The stock 3.4L Cam has the following features:
Lobe Lift:
Intake = .2626" with 1.5 ratio rocker arms = .3939"
Exhaust = .2732" with 1.5 ratio rocker arms = .4098"
Install valve spring height = 1.610"

Stock 2.8L Cam
Lobe Lift:
Intake = .2626" with 1.5 ratio rocker arms = .3939"
Exhaust = .2732" with 1.5 ratio rocker arms = .4098"
Install valve spring height = 1.575"

Reference:
1993 Camaro Service Manual
Page 6A2B-55
3.4L V-6 VIN CODE S

Conclusion:
The stock 2.8L cam valve lift is the same as the 3.4L cam. All this time we thought that the 3.4L cam is more economy cam and one step down from the 2.8 cam, but it turns out to be the exact same lift as our 2.8L cam.

Any comments?

Interesting.
It would be cool if someone had access to the Camaro equivalent to the 22P parts catalog, and looked up the GM part number for the cam.
Even better would be if someone had a Camaro cam laying around and wrote down the numbers.

Oreif (I think) posted a chart, a while back, that spells out all of the lobe and valve lifts for various V-6 60 cams. It listed the Fiero engine by RPO (L44) and I believe it listed the Camaro engine, as well. Going from memory (I'm at work. the chart is at home.) the specs were definitely different.

I sure would like to get to the bottom of this.

I'm certainly not meaning to imply that your info is incorrect, but the Helm / Fiero service manual states that our exhaust manifolds are "cast nodular iron". Coulda fooled me.

------------------
Raydar
88 3.4 coupe...........

Coming soon...
88 Formula, presently under the knife.
Read Nealz Nuze!

[This message has been edited by Raydar (edited 08-22-2004).]

All I know is the engine I have is out of a 1994 Firebird with 44K miles on it.
The cam was measured for lift and was stamped with grind # 3040
Which according to GM the cam is .386/.387 lifts and 240/248 duration.
The Fiero cam is stamped with grind # 3002 which is .394/.410 and 258/265 duration.

Each cam is stamped with the grind number.
If anyone is building a 3.4L and you know what year/make the engine came from, please post the grind number.
It is located on the trans side of the cam. It should be a 3XXX number. You can pop off the read thrust cover and read the numbers as well.

[This message has been edited by Oreif (edited 08-23-2004).]

I have one in my hands now, it reads as follows:
323B
D5
CWC

Orief, what does all this mean?

Lift, lift, lift. pthhfff.

Everthing that I have seen shows .465 as the point of diminishing returns.

DURATION, LOBE SEPERATION, OVERLAP.
edit: sorry about the yelling.

[This message has been edited by DanielKJenkins (edited 08-22-2004).]

Maybe its like the DOHC cams and the actual measured lift/duration is quite smaller than the "gm spec"

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[This message has been edited by donk316 (edited 08-22-2004).]

The dancing French girl is gone.

Thanks Donk. I was having flashbacks to 1976.

quote Originally posted by Solo2: You know Orief your statement differs than what is printed out of the ''93 service manual on Page 6A2B-55. Can you explain the difference here? Please.

I have no idea what the service manual says or why. I do know that the camshaft used in the 1993-1995 F-body cars is GM Part Number 10166324 and is listed for use in VIN S and L vehicles. These vehicles include (VIN L) 1986-1992 S-10/S-15 with 2.8L and 3.1L and (VIN S) 1985-1995 F-body 2.8L, 3.1L, and 3.4L. Which is noted as being .386/.387 lifts on the GM part description on the GM master Part index. This is the P/N for the camshaft of the RWD version of the 60* V-6's with fuel injection.
The Fiero cam is GM Part Number 14031378 and GM lists it as .394/.410 lift and used in (VIN 9) 1985-1988 2.8L
The only other camshaft I have info on is the GM P/N 14024278 which is lised as .372/.392 and being used on 1982-1985 VIN L 2.8L (carb'd 2.8L in trucks) 1982-1983 VIN S (carb'd 2.8L in the F-body cars)
I don't have the camshaft P/N or specs on the ones used in the FWD carb'd 2.8L or the FWD non-Fiero 2.8L which were used on the Cavalier/Sunbird and the Celebrity/P6000 vehicles. If I remember the Cavalier/Sunbird/Celebrity/P6000 cam was the .385/.401 cam but I cannot be 100% positive on it. I also do not have camshaft specs for the 3.1L FWD (with cast heads) or the 3100 FWD engines.

When I was building my engine I searched cams thru GM as to what they used and If you measure with the cam in your hand the total height from casting to the peak of the lobe Then measure the opposite side of the lobe, Subtract "A" from "B" and that is Total lift. Which if it is the cam you think it is you should measure about .262" I measured about .257"

GM buys their cams from Crane and Crower. If your cam is stamped "CC" or "CCC" it was made by Crane, The "CWC" cams were the ones made by Crower.

[This message has been edited by Oreif (edited 08-23-2004).]

Why dont' you ask yourself.... err I mean No1 CSP. he has tons of great technical knowledge. He doesn't forget anything about these engines or cars.

Its just too bad that you.. errr I mean him, can't find his way out of trolling posts in the mall section.

Yep you goofed and we all now know. Say hello to all your new negs.

I find it kind of funny how you create a second name, just to start sh!t in my threads, and now moving into other mall threads to start crap there too. Just do it under yoru own name you wuss.

Well at least everyone knows who you are now. Later on Sol... err i mean No1. c... errr I mean Trollboi.

------------------
JM / SH

I gotta have more cowbell!!!

quote Originally posted by Solo2: You know Orief your statement differs than what is printed out of the ''93 service manual on Page 6A2B-55. Can you explain the difference here? Please.

You know solo2 your stats on the stock Fiero cam do not match up with the GM performance parts catalog. The performance catalog shows the lift of the stock Fiero cam as: .394 intake and .410 exh. Can you explain the difference here?
You were proven wrong by Oreif and a couple others including myself about the aftermarket cam issue and ever since you've had nothing but venom towards oreif. That's childish at best. Everyone's wrong at one point or another and he certainly wasn't rude to you when he pointed out your mistake so why all the hate? Learn from it and move on.

------------------
Activities Director N.I.F.E.

www.fierofocus.com

So in short. What is the best aftermarket cam and lifters to get for a 3.4 liter 95' Camaro motor going into a smog equipped 87' GT. Thanks, Jeff

[This message has been edited by jawz68 (edited 08-23-2004).]

quote Originally posted by jawz68: So in short. What is the best aftermarket cam and lifters to get for a 3.4 liter 95' Camaro motor going into a smog equipped 87' GT. Thanks, Jeff

If you want to play it completely safe your best bet is the Crane 260. This is a dual pattern cam which these engines respond to much better then a single pattern cam. This cam and the bigger 272 Crane cam will provide more gains then the compucam even if the ompucam has 1.6 rockers. This is again due to the split pattern cam and the superior duration numbers to the compucam. Even if you put 1.6 rockers onto the compucam, you will still have smaller duration and a single pattern cam. The original HO cam the the Fiero cam with was a dual pattern cam and this was done for a reason.
I guess there is someone who has passed emissions with the Crane 272 cam and i have no problem believing this but i do not know this individual personally so i can't say for sure. The 272 has been dyno proven to give 15 HP to a 2.8 so it is preferable to the 260 which would give less. If you wanted to use the 272 you can put on an adjustable fuel pressure regulator and knock the pressure down some just before the test and then adjust it back up after you've past. I have a friend that did this with a 5 liter Mustang engine and it worked like a charm. He could not pass no matter what else he did so i suggested this idea and it worked the first time. He did it right before he pulled into the testing facility (in their own parking lot) and then dialed it back up when he drove outside so as not to do any damage by running it lean. Even the 272 really isn't that big of a cam as far as cams go so i doubt it would take much to get it to pass if it didn't pass. You really should have an adjustable fuel regulator anyway whenever you start modding the engine.

"Subtract "A" from "B" and that is Total lift. Which if it is the cam you think it is you should measure about .262" I measured about .257""

Oreif, that is only a 2% error which is pretty close to the upper spec limit. It verifies that the specs printed in the Service manual is correct. Actual spec limits is .231" to .262". You fit within the spec tolerance.
So it sums it up both the 2.8L and 3.4L cam have not only the same lifts but also the same +/- spec tolerances. BTW Oreif I can take a jpg picture of the page out of the Service manual and you can see first hand what is printed in the '93 Camaro Service manual.

Intake = .2626"
Exhaust = .2732"
Install valve spring height = 1.575"
Reference Info from '88 Fiero Service Manual
Page 6A2-23
2.8L V6 ENGINE P CARLINE
Anybody who has the service manuals can verify this and please print what specs are out of the other years service manuals.
Q: Is it possible for GM to print one set of specs for the Service Manuals and then print another different spec for their performance part books?

Another subject:
The Punisher, I do not know what is your problem. You think we are the same. I am not him, however I do know of him some years ago at a past employeer. He had a '88 and introduced me to the '88 fiero. That is why I have an '88, but that was four years ago. I have not seen or heard from him since.

I only know one thing and that is the '88 model year , I know nothing about the other years and will be the first to admit it. Will repeat this statement as many times as you wish.

It is interesting that this mentioned lift question brings up such interest. I too want to get to the bottom of this. I believe that it is not common practice for GM to print such errors in their Service Manuals, but nothing is perfect, maybe this is one of them.
Any further comments or ideas guys.

quote Originally posted by Solo2: "Subtract "A" from "B" and that is Total lift. Which if it is the cam you think it is you should measure about .262" I measured about .257"" Oreif, that is only a 2% error which is pretty close to the upper spec limit. It verifies that the specs printed in the Service manual is correct. Actual spec limits is .231" to .262". You fit within the spec tolerance. So it sums it up both the 2.8L and 3.4L cam have not only the same lifts but also the same +/- spec tolerances. BTW Oreif I can take a jpg picture of the page out of the Service manual and you can see first hand what is printed in the '93 Camaro Service manual.

Well considering the cams are actually made by aftermarket companies for GM, I would guess GM wrote the spec tolerance so they could use either cam. Which now means that with such a wide tolerance in the cam spec and the wide tolerance of the stock rockers (Many of the sets I've checked vary from arm to arm within the same engine) Your best bet when doing an engine swap or rebuild is to buy an aftermarket cam and rockers just from an accuracy point. As I stated the GM part number for the 3.4L equates to the .386/.387 Economy camshaft per GM master listing. If you add 2% yes it could be as large as a Fiero cam, But now add the same 2% to the Fiero cam and it is larger than the cam in a 3.4L could ever be. I believe the specs on the GM master listing are more accurate than the specs listed in a service manual. This is because most companies when they purchase parts from an outside vendor tend to be more critical with what they are buying spec wise. I am also sure Crane or Crower tend to be more accurate when grinding a cam than the 2% GM quotes.
So by your own example that the cam specs with the large 2% tolerances can be just about anywhere.

quote Originally posted by Solo2: I believe that it is not common practice for GM to print such errors in their Service Manuals, but nothing is perfect, maybe this is one of them.

You should read some GM service manuals more often. There are plenty of mistakes made. You can go to any dealership and look up what pages are corrected for each manual.
Isn't the 88 Fiero service manual the one that has a servicing section for the power steering that never made it in a production car? Or how about the speeding tickets Buick was forced to pay because they forgot one word in the 1987 Grand National service manual? The GN manual had a huge warning statement that stated:
"Regardless of national speed limits, This vehicle should be driven faster than 85mph otherwise the warranty could be voided"

Yes it was suppose to say:
"Regardless of national speed limits, This vehicle should NOT be driven faster than 85mph otherwise the warranty could be voided"
and Buick did send out an adhesive backed page that was suppose to be inserted in the service manual with the corrected statement.

Point is they might have wanted to use the .394/.410 cam in the 3.4L when the service manual was printed, But the cam could have changed to meet emission specs or the engine build sheet was different which shows the .383/.387 cam and so the engines were built with the economy cam.

[This message has been edited by Oreif (edited 08-23-2004).]

quote Originally posted by Solo2: The Punisher, I do not know what is your problem. You think we are the same. I am not him, however I do know of him some years ago at a past employeer. He had a '88 and introduced me to the '88 fiero. That is why I have an '88, but that was four years ago. I have not seen or heard from him since. I.

Its amazing that as you have not heard or seen him for so long you knew exactly who he was just by his name? Umm yea ok man. You aren't fooling anyone.

------------------
JM / SH

I gotta have more cowbell!!!

Which, BTW, is the same identical cam (260) supplied in the 3.4L HT Conversion engine. I just put mine together last week and degreed it in with the Crane cam card.

It also responds well to more compression and 1.6 ratio rockers.

John Stricker

quote Originally posted by Dave Gunsul: If you want to play it completely safe your best bet is the Crane 260. This is a dual pattern cam which these engines respond to much better then a single pattern cam.

quote Originally posted by jstricker: Which, BTW, is the same identical cam (260) supplied in the 3.4L HT Conversion engine. I just put mine together last week and degreed it in with the Crane cam card. It also responds well to more compression and 1.6 ratio rockers. John Stricker

I just found out recently that the lobe sep is actually different between the 260 and the cam used in the HT 3.4. The HT's engine is a tighter band of power then the 260 cams is probably because the HT is intended for a truck. The 260 cam is intended for more of a performance application with a wider power range over a broader rpm range. 1.6 rockers on the 260 cam change the lift to what the 272 cam is but you won't have as much duration. 1.6 rockers on a new HT 3.4 is a good idea because it will add some power without the need to tear a brand new motor apart for a cam change. A bigger cam would give more gains then the rockers and also be easier on the valve train but, with a brand new motor, it makes more sense to use 1.6 rockers. The HT engine should have stronger springs since it's using a fair ammount of lift so using 1.6 rockers is an easy upgrade too unlike the stock Fiero engine where the springs are only rated up to 420 lift.

Add to the list the 81-84 Z code HO engine. Same cam, pistons, heads, etc. as the Fiero V6.

I don't think so. If it is you'll have to explain to me how it can degree out exactly to the Crane cam card and have a different lobe separation. It degrees in exactly like a Crane 260. What they did do is advance the timing 2.5 degrees. That's where the extra torque comes from, but the cam profile itself is identical. The Cloyes true roller timing set has a crank gear that offers a 0, -4, and +4 setting, but that would have resulted in a timing that was 6.5 degrees advanced or 1.5 degrees retarded. I didn't want it advanced that much and I didn't really want it retarded at all since the relatively stock intake most likely won't flow enough to see the benefit of it anyway, so I left it as it came out.

Come to think of it, I have a set of offset bushings (probably Crane or Mr Gasket) in my box for a SBC, I wonder if the pin on the cam is the same size as a SBC? With that, I could have pulled the timing back and gotten it closer to 0 (+/- 1/2 degree), but I didn't think about it then.

You won't have the duration of a 272 with the 1.6 rockers, but surprisingly you do gain some EFFECTIVE duration. While it's true that the valves won't start moving any sooner with 1.6 rockers as opposed to 1.5, they will get to that magic .050" valve lift a couple of degrees sooner because that is the point the ramp is the steepest and everything moves just a little bit faster. I was going to measure that when I was putting the engine together to see the timing difference a .050" lift with the two rockers, but forgot about it.

The HT engine does have beefier springs, but I used the Comp Cams springs and retainers anyway. I may keep the HT springs to use if I ever rebuild one of the 2.8's I have laying around.

John Stricker

quote Originally posted by Dave Gunsul: I just found out recently that the lobe sep is actually different between the 260 and the cam used in the HT 3.4. The HT's engine is a tighter band of power then the 260 cams is probably because the HT is intended for a truck. The 260 cam is intended for more of a performance application with a wider power range over a broader rpm range. 1.6 rockers on the 260 cam change the lift to what the 272 cam is but you won't have as much duration. 1.6 rockers on a new HT 3.4 is a good idea because it will add some power without the need to tear a brand new motor apart for a cam change. A bigger cam would give more gains then the rockers and also be easier on the valve train but, with a brand new motor, it makes more sense to use 1.6 rockers. The HT engine should have stronger springs since it's using a fair ammount of lift so using 1.6 rockers is an easy upgrade too unlike the stock Fiero engine where the springs are only rated up to 420 lift.

Regarding cam lift and displacement as relates to engine displacement, the smaller the engine the more aggressive a given set of cam specs will be. A hot cam for the 2.8 will be mild in a 3.4.

JazzMan

quote Originally posted by jstricker: I don't think so. If it is you'll have to explain to me how it can degree out exactly to the Crane cam card and have a different lobe separation. It degrees in exactly like a Crane 260. What they did do is advance the timing 2.5 degrees. That's where the extra torque comes from, but the cam profile itself is identical. The Cloyes true roller timing set has a crank gear that offers a 0, -4, and +4 setting, but that would have resulted in a timing that was 6.5 degrees advanced or 1.5 degrees retarded. I didn't want it advanced that much and I didn't really want it retarded at all since the relatively stock intake most likely won't flow enough to see the benefit of it anyway, so I left it as it came out. Come to think of it, I have a set of offset bushings (probably Crane or Mr Gasket) in my box for a SBC, I wonder if the pin on the cam is the same size as a SBC? With that, I could have pulled the timing back and gotten it closer to 0 (+/- 1/2 degree), but I didn't think about it then. You won't have the duration of a 272 with the 1.6 rockers, but surprisingly you do gain some EFFECTIVE duration. While it's true that the valves won't start moving any sooner with 1.6 rockers as opposed to 1.5, they will get to that magic .050" valve lift a couple of degrees sooner because that is the point the ramp is the steepest and everything moves just a little bit faster. I was going to measure that when I was putting the engine together to see the timing difference a .050" lift with the two rockers, but forgot about it. The HT engine does have beefier springs, but I used the Comp Cams springs and retainers anyway. I may keep the HT springs to use if I ever rebuild one of the 2.8's I have laying around. John Stricker

All i can tell you is what i read. The lobe sep is listed differently for the two cams. It wouldn't be the first time GM has listed something wrong though of course. If you've actually checked it then they must have but when i looked at the cam specs in the Gm catalog as opposed to the Crane 260 in the Crane catalog, they were different lobe seps.
I agree with everything you've posted.
The 1.6 rockers do effect duration to a small level but, as i said, you will not have as much duration as the 272. That wasn't stated as an argument or anything i just wanted to say it so people who might not know as much about cams were aware of that fact. There are some who think that lift is everything and it's not so that's why i went into that.
Probably not a bad idea to use the Crane springs & retainers even though it probably wasn't necassary. Better safe then sorry. Probably not a bad idea to use better valve guide seals while you're at it. Every Fiero owner knows how cheap Gm tends to be with those if they have a V6. :O/

Dave,

I didn't think you were "picking a fight" or anything like that, I was sure you based your statement on something you'd read.

I did degree the cam in and checked both intake and exhaust lobes and they matched perfectly the Crane 260 cam card with the exception of the 2.5 degree advanced setting. While a company like GM can do whatever they want, it really wouldn't make much sense for them to change a known, good grind like that. (Wait a minute, this is GM, what am I saying?? )

I did use the FelPro stem seals. One thing that needs to be checked when running a high lift cam is that the retainers don't come down and hit the tops of the seals. If they touch, they'll cut the tops out in short order. The top of the guides may have to be trimmed.

One of these days when I'm putting an engine together I'm going to remember to actually check and see how much difference there is in the duration at .050" with 1.6 rockers as compared to 1.5 rockers. I doubt it's more than 3 or 4 degrees, but it would be interesting to know. Why are we always building engines for the race cars the day before we need to race? Whay can't the parts come in on Wednesday instead of Friday? These are questions that will haunt me to the grave.

John Stricker

quote Originally posted by Dave Gunsul: All i can tell you is what i read. The lobe sep is listed differently for the two cams. It wouldn't be the first time GM has listed something wrong though of course. If you've actually checked it then they must have but when i looked at the cam specs in the Gm catalog as opposed to the Crane 260 in the Crane catalog, they were different lobe seps. I agree with everything you've posted. The 1.6 rockers do effect duration to a small level but, as i said, you will not have as much duration as the 272. That wasn't stated as an argument or anything i just wanted to say it so people who might not know as much about cams were aware of that fact. There are some who think that lift is everything and it's not so that's why i went into that. Probably not a bad idea to use the Crane springs & retainers even though it probably wasn't necassary. Better safe then sorry. Probably not a bad idea to use better valve guide seals while you're at it. Every Fiero owner knows how cheap Gm tends to be with those if they have a V6. :O/

Well i'm glad we had this discussion about the cams JStricker, i had thought it was odd that Gm would use a different grind but then figured it must be because of the truck application. I had thought about using the HT 3.4 but that lobe sep. issue had me worried that it might not be the best for a performance application like the Fiero but i'm glad to find out that they did actually use the 260 after all. That might make the HT more likely to end up in my car with 1.6 rockers too, although, i am really interested in the 3.4 TDC now instead....Decisions, decisions. I wish GM would get a good proof reader for once. lol

quote Originally posted by Dave Gunsul: I had thought about using the HT 3.4 but that lobe sep. issue had me worried that it might not be the best for a performance application like the Fiero but i'm glad to find out that they did actually use the 260 after all.

I tried to find my cam card today. I was going to run the Crane H260 in my 3.4 but I had a friend who is a Pontiac parts guy checkthe price on the HT camand lifters for me and it was a lot less expensive so I got it from him along with the mtching springs and the retainers to get the corect spring height. I checked my card then and compared it to the specs Crane listed for the H260, I recall all the specs being the same.
I am happy with the cam but will be installing the 1.6 rockers at some point to get a bit more snap out of it.
Hope this helps

------------------

85 GT 4-speed
3.4 pushrod, 390 Holley carb, Edlebrock intake, MSD 6A ignition. 04 Gran Prix exhaust tips, Ported manifolds and lots more to go.
Richey

Powermax H-260-2

. PowerMax Hydraulic Lifter Camshafts for Emissions Controlled Vehicles without computer
Application Series & Grind Number
Good idle, daily usage and off road, towing, economy, also mild turbocharged, 2200-3000 cruise RPM, 8.0 to 9.5 compression ratio advised. Basic RPM 1500-4500 PowerMax H-260-2replacing: HMV-260-2
Cam Specifications
Degrees Duration @ .050 Int./Exh. Degrees Advertised Duration Int./Exh. Degree Lobe Separation Open/Close @.050" Cam Lift Int./Exh. Lash Hot Int./Exh. Gross Lift Int./Exh.
204216 260272 112 (5) 2945 (9) .000.000 .427.454
Valve Train Components
Camshaft 253901 *253902 *b b Cam and Lifter Kit, includes installation lubricants.
Lifters 99286-12 *
Valve Springs 99848-12 Standard diameter valve springs, no machining required.
Retainers 99915-12 *
Valve Stem Locks 99041-1 99097-1 e e Machined steel, heat treated.
Pushrods 25621-12 For cast iron inline-valve cylinder heads, heat treated, for use with pushrod guideplates.
Gold Race Rockers 25750-12 g25759-12 h g 1.5 ratio, narrow body (not self-aligning), with special 10mm x 1.50 bottom x 3/8" x 24 top rocker arm studs included. h 1.6 ratio, narrow body (not self-aligning), with special 10mm x 1.50 bottom x 3/8" x 24 top rocker arm studs included.
* This product is applicable only to pre-1966 California and pre-1968 federally certified passenger cars. It is also applicable to non-emission controlled trucks and similar vehicles. It is not applicable or intended for use on any emission controlled vehicles operated on highways or roads.

When you install the rockers, be sure to check your clearance between the bottoms of the retainers and the top of the valve stem seals. If you don't, you run a very good chance of having them hit and cut the tops out of the seals.

John Stricker

quote Originally posted by STRATOHACKER: I tried to find my cam card today. I was going to run the Crane H260 in my 3.4 but I had a friend who is a Pontiac parts guy checkthe price on the HT camand lifters for me and it was a lot less expensive so I got it from him along with the mtching springs and the retainers to get the corect spring height. I checked my card then and compared it to the specs Crane listed for the H260, I recall all the specs being the same. I am happy with the cam but will be installing the 1.6 rockers at some point to get a bit more snap out of it. Hope this helps

quote Originally posted by jstricker: When you install the rockers, be sure to check your clearance between the bottoms of the retainers and the top of the valve stem seals. If you don't, you run a very good chance of having them hit and cut the tops out of the seals. John Stricker

Thanks for the tip I'll keep that in mind.
The retainers that I installed though are quite different from the stock retainers so that the stiffer springs have the correct install height. I will double check them when I do the rockers but I do not think it will be a problem. I am also using the Fel-Pro seals, much better than stock.
Richey