camaro87-alex

Hi there...Need some advice from people who have done this before..
I have a 87-Camaro SC with a 305 computer controlled carb on it...
Want to spice up the engine a little bit with a new cam, new intake and headers..But now it is about the cam...

Have been looking on several internett sites and there is very much to choose between...I need one cam that give my car a little more power and that acceleration is the goal here...Anyone who has a link or anything to a good performance cam for my car???...I'm no expert so please help me..
Thanks...

Sonix

iTrader: (1)

I'd skip the intake manifold. You don't gain enough power to make it worth it, dollar for dollar there are better things to do. Especially in norway, where you're paying a lot more dollars (euro's?) for each mod. Unless you want a cleaner engine bay and you just want a nice clean manifold...

Cam - The compxe256 will work great with the mods you've listed. If you think you'll ever tear into the heads and port them a bit, the compxe262 is a good choice as well. That's borderline when you want a higher stall convertor though. The 256 will still drive pretty normal, but it's got a lot (A LOT) more lift then your stock cam, and you'll feel that.

Just gotta make sure, that '87 carbed car still uses a flat tappet cam stock doesn't it? I don't think there were any roller cammed carbed 3rd gens stock.

Lunati voodoo is also a good lineup, 60101 I think is there entry level one.

camaro87-alex

Ok...thanks for the respond...You asked what kind is stock cam on my car...Concluded to my manual it stands that from 87 the engines were equipped with roller type hydraulic valve lifters...

I guess that's why I always find cam's that fits models from 55-86 or something like that

mnorton

I have this cam, and like it. Will work with the stock heads and PROM.

Cam: Crane Powermax 2032 452/465 214(270)/220(276) 112 deg., 1800 to 5800 RPM (2000 to 5500 RPM), P/N 104224 $269.95 @ summit.
Lift (1.52 rockers): 0.458"/0.471"
Lift (1.6 rockers): 0.482"/0.496"
Duration @ 50: 214/220
LSA: 112 degrees

camaro87-alex

Ok...thanks...Yeah i guess I will shop from Summit or something since they ship international...I don't have a PROM by the way..no TPI

Do you know how much more HP or torque you got with only that cam??

I was planning to by a new intake manifold also, but sonix said that it would be just waste of money??...Wouldn't I at least get a little more power or better mpg's or something???

Sonix

iTrader: (1)

The suggested aftermarket intake for you would be the Edelbrock performer manifold. Since you have a 3rd gen, you should have an aluminum intake manifold stock, not like the old '70s cars that had cast iron ones.
Your stock manifold is almost identical to the Edelbrock performer, except it'll have 20yrs of dirt on it.
The step up, the Performer RPM is a nice one, but you may lose a bit of torque.
What i'm saying is that you'll get a very minimal gain, and for $150-$200 it's not worth what gains you get. There are better things you can do that'll give more HP/$ right now.

Hmm, I didn't know the carbed cars has roller cams, but I did know that after '87 just about everything went roller. I'd want to be fairly sure before you bought a new cam though.

That roller cam suggested is a tad bit more aggressive than i'd pick, if it were me. But your call.

camaro87-alex

Ok...thanks again for the tips...I am really no expert...But I have been looking on some Build up sites on 305engines the way they explained it you could get more power from an intake AND a cam...but I'm listening to you cause I need to save what I can on money
Here is a link to the page if you are interested:
http://www.goingfaster.com/spo/325_h...chevrolet.html

But could you explain to me something Sonix...I want to know more about Camshafts...So I need to know the basics about what is the meaning of:
Duration at 050inch??...What is the difference about 218/224 and 220/224??

And that with the valve lift..I know what it means but what does it do...
Is it better or worse (may not be the right word) with lower exhaust lift than intake lift???...Or the opposite???

And what is the difference between example: 0.576int/0.570exh and 0.384int/0.407exh......

Please try to explain me something here...

Stekman

I'm not Sonix, so you may ignore me. In a nutshell: Duration is a measurement, in degrees of crankhshaft duration, that the valve is opened. Advertised and .050" are the 2 most common durations listed on cam spec sheets. Advertised is pretty much from the very beginning when the lifter first engages the opening ramp to the point where it pretty much leaves the closing ramp. Generally speaking .006" lift +/- depending on which cam company you deal with. .050" duration is measured from the point where the valve is opened .050", both opening and closing.

The difference in the 2 specs you listed are the intake lobes. The second cam has a slightly more aggressive intake lobe.

The difference between the lift figures is the first number is the lift at the valve, the other (smaller number) is the lift off the cam lobe. The cam lobe moves the lifter .x" distance. In your example, the lifter goes up .384" in the lifter bore. However, the rocker arm is a multiplier (rocker ratio). Factory ratio being close to 1.5, multiplies the cam lift by 1.5 to get .576". Same for the exhaust.

On modified engines, with good cylinder heads and free flowing exhaust systems, there's a benefit to running a larger intake lobe (more lift/duration) than the exhaust as it will allow you to cram more air in there. On stock or even midly modified engines, the exhaust side needs all the help it can get, thus why most of the off the shelf grinds you see grind the cams with larger exhaust lobe profiles.

camaro87-alex

Ok...So what effect does the lifter have if it goes higher up than listed above??...Let say you have a cam that has 0.384int...
What effects has a cam that has 0,576int...on the engine??...more hp?..less hp??..more acceleration??...less acceleration...more torque??...i know I sound stupid but it is even harder for me to understand since I am a Norwegian guy..

Stekman

On an engine that has 1.5 rocker ratios, .384" lobe lift and .576" valve lift are the exact same thing.

mnorton

The Crane 2032 that I recommended, does have Duration numbers that are the max that I would go with on a 305 roller engine. A little more Lift (if you had heads that would allow it) would be fine though.

Hgh "Duration" numbers build power at higher RPM's, at the sacrafice of power at lower RPM's.


A little more info for you:

These type cams are what are sometimes reffered to as "Split Pattern" cams. Meaning the intake and exhaust lifts and durations are not identical. The reason for that (as touched on by Stekman) is that the exhaust valve is smaller than the intake valve, so more lift and duration on the exhaust lobe helps to improve exhaust flow.

The other spec to keep in mind is called LSA, Lobe Separation Angle. It's basically a measurement that indicates the valve overlap, meaning the period in which both the intake and exhaust valves are open (or near to being open) at the same time. In a nutshell lower LSA's are higher performance cams, but Idle poorly, and provide less manifold vacuum to run things like power brakes etc.

Sonix

iTrader: (1)

I'll attach my sig, i've got a cam info article at the bottom, it's got a quick writeup that'll explain some terminology.

The way I like to think of it is this;

duration @.050 sets your powerband. Larger number means it'll be higher in the RPM range. 210/210 is going to be low, almost like stock, 1000-5000RPM. 230/230 is much higher, 2400-6000 say.
The higher your power band is, the more power it'll make, due to the fact that an engine is a glorified air pump, more air = more power. Higher RPM gives more power hits per time, so you get more power.

But you want that powerband to correspond to what you'll be using, so a stock car that's driven on the street, 1000-5000RPM is great.

Advertised - as mentioned, that's the duration at .006" or .004" (depending no who grinds the cam). You can't compare these across companies, since they measure at different lifts. Advertised - duration @.050 gives "hydraulic intensity", ie, how fast the ramp rates are. Longer number means slower. It'll have the big cam drawbacks with none of the big cam power. Faster is better, but harder on valve train.

Lift is the same way, the more lift you have the more power it'll make, period. More lift at the same duration gives more power. Two cams with similar duration - the one with more lift makes more power. It has to be a more aggressive grind to do this though. Another reason to buy a good aggressive modern grind.

Last point - when a company, lets say comp cams, says that the recommend RPM range is 1200-5200RPM, that's usually spec'ed for the most common engine. So when it's an SBC cam, they're talking about a 350. The bigger the engine, (with same valve size), the more cam it'll need. So, a 305 is smaller, so it makes that cam feel bigger. So that cam would be more like 1500-5500RPM in a 305, for example. Another reason to choose a smaller cam, since it's in a 305.

camaro87-alex

Thanks guys for the explaining articles above...This really helps me a lot to understand what to look for...But still there are so many different cam's to choose between so mayby you could help me a little bit there...I have a computer controlled carb also so I need a cam that is designed for that..And I also have Hydraulic roller valve lifts as written above so I need a cam that is compined to that..

Anyone that can help me mayby on Summit??
Here is a link to a couple of cams I've been looking at..What do you think??
http://store.summitracing.com/partde...5&autoview=sku

http://store.summitracing.com/partde...8&autoview=sku

http://store.summitracing.com/partde...1&autoview=sku

Just some examples...Please help me to choose...If anyone of you mayby know a better choise on my stock 305 engine please respond..

Thanks...

mnorton

As to the links that you've posted:

1.) Good - Similar to a stock cam but better.

2.) Better - Higher lift than stock heads will allow for, but good with after market heads or modified stock heads.

3.) Bad - 106 LSA, too low Duration, look at the RPM range.

camaro87-alex

Ok...I think I have found a perfect cam for my stock 305...
http://store.summitracing.com/partde...8&autoview=sku

I think that one above should be ok...Since I have stock heads also...
Has a operating range of 1200RPM-5200RPM....
Also has a duration @.050 of 210int/218exh

Would this be a ok choise you think???
I need as much advice a possible since it is the first time I am buying a cam

Stekman

Good cam, except for the lift. On factory un-modified heads, the bottom of the retainer can slam into the top of the guideboss/valve seal at around .480" valve lift. That cam you posted is well above that. i.e. That cam will not work unless you have the heads modified for more lift (milling the guide bosses).

Also, have you verified yet whether you have a flat tappet or roller cam?

camaro87-alex

Ok...Have to find another one then...And i do have Roller cam...they begin with roller typed cam's in 87..

sofakingdom

iTrader: (1)

I would strongly advise AGAINST trying to get the maximum possible cam that exists, in that case.

Look at this one instead. http://store.summitracing.com/partde...2D08%2D501%2D8

You WILL need to upgrade your valve springs, retainers, keepers, and valve guide seals. Follow the cam mfr's recommendations.

Your 87 should have a roller cam; in which case, it will use the Comp part numbers that start with 08-. Like the one I posted: 08-501-8. The one you posted starts with 12-, which means it's for the pre-roller (86 and earlier) motors. It might be a good idea to LOOK and determine FOR CERTAIN which one you have before ordering anything. If you have a non-roller block, and/or non-roller lifters, then you MUST use a 12- cam, and then if you want a roller cam, you MUST also buy the "retro-fit" lifters and different push rods, which will cost several hundred dollars on top of the cam, springs, and so forth. If you have the whole factory roller setup in your engine, then you can re-use your factory lifters.

If you don't have the factory roller stuff, and upgrading to a roller is not important enough to spend THAT MUCH money, then look at this cam here. http://store.summitracing.com/partde...2D12%2D234%2D2 With, of course, the new springs, retainers, keepers, and valve guide seals.

camaro87-alex

How about this one??
http://store.summitracing.com/partde...5&autoview=sku

camaro87-alex

One thing I am sure about is that my engine is 100% factory stock and it is from 87 and combining to the history of all 87 camaros they started with roller type cams that year..In other words I have a stock 305 COMPUTER CONTROLLED CARB engine, with a roller cam on it.....That second cam you have linked to sofakingdom, is an ok cam for me but it is not compatible with computer controlled engine's and then I guess I will have a problem or what???

sofakingdom

iTrader: (1)

It will work fine with computer controls.

I'm driving a computer-controlled carb 305 around with that exact cam in it, and I have been for several years; works great. I don't know why they say it's "not compatible".

Maybe I'm an idiot (well, forget about "maybe", I am); but I don't trust "history" or any of that. When it comes to buying parts, I ALWAYS LOOK FIRST. That saves me a certain amount of grief and shipping wrong stuff back and forth. I've been surprised more than once.... like, for instance, a few months ago when one of my little brothers and I tore down the 305 with computer controlled carb in his 87 Monte Carlo, and found NON-ROLLER stuff inside it. We felt REAL STUPID standing there right then, holding a roller cam we'd already bought for it because he was SURE his 87 would have a roller.

camaro87-alex

hehehe...lol....So you are driving around with that roller cam or that flat tapped cam???....I guess you were pissed off when you've bought a new roller cam for your monte carlo then??...I agree to you about have a look first...But it is just that my manual also said that if i have a 87 Engine I have this roller cam...So I think I will stay on to that one...But what you are saying is that it isn't any problem with the computed controlled carb system on cam's that is not compatible with it??...hmmm...Sounds a little bit strange to me...I don't think you are the only one who can call yourself a idiot...I think i am at a hiigh idiot range myself

naf

iTrader: (7)

Your computer controlled q-jet should have no problems with that cam. It's about the simplest computer controlled induction system out there and will adapt to it easily. Some cams with less overlap (that one has 112 degrees) will cause problems with the O2 sensor readings at lower RPMs.

Always check for roller lifters before buying. All you have to do is pull one of the pushrods out-remove a valve cover, loosen one rocker...roller lifters are taller and use a shorter than standard length (7.8") pushrods. Maybe 7.2? Someone will have to chime in I can't remember and I'm too lazy to look it up. Chances are that if one of the lifters is a roller then the rest are too.

Stekman

7.800" for flat tappet, 7.2" (IIRC) for roller. If you have a pretty good little flashlight, you can just pop a valve cover and look down one of the oil drain back holes, between the pushrod slots. If you see factory roller equipment down there - the dogbones, leg of the retainer spider - then you have factory roller.

mnorton

That one will work. It's the 2031. I have the 2032 in my 305.

Sonix

iTrader: (1)

Yea, reason I suggested looking to make sure you've got roller stuff in there (and thankfully most people agreeing) is that GM does some weird things. Some parts get left over from past years and get used in the later year. It's actually quite common. '87 is the transition year, most carbs were phased out, as were the flat tappet stuff. It sucks having to have something reshipped, it sucks worse when it's oversees and its your dime... err, euro, whatever.
So yea, pop off a valve cover, pull a rocker and lift out a pushrod. Measure it with a ruler, that should be close enough to find out "almost 7 1/4" or "a bit more than 7 3/4" sorta thing.
Then buy your cam.

Comp xe264hr for roller, or compxe256 for flat tappet. You really have a love for crane stuff eh? That 2031 you listed is very close to the xe264hr, so it'd work great.

camaro87-alex

Agian guys i will say thanks for all the good answers here..I really appreciate the help I am getting here..Actually I have learned a LOT in this article...Today I'm going to check if I've got roller cam or flat tapped cam...
I talked to a friend that has been a car mechanic here in Norway and he said that if I pop the valve cover I will see it on the top of the valves...Is that true??...If not I can measure it with a ruler like you said...Just pull down a rocker you said yeah??...And then lift out a pushrod??...hmm..Like I said...first time I'm doing this stuff on my own but I've gotta try..
I'm not sure what kind of cam I will choose yet even if I have roller cam...
I am not familiar with either COMP cams or Crane...But what I know is that almost every tuning factory here in Norway use COMP cam's so mayby I will go for that..In other words I am at your side Sonix...

camaro87-alex

Now I have finally found out what kind of cam I have
I took out one pushrod and measured it and the length of it was 182mm
That is about 7.2" like Stekman wrote...Thanks for giving me this tips...
I totally agree to you guys that it is better to be sure or not sure

So now I can buy a cam, roller cam like I was planning to do.
But I don't need new lifters right???...Cause I need to do this as cheap as possible...Money is no good ....

Guess I will go for the COMP cam then...If it's no problem with the computer controlls??...

mnorton

You can re-use roller lifters.

Sonix

iTrader: (1)

Yea, your buddy said you can look on top of the valve, that's to check if you have roller ROCKERS. If it's stock, you won't have that. Not that that fact really matters either way.

The comp xr264hr as linked above is good. You can keep your stock roller lifters which keeps costs low, but you will need new springs, might as well get retainers and locks (locks are also known as keepers), and positive valve seals.

camaro87-alex

Ok...Then i think I will choose that one....When it comes to the springs and retainers, locks and valve seals I found a package on Summit...
But wooooow....What a price...630bucks??....A little to much I think but if there is no other options I just have to buy it...
Here's the link:
http://store.summitracing.com/partde...5&autoview=sku

Sonix

iTrader: (1)

No no, that's all high end titanium stuff, you don't need that.
Some comp 981 springs, $80. The recommended basic steel retainers and
locks, ~$50. And the cam, $240 or whatever it was.

camaro87-alex

OK....then i will go for that "kit"...Do you have any idea what this thing would do to my HP and Torque??...Compared to other tests people have made with a cam I can get up to 50HP more??...I think that is a lot but I don't have so much experience I could answer that...What do you think??

camaro87-alex

Then I will go for this Cam and Springs

The Cam: http://store.summitracing.com/partde...8&autoview=sku

The Springs Kit:http://store.summitracing.com/partde...5&autoview=sku

Sounds ok Sonix????

sofakingdom

iTrader: (1)

You would do better with these. Unfortunately, they don't come as a "kit", you will need to order each thing separately.

Springs
Retainers
Keepers
Seals
Shims

You'll need some one of the various types of spring compressor that works when the heads are installed; and some method of measuring the installed height of the springs. You'll want to add shims under each spring such that the distance from the top of the shims to the bottom of the outside edge of the retainer is as close as possible to 1.700" (43.2mm).