I have a cam and would like an opinion on if it should be used with my engine.
Here are the cam specs.

Valve Lift:
int- 420
exh-443

Lobe Centers:
int- 107
exh- 117

.050 Duration
int- 204
exh- 214

HYD. flat tappet

other info... .050 timing, BTC-5, ABC-29, BBC-44 and ATC-10

Now for the engine...
406 SBC with 5.7 rod Scat crank to match and Kieth Black dish pistons
part number ZKB-147-040,
Dart Iron Eagle 72cc with 2.02/1.6 valves
Professional products dual plane intake
Headers
Holly 750 double pumper

This engine will be installed into a 78 Chevy 4X4 with stock converter and 3:73 gears with 33" tires.

Thanks in advance for any help...

How about a Comp Cams 270H? Hyd, biggest w/stock convertor, Mild --rough idle..Cost $95..Sell it for $65 + the ride from 63016..Brand New, Still in wrapper..Let me know...

where is STL are you located?

Do you live in city, North, South or West county?

Can you tell me more about the cam or maybe actual part number so I can look at those specs.?

You can PM me..

I am interested.

John

You may need a small base-circle cam with 5.7 rods...depends on what type of rods you are using. That's why the 400s used 5.565" rods with a standard base-circle cam from the factory.

The cam I already have fits without hitting the rods, I just want to make sure it's the cam I need before I go ahead and install.
This cam was give to me and specs. are diffrent from what I've seen.
BTW, its an Elgin cam.

You can have the amchine shop clearance the rods before balancing.

That cam is too small for a 400. It isn't worth running a 400 with that cam. You would be better off with a 350 at that point.

You want at least .060" more lift. The duration could stand at least another 5 to 10 degrees if not more.

QUOTE: "This engine will be installed into a 78 Chevy 4X4 with stock converter and 3:73 gears with 33" tires."

Take note here his gearing is equivalent to around a 3.08 rear gear with stock tires, and in a heavy truck is going to be a slug with too big a cam. How big are the intake runners in the heads? The cam he listed is one we use all the time as an RV grind, and although it is no high RPM screamer it has nice torque which is what he really needs with the combo. If he does a gear ratio change and adds about a 2500 stall then he can look at a larger cam. Remember, even the mighty 454 had less lift and duration than that one...
Torque is the answer, don't overcam

QUOTE: "This engine will be installed into a 78 Chevy 4X4 with stock converter and 3:73 gears with 33" tires."

Take note here his gearing is equivalent to around a 3.08 rear gear with stock tires, and in a heavy truck is going to be a slug with too big a cam. How big are the intake runners in the heads? The cam he listed is one we use all the time as an RV grind, and although it is no high RPM screamer it has nice torque which is what he really needs with the combo. If he does a gear ratio change and adds about a 2500 stall then he can look at a larger cam. Remember, even the mighty 454 had less lift and duration than that one...
Torque is the answer, don't overcam

Intake runners are 200cc.
I'm building the truck with the intention of pulling our race car trailer and my son will drive it school (glad its not far).
Thanks for the info.

John

No problem John, hope it works very well for you.

Imho, rust said it well!

That little bitty Performer cam will do fine with 3.73's and 33" tires!!

Sure, it will probably sign off at 4,000 rpm, but what's that 85 mph??

pdq67

It'll be ok.
But IMHO I would go just a tad bigger.Even the Edelbrock Performer cam for the 400 is bigger.It had an even 214 duration at .050.

Back in the day I had a 383 with the CompCams 268HE (268 218 454 110) and it pulled like a Muth'a on the bottom, but no top end.It was all done by about 5200-5500.The added cubes of a 400 would only make it that much more of a torque oriented grind.I wouldn't go that big if it's a tow rig, but I'd certainly look for something with an intake duration figure of 210-214 at .050.

Thanks everyone for all the info! This has got me and my sons talking and debating is the best part.

Imho, rust said it well!

That little bitty Performer cam will do fine with 3.73's and 33" tires!!

Sure, it will probably sign off at 4,000 rpm, but what's that 85 mph??

pdq67

more like 110mph, and I sure as heck wouldn't want to be in a lifted, 5000 pound brick when she hit's the top of that torque curve. ;) The 77 is the old solid front 4x4 axle, and that square face is about as aerodynamic as an apartment complex. These things get pretty crazy when you get up there in mph.
I'd pay close attention to measured ACTUAL compression, keep it WELL UNDER 10:1 and I think you'll have a torque monster that will pull the horns right off the devil himself :happy: But you really need to take a close look at what compression is going to be. I played with the configuration and just depending on what deck, and what cc dish you have, you could be anywhere from 8.2 to 9.9:1. Myself, I think it's going to be a sweet tow vehicle with the cam you have and set compression right at 9.0:1. Just be cautious and measure EVERYTHING!!! Is this a "D" dish or a full dish piston? A lot of the KB rebuilder pistons set the piston an extra 0.020+ down the hole. Know what the deck clearance MEASURES, know the cc of the dish, and pay attention to what head gasket. All of these things can make a poor quench that is going to make it unhappy with poor fuel and when a load is behind it, or it can make compression so low that were making a very inefficient motor.

Info I found about the KB piston,
compression ratio is 9.1 with 76cc chamber and 10.2 with a 64cc chamber. Mine is 72cc Dart Iron Eagle.
18cc/D-cup
Effective head volume: 18cc
Bore is 4.125
Stroke is 3.75
Rod is 5.7"
Comp Ht: 1.433
I dont want to race the truck... I just want to pull a heavy (4000lb) race car on a heavy (1500lb) trailer. I have been doing allot of thinking and have been really wondering if were not better to just put a big block 454 in the truck.
I really didnt want to do that because it is an all original one owner truck.The truck is in really good condition so I didnt want to change much although I am going to use it one way or another.

Compression ratio should be 9:1 with .017" deck and a .041" head gasket, or 9.3:1 if the block was zero decked. That compression may need premium fuel when towing but will net some decent torque numbers, potentially better than the 454 you're considering. After owning a 454 in my old truck and now a 6L in my 2004 extra cab long box (not really a fair comparison) I'll stick with small blocks thanks, much more versatile and a little better on fuel consumption.

Well, I already have the crank rods and pistons installed in the block so I wont give up yet. I have been just a little worried that I would not be happy with the performance. I have already re-built the th-350 and transfer case so I cant give up yet. I'll continue with the plan and post the results. I'm sure it'll be fine after everything thats been discussed. After all... should be almost big block power in a small package.... Thanks

Marv,

My big headed B-i-L took me out for a short ride in his new back then '77 H-D, Gimmy 3/4 ton Fleetside long bed that he'd just put big slotted mags on along with big tires!! Granny tranny and all!!!

He roll's us around a curve at 70+ and say's, Oh, she's a bit top heavy at speed and I thought to myself, you crazy SOB!! Let me outta here fast!!

And both him and my older Sister bragged about how good a gas mileage it got, like 16+ and years and years later he finally came clean and said the big SOB never got better than 8 mpg loaded or unloaded all those years!!

pdq67