Projects Chevy 350 65’ C10

Hey so I started a thread from a 250-350 swap that was just completed a week ago. Thank you too everyone that helped out on that and I have pictures here with some videos. Just waiting on radiator fan and downpipes. Anyways I’m wondering how involved a cam swap would get and if it’s worth it. I want to have a more choppy idle and I don’t want to do a rebuild. I’m looking somehwere in the 500-700 for everything so cam, pushrods, new seals, etc. Was wondering if anyone had good suggestions

 

I actually just found this cam it sounds great. The motor only has a couple thousand miles on it and it runs smoothly so I don’t know if I’d have to upgrade anything to run this cam
COMP Cams K12-212-2 Magnum 224/224 Hydraulic Flat Cam K-Kit for Chevrolet Small Block https://a.co/d/1zlugy0

 

My only suggestion is you should have swapped cams before the engine was in place.

 

Yep, if I was doing it, I would pull the engine. Much easier to do as far as getting the pan gasket sealed up with the engine upside down. By the time it is apart enough to swap the cam, there isn’t much left to just pull the engine back out. So, I would likely leave it as-is if I had just put it in.

 

What is your compression ratio , what pistons , what cylinder heads , what's the quench measurement , what intake & carb , what trans , what stall converter , what rear gear ratio , what is your primary use for the truck ?

 

i have seen that cam used in a lot of stock engines, it's ok and runs better then stock fore sure. but i think you would be better with the comp cams 268 high energy or the 270 magnum for your choice. i have a 350 with dish pistons and open chamber heads, the heads have had a lot of port work. i installed a 292 magnum cam (what i had), it will run, but it will also burn your eyes with the raw gas out the exhaust, it needs more compression fore sure.

 

If you are happy with the way it runs, a cam change for a choppy idle may not be a great idea. That cam is 230 at .050 and would really need a higher stall speed converter to work correctly. I don’t know what your compression ratio is, but in an 8.5 to 1 engine, that is a lot of cam.

 

That cam has an advertised duration of 280º. That is a lot for a strictly street vehicle.

It will take away from a fair amount of the bottom-end torque, and move it up into the higher RPM range.

That is not the best thing, especially if you are planning on driving this daily. Not that this thing is going to get great mileage anyways, but that cam will cause you to have to lay into the throttle more at low RPMs to get it moving. You will be using more fuel as a result. It looks like you might be in coastal California. Fuel ain't cheap here. Losing 5mpg for sound will add up quickly, and it won't stop adding.

Sounding cool is one thing, having a vehicle that is comfortable to drive anytime, anywhere, if a far bigger thing.

I might look at muffler choices to improve the sound.

I'd get everything else settled, and drive it until Summer. See how you like it the way that it is.

 

He has a manual transmission.

 

Whoops, I’m sorry, I kinda overlooked that.

 

Buy or borrow a compression gauge.

Disconnect the coil power wire. Pull all of the plugs, and prop the throttle blades open with a large screwdriver.

Test the compression.

In this case, you are not looking to see what the condition of the engine is. You need the number.

Take that number, let's imagine that it averages 135psi across all cylinders.

Divide that 135 by 14.7 (atmospheric pressure at sea level, assuming you are about that).

That gives you 9.18.

We're the 135 number correct, and you are at or near sea level, then that is about your compression ratio.

This number, of course, is not truly accurate, as it is subject to a number of other conditions, far too numerous and detailed to cover here.

The real running dynamic compression ratio will be 10 - 15% less than that, so more like 7.8 - 8.62:1.

This plays a HUGE role in choosing a cam.

I will bet good money that there are more people running the wrong cam in their engine than there are the right one.

What town/city are you in? I will look up the average elevation.

 

Sounds like ya lookin for one of those VanHalen “ Hot for Teacher” cams.

 

This thread will no doubt have a very predictable sequel!

 

I always was thinking a fuel car when I hear the drums. But good meme/pic/words. Lol

 

Yes, where are you at? I may have a cam for you if your interested.

 

Antelope Valley CA

 

Quartz Hill Area CA

 

I just ordered 2.5” Cherry bombs that are 24” long for my mufflers and I’m getting like 9mpg at the moment lol. I’m not super concerned with gas mileage because my straight 6 got like 7. However I don’t want it to be nothing. But I don’t daily it I drive it once or twice a week

 

That MPG isn’t right
Edit: I should have added not good.

 

Antelope Valley goes from about 2,100 to 3,000 feet above sea level. For simplicity sake, we will need to split the difference at 2,550 feet. Also for simplicity sake we will need to call it a clear and dry day, at 60ºF.

With those standards set, atmospheric pressure where you are is approximately 13.40psi.

Take your compression readings and divide them by 13.40 and you will get an approximation of your compression ratio, with the above and previously mentioned caveats.

 

That milage is already terrible. The inline-6 should have been in the mid-teens, with the V8, if a crate or stock engine, should be in the low teens, each in mixed driving.

I am willing to wager that your spark plugs are sooty and black.

About the best tool that I can say that I own, and the single biggest way to prove, with data, in a concrete fashion to customers that their vehicle is in a very poor state of tune is a wideband oxygen sensor.

Every vehicle that leaves my shop has a bung welded into the exhaust system for one, cars, trucks, motorcycles, motorhomes, boats, whatever. Naturally aspirated, turbocharged, and supercharged.

I have been able to take vehicles that will make your eyes water if you drive behind them, fouling plugs in 150-miles, and turn them out getting over 20mpg, with more power and better acceleration.

I tuned a 270 Red Ram Hemi in a very light Model T track roadster last year. The owner has been driving it quite a bit, too. We still have no idea what the mileage increase was because he has yet to have to refill the fuel tank!

Prior to this, he would burn half-a-tank just getting it to my shop.

I went as far as to call it terrible.

 

What of the history of this engine do you know?

Is it stock? Rebuilt? Modified? Crate?

If it is a stock engine, or a stock rebuild, can you get a picture of the pad on the front of the block that sticks out in front of the passenger-side cylinder head?

The width will vary by year, and some of the pads have a partial VIN stamped on them.

The key code on these should start with a letter, F, H, K, M, S, T, V, indicating the engine plant.

Then two-digit month, followed by two-digit day

After that you will find the important info, the Engine Suffix Code. That will indicate the vehicle-of-origin, and possibly the current configuration. That may be a two, or three letter code. If it is a three-letter code that starts with a T, then the block, at-least, started out life in a truck.

The pad looks like this, and varies a bit era:

-or-

 

Gimpy, that is a super cool way to get an idea of compression ratio. Between you and several other guys here, I always lean something for you guys. Thanks for sharing your experience and knowledge.

 

You're welcome!

It is by no means a perfect methodology, as it is influenced by a few dozen variables, but it can distinguish a seller's claim of 11.25:1 compression from an 8.5:1 reality.

 

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You are to far away for me to help you install it, but the cam I have is 300 advertised duration, 224, 224 @ .050, .436 lift, on a 108 LSA. It takes a little tuning in the carb to Idle right. It is used, about 5000 miles was broken in properly and is not junk. It is a 23 year old P.A.W grind, and the lifters are in order. There are lots of knowledgeable people on this thread, who can advise you on the merits of this cam good and bad. I have a home for it, and am not out for money so no sweat if you don't want it, but I will offer this to you, for the cost of shipping only, about 25 bucks I think . It sounds badass, an ran hard in my 327 4 speed ElCamino, but ,like I said needed carb tuning to be right.

 

I run a 230-230 @.050" with a .490 lift and a 110* LSA in a 370 cu in engine. It's lumpy but in my car [prolly 500-800 lbs lighter than your pickup] it's easy to drive [4 speed with 3.10 gears and 30" tires], starts easily, doesn't overheat.
I once used a 302 degree Crane cam in a 327 in my 57 Bel Air with a 4 speed and rear gear that was unknown but waaaaaaay too high! It was a pig 'till it got to about 4500 RPM and then it was insane!

 

Yeah the mileage is terrible however the timing is off, the carb hasn’t been tuned, and there’s no exhaust just straight headers so everything’s playing against it. I cruise 55mph at about 2000 rpm. Spark plugs are brand new

 

From what I researched online this came out of a 69-73’ Camaro that’s LA built? Said 2/4 bolt rear main and then it makes 250-300 horsepower. Engine has about 10,000 miles and has never been rebuilt. Was swapped into a 73 Monza then pulled and sat for 15 years

 

I’ll have to look tomorrow after work but it doesn’t seem like there’s any stamp on there

 

Hey man if you want to ship that thing for $25 I’d like to just have it for a swap or display to be honest. I’d like to put it in of course though