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Re: why would a stock street hemi have only 5in vacuum ? [Re: TRENDZ] #1533346 11/17/13 07:33 PM 11/17/13 07:33 PM
Joined: Jan 2004 Posts: 8,294 fredericksburg,va C cudaman1969 master
cudaman1969 master C Joined: Jan 2004 Posts: 8,294 fredericksburg,va	From the 69 service manual, cam- 284 deg. 467 lift not even close to a 292 cam. cranking pressure 150-205 psi. Change that cam!

Re: why would a stock street hemi have only 5in vacuum ? [Re: ogopogo] #1533347 11/17/13 10:52 PM 11/17/13 10:52 PM
Joined: Mar 2006 Posts: 2,675 Mt. Eden Ky. Hemi Allstate master
Hemi Allstate master Joined: Mar 2006 Posts: 2,675 Mt. Eden Ky.	Quote: Cab, yes by late timing I mean the intake is opening at 35-36 btdc when it should be 38 btdc. I have checked the plug on the bottom of the intake.Timing was a little erratic with the oem dual point but i replaced it and timing is good now. How much of a vaccum loss would I see if the brake booster was bad? what do you guys recommend to seal the head stud threads? Permatex makes a white thread sealer that I use. Permatex # PX 56521 If the studs are not sealed, you will draw oil passed the threads that you will see in the intake ports. Any chance the valves are adjusted too tight? Last edited by Hemi Allstate; 11/18/13 11:42 AM.

Re: why would a stock street hemi have only 5in vacuum ? [Re: ogopogo] #1533348 11/18/13 12:39 AM 11/18/13 12:39 AM
Joined: Oct 2003 Posts: 2,537 PORT ALBERNI , BC., CANADA superwrench master
superwrench master Joined: Oct 2003 Posts: 2,537 PORT ALBERNI , BC., CANADA	Just to give you a comparison of sorts.....I have a Racer Brown SSH-44 for a Hemi sitting on my shop shelf. It's a hydraulic 292* .510 lift cam that Direct Connection had 30 years ago. The reason it's on the shelf is for the very reason's you have pointed out in your post.....NO vacuum, pig rich running at idle and low speed, and all the other associated woes that a cam like that creates. My hemi car doesn't have Power brakes,but the 6" of vacuum that I had wouldn't have run them anyways. My is you need a cam down in the 276-280 maximum (Not at .050 either) That cam made the car haul like hell up top, but you couldn't poke around town with it and enjoy the car. Just the stock solid in the car now, and that's what's staying in it.

Re: why would a stock street hemi have only 5in vacuum ? [Re: TRENDZ] #1533349 11/18/13 11:36 AM 11/18/13 11:36 AM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	With most cams you won't see much change unless you move it 3 to 4 degrees.One tooth can be a large move in degrees.If your going to move the cam do it correctly.Advancing moves the intake valve closser to the piston,retarding moves the exhaust closer to the piston.Don't guess at it. [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: why would a stock street hemi have only 5in vacuum ? [Re: B G Racing] #1533350 11/18/13 12:15 PM 11/18/13 12:15 PM
Joined: Jun 2006 Posts: 5,163 CT GTX MATT master
GTX MATT master Joined: Jun 2006 Posts: 5,163 CT	Quote: With most cams you won't see much change unless you move it 3 to 4 degrees.One tooth can be a large move in degrees.If your going to move the cam do it correctly.Advancing moves the intake valve closser to the piston,retarding moves the exhaust closer to the piston.Don't guess at it. I believe one cam tooth is something like 15 degrees, at least thats what I've heard and it seems to make sense Now I need to pin those needles, got to feel that heat Hear my motor screamin while I'm tearin up the street

Re: why would a stock street hemi have only 5in vacuum ? [Re: GTX MATT] #1533351 11/26/13 06:53 PM 11/26/13 06:53 PM
Joined: Oct 2003 Posts: 1,795 BC Canada O ogopogo OP top fuel
ogopogo OP top fuel O Joined: Oct 2003 Posts: 1,795 BC Canada	ok my comp 278 will be here this afternoon,comp recommends cl @ 108, does that sound good for this cam? specs http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=753&sb=0

Re: why would a stock street hemi have only 5in vacuum ? [Re: ogopogo] #1533352 11/26/13 10:45 PM 11/26/13 10:45 PM
Joined: Aug 2003 Posts: 43,230 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,230 Bend,OR USA	Quote: ok my comp 278 will be here this afternoon,comp recommends cl @ 108, does that sound good for this cam? specs http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=753&sb=0 Nope Put it in at 102 to 105 Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: why would a stock street hemi have only 5in vacuum ? [Re: Cab_Burge] #1533353 11/27/13 12:42 AM 11/27/13 12:42 AM
Joined: Oct 2003 Posts: 1,795 BC Canada O ogopogo OP top fuel
ogopogo OP top fuel O Joined: Oct 2003 Posts: 1,795 BC Canada	Ok, well I just degreed it and it came in at 107.I can move it in 4 degree increments if i want.this is a stock engine keep in mind in a street only car. The comp lifters are kinda strange,the pushrod cup sits down farther in the lifter and is loose,you can rattle it.the pushrod cup sits .087 lower down than the cup in the lifters im replacing so that is going to affect my pushrod length again..............

Re: why would a stock street hemi have only 5in vacuum ? [Re: ogopogo] #1533354 11/28/13 01:29 AM 11/28/13 01:29 AM
Joined: Jan 2004 Posts: 8,294 fredericksburg,va C cudaman1969 master
cudaman1969 master C Joined: Jan 2004 Posts: 8,294 fredericksburg,va	I don't think you will see any more vacuum with that cam then the one you had. You need at least 112 or more centerline. Just a street engine-right?

Re: why would a stock street hemi have only 5in vacuum ? [Re: cudaman1969] #1533355 11/28/13 01:42 AM 11/28/13 01:42 AM
Joined: May 2003 Posts: 6,566 Downtown Roebuck Ont Twostick Still wishing...
Twostick Still wishing... Joined: May 2003 Posts: 6,566 Downtown Roebuck Ont	Going from 76 deg of overlap to 62 has got to help. Kevin

Re: why would a stock street hemi have only 5in vacuum ? [Re: Twostick] #1533356 11/28/13 02:07 AM 11/28/13 02:07 AM
Joined: Jan 2004 Posts: 8,294 fredericksburg,va C cudaman1969 master
cudaman1969 master C Joined: Jan 2004 Posts: 8,294 fredericksburg,va	I put one in my 440 and with the crane bleed off lifters only got 9-10 inchs of vacuum. Brake booster was marginal and carb needed work. So I put stock cam back in.

Re: why would a stock street hemi have only 5in vacuum ? [Re: cudaman1969] #1533357 11/28/13 10:19 AM 11/28/13 10:19 AM
Joined: Oct 2003 Posts: 1,795 BC Canada O ogopogo OP top fuel
ogopogo OP top fuel O Joined: Oct 2003 Posts: 1,795 BC Canada	I did some online research before buying this cam and two moparts members have it in stock resto cars and are happy with it,I thought it speced out fairly mild? Sooo,Cab says I should install it at 102 and cudaman is saying 112? Im getting confused here ! My local engine guy as well as BGR are saying 108 is good!

Re: why would a stock street hemi have only 5in vacuum ? [Re: ogopogo] #1533358 11/28/13 12:16 PM 11/28/13 12:16 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: I did some online research before buying this cam and two moparts members have it in stock resto cars and are happy with it,I thought it speced out fairly mild? Sooo,Cab says I should install it at 102 and cudaman is saying 112? Im getting confused here ! My local engine guy as well as BGR are saying 108 is good! NO NO... they are talking 2 different things... Cab is saying to INSTALL at 102.. Cuda is talking LSA (lobe separation angle).... from your initial post you said you moved the timing pointer.... if thats the case your timing would be based on the od pointer... when installing a cam you set TDC on the piston then slide the cover on to verify the zero... so if you moved the pointer you changed a lot of factors.... back to the cam numbers... like Cab said I would INSTALL it at 102 or so for the lower end torque A cam that is installed retarded(as in 109 or higher) will have low vac

Re: why would a stock street hemi have only 5in vacuum ? [Re: GTX MATT] #1533359 11/28/13 12:17 PM 11/28/13 12:17 PM
Joined: Feb 2008 Posts: 715 Central TEXAS!!!! sr4440 super stock
sr4440 super stock Joined: Feb 2008 Posts: 715 Central TEXAS!!!!	Quote: Quote: With most cams you won't see much change unless you move it 3 to 4 degrees.One tooth can be a large move in degrees.If your going to move the cam do it correctly.Advancing moves the intake valve closser to the piston,retarding moves the exhaust closer to the piston.Don't guess at it. I believe one cam tooth is something like 15 degrees, at least thats what I've heard and it seems to make sense very close, 14.4 degrees (25 crank teeth / 360 degrees)or (50 cam teeth / 720 degrees) Joe Without Data, you’re just another guy with an opinion.

Re: why would a stock street hemi have only 5in vacuum ? [Re: ogopogo] #1533360 11/28/13 01:25 PM 11/28/13 01:25 PM
Joined: Jan 2004 Posts: 8,294 fredericksburg,va C cudaman1969 master
cudaman1969 master C Joined: Jan 2004 Posts: 8,294 fredericksburg,va	Quote: I did some online research before buying this cam and two moparts members have it in stock resto cars and are happy with it,I thought it speced out fairly mild? Sooo,Cab says I should install it at 102 and cudaman is saying 112? Im getting confused here ! My local engine guy as well as BGR are saying 108 is good! Just looked at some cams and Crane has a 660091 cam,284-294 with 112 lobe separation - 1500-5200 rpm great idle. This is what I'm saying, a good street cam that will give you the vacuum you need for stock carbs.

Re: why would a stock street hemi have only 5in vacuum ? [Re: ogopogo] #1533361 11/28/13 01:29 PM 11/28/13 01:29 PM
Joined: Mar 2008 Posts: 5,746 Ontario, Canada Dodgem master
Dodgem master Joined: Mar 2008 Posts: 5,746 Ontario, Canada	Quote: I did some online research before buying this cam and two moparts members have it in stock resto cars and are happy with it,I thought it speced out fairly mild? Sooo,Cab says I should install it at 102 and cudaman is saying 112? Im getting confused here ! My local engine guy as well as BGR are saying 108 is good! I would install that cam 102 to 105 Last edited by Dodgem; 11/28/13 01:31 PM.

Re: why would a stock street hemi have only 5in vacuum ? [Re: cudaman1969] #1533362 11/28/13 02:55 PM 11/28/13 02:55 PM
Joined: Aug 2003 Posts: 43,230 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,230 Bend,OR USA	Quote: Quote: I did some online research before buying this cam and two moparts members have it in stock resto cars and are happy with it,I thought it speced out fairly mild? Sooo,Cab says I should install it at 102 and cudaman is saying 112? Im getting confused here ! My local engine guy as well as BGR are saying 108 is good! Just looked at some cams and Crane has a 660091 cam,284-294 with 112 lobe separation - 1500-5200 rpm great idle. This is what I'm saying, a good street cam that will give you the vacuum you need for stock carbs. Hemiroid motors don't like wide lobe seperation angles like above 110, even a street blower motor Same thing on close lobe centers(closer than 106), them dang hemirod motors are a pain to get right Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: why would a stock street hemi have only 5in vacuum ? [Re: Cab_Burge] #1533363 11/28/13 03:39 PM 11/28/13 03:39 PM
Joined: Mar 2006 Posts: 9,857 MI, usa dvw master
dvw master Joined: Mar 2006 Posts: 9,857 MI, usa	Quote: Quote: Quote: I did some online research before buying this cam and two moparts members have it in stock resto cars and are happy with it,I thought it speced out fairly mild? Sooo,Cab says I should install it at 102 and cudaman is saying 112? Im getting confused here ! My local engine guy as well as BGR are saying 108 is good! Just looked at some cams and Crane has a 660091 cam,284-294 with 112 lobe separation - 1500-5200 rpm great idle. This is what I'm saying, a good street cam that will give you the vacuum you need for stock carbs. Hemiroid motors don't like wide lobe seperation angles like above 110, even a street blower motor Same thing on close lobe centers(closer than 106), them dang hemirod motors are a pain to get right I built a Hemi for my buddy's 69 Road Runner. A friend recommended a cam with a 114 LCA. The car Idles like a 318. Has great low end and pulls to 6000. All stock (still has the original exhaust from 69) 13.00@107. I would have never chosen this cam but he swore it would work. He was correct. Doug

Re: why would a stock street hemi have only 5in vacuum ? [Re: dvw] #1533364 11/28/13 03:44 PM 11/28/13 03:44 PM
Joined: Aug 2003 Posts: 43,230 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,230 Bend,OR USA	Until you run the same Hemi motor with the same grind on different lobe centers you will not know the differences bewteen the two I have done dyno testing and then seen the results between the two at the drag strip, if you want the fastest combination then you should do those tests also I have to keep in mind what is important to one person may not have the same importance to someone else I like going faster than the next guy Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: why would a stock street hemi have only 5in vacuum ? [Re: dvw] #1533365 11/28/13 09:58 PM 11/28/13 09:58 PM
Joined: Aug 2003 Posts: 43,230 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,230 Bend,OR USA	I built a Hemi for my buddy's 69 Road Runner. A friend recommended a cam with a 114 LCA. The car Idles like a 318. Has great low end and pulls to 6000. All stock (still has the original exhaust from 69) [Email]13.00@107.[/Email] I would have never chosen this cam but he swore it would work. He was correct. Doug I wouldn't want a 426 Street hemi motor to idle like a 318,or pull like one either Evidentily your buddy does, This is America, you can have it your way BTE, all the stock 426 Street Hemi motors(factory stock, not blue printed stock) I have owned or driven pull like gangbusters to 7000 RPM For those that don't know the difference chararestics(SP?) of different lobe seperation angles on the same cam grinds, usually tighter LSA will increase bootom end power (HP and torque), that also makes the idle choppy and the motor will have less intake manifold vacume at idle. Widening the lobe seperation angle usually looses bottom end HP and Torque and moves the peak HP (power band) higher, it does make more manifold vacume at idle A very succesful old time drag racer told me early in my racing career to focus on the first 100 ft of the track, the rest of it would take care of itself I found that to work very well for me The first 12 inches of the track takes the longest time per inch to move the car Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

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