Cams that don't blow up motors
#1
Safety Car
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Cams that don't blow up motors
A cam swap for me is quite a ways off, but it's something I often think about. A mild cam with tighter LSA would likely provide me with a more pleasant power band that hits good and hard in the midrange, and it's actually the midrange that makes me want it as that's where the engine runs on most infields. I figure a custom grind is probably the best way to go, but my concern is what have you guys used that didn't require constant valve spring changing and doesn't break valve springs? I've heard if you keep lift around .580, then you're good to go and to stay away from the Comp XE lobes as they're pretty harsh. I'd prefer to keep the lighter style beehives, but the realist in me knows that the increase in reciprocating mass from duals would be far outweighed in performance by the additional 20+ degrees of intake duration. This is the 2nd engine I've had with such a wide LSA and compared to the narrower LSAs that I've had before, I can feel a difference even if it's mild.
#2
Drifting
The GMPP ASA cam works very well in road race applications without being hard on the valvetrain. At only .525 lift you would think it would not be a particularly good performer....but it is. Pulls hard from 3000-6500 while using beehive springs. Duration is 226/236 on a 110 lsa.
Not really necessary to twist beyond 6500. The ASA Lingenfelter motors made 400 hp to the wheels with this cam with nothing more than headers and a good tune.
We have also used a custom Crane grind with about 550 lift 232/242 112 lsa that also has proven to be a reliable performer, easy on the valve train and made about 15 more hp than the ASA cam.
hope this helps
Not really necessary to twist beyond 6500. The ASA Lingenfelter motors made 400 hp to the wheels with this cam with nothing more than headers and a good tune.
We have also used a custom Crane grind with about 550 lift 232/242 112 lsa that also has proven to be a reliable performer, easy on the valve train and made about 15 more hp than the ASA cam.
hope this helps
#3
Safety Car
Thread Starter
It does, I'm happy to see that I'm not the only person with this concern. I googled the ASA cam and found similar advocation for it. It also proves to me that the engine really is begging for a different pattern and that it doesn't need all that lift to give it a kick in the pants. Even with the same lift, when you add duration you give the valve that much more time to open and close which makes it easier on the springs than even the stock cam, doesn't it?
#5
The folks at Katech also have a really nice, race-proven cam in their Torquer series. Makes good power, not tough on the valvetrain.
#6
Former Vendor
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St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
I agree....
However there are some lobe families that are easier on drivetrain parts than others. Most of our G5 and G7 family of cams are fine, but some of the G6 cams are a bit on the aggressive side and we do have a road race version of those cams for guys that are going to track the cars or compete in a series.
As with anything you need to make sure all of the valve train is matched so that it will provide you with the needed service life.
However there are some lobe families that are easier on drivetrain parts than others. Most of our G5 and G7 family of cams are fine, but some of the G6 cams are a bit on the aggressive side and we do have a road race version of those cams for guys that are going to track the cars or compete in a series.
As with anything you need to make sure all of the valve train is matched so that it will provide you with the needed service life.
#8
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I've seen that before, and anything bigger than that makes me nervous. If that GM ASA cam were on a 112 and had .550 lift, it'd be more appealing, but I bet it'd still make the power I'm after. So many of the aftermarket offerings are right up on and over the .6 mark. Even the Katech and LG grinds make me a little nervous, maybe I'm just paranoid? For every success story, there's a fail story, but a blowup would be a season ender for sure. If I get a mediocre non-man cam and I get 25hp/tq but leave 10-15 on the table, I'd be OK with that. By my calculations, to stay in the new TT2 class in NASA I absolutely cannot exceed 400whp, but I can have all the torque I want. If it came to it, I'd run a cammed car with a restrictor plate to kill off a little top end just to get that fat midrange.
#11
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#13
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Anthony
I know you guys build a lot of engines, but Most ppl dont rebuild engines each or every other race. or have the funds to rebuild engine. They would like an engine to last at least one year before rebuilding.
I know you guys build a lot of engines, but Most ppl dont rebuild engines each or every other race. or have the funds to rebuild engine. They would like an engine to last at least one year before rebuilding.
#14
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St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
The World Challenge engines would go almost a season....but generally put the spare in roughly 1/2 way through the season. The ALMS car was rebuild every 35-40 hrs of run time. Remember we would have to do the entire LeMans run on a single engine, possibly a practice engine but once qualifying is over it has to stay in the car.
Your building a race car, not a Semi that has to go 1,000,000 miles. Things have to be changed, depending on what you put in it, and what your race season involves when you have to change it or rebuild. To me a set of valve springs is nothing compared to the amount of tires, rotors, pads.....
#15
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I've suggested the ASA cam to several guys in your same boat, so far I haven't been able to put an ASA cam into an LS6 to find out exactly what kind of improvement it will make but I put a Hot Cam in an LS2 and it made 31 hp and 19 ft lbs of tq - I would expect a little better numbers out of the ASA cam - if you make over 400 hp that's a good thing, it's really easy to pull a little timing exactly where you want it.
#16
Le Mans Master
I think an LS6 with CAI, headers and the ASA cam is going to become the new normal for ST2/TT2 cars.
I've suggested the ASA cam to several guys in your same boat, so far I haven't been able to put an ASA cam into an LS6 to find out exactly what kind of improvement it will make but I put a Hot Cam in an LS2 and it made 31 hp and 19 ft lbs of tq - I would expect a little better numbers out of the ASA cam - if you make over 400 hp that's a good thing, it's really easy to pull a little timing exactly where you want it.
I've suggested the ASA cam to several guys in your same boat, so far I haven't been able to put an ASA cam into an LS6 to find out exactly what kind of improvement it will make but I put a Hot Cam in an LS2 and it made 31 hp and 19 ft lbs of tq - I would expect a little better numbers out of the ASA cam - if you make over 400 hp that's a good thing, it's really easy to pull a little timing exactly where you want it.
#17
Safety Car
Thread Starter
Seems everyone either loves these cams or hates them. Those that seek them are after the same thing I am: valvatrain reliability. Few are trying to keep hp at bay with it though. I'm wondering if it'll plug up some cats, if so I'll just go catless on the h pipe. Seems with a good tune, it'll idle and drive decently, but I would like to hear more feedback on that. It's going to be more involved to tune that autoVE'ing my truck and calling it a day, so the install will definitely be in the off season so I have enough time to figure it out. It's got a buttload of overlap, which is why it needs good exhaust to come alive. Also why the midrange is so fat I bet. From the graph I saw, power starts dropping about where the stock cam does.
#19
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St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
Ok, so that makes no point to why you were saying don't put a bigger cam in the car.
It isn't lift per say that kills valve train components, it is the actual profile design of the cam and the ramp rates both opening and closing that beat up seats and valves...
Even at that, the springs take the brunt of the forces anyway so when you might have to 'refresh' a road race engine with a bigger cam typically it is going to be valve springs first...if you are picky enough to worry about the last 5-10hp as the engine wears it is going to be regrinding the valves and valve seats to put that 'knife' edge so to speak on them again and make sure the angles are proper once again.
It isn't lift per say that kills valve train components, it is the actual profile design of the cam and the ramp rates both opening and closing that beat up seats and valves...
Even at that, the springs take the brunt of the forces anyway so when you might have to 'refresh' a road race engine with a bigger cam typically it is going to be valve springs first...if you are picky enough to worry about the last 5-10hp as the engine wears it is going to be regrinding the valves and valve seats to put that 'knife' edge so to speak on them again and make sure the angles are proper once again.
#20
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I think the thing that makes me the most uneasy is not knowing what I don't know. AFAIK, overlays of cam profiles aren't readily available. If they were, I wonder how difficult it'd be to look at the drawing on paper and know whether or not the cam was more gentle enough than say, a Comp XE lobe. I know this stuff can be graphed, as the ramp rates of a cam can be graphed as the derivative of acceleration or the 2nd derivative of velocity. It's a simple function, so if it can be graphed it can also be laid out on a table with numbers. Trouble is, what number are acceptable and what numbers aren't? Since I'm not racing per say, rather competing and shooting for a pretty small goal cam-wise, it stands to reason that I can stay mild on the lift and not worry about splitting hairs over which .580 lobe is gentler than the other. I don't think the stock cam is the answer here. Sure I could cheat and slap a FAST 92 on there just to hit 400whp without a cam, but a cam with stock LS6 intake would be a lot healthier under the curve.