LT1 Hot Cam Advice, let's do and "advanced" look at this
Registered User
Joined: Aug 1999
Posts: 449
From: Where St. Augustine won't grow
FWIW, it sounds like Brett isn't necessarily saying the HOT cam is too big for a stock motor, but rather the same performance can be had with less duration.
Alex,
The Doc is right on. A degree or two of advance under light throttle/sub 2K RPM driving makes a HUGE difference in responsiveness. But yeah, it's just something that must be sacraficed in 91 octane owl ****.
Alex,
The Doc is right on. A degree or two of advance under light throttle/sub 2K RPM driving makes a HUGE difference in responsiveness. But yeah, it's just something that must be sacraficed in 91 octane owl ****.
Registered User
Joined: Jan 2001
Posts: 2,148
From: Bay Area, CA
Originally posted by max929
I have pinging with my recently installed cam. (hotcam/ppd heads with 2.00/1.6 int/exh and Slp midlength headers w/chip from pcmforless) Should I send the chip back for retuning. I also have an idle stumble and part throttle stumble.
I have pinging with my recently installed cam. (hotcam/ppd heads with 2.00/1.6 int/exh and Slp midlength headers w/chip from pcmforless) Should I send the chip back for retuning. I also have an idle stumble and part throttle stumble.
Jim, your probably right about that, not just on the board but locally as well I know at least one person who made good power with less intake duration, somewhere over 300 with stock heads. I forget the cam company but its not one you see on CZ hardly at all, I think it was a 211/225 or something, maybe an Ultradyne...
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Joined: Feb 2002
Posts: 960
Originally posted by Maldo
Bret,
I think TPIS answer is a load of crap.
The hot cam is a pretty small cam in my opinion.
Yes the hot cam will be a pig (at low rpm) if the computer is not programmed but that goes for most after market cams with LSA of 112. Remember your pcm is programmed for a smaller cam with a larger LSA of around 115 –116. I have talked with TPIS on occasion and I believe they are into selling their own stuff (that goes for most companies)
but their answer holds no water and it’s a load of crap.
If you do not plan to reprogram your pcm then I would stick with a cam with a LSA of around 114.
I just recently rebuilt my motor and did a few upgrades in the process and one of them was a bigger cam. (Custom comp extreme blower cam 224/236 with 114 lsa). This cam idles really well (at 900rpm with a little lope) and had no bucking or surging problems. (All this with stock programming) I did not install my blower until I had about 1500 miles on it.
To tell you the truth I was really surprised how well it preformed with out the blower and would recommend this cam to anyone who does not want to reprogram their PCM. (but with any cam change you will not get max power unless you reprogram the pcm)
I know a lot of people who run LT4 hot cams who had the pcm reprogrammed without any problems. In fact most step up to a bigger cam because is to small. I thumb my nose to anyone who tells you that the lt4 hot cam is to big .
Jim
Bret,
I think TPIS answer is a load of crap.
The hot cam is a pretty small cam in my opinion.
Yes the hot cam will be a pig (at low rpm) if the computer is not programmed but that goes for most after market cams with LSA of 112. Remember your pcm is programmed for a smaller cam with a larger LSA of around 115 –116. I have talked with TPIS on occasion and I believe they are into selling their own stuff (that goes for most companies)
but their answer holds no water and it’s a load of crap. If you do not plan to reprogram your pcm then I would stick with a cam with a LSA of around 114.
I just recently rebuilt my motor and did a few upgrades in the process and one of them was a bigger cam. (Custom comp extreme blower cam 224/236 with 114 lsa). This cam idles really well (at 900rpm with a little lope) and had no bucking or surging problems. (All this with stock programming) I did not install my blower until I had about 1500 miles on it.
To tell you the truth I was really surprised how well it preformed with out the blower and would recommend this cam to anyone who does not want to reprogram their PCM. (but with any cam change you will not get max power unless you reprogram the pcm)
I know a lot of people who run LT4 hot cams who had the pcm reprogrammed without any problems. In fact most step up to a bigger cam because is to small. I thumb my nose to anyone who tells you that the lt4 hot cam is to big .
Jim
Registered User
Joined: Jan 2001
Posts: 691
From: Jacksonville, FL
Originally posted by D James
not to break off subject but Iwas wondering how much power you felt from this cam(224/236). I just ordered it and plan on supercharging, but not for another year or so, would you have gone bigger or is it a perfect street blower cam. Should I go for tuning when I get it in, or wait for the charger, just wondering since you said it runs real well without it, hate to spend more money for only 5-10 hp thanks!
not to break off subject but Iwas wondering how much power you felt from this cam(224/236). I just ordered it and plan on supercharging, but not for another year or so, would you have gone bigger or is it a perfect street blower cam. Should I go for tuning when I get it in, or wait for the charger, just wondering since you said it runs real well without it, hate to spend more money for only 5-10 hp thanks!
Hi, Yes this cam is awesome I have about 5 k on the motor since I rebuild it. I must say there was a huge difference between the smaller blower cam I had in before. Yes I would definitely recommend this cam (get the low lift version because it is not as harsh on the valve train for everyday use)
Also I see you have long tubes and true duals you should be able to click off easy 12’s without a problem (with the stock tuning).
Also if anyone is interested I have some sound clips of what it sound like on my car. Even if you did not have a blower I would still recommend this cam. It as just enough lope to tell someone it is not a stocker. Also as I sated before no drive-ability problems and it pulls hard all the way to 6 grand without breaking a sweat.
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Joined: Feb 2002
Posts: 960
Sweet, thanks for the info, I've been seeing lately all these people with big cams saying it perfect for the street, and since I haven't messed with to many cams, zero blower cams It made me worry a little bit with the large spread in duration and the 114 LSA. I would be interested in hearing a soundclip, I imagine it sounds similar to the cc 305, but not exactly the same.
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Joined: Dec 1969
Posts: 10,745
From: Buffalo, New York
I have resisted posting to this thread, 'cause I have expressed my cam ideas often enough that I am sure many are tired of hearing them. But the idea that the 224/236XE cam is "small" wrt a centrifugal SC setup needs to be addressed. You can make 600+ rwhp with a smaller cam ( a la last years 214/224 in my car making 613rwhp) and not give up low end and midrange. For most setups, a larger cam will not make more hp. That's because once you max out the blower, it just aint gonna flow any more air regardless of intake duration. Very different than an NA setup, to say the least.
I would not recommend the 224/236 cam unless you are running a big blower. It won't do any good, will harm the low end and mid range, and may actually make less top end if the rest of the specs increase overlap. The 224/236XE lobes should be ground with a 116LSA for a blower car. 114 degrees is too narrow. And the 31xx (high lift) lobes should be used as well.
Rich Krause
I would not recommend the 224/236 cam unless you are running a big blower. It won't do any good, will harm the low end and mid range, and may actually make less top end if the rest of the specs increase overlap. The 224/236XE lobes should be ground with a 116LSA for a blower car. 114 degrees is too narrow. And the 31xx (high lift) lobes should be used as well.
Rich Krause
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Joined: Jan 2001
Posts: 691
From: Jacksonville, FL
Originally posted by rskrause
I have resisted posting to this thread, 'cause I have expressed my cam ideas often enough that I am sure many are tired of hearing them. But the idea that the 224/236XE cam is "small" wrt a centrifugal SC setup needs to be addressed. You can make 600+ rwhp with a smaller cam ( a la last years 214/224 in my car making 613rwhp) and not give up low end and midrange. For most setups, a larger cam will not make more hp. That's because once you max out the blower, it just aint gonna flow any more air regardless of intake duration. Very different than an NA setup, to say the least.
I would not recommend the 224/236 cam unless you are running a big blower. It won't do any good, will harm the low end and mid range, and may actually make less top end if the rest of the specs increase overlap. The 224/236XE lobes should be ground with a 116LSA for a blower car. 114 degrees is too narrow. And the 31xx (high lift) lobes should be used as well.
Rich Krause
I have resisted posting to this thread, 'cause I have expressed my cam ideas often enough that I am sure many are tired of hearing them. But the idea that the 224/236XE cam is "small" wrt a centrifugal SC setup needs to be addressed. You can make 600+ rwhp with a smaller cam ( a la last years 214/224 in my car making 613rwhp) and not give up low end and midrange. For most setups, a larger cam will not make more hp. That's because once you max out the blower, it just aint gonna flow any more air regardless of intake duration. Very different than an NA setup, to say the least.
I would not recommend the 224/236 cam unless you are running a big blower. It won't do any good, will harm the low end and mid range, and may actually make less top end if the rest of the specs increase overlap. The 224/236XE lobes should be ground with a 116LSA for a blower car. 114 degrees is too narrow. And the 31xx (high lift) lobes should be used as well.
Rich Krause
Hi Rich,
I am going to have to disagree with you (in the most polite way) Yes you have a good point but I have noticed a substantial gain in top end power that I never had before with my smaller blower cam (I run a 6# pd)
I currently see only about 4 # of boost. (The belt slips a little) and I am still able to roast the tires at will
To tell you the truth I am glad to take a hit on low end torque (but only slightly) because with a blower we all know you can’t put the power down with street tires anyway so you end up loosing to a slower car (lol) (also it’s easier on parts) I understand your point but I am running stock heads and the cam helps make up for the stock heads. I was in the same boat with a smaller blower cam but the new cam makes all the difference and it has the top end punch I was looking for which I did not get with the smaller cam.
This cam does not suffer from any low speed problems, no surging etc.
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Joined: Mar 2000
Posts: 186
I'm curious, do you have before and after dyno runs or track runs?
-Alex
-Alex
Originally posted by Maldo
Hi Rich,
I am going to have to disagree with you (in the most polite way) Yes you have a good point but I have noticed a substantial gain in top end power that I never had before with my smaller blower cam (I run a 6# pd)
I currently see only about 4 # of boost. (The belt slips a little) and I am still able to roast the tires at will
To tell you the truth I am glad to take a hit on low end torque (but only slightly) because with a blower we all know you can’t put the power down with street tires anyway so you end up loosing to a slower car (lol) (also it’s easier on parts) I understand your point but I am running stock heads and the cam helps make up for the stock heads. I was in the same boat with a smaller blower cam but the new cam makes all the difference and it has the top end punch I was looking for which I did not get with the smaller cam.
This cam does not suffer from any low speed problems, no surging etc.
Hi Rich,
I am going to have to disagree with you (in the most polite way) Yes you have a good point but I have noticed a substantial gain in top end power that I never had before with my smaller blower cam (I run a 6# pd)
I currently see only about 4 # of boost. (The belt slips a little) and I am still able to roast the tires at will
To tell you the truth I am glad to take a hit on low end torque (but only slightly) because with a blower we all know you can’t put the power down with street tires anyway so you end up loosing to a slower car (lol) (also it’s easier on parts) I understand your point but I am running stock heads and the cam helps make up for the stock heads. I was in the same boat with a smaller blower cam but the new cam makes all the difference and it has the top end punch I was looking for which I did not get with the smaller cam.
This cam does not suffer from any low speed problems, no surging etc.
Banned
Joined: Aug 2001
Posts: 3,505
From: looking for a flow bench so Brook and I can race
Originally posted by rskrause
I have resisted posting to this thread, 'cause I have expressed my cam ideas often enough that I am sure many are tired of hearing them. But the idea that the 224/236XE cam is "small" wrt a centrifugal SC setup needs to be addressed. You can make 600+ rwhp with a smaller cam ( a la last years 214/224 in my car making 613rwhp) and not give up low end and midrange. For most setups, a larger cam will not make more hp. That's because once you max out the blower, it just aint gonna flow any more air regardless of intake duration. Very different than an NA setup, to say the least.
I would not recommend the 224/236 cam unless you are running a big blower. It won't do any good, will harm the low end and mid range, and may actually make less top end if the rest of the specs increase overlap. The 224/236XE lobes should be ground with a 116LSA for a blower car. 114 degrees is too narrow. And the 31xx (high lift) lobes should be used as well.
Rich Krause
I have resisted posting to this thread, 'cause I have expressed my cam ideas often enough that I am sure many are tired of hearing them. But the idea that the 224/236XE cam is "small" wrt a centrifugal SC setup needs to be addressed. You can make 600+ rwhp with a smaller cam ( a la last years 214/224 in my car making 613rwhp) and not give up low end and midrange. For most setups, a larger cam will not make more hp. That's because once you max out the blower, it just aint gonna flow any more air regardless of intake duration. Very different than an NA setup, to say the least.
I would not recommend the 224/236 cam unless you are running a big blower. It won't do any good, will harm the low end and mid range, and may actually make less top end if the rest of the specs increase overlap. The 224/236XE lobes should be ground with a 116LSA for a blower car. 114 degrees is too narrow. And the 31xx (high lift) lobes should be used as well.
Rich Krause
I wish I would have went with something b/t the 234/239ish cam but i overshot with a 236/242. Now i'm going to be short shifting by 200 rpm or so
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Joined: Nov 2001
Posts: 2,985
From: In a house by the bay
Undercam, overcam smovercam.
I think alot of "street" car guys really miss a significant point where as the drag racers figured it out a long time ago.....
It doesn't matter where you choose to make your power.... 2k-5k or 5k-8k... granted more revs = more maintenance but the point is that you gear for the rpm range you make your power in! If you want torque at low revs and don't like downshifting when you decide to mash the throttle to the floor.... build an engine with a mild cam. If you want more power, then you spin the engine higher and gear so as to keep the engine in that "powerband".
The size of the cam, in my opinion, just comes down to what you can tolerate. A smaller cam, all things considered, is always easier to live with and makes for nice snappy throttle response off idle. Different strokes for different folks. I don't see any need in it getting more complicated than that though.
-Mindgame
I think alot of "street" car guys really miss a significant point where as the drag racers figured it out a long time ago.....
It doesn't matter where you choose to make your power.... 2k-5k or 5k-8k... granted more revs = more maintenance but the point is that you gear for the rpm range you make your power in! If you want torque at low revs and don't like downshifting when you decide to mash the throttle to the floor.... build an engine with a mild cam. If you want more power, then you spin the engine higher and gear so as to keep the engine in that "powerband".
The size of the cam, in my opinion, just comes down to what you can tolerate. A smaller cam, all things considered, is always easier to live with and makes for nice snappy throttle response off idle. Different strokes for different folks. I don't see any need in it getting more complicated than that though.
-Mindgame
Banned
Joined: Aug 2001
Posts: 3,505
From: looking for a flow bench so Brook and I can race
Originally posted by Mindgame
Different strokes for different folks. I don't see any need in it getting more complicated than that though.
-Mindgame
Different strokes for different folks. I don't see any need in it getting more complicated than that though.
-Mindgame
I have a strong desire to run head first into a wall.
(ps, longer strokes are better
, she told me so 
)
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Joined: Dec 1969
Posts: 10,745
From: Buffalo, New York
Maldo: you experience does not contradict my statement. It was not a whole essay on blower cams. My statement presumes a certain "correct" blower setup with the blower pullied up to produce max boost at realtively low rpm. Otherwise, you can have a blower-cam "mismatch" which will produce exactly what you describe.
All you have to do is look at a blower spec sheet. Example: Vortech S-trim has a 1000cfm maximum according to SAE standard J1723. The standard is complicated, but it specifies a number of conditions that approximate real world use of the blower. You can think of the blower, in a sense, as an "inlet restriction". This, in turn, will limit hp. Put a blower of that size on a big enough motor, making 1200+hp or more NA, and I suppose you could actually make less peak hp with the blower.
Rich Krause
All you have to do is look at a blower spec sheet. Example: Vortech S-trim has a 1000cfm maximum according to SAE standard J1723. The standard is complicated, but it specifies a number of conditions that approximate real world use of the blower. You can think of the blower, in a sense, as an "inlet restriction". This, in turn, will limit hp. Put a blower of that size on a big enough motor, making 1200+hp or more NA, and I suppose you could actually make less peak hp with the blower.
Rich Krause
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Joined: Nov 2001
Posts: 2,985
From: In a house by the bay
Trey,
I think the problem with people in general is that they don't really know what the hell they want. Either that or their expectations are just too high.
No brain surgery here.... just decide on how much power you want to make (be realistic), decide whether that level of power is going to be something you can live with on a daily basis... decide how much maintenance you're prepared to do to keep everything alive and go with it.
Keep in mind that everything should work together... the cam, converter, rpm range, gearing, everything. For what you're after (according to your other post) 425-450 rwhp... it's simple cause so many people have already "been there done that". Have fun.
-Mindgame
I think the problem with people in general is that they don't really know what the hell they want. Either that or their expectations are just too high.
No brain surgery here.... just decide on how much power you want to make (be realistic), decide whether that level of power is going to be something you can live with on a daily basis... decide how much maintenance you're prepared to do to keep everything alive and go with it.
Keep in mind that everything should work together... the cam, converter, rpm range, gearing, everything. For what you're after (according to your other post) 425-450 rwhp... it's simple cause so many people have already "been there done that". Have fun.
-Mindgame
Moderator
Joined: Dec 1969
Posts: 10,745
From: Buffalo, New York
Originally posted by Mindgame
Trey,
I think the problem with people in general is that they don't really know what the hell they want. Either that or their expectations are just too high.
No brain surgery here.... just decide on how much power you want to make (be realistic), decide whether that level of power is going to be something you can live with on a daily basis... decide how much maintenance you're prepared to do to keep everything alive and go with it.
Keep in mind that everything should work together... the cam, converter, rpm range, gearing, everything. For what you're after (according to your other post) 425-450 rwhp... it's simple cause so many people have already "been there done that". Have fun.
-Mindgame
Trey,
I think the problem with people in general is that they don't really know what the hell they want. Either that or their expectations are just too high.
No brain surgery here.... just decide on how much power you want to make (be realistic), decide whether that level of power is going to be something you can live with on a daily basis... decide how much maintenance you're prepared to do to keep everything alive and go with it.
Keep in mind that everything should work together... the cam, converter, rpm range, gearing, everything. For what you're after (according to your other post) 425-450 rwhp... it's simple cause so many people have already "been there done that". Have fun.
-Mindgame
Rich Krause