What cams are you guys running for your DD's?

[CherryK5]

Short story: Spun a bearing and F'd my crank. I have another forged one laying around so that's going in. But while its apart im putting in a new cam.

But now i need to know what bearings and cam to go with.

i don't want to go broke with mega high end bearings and cam, i just need something mid range that will out perform stock stuff.

I have a Chevy Performance zz4 crate motor with a Holley 650cfm carb.
(Somewhere around 400 hp, 420 ft.lbs at the flywheel according to the birth sheet, im not sure about the exact numbers)
700R4, 35 inch tires and 4.10's

The cam in it is way to radical for a truck, the hp peaks at 5250 and my truck has never been revved that hard so i want something a little more mild.

I'm looking for a cam with good low end torque from 1500-3500 rpm, if possible, and a decent hp curve around the same range.

My dad has his towing cam out of his old wrecker that might work but i don't know much about it.

And im going to go with a TBI setup while its all apart too if that helps with the suggestions, i know there are tbi specific cams out there.

So any suggestions? What cams are you guys running?

 

[CherryK5]

Come on guys I know most of you are running aftermarket cams.
Don't leave me hangin'

 

[CGT80]

tbi requires a very specific cam from what I have seen. I am a bit stuck on what to do for a new engine in my 88 k5 because it is tbi and cali smog.

The 383 in my 79 C20 pickup was setup with the edelbrock performer intake, heads, and a cam with the same specs. It pulled well, but the cam, 204/214 at .050 was specified for a 350 so it was too small for the 383. Also I learned that when my 383 was built, the head gasket was too thick which reduced compression and the squish quench effect of the head. The edelbrock performer cam that i had might be near what you would need for a 350 but wouldn't be right for a tbi motor. edelbrock does have a tbi cam. It is smaller than a non tbi cam and may cost you some power.

I have a head and intake guy designing a 406 for me. He actually has studied the physics of what makes all of the parts work together. He can run up to a 10.5:1 CR and a good size custom ground cam, yet have a smooth idle and pass smog without detonation by making sure everything in the top end is setup properly. Also, thermal coating the valves and intake will aid in reducing detonation and increasing power. He expects to see almost 525 ft. pounds of torque from this combo using the heads and intake from my 383. The bottom end will reuse my rods.

From what I have learned, I am not sure you will get the horsepower to max out that low or that it would help in a truck. I was hoping to freshen up my 383 for my truck since it lost a head gasket, but my cam was also worn out, the cylinders need bored and the crank needs turned. A 406 vs a 355 made 113 ft. pounds more tq in a hot rod magazine article, and my head guy agrees. He builds engines that end up in magazines quite often, so they could have been some he worked on, i dont remember. by going up in cubic inches I will only be adding a block and new crank vs. boring the old block and turning the crank if I was to keep the 383. I will gain 75 or more foot pounds of torque by going up from 383 to 406. It all depends on how inefficient my 383 was.

I would stay away from the TBI injection unless you can find someone who can upgrade and tune it for you, who can prove that they have successfully done it in the past. I believe it can be done, but it is more complicated than slapping on a 900 cfm carb. vs. a 600 for an upgraded engine. I have heard great things about Brian at TBIchips.com

I thought my 383 was built as well as possible. It had a ton of power, but I couldn't tell it was lacking just by driving it. I would have had to dyno it or like I did, have someone tear it apart to see what was really done.

I could have a nice 383 built for my tbi blazer and try to upgrade the fuel system. It may run stronger than stock, but would I really be getting the full potential from the engine? If I was going to put the money into it, I would want to see proof, eg. dyno numbers.

Well, I am no pro, but I hope some of what I have seen with my projects gives you some ideas.

 

[CherryK5]

tbi requires a very specific cam from what I have seen. I am a bit stuck on what to do for a new engine in my 88 k5 because it is tbi and cali smog.

The 383 in my 79 C20 pickup was setup with the edelbrock performer intake, heads, and a cam with the same specs. It pulled well, but the cam, 204/214 at .050 was specified for a 350 so it was too small for the 383. Also I learned that when my 383 was built, the head gasket was too thick which reduced compression and the squish quench effect of the head. The edelbrock performer cam that i had might be near what you would need for a 350 but wouldn't be right for a tbi motor. edelbrock does have a tbi cam. It is smaller than a non tbi cam and may cost you some power.

I have a head and intake guy designing a 406 for me. He actually has studied the physics of what makes all of the parts work together. He can run up to a 10.5:1 CR and a good size custom ground cam, yet have a smooth idle and pass smog without detonation by making sure everything in the top end is setup properly. Also, thermal coating the valves and intake will aid in reducing detonation and increasing power. He expects to see almost 525 ft. pounds of torque from this combo using the heads and intake from my 383. The bottom end will reuse my rods.

From what I have learned, I am not sure you will get the horsepower to max out that low or that it would help in a truck. I was hoping to freshen up my 383 for my truck since it lost a head gasket, but my cam was also worn out, the cylinders need bored and the crank needs turned. A 406 vs a 355 made 113 ft. pounds more tq in a hot rod magazine article, and my head guy agrees. He builds engines that end up in magazines quite often, so they could have been some he worked on, i dont remember. by going up in cubic inches I will only be adding a block and new crank vs. boring the old block and turning the crank if I was to keep the 383. I will gain 75 or more foot pounds of torque by going up from 383 to 406. It all depends on how inefficient my 383 was.

I would stay away from the TBI injection unless you can find someone who can upgrade and tune it for you, who can prove that they have successfully done it in the past. I believe it can be done, but it is more complicated than slapping on a 900 cfm carb. vs. a 600 for an upgraded engine. I have heard great things about Brian at TBIchips.com

I thought my 383 was built as well as possible. It had a ton of power, but I couldn't tell it was lacking just by driving it. I would have had to dyno it or like I did, have someone tear it apart to see what was really done.

I could have a nice 383 built for my tbi blazer and try to upgrade the fuel system. It may run stronger than stock, but would I really be getting the full potential from the engine? If I was going to put the money into it, I would want to see proof, eg. dyno numbers.

Well, I am no pro, but I hope some of what I have seen with my projects gives you some ideas.

actually I have someone who will tune the tbi. I have 100% faith in him. So I'm not scratching tbi off my list, I'm tired of the 6mpg BS that I've been dealing with, granted a heavy cam never helped.
And I'm well aware of the power loss. I'm fine with that, with a ton of power I ended up driving like the motor wanted me to. Three tranny's later and some maturity I'm looking for practicality and drivability rather than having a ton of power i'll never need.

So TBI and a nice drivable cam with some low end power rather than high revs is what I want.

 

[CherryK5]

So I guess the real questio should be what duration and lift I should look for.
I've never had to buy a cam before so I have no idea what to look for. Hence, me asking the brotherhood.

 

[CGT80]

http://www.edelbrock.com/automotive_new/mc/camshafts/cams_chevy_sb.shtml

edelbrocks tbi cam is listed as 194/214 duration at .050 and 398/442 lift. this is for a tbi 350 engine and a non-roller camshaft.

The cam listed for a carbed 350, the cam I had, was 204/214 420/442. It had a smooth idle in a 383 and made a lot of low end torque. In a carbed 350 it would act a little bigger, and should be a better match for a 350 than a 383.

I would consult with your tbi tuning person about cam specs. maybe they have tuned for a particular cam that worked well.

you could also check out comp cams or crane cams and see if they list a tbi 350 cam.

 

[Wyomingboy]

Here is a list of cams that are advertised to work well with TBI.

RECOMMENDED CAMS I have removed the Summit racing cams recently due to a lot of lifter issues with these cams.
Crane cams
Summit Part Number: CRN-113904
Basic Operating RPM Range: 1,500-4,500
Duration at 050 inch Lift: 206 int./218 exh.
Advertised Duration: 256 int./268 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.432 int./0.459 exh. lift
Lobe Separation (degrees): 112

Summit Part Number: CRN-113932
Basic Operating RPM Range: 1,600-5,200
Duration at 050 inch Lift: 210 int./216 exh.
Advertised Duration: 266 int./272 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.440 int./0.454 exh. lift
Lobe Separation (degrees): 114
Summit Part Number: CRN-113934
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,600-5,200
Duration at 050 inch Lift: 212 int./218 exh.
Advertised Duration: 262 int./268 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.446 int./0.459 exh. lift
Lobe Separation (degrees): 114

Edelbrock cams

SummitPart Number: EDL-3702
Basic Operating RPM Range: Idle-5,500
Duration at 050 inch Lift: 194 int./214 exh.
Advertised Duration: 244 int./264 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.398 int./0.442 exh. lift
Lobe Separation (degrees): 112

Summit Part Number: EDL-2102
Basic Operating RPM Range: Idle-5,500
Duration at 050 inch Lift: 204 int./214 exh.
Advertised Duration: 278 int./288 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.420 int./0.442 exh. lift
Lobe Separation (degrees): 112

Lunati cams

Summit Part Number: LUN-60100LK
Basic Operating RPM Range: 1,000-5,500
Duration at 050 inch Lift: 207 int./213 exh.
Advertised Duration: 250 int./256 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.437 int./0.454 exh. lift
Lobe Separation (degrees): 112


Summit Part Number: LUN-60101LK
Basic Operating RPM Range: 1,000-5,500
Duration at 050 inch Lift: 213 int./219 exh.
Advertised Duration: 256 int./262 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.454 int./0.468 exh. lift
Lobe Separation (degrees): 112
Cheapy Sealed Power cams
CS1014R
1500-4000 RPM Range
278 intake/288 exhaust Adv Dur
Duration @.050 204 intake/214 exhaust
Valve lift 420 intake/443 exhaust,
Lobe C/L 112
Strangely this cam has the exact same specs as a Summit 1102 HMM wonder who makes Summits Cams, Also looks exactly like the Edelbrock 2102 cam.

CS1105R
1800-4400 RPM Range
283 intake/286 exhaust Adv Dur
Duration @.050 209 intake/216 exhaust
Valve Lift .435intake/.455 exhaust
Lobe C/L 112
I haven't tried this cam yet but I may give the 1105R a try on project Plum Simple
Also Northern Autoparts Northern Auto Parts has the sealed power cams complete with timing chain and gears as well as the cam and lifters as a kit for under $100. Can't beat that for a budget build.

COMP CAMS

As you can see below as the duration gets higher so must the lobe separation angle.

 

[CherryK5]

Here is a list of cams that are advertised to work well with TBI.

RECOMMENDED CAMS I have removed the Summit racing cams recently due to a lot of lifter issues with these cams.
Crane cams
Summit Part Number: CRN-113904
Basic Operating RPM Range: 1,500-4,500
Duration at 050 inch Lift: 206 int./218 exh.
Advertised Duration: 256 int./268 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.432 int./0.459 exh. lift
Lobe Separation (degrees): 112

Summit Part Number: CRN-113932
Basic Operating RPM Range: 1,600-5,200
Duration at 050 inch Lift: 210 int./216 exh.
Advertised Duration: 266 int./272 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.440 int./0.454 exh. lift
Lobe Separation (degrees): 114
Summit Part Number: CRN-113934
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,600-5,200
Duration at 050 inch Lift: 212 int./218 exh.
Advertised Duration: 262 int./268 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.446 int./0.459 exh. lift
Lobe Separation (degrees): 114

Edelbrock cams

SummitPart Number: EDL-3702
Basic Operating RPM Range: Idle-5,500
Duration at 050 inch Lift: 194 int./214 exh.
Advertised Duration: 244 int./264 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.398 int./0.442 exh. lift
Lobe Separation (degrees): 112

Summit Part Number: EDL-2102
Basic Operating RPM Range: Idle-5,500
Duration at 050 inch Lift: 204 int./214 exh.
Advertised Duration: 278 int./288 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.420 int./0.442 exh. lift
Lobe Separation (degrees): 112

Lunati cams

Summit Part Number: LUN-60100LK
Basic Operating RPM Range: 1,000-5,500
Duration at 050 inch Lift: 207 int./213 exh.
Advertised Duration: 250 int./256 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.437 int./0.454 exh. lift
Lobe Separation (degrees): 112


Summit Part Number: LUN-60101LK
Basic Operating RPM Range: 1,000-5,500
Duration at 050 inch Lift: 213 int./219 exh.
Advertised Duration: 256 int./262 exh.
Valve Lift with Factory Rocker Arm Ratio: 0.454 int./0.468 exh. lift
Lobe Separation (degrees): 112
Cheapy Sealed Power cams
CS1014R
1500-4000 RPM Range
278 intake/288 exhaust Adv Dur
Duration @.050 204 intake/214 exhaust
Valve lift 420 intake/443 exhaust,
Lobe C/L 112
Strangely this cam has the exact same specs as a Summit 1102 HMM wonder who makes Summits Cams, Also looks exactly like the Edelbrock 2102 cam.

CS1105R
1800-4400 RPM Range
283 intake/286 exhaust Adv Dur
Duration @.050 209 intake/216 exhaust
Valve Lift .435intake/.455 exhaust
Lobe C/L 112
I haven't tried this cam yet but I may give the 1105R a try on project Plum Simple
Also Northern Autoparts Northern Auto Parts has the sealed power cams complete with timing chain and gears as well as the cam and lifters as a kit for under $100. Can't beat that for a budget build.

COMP CAMS

As you can see below as the duration gets higher so must the lobe separation angle.

That is computer code to me...

In english, which one is most like what i wanted?
because i would just do inny-minny-miney-mo and call it done because i have no idea what all that means.

All i know is i want lots of low end torque. I've got an auto trans for gods sake, what am i going to do with a cam with a power curve peaking at 5000+ rpm?

Edit: i know that longer duration yields more power and a higher rpm power, and that more lift does something too. =] But too much overlap does bad things. bahahaha

 

[4xcrazy]

what cam am I running??

stock,, other than being a roller unit,,, it's the best one for a TBI computer without having to hassle with reprogramming it.

personally, the way i see it, if ya want high horsepower, get a hot rod car, if ya wanna use your truck for a long time, build it to last. I went with the roller,,yes,, to free up alittle HP, perhaps, but mostly cause i believe they would last longer with less wear issues than a standard flat tappet lifter setup.

 

[76zimmer]

buy an engine dyno program...invaluable for testing stuff like this.

I would search for about a 114 c/l and about 450/460 lift with about 204-210 duration @.050. If it would work with TBI, I don't know.

 

[CherryK5]

buy an engine dyno program...invaluable for testing stuff like this.

I would search for about a 114 c/l and about 450/460 lift with about 204-210 duration @.050. If it would work with TBI, I don't know.

Sounds good, so now i know what to look for.

What attributes make the idle radical/smooth
And what attributes tell it where to make power?

 

[mudbuggy]

I think if I were you a I would look to a cam that replicates factory specs. Then at least you would be able to break double digits in fuel economy. Once the powerplant is set back in it's home, it would not require pulling the whole thing to add horsepower, meaning you would be able to swap out the heads with ported heads when you want. Swap out the TBI for a overbored unit when money if easier to come by. The biggest bitch I see going from carb to TBI is installing a fuel pump in the tank, yea you can get an inline pump and mount it on the rail, but that's a the same price as an overbored TBI unit! I understand about the mpg. Maybe drop the tank and figure out exactly where the opening is for the fuel pump in the tank is and cut a hole in the body.

 

[CherryK5]

I think if I were you a I would look to a cam that replicates factory specs. Then at least you would be able to break double digits in fuel economy. Once the powerplant is set back in it's home, it would not require pulling the whole thing to add horsepower, meaning you would be able to swap out the heads with ported heads when you want. Swap out the TBI for a overbored unit when money if easier to come by. The biggest bitch I see going from carb to TBI is installing a fuel pump in the tank, yea you can get an inline pump and mount it on the rail, but that's a the same price as an overbored TBI unit! I understand about the mpg. Maybe drop the tank and figure out exactly where the opening is for the fuel pump in the tank is and cut a hole in the body.

Well I have all the tbi stuff off of a 91 burb. The tank is bigger though so I dunno if the pump will change out.

 

[4X4HIGH]

Well, a ZZ4 engine uses a hydraulic roller cam from the factory so are you going to stay with hydraulic roller? I'm running a Comp Cams #08-464-8 (hydraulic roller)

Cam specs are as follows...

202*/212* @ .050"
.550"/.546" with 1.6 ratio rockers
113* Lobe Separation Angle

 

[mudbuggy]

You could scab (cut) out the fuel pump mount out of the 91 burb tank and reattach it to the K5 tank. I would make sure that the top of the unit doesn't hit a cross member on the body once it is finally reinstalled in the truck. That or find out if your year and and a k5 tbi have the same size tank and source a tank! Me personally I'd scab the tank just as a challenge! That's just me though!

 

[CherryK5]

Cam specs are as follows...

202*/212* @ .050"
.550"/.546" with 1.6 ratio rockers
113* Lobe Separation Angle

That means nothing to me...

That's why I was asking what this stuff means.
I wiki'd it but learned nothing..

 

[4X4HIGH]

Ok, duration is the amount of time that the valves are open during tappet lift (typically measured at .050" tappet lift)

Valve lift should be self explanatory (sometimes cam manufacturers list lobe lift instead which you would then need to multiply by the rocker ratio being used).

Lobe Separation Angle is the distance between the intake and exhaust lobes measured in degrees.

Typically the smaller the duration is the more low end power it will make and the larger the duration the more top end power it will make.

With lobe separation angle the smaller the number the less vacuum the engine will produce and the choppier the idle will be.

 

[COCHEV]

Well, a ZZ4 engine uses a hydraulic roller cam from the factory so are you going to stay with hydraulic roller? I'm running a Comp Cams #08-464-8 (hydraulic roller)

Cam specs are as follows...

202*/212* @ .050"
.550"/.546" with 1.6 ratio rockers
113* Lobe Separation Angle

is the stock puter happy with this cam?

 

[4X4HIGH]

That I couldn't say for sure as i'm also running a 454 TBI unit which required a chip burn BUT the specs should not scare a factory chip by any means. My engine still runs with close to 18 hg of vacuum which is fine for any FI system.

 

[CherryK5]

Ok, duration is the amount of time that the valves are open during tappet lift (typically measured at .050" tappet lift)

Valve lift should be self explanatory (sometimes cam manufacturers list lobe lift instead which you would then need to multiply by the rocker ratio being used).

Lobe Separation Angle is the distance between the intake and exhaust lobes measured in degrees.

Typically the smaller the duration is the more low end power it will make and the larger the duration the more top end power it will make.

With lobe separation angle the smaller the number the less vacuum the engine will produce and the choppier the idle will be.

and now it all makes sense!!

so I want something with a semi-short duration and little intake/exhaust overlap (if any)

sound about right?

what does the variation in lift do? Sorry if I'm being that guy, I'm just trying to get informed. I love knowing this stuff.

Teach a man to fish..