Does a cam help improve spool up?

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getblown5.9

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I know they can drop EGT's with better airflow, as well as broaden the power band, but does it get the wider power and by spooling charger quicker?

The reason I ask is because I want to add a cam next winter, and lately i have been running some huge fuel dumping sticks that are noticably more powerful on the top end, but spool the charger so slow with so much fuel and not much air. Its impossible to drive clean with them, even when driving like grandpa.

Would a cam help with situations where a large charger is being used, and some pretty large sticks? At half throttle and low-midrange rpms would the cam give enough airflow to make the truck more drivable with less smoke?
 
I guess it depends on the profile you go with but I don't think my Helix II helps with anything down low? Helps mucho in the upper rpm though, seems like on my rig 1800 is where the chargers hit and it pulls real nice until I run out balls to keep my foot in it. I know a few guys running a street cut profile that PDR sells and they like them for towing, they claim to spool sooner? Perhaps the Helix I will spool sooner also?
 
If you go with the correct profile it will help you, but you can overfuel and no amount of atmosphere will help with that. You basically have to match turbo, cam and other power adders to get everything perfect. But yes a cam can help in the spool department.
 
I picked up about 8-9 psi of boost on the dyno. So yes, it does improve spool up.
 
Ratsun said:
I know a few guys running a street cut profile that PDR sells and they like them for towing, they claim to spool sooner?
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I've heard the same about their cams.
Little bit better spool up and lower egts.
Not as good as twins, but better'n a stock cam.
 
lmills said:
I picked up about 8-9 psi of boost on the dyno. So yes, it does improve spool up.
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see on the street i see 52psi, and on the dyno i see about 48-50psi, so max psi is not what i am after.

I was wondering if the increased airflow through the entire rpm range would help with spooling a medium to large single.

My DDP 200 sticks were a great match for the Silver Bullet, but going larger is def not helping anything now...it just spews soot and takes until 2800rpms to finally hit hard.

2nd, 3rd, and most of 4th are useless with the BIG injectors. they just blow smoke, get me about 10psi max, and run out to 3500rpms before the charger can come up. I can't wait to go back to my old injectors!
 
lmills said:
I picked up about 8-9 psi of boost on the dyno. So yes, it does improve spool up.
Click to expand...

I thought most saw a drop in total boost once an aftermarket cam was installed.
 
With a helix 2 cruising with no boost, it takes literally 10 seconds for the turbo to spool down when I let off the throttle. Boost is down, but whistle is way up. I think it'd help with driveability in low/no boost situations once you get some decent sticks back in there.
 
Ph4tty said:
With a helix 2 cruising with no boost, it takes literally 10 seconds for the turbo to spool down when I let off the throttle. Boost is down, but whistle is way up. I think it'd help with driveability in low/no boost situations once you get some decent sticks back in there.
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yea i hope so...i really hope it will help next year when this truck gets a p-pump so i can still take it out on the weekends to play, even tho it will be primarily a puller.

these buddha hose nozzles are really fun from about 30-55psi, but before that, the truck seems lazy, and smokes alot. i didnt realize just how bad it was til I put 3200lbs of concrete in the bed, then the truck was a real dog until 30+ psi when the power came in and it would get out of its own way.

PS-you know your truck is overloaded when you have to take your u-joint shield off because its rubbing the yoke on the DS.
 
dzlfarmboy said:
I thought most saw a drop in total boost once an aftermarket cam was installed.
Click to expand...

Yeah, I was about to comment on that. I lost 12 psi with the helix 2 and a ps64- from 47 lbs to 35. Max power did come in 300 rpms sooner with the cam btw
 
if all things remain the same, a "properly built and designed" cam will increase spool up, and drop boost.

it will spool quicker because it is letting exhaust out quicker and for a longer period--thus pushing the charger faster/ sooner.

it will drop boost by letting more air in the motor and reducing the restriction on the motor ( boost is a restriction) while making it more efficient.
 
One cam builder told me that the reason some of the big name cams drop boost is because there's to much overlap and it's sending some of the boost out with the exhaust.
 
Ph4tty said:
Yeah, I was about to comment on that. I lost 12 psi with the helix 2 and a ps64- from 47 lbs to 35. Max power did come in 300 rpms sooner with the cam btw
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Wow you really seen some big changes!
I don't really know how much if any boost I lost as my 60# gauge gets pinned pretty quickly but I don't think it was very much. Lower rpms didn't change allot either ( SOTP meter) however I did notice a large gain in how aggressively the power comes on around 1800rpm and stays all the way up. It really lights the chargers harder it seems I don't know if its me or what but it also seems like when I'm cruising @60mph empty my boost is up, it hangs around 10psi where as I don't remember it being there before?
 
how much should you have done before you start looking into a cam for the buy to be logical?
 
The same cam affects 3rd gens and 2nd gens differently. The 3rd gens seem to spool a bunch sooner, the 04.5 with a cam would build a few psi rev'ing in neutral. The same truck wouldn't do it with a stock cam. Mine won't do that with the same cam, but the airflow range was extended beyond 4k as shown on the dyno.

brandon.
 
joefarmer said:
The same cam affects 3rd gens and 2nd gens differently. The 3rd gens seem to spool a bunch sooner, the 04.5 with a cam would build a few psi rev'ing in neutral. The same truck wouldn't do it with a stock cam. Mine won't do that with the same cam, but the airflow range was extended beyond 4k as shown on the dyno.

brandon.
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I would guess that the third gens see more improvement due to the efficiencies of the 24v head opposed to the 12v?
Hey Brandon hows those springs? Get a chance to try them yet?
 
BgBlDodge said:
One cam builder told me that the reason some of the big name cams drop boost is because there's to much overlap and it's sending some of the boost out with the exhaust.
Click to expand...

Too much overlap........works good on top, bad on bottom! Same goes with big centerline, a 112 works great up top but had nothing on the bottom. No I'm no Cam guy........this was experience.

Jim
 
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