[TurboS10]

Hey all,

I am in the process of hunting for cams for my turbo engine rebuild and thought I would see if any of you want to take a stab at the selection. If you dont know combo is as follows:

S-10 truck, 3000lb
9 inch, 3:50 gears
TH350, 10 inch converter - 3500-4000 RPM stall

SBC 400 (.040 over)
23cc dish pistons
6" rods
Dart Pro1 heads, 230cc intake, 72cc chambers, 110# springs(dont want to change)
Edelbrock Proflo hardware(Victor Jr.)
Large frame Garrett turbo, 76mm inducer

This truck is primarily for the track so power potential is the ultimate goal. I need to be able to keep around 12 inches of vacuum to be able to tune idle. The turbo I am running is pretty large so reversion is not as much an issue as with smaller turbos.

I want to stay around .500-.525 lift. I also dont want to spend the money for a roller conversion. Hydraulic or mechanical flat tappet is what I am looking for.

I have picked two crane cams in the range I am looking at:

Crane Cams
Product Line Crane PowerMax Camshafts
Cam Style Mechanical flat tappet
Basic Operating RPM Range 3,800-7,200 RPM
Intake Duration 050 inch Lift 248
Exhaust Duration 050 inch Lift 258
Advertised Intake Duration 288
Advertised Exhaust Duration 298
Intake Valve Lift with Factory Rocker Arm Ratio 0.500
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.520
Lobe Separation (degrees) 114
Intake Valve Lash (in) 0.022
Exhaust Valve Lash (in) 0.022
Grind Number F-288-2

-and-

Crane Cams
Product Line Crane PowerMax Camshafts
Cam Style Mechanical flat tappet
Basic Operating RPM Range 3,400-6,800 RPM
Intake Duration 050 inch Lift 244
Exhaust Duration 050 inch Lift 252
Advertised Intake Duration 280
Advertised Exhaust Duration 288
Intake Valve Lift with Factory Rocker Arm Ratio 0.518
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.536
Lobe Separation (degrees) 112
Intake Valve Lash (in) 0.026
Exhaust Valve Lash (in) 0.026
Grind Number F-280-2

Let me know what you think and if you have any other cams in mind that might work well.

Chris

 

[camaroman7d]

Chris,
May I suggest giving Engle Racing cams a call? (talk to Mark Engle) That is who ground the cam for my blowm engine. They are great and will cater to your requests/needs. They have experience with boost. I went with a solid flat tappet and it does EXACTLY what I asked for. I could not be happier. They had a very fast turn around and the price wasn't bad at all. This way you get what you want and are not limited to something "close".


www.englecams.com

Royce

 

[TurboS10]

Thanks Royce. I will get in touch with them and see what they think. What kind of prices are we talking for something like that?

Chris

 

[lluciano77]

With all the money you have spent already Turbo, why are you against going with a solid roller? I would think that would be the finishing touch to an engine like yours.

 

[TurboS10]

My main hangup with the roller is the money. I know it is better, but it is just alot of money to spend. I bet you would be surprised how little I have in my engine. I am ready to get it back together and decided to go with the big Dart heads over a roller cam. I just cant afford to do it all right now. I am ready to race this thing. I dont need the size that the roller cam affords with my engine. I can get all the cam I need in a flat tappet. Those heads will put 100HP or more in my engine at low boost level and much more in high boost levels. A roller cam might get me 30HP and the cost is about the same.

Short and sweet: I am a cheapa$$

Chris

 

[lluciano77]

I know what you mean. It is hard to convince the wife to let another big purchase by.

 

[camaroman7d]

Chris,
Sorry for the delay, I was out and about. I dug up my invoice. My total was $271.96 for cam and lifters. I had to pay tax which you won't (that's $20), shipping was $10 so the actual cam and lifters were ~$240. Mine was ground on a p-55 core (doesn't mean much to me but, it's supposed to be good) and "race" solid lifters.

I dealt directly with them, if they have a dealer in your area you may or may not be able to save a couple bucks.

Personally I think you are making the right choice staying away from the solid roller, if you plan on driving it on the street. I learned a VERY expensive lesson doing that. While you can make them live in order to do it right it is even more expensive than the basic solid roller/lifter kits you see advertised for ~$500. For your RPM level and lift level, there really is no need to run a solid roller. I doubt it would by you anything really.

Here are my cam specs, just so you have an idea of what we (me and Engle) decided on.

adv. duration 288/292, duration @.050 248/257, 112 lobe centers, .530/.534 lift, .018/.020 lash

I also run 1.6 rockers so my actual lift is .554/.570.

I am sure you will want something a little different for your turbo. With my blower, it is absolutely perfect for what I wanted. It makes power from idle on up I never took it to the point it stopped pulling so I don't know how high it will rev (I have seen ~6800 so far).

They will ask you for details which I am sure you already have and they will ask what you want from this cam. That's why I really liked dealing with them, they didn't tell me what to buy, they made a suggestion based on what I was asking for. They hit the nail on the head, I even wrote them telling them how pleased I am. It was well worth the extra few bucks. There really aren't many off the shelf cams to choose from for boosted applications. Please let me know how it goes when you call them, I would be interested in seeing what they suggest and what you guys settle on.

Royce

 

[67 Deuce 4 Me]

Turbo .Did you like your heads? last time we talked they were in transit.....Did you get them From Yodders on Ebay? I love mine I thought they were a great buy at 925.00 assembled.

 

[TurboS10]

Thanks Royce. I will give them an email. They are going to have to do some selling to get me past that $280 price tag. If you look, yours is strikingly close to the second crane I found. I am curious what they suggest on the exhuast side for my engine.....

67 Duece. I have not got the heads in my hands yet. I am eagarly waiting. I am glad to hear yours are what you ordered and you are happy. I cant wait to get my hands on those bad boys.

Chris

 

[Cstraub]

Chris,
I don't feel you'll need anything with that much duration to make good power. Something in the 220 range and .525 lift range should work the best. Some of the turbo Pro 5.0 cars don't run that much duration and make 1500HP +.


Chris

 

[camaroman7d]

Chris,
I did notice that the cams you listed weren't to far off from what I have. Your price should be closer to $240, you are out of state. The sales tax here are high. I know what you mean though you can get an off the shelf cam for about half that. Just thought I would share my experience.

As far as the duration, I think it really depends on yuor goals. Kind of hard to compare a street engine to a 1500HP engine. I am sure they have VERY efficient heads and huge turbos. In that case they don't really need as much duration. I bet they have pretty high lift and very aggressive ramps (solid roller) and you can't get that with a flat tappet cam. I am not a turbo guy so I don't know all the ins and outs. In my case power comes on from idle on up, I can't even imagine have more low end torque. Now a turbo may be a different story.

Please post back with what you decide. It would be interesting to see what they suggest.

Royce

 

[TurboS10]

Cstraub, I know what you mean, and I have read some things that suggest that as well. However, I know of quiet a few guys running 240 to 250 range cams with good results. From what I have seen anyone wanting to make real power is running a good deal of duration. This guy is a good example : http://www.montygwilliams.com/. He is running over 250 duration and alot of lift. Most of the 5.0 guys are cranking around 8000 RPM to get those numbers. I guess with the small cubes and alot of boost it works without the large cam. I would be curious of any references you have for some reading material.

Royce, I appreciate the input and will post what I decide to do. I have not ruled anything out. I am on the road this week so I dont really have time during the day to call. Maybe Friday....

Thanks,

Chris

 

[Cstraub]

Chris,
Peak numbers or dyno queens are not impressive to me. You have moderate CID and a lower rpm to run. By increasing duration all you will do is narrow the useable powerband and slide it up the scale to the upper rpm range. This would be fine if you had a light car and Lenco.

You can make better useable power with a smaller shaft. I know, my customers do it everyday.

Chris

 

[TurboS10]

Okay, point taken. Do you have any engine specs/combos or products to look at? I would love to see some information. I am going by what I have seen so far.

Chris

 

[Cstraub]

Chris,
I don't. All my stuff is one off for engine builders. Performance in a Brown Box. I will do this, e-mail me the specifics of the engine and if you can send me a link on the heads to what Dart says they are flowing, I will point you in the right direction.

Chris
[email protected]

 

[TurboS10]

Cstraub,

Done.

Chris

 

[Cstraub]

Chris,
E-mail me and I will give you some cam spec's.

Chris

 

[67 Deuce 4 Me]

Cstraub, Where at in Tri Cities? I live in Johnson City.

 

[Cstraub]

Deuce,
You know where Zak's is then. I live out by Jay's Boat Dock off of Picken's Bridge.

Chris

 

[Max Keith]

cam selection

Over the past 40 some years of messing with engines, I have contacted several cam grinders about the advantages of roller cams. The main two advantages are more radical lifts with in a given degree of opening and higher lifts.
That asided, I have been told by them that unless you plan to run your engine well over 6500-7000 RPM on a constant basis, that a person is just about as well off to go with conventional solid lifters, as the gains in shorter profile roller cams arent that beneficial, to outweigh the expense. However, I have noticed a preferance of the auto manufacturers to have gone to roller cams in their hi performance models and engines, over the past 10-15 yrs.
I would say at this point, and the point that cam profiles have changed drastically over the past few years, that there would have to be some big benefits to going with a roller, regardless of durations and lifts, the down side being the cost. Personally, The addition of roller cams to any engine that I have built, would have put me well over budget.