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Discussion Starter · #1 ·
The venerable HOT CAM. The most popular LT1 Cam in existance. BUT not the optimum for the heavy B-Body Cars. Other cams such as the ZZ3, 227 and 845 are other good choices.

BUT which is considered the "NEW" BEST Street Cam today? Especially considering the new designs that have come out in the last year or so. I want to focus on Street Cam. IMHO the 847 in a 350 is not a good Street Cam.

Just looking for your opinion as which cam is considered the Best Street Cam for our B-Body?
 
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Discussion Starter · #2 ·
The question is WAY too broad to answer. The cam choice would be affected by almost everything, head flow and type (iron/aluminum, stock/screw-in studs, machine work done to them), gears, converter, header type and primary size, static engine compression ratio, expected rpm range, expected valve train life and even the car weight.

IMO, the hotcam is a better street cam while the 845/227 cams are better for 1/4 mile runs. Hotcam makes more hp and easier on the valve train. Also, you can use 1.6 rockers with stock heads all around and it makes the maximum lift perfect for stock iron heads.
 
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Discussion Starter · #3 ·
Dan, I gotta agree with Dmitry. This is a VERY BROAD question. There is no "best cam" but there is the best cam for you
I'd bet that the best cam for you isn't an off-the-shelf grind.
 
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Discussion Starter · #4 ·
I vote for the Stock cam. ;)

Plenty of low end torque, good mid range, and can get your car into the 12's if you turn it into a chicken bucket. :D
 
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Discussion Starter · #5 ·
well it depends on your setup.. 2500 stall and a gear then a hotcam will feel GREAT and not be too big.

Low stall and even stock gear... Comp 304 or a stock cam... gobs of torque and fun to drive.Havent ever ever been impressed with the zz3 or similar cams.

Hotcam IMHO in driving MANY impalas with cams... is the best feeling and has the best sound to it while still being able to pass emissions on a good tune.

Remember GM engineers Specd the Hotcam. They know their stuff. People like to down the hotcam but it is just a great performar and well tuned can make 350 HP at the wheels very driveable.
 
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Discussion Starter · #6 ·
Originally posted by ÃÐïا§:
Dan, I gotta agree with Dmitry. This is a VERY BROAD question. There is no "best cam" but there is the best cam for you
I'd bet that the best cam for you isn't an off-the-shelf grind.
Well guys it is a subjective question. BUT the Key is STREET CAM meaning Drivability for the Street with more performance then the Stock Cam and still pass Emmission.

Some people are delighted with the ZZ3 other with the Hot Cam. But I hinting about the newer Cams developed for our LT1 such as the ones with a 113 LCA.

Given a choice from your past experience. Which of the cams have given the best balance in performance for the Street.

Lets add NO Porting to the equation.
 
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Discussion Starter · #7 ·
XE and XFI cams have steeper lobes and therefore make more midrange power. However, they require better than average valvetrain and compromise high rpm power. If you're planning to keep stock iron heads (pressed studs, single springs), aluminum rockers and stock-like pushrods, cams with steep lobes is not that good of an idea, imo. Smaller cams like XE501 will work though.

Cams with a high LCA/LSA usually have a wider power range but compromise torque throughout the powerband.

Crane 227 with 1.5 rockers or HotCam with 1.6 rockers would be my choice depending on how high you want to rev the engine. Stock cam can work well also.
 
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Discussion Starter · #8 ·
Originally posted by Spartus.:
I vote for the Stock cam.
And I thought I'd be the only one saying that. I agree.

With some porting to the heads, and modified intake & exhaust, 1.6 rockers, plus gears (or gears +T56) you get all the stock driveability and part throttle fuel economy you would ever want or need..... and the potential to get somewhere in the 14s, or less, possibly MUCH less depending on the rest of the car mods.
 
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Discussion Starter · #9 ·
Originally posted by kdrolt:
</font><blockquote>quote:</font><hr />Originally posted by Spartus.:
I vote for the Stock cam.
And I thought I'd be the only one saying that. I agree.

With some porting to the heads, and modified intake & exhaust, 1.6 rockers, plus gears (or gears +T56) you get all the stock driveability and part throttle fuel economy you would ever want or need..... and the potential to get somewhere in the 14s, or less, possibly MUCH less depending on the rest of the car mods.
</font>[/QUOTE]Ken, man where have you been? There are more than a few of us in the 12s with stock heads and cam now :D Heck, I did it without even pulling the stock 160k mile valvesprings and rocker off the car
 
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Discussion Starter · #10 ·
Originally posted by kdrolt:
</font><blockquote>quote:</font><hr />Originally posted by Spartus.:
I vote for the Stock cam.
And I thought I'd be the only one saying that. I agree.

With some porting to the heads, and modified intake & exhaust, 1.6 rockers, plus gears (or gears +T56) you get all the stock driveability and part throttle fuel economy you would ever want or need..... and the potential to get somewhere in the 14s, or less, possibly MUCH less depending on the rest of the car mods.
</font>[/QUOTE]You have dyno/track numbers to back that up? The only reports of ported or aftermarket heads with a stock b-body cam I have seen have been raging disappointments, like one guy LOSING 2 hp even while upping compression and another making less power with a similar setup to my small cammed car. The later was 250rwhp with AFRs smaller heads 195s I believe through stock exhaust manifolds
. The "do the heads first" mentality is a leftover from the 80s when heads sucked, the LT1 heads are better than all that came before for production smallblock Chevys and even better than some of the aftermarket and race stuff, meaning the cam is the new choke.

AFR 195s with stock cam I gave it too much credit it was 243rwhp where my ZZ3 cammed motor made 263rwhp, I usually round it to 260 though but I have the charts if you want.
Here is where Karl of all people speaks about losing power with ported aluminums. Think most of us will agree that man knows how to make power and go fast look at the ET page for proof.
 
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Discussion Starter · #11 ·
Originally posted by 96capriceMGR:
</font><blockquote>quote:</font><hr />Originally posted by kdrolt:
</font><blockquote>quote:</font><hr />Originally posted by Spartus.:
I vote for the Stock cam.
And I thought I'd be the only one saying that. I agree.

With some porting to the heads, and modified intake & exhaust, 1.6 rockers, plus gears (or gears +T56) you get all the stock driveability and part throttle fuel economy you would ever want or need..... and the potential to get somewhere in the 14s, or less, possibly MUCH less depending on the rest of the car mods.
</font>[/QUOTE]You have dyno/track numbers to back that up? The only reports of ported or aftermarket heads with a stock b-body cam I have seen have been raging disappointments, like one guy LOSING 2 hp even while upping compression and another making less power with a similar setup to my small cammed car. The later was 250rwhp with AFRs smaller heads 195s I believe through stock exhaust manifolds
. The "do the heads first" mentality is a leftover from the 80s when heads sucked, the LT1 heads are better than all that came before for production smallblock Chevys and even better than some of the aftermarket and race stuff, meaning the cam is the new choke.

AFR 195s with stock cam I gave it too much credit it was 243rwhp where my ZZ3 cammed motor made 263rwhp, I usually round it to 260 though but I have the charts if you want.
Here is where Karl of all people speaks about losing power with ported aluminums. Think most of us will agree that man knows how to make power and go fast look at the ET page for proof.
</font>[/QUOTE]At the Poconos my car dynoed at 252hp and 298TQ
The engine has TriY, 1.6rr, 52mm Bored TB, Delteq.
Based on earlier comment it looks like the ZZ3 Cam is about 20ph across the board over the Stock Cam with 1.6's.
 
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Discussion Starter · #12 ·
Originally posted by kdrolt:
</font><blockquote>quote:</font><hr />Originally posted by Spartus.:
I vote for the Stock cam.
And I thought I'd be the only one saying that. I agree.

With some porting to the heads, and modified intake & exhaust, 1.6 rockers, plus gears (or gears +T56) you get all the stock driveability and part throttle fuel economy you would ever want or need..... and the potential to get somewhere in the 14s, or less, possibly MUCH less depending on the rest of the car mods.
</font>[/QUOTE]Stock 173k mile cam here.
286hp/335tq
33mpg best tank
T56 & 4.10's
14.1 @ 95? (don't remember the trap speed)

My stock cam hasn't let me down, yet. No new rockers or even springs! :cool:

Randy
 
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Discussion Starter · #13 ·
FWIW, my "maxed out" STOCK CAM motor made 309 RWHP and 354 RWTQ. Mods were :</font>
  • Comp Pro Mag 1.6 RRs</font>
  • 26915 Beehive Valvesprings : HIGHLY recommend these....not cheap, but they really do work better than most of what else is out there. DON'T cheap out on the valvesprings, you are THROWING AWAY HP by doing so! Car revved all the way to 6200 without a hint of valve float and pulling all the way....remember, STOCK cam!</font>
  • Team SS intake, F-body MAF, 58mm AS&M TB (which I bought for the stroker motor....convinced the HP was NOT in the TB)</font>
  • Tri-Y headers with exhaust cutouts (open), no cats</font>
  • 2.5" crappy Edelbrock exhaust, but the cutouts were open ;)</font>
  • Bryan Herter OBD-I conversion, his FIRST guess at the mail-order tune (i.e. we never even "tweaked" it!)</font>
  • 160 T-stat</font>
  • T-56 with LT1 flywheel, LT4 clutch, 3.73 gears (I'm an autocrosser, not a drag racer ;) )</font>
  • Meziere HD Water Pump</font>
  • MBA Underdrive crank pulley with overdrive alternator (i.e. only the PS pump was slowing down)</font>
  • Stock 115K mile motor, heads never off, stock intake manifold, stock injectors, etc.</font>
Needless to say, drivability and MPG were pretty good for the above since it was still the stock cam ;)
 
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Discussion Starter · #14 ·
Yeah I only made 263 at 5400 with the ZZ3 cam 1.5s, sewerpipe, 87 octane BH mailorder tune, stock MAF, stock maifolds and cats to Dynomax catback. With the ZZ3 cams low intake lift there should definetely be more power in 1.6s on that side. The manifolds and cats undoubtedly hurt a lot. I didn't setup the tune right so we had a hard time avoiding downshifts but managed 284 TQ at 4100 and falling already no idea what peak really was. This was with SS wheels and rubber a steel driveshaft, 2800 stall Edge no fan in front of the car so they were basically worst case numbers and were on a Superflow which like a Mustang is supposed to register lower than a Dynojet. Going in with stock manifolds and cats I knew my numbers would be lower than many see with stock engines. I should see if I can get her strapped down next week with the RAISS, f-maf, and CIA budgets being the main mods since. Ed's numbers look damn good just consider the T56 is helping them be better than an A4 car would register with the same flywheel power.
While yes I swapped cam I will say the stock cam is given far too little credit, it may be "small" but the performance guys get with it speaks to it having been superbly matched to this car.
 
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Discussion Starter · #15 ·
1/4 mile performance does not mean everything. My car only ran about 0.3 sec (considering 60' and temperature/humidity differences during the best run) after a heads/cam swap ([email protected], 1.73 60' VS [email protected], 2.05 60').

However, there was a huge difference in dyno numbers (361 rwhp vs 279 rwhp) and highway performance.
 
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Discussion Starter · #16 ·
Originally posted by 96capriceMGR:
...You have dyno/track numbers to back that up? The only reports of ported or aftermarket heads with a stock b-body cam I have seen have been raging disappointments, like one guy LOSING 2 hp even while upping compression and another making less power with a similar setup to my small cammed car. The later was 250rwhp with AFRs smaller heads 195s I believe through stock exhaust manifolds
. The "do the heads first" mentality is a leftover from the 80s when heads sucked, the LT1 heads are better than all that came before for production smallblock Chevys and even better than some of the aftermarket and race stuff, meaning the cam is the new choke.

AFR 195s with stock cam I gave it too much credit it was 243rwhp where my ZZ3 cammed motor made 263rwhp, I usually round it to 260 though but I have the charts if you want.
Here is where Karl of all people speaks about losing power with ported aluminums. Think most of us will agree that man knows how to make power and go fast look at the ET page for proof. [/QB]
A long quote but I needed it.

AFR 195s would be a poor choice with a stock cammed 350. The 180s would have been ideal for overall use & performance... except that the AFRs are an expense that I would have never turned to if I was going to keep the stock cam. IMO it's questionable for a number of reasons that you should be able to figure out, especially using 195 cc intake runners with the stock cam in a 350. Lighter weight heads can be had by the aluminum LT1s, so there isn't much reason to use any AFR head in my cheap world of armchair performance, kid rearing & mortgage paying.

Next point: Stock cammed Bcar LT1s make 210-220 rwhp, not 240-250. So if you alter the heads & exhaust without changing the cam, and make more power (like 30+), then it shows that the cork was something other than the cam. Translated, it means that the stock cam is good for a lot more IF the engine can be allowed to breath. It's Lingenfelter 101, and a concept used by most high end manufacturers that use small-runner high-flow heads: they don't need a lot of cam to make a lot of power. So to suggest it's an outdated practice (looking to the heads + exhaust before touching the cam) means you jumped to a conclusion without looking at the entire question.

Aside: I already know about the deficiencies in the sbc heads from the 80s and exactly what the improvements were in the LT1 series that were an outgrowth of the Bowtie Phase 6 head, and those that preceded it. I did know that earlier heads, ahem, sucked. Thanks for the reminder.

As far as disappointments go --- you also have to define your metric. I like stock driveability, I like optimum fuel economy in a car that I use for a daily driver, and I like reliability. If that means I only get into the 14s (3.08 rear end Cheston) and not break the 4L60E -- then I'm satisfied. I can count the times I've raced on the drag strip on one hand (shocking, I know) --- of course I can also count the number of times I've destroyed an engine or trans also on one hand (zero). The miser in me would love to see someone use the T56 with a stock cammed engine with exhaust and head porting -- just to see if the highway fuel economy could be put into a truly obscene range like 30+ mpg. But that will probably never happen, especially here.

FWIW I know Karl knows how to make power, and he knows that I know the how & why it happens. His post proved my point. And to make a lot more power you need more than the stock cam. That wasn't the question asked. The question was: what was the best street cam? It's ok for you to have a different answer than me, because your needs are different than mine.

ÃÐïا§: I've been here, so yes I knew about the transgressions made to get into the 12s with the factory cam (I read the Fast times web page too). I didn't want to carry that torch -- especially when it seems that my suggestion of getting into the 14s was so controversial.
 
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Discussion Starter · #17 ·
Next point: Stock cammed Bcar LT1s make 210-220 rwhp, not 240-250. So if you alter the heads & exhaust without changing the cam, and make more power (like 30+), then it shows that the cork was something other than the cam. Translated, it means that the stock cam is good for a lot more IF the engine can be allowed to breath. It's Lingenfelter 101, and a concept used by most high end manufacturers that use small-runner high-flow heads: they don't need a lot of cam to make a lot of power. So to suggest it's an outdated practice (looking to the heads + exhaust before touching the cam) means you jumped to a conclusion without looking at the entire question.
Did you miss Ed's post about over 300 at the wheels 240-250 with boltons is NORMAL, 220 is BONE STOCK, hell first base being replaced with s sewerpipe is accepted as 9rwhp alone. As for drivability you can go signifiganly bigger than stock without compromise my cam is 18 degrees bigger on the intake side was fine towing a fishing boat with 2.93s and a 1650 stall. Only now with the headers is the cam audible, with the stock manifolds and cats only a very few gearheads could pick out the sound of it. Milage between both my cars is quite comparable before the headers and now the Caprice seems to be getting better milage with them.
I agree the stock cam is not given enough credit and I could be faster now had I spent that money on something else, I would just like to see some measuable data that ported heads on a stock cam is worthwhile because the data I have seen sofar shows otherwise. Even before and after MAF GPS would be a solid indicator.
 
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Discussion Starter · #18 ·
96capriceMGR writes:

Did you miss Ed's post about over 300 at the wheels
No. Though I did confuse Karl with Ed (Autocrosser) when I previously said that his post made my point.

...As for drivability you can go signifiganly bigger than stock without compromise my cam is 18 degrees bigger on the intake side was fine towing a fishing boat with 2.93s and a 1650 stall.
The stock cam obtains excellent part throttle torque and fuel economy because it is a short duration cam with minimal overlap. It extracts the most energy it can from combustion because it opens the exhaust valve late. A "mileage" cam is usually considered counterproductive when it comes to making power and that's one of the reasons. The reason why the Bcar LT1 does so well at all things is because the heads flow so well, because it has a decent factory dual exhaust, and because it uses a very mild cam.

The cam can obviously be swapped for just about any other cam, and it will make more power & torque, as proven by many here. And it will also result in a decrease in fuel economy, and an increase in emissions (however slight, and hopefully still emissions compliant). The economy loss is sometimes offset by a reduction in frictional losses in the drivetrain, but it's not a stretch to think that a cam swap usually decreases fuel economy either directly in the engine or by the owner's foot. If that weren't the case, GM would have used a bigger cam and gotten better CAFE during engineering...

So the point is that you can still make excellent torque and power with the stock cam, and give up zero part throtle driveability & economy, provided you do other things to the engine + exhaust (as I already said). That's what makes the stock cam, IMO, the best street cam (the original question in the thread).

IIRC you complained about track & dyno numbers to support what I claimed. Hasn't there been enough proof by now?

Only now with the headers is the cam audible, with the stock manifolds and cats only a very few gearheads could pick out the sound of it. Milage between both my cars is quite comparable before the headers and now the Caprice seems to be getting better milage with them.
Headers + exhuast mod decrease the pressure in the exhaust so that decreases the resistance to (A) blowdown at EVO and (B) exhaust pumping after the cylinder pressure equals the header/manifold pressure. Both make the engine more efficient so greater fuel economy results, and that partly offsets what you lost during your cam swap. You also made the engine louder at WOT, in a manner that the factory isn't likely to do.... and opening up the exhaust is not a cam swap so it has little bearing here.

I agree the stock cam is not given enough credit and I could be faster now had I spent that money on something else, I would just like to see some measuable data that ported heads on a stock cam is worthwhile because the data I have seen sofar shows otherwise. Even before and after MAF GPS would be a solid indicator. [/QB]
Big port heads (AFR 195, LT4) are dogs on a 350 that doesn't go above 6000 rpm, and especially so in a heavy car, and even more especially so in one with a stock cam. The velocity in the intake port gets lazy so the air:fuel mixes poorly after the injector and doesn't burn well. That means, in turn, that the factory ignition timing isn't optimum anymore and so the engine won'take optimum power. MAF data tells you about airflow, but it tells you zero about optimal combustion. And fast burn heads are only fast-burn if the air:fuel mixes well as it enters the cylinder. That's why the LT4 heads, and the conventional-flow-cooled (cloned) versions of the LT4 head (called the Fast Burn head) are not good choices on anything but a high rev engine, or a stroker engine, or both. And that's also why the AFR 195s were disappointing on a stock cammed LT1 350, IMO. They'll run ok, but arguably no better than a ported iron LT1 head.... unless you run big cubes or hgigh rpms or both.

You almost can't make a mistake with small runner LT1 heads that have been mildly ported (but still small runner), no matter what cam you run with them and especially with the factory cam.
 
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Discussion Starter · #19 ·
Originally posted by kdrolt:
The miser in me would love to see someone use the T56 with a stock cammed engine with exhaust and head porting -- just to see if the highway fuel economy could be put into a truly obscene range like 30+ mpg. But that will probably never happen, especially here.
You sound like you doubt me Ken...I got 26 MPG REGULARLY out of my old car before the HOT cam...and 25 mpg with the cam and 4.10's. That car also trapped 97 mph with stock EVERYTHING other than the T56 and S&B (same as a K&N really) filter...then went 103 with the addition of the cam, valvesprings, roller rockers, catback exhaust and injectors...same filter, same stock screened MAF, same TB, same stock exhaust manifolds and cats, same stock heads and stock intake manifold.

I do have a much "bigger" plan and buildup in the works for the new car, but I am starting with the T56, and I have the heads off the old car (still bone stock and still bolted to the block to clean up a little)...and it's already got an exhaust on it. I think I can be persuaded to at the very least give it a shot for the fall/winter/spring until I have everything together for the other setup.

I personally would like to see if I can achieve 30+ mpg with the stock cam and then slide the HOT cam from the other car in just for the fun of it to see if I can still achieve 30 mpg...I never did do ANYTHING to the TB, heads, intake or exhaust manifolds/cats on the other car (though after Batman's lessons I did spend a lot of time tuning the snot out of that thing). Send me an e-mail when you get a chance.
 
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Discussion Starter · #20 ·
Originally posted by Mike454SS:
You sound like you doubt me Ken...
Nonsense, of course I believed you. Your engine was probably very tight and the EGR was probably working properly. I also know how heavy your foot is --- so I wonder what kind of mpg you would have had driving, ahem, more conservatively.

...

I personally would like to see if I can achieve 30+ mpg with the stock cam and then slide the HOT cam from the other car in just for the fun of it to see if I can still achieve 30 mpg...I never did do ANYTHING to the TB, heads, intake or exhaust manifolds/cats on the other car (though after Batman's lessons I did spend a lot of time tuning the snot out of that thing). Send me an e-mail when you get a chance.
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