original Indy rockers, retainers etc. that came on my heads, am I going to go beyond what these parts will regularly handle? I don't have much of a budget so I need to make sure my parts will last a few seasons. Other than the Hughes cam mentioned does anyone have a shelf part # for a good cam I need to purchase the cam lifters and springs soon.



We use these cams with the Indy rockers and retainers with good results.Choose a good spring with aprox.225 to 250 lbs on the seat and 500 to 600 lbs. open.For best upgrades use 10 degree titanium retainers and 10 degree locks then you can use a little more spring pressure if you want.With the setup we have mentioned you can get a lot of service and life.The cams can be purchased through Comp Cams and Indy.
Posted By: sixpackgut

Re: Cam Help RB 496 - 02/12/15 05:12 PM

i would change the converter to a 53-5500 before I change the cam. Even if you change the cam you will still need to change to converter
Posted By: 47hudson

Re: Cam Help RB 496 - 02/12/15 08:24 PM

We use these cams with the Indy rockers and retainers with good results.Choose a good spring with aprox.225 to 250 lbs on the seat and 500 to 600 lbs. open.For best upgrades use 10 degree titanium retainers and 10 degree locks then you can use a little more spring pressure if you want.With the setup we have mentioned you can get a lot of service and life.The cams can be purchased through Comp Cams and Indy.



Ok what I am coming up with is a Comp 23-650-5 cam, Comp 821-16 lifter, and Comp recommends a 925-16 spring? Sorry for asking so many questions but I would like to get all this nailed down so I can order some parts. Then I just need a summit discount code!

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Posted By: deaks

Re: Cam Help RB 496 - 02/12/15 08:32 PM

Cant help on the info but please post your results when you take it out because i'm thinking of giving this cam a try in my 440.
Mick
Posted By: 440Jim

Re: Cam Help RB 496 - 02/12/15 08:49 PM

Quote:

We use these cams with the Indy rockers and retainers with good results.Choose a good spring with aprox.225 to 250 lbs on the seat and 500 to 600 lbs. open.For best upgrades use 10 degree titanium retainers and 10 degree locks then you can use a little more spring pressure if you want.

Those pressures are a lot higher than the Comp 925-16 springs.
Posted By: 47hudson

Re: Cam Help RB 496 - 02/12/15 09:11 PM

Quote:

Quote:

We use these cams with the Indy rockers and retainers with good results.Choose a good spring with aprox.225 to 250 lbs on the seat and 500 to 600 lbs. open.For best upgrades use 10 degree titanium retainers and 10 degree locks then you can use a little more spring pressure if you want.

Those pressures are a lot higher than the Comp 925-16 springs.



I was just going off the "recommended parts" in the Comp catalog. If anyone could point me in the right direction it would be greatly appreciated!
Posted By: 47hudson

Re: Cam Help RB 496 - 02/12/15 09:12 PM

Quote:

i would change the converter to a 53-5500 before I change the cam. Even if you change the cam you will still need to change to converter



I have a PTC converter and I am going to try and send it in to see if it could be made to match my engine better.
Posted By: B G Racing

Re: Cam Help RB 496 - 02/13/15 06:02 PM

Quote:

Quote:

We use these cams with the Indy rockers and retainers with good results.Choose a good spring with aprox.225 to 250 lbs on the seat and 500 to 600 lbs. open.For best upgrades use 10 degree titanium retainers and 10 degree locks then you can use a little more spring pressure if you want.

Those pressures are a lot higher than the Comp 925-16 springs.




Those pressures I posted are for a roller cam.sorry for any confusion.The 925-16 spring is a little light at 100+ seat and 330+ open pressures but that is advertized at 1.900 installed height.Most solid flat tappet cams recommend the installed height at 1.875 or less.
Posted By: 47hudson

Re: Cam Help RB 496 - 02/15/15 01:28 AM

Thanks for all the information I really appreciate it. Its good to have a place to get good info. from other racers.
Posted By: gregsdart

Re: Cam Help RB 496 - 02/15/15 03:53 AM

I have heard there is a process that you can have done to a new flat tappet cam to further harden it. Might be a good investment? Also, lifters with center oiling hole in the face?
Posted By: 68-scatpack-rt

Re: Cam Help RB 496 - 02/15/15 01:32 PM

Why not call cam motion and have a custom cam ground? It's just about the same price as a "shelf" cam. Maybe a bit more but, for what you're doing, I'd think a tailored cam would be my first choice.
Posted By: BradH

Re: Cam Help RB 496 - 02/15/15 04:54 PM

Quote:

Quote:

i would change the converter to a 53-5500 before I change the cam. Even if you change the cam you will still need to change to converter



I have a PTC converter and I am going to try and send it in to see if it could be made to match my engine better.


Not sure what your target ET is, but you have room to go bigger on the cam now w/ the current converter. The suggestions I made were intended for the 'vert you have now.

But if you're looking for BIGGER gains, then I agree that an even bigger cam will require a converter change.
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