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Bare with me this is my first post. I have a stock 350 that I want to build. We got it from a family member who has multiple sitting in his shed. But we want to run the comp magnum 292 cam in it. We are going to match it with 64cc 200cc Heads. On top of that we are going to run a performer rpm intake with 650cc Edelbrock carb. We will also be running a 3000 stall with 4.10 posi.
My question is will this setup work well or end up being a dog? I am hoping 400hp. Any help will be greatly appreciated. Thanks in advance.
 

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The comp Magnum 292 244/244 is a big cam and 3500 stall may be more appropriate, because that's about where it starts pulling hard... also it would like a Holley 750 carb. and Victor Jr./Victor intake better... setup valve springs for 3500 - 7000 RPMs... aim for 450 - 500 HP... 4.56 gear... sticky tires... all forged rotating assembly... 10.5 - 11.0:1... is this mainly for strip/race use?
 

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Bare with me this is my first post. I have a stock 350 that I want to build. We got it from a family member who has multiple sitting in his shed. But we want to run the comp magnum 292 cam in it. We are going to match it with 64cc 200cc Heads. On top of that we are going to run a performer rpm intake with 650cc Edelbrock carb. We will also be running a 3000 stall with 4.10 posi.
My question is will this setup work well or end up being a dog? I am hoping 400hp. Any help will be greatly appreciated. Thanks in advance.
From the factory stock 350's come from 145 hp to 370 hp, needless to say the internals especially the short block are a lot different so you need to know what you're starting from. Since GM puts a lot of the compression ratio into the piston, simply changing heads may or may-not make much if any difference in compression ratio. Big and the bigger they are the more compression they need and the Comp 292 cam likes a lot of compression.

You can find out what the engine is by referencing the build code on the flat just below and ahead of the passenger side head. Other indicators are the casting numbers for the block, on the bellhousing flange, drivers side, and the heads, on the head facing up with the rocker cover removed.

Building an engine today is very different path than the good old days since compression is limited by fuel that is available. For the street this leads to shorter durations with more and faster lift rates wider LSAs and less ramp time leading to and away from the lobe. This vastly improves power especially with modern chamber heads. Getting 400 hp from a 350 today is easy with Vortec style heads, 9.5 to 1 compression, a Comp XE268H cam, Edlebrock Performer RPM intake, a 750 carb, 1.6 ratio roller rockers on 7/16ths studs, and 1-3/4 dia long tube headers with a 3 inch dia collector.

Bogie
 

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Bare with me this is my first post. I have a stock 350 that I want to build. We got it from a family member who has multiple sitting in his shed. But we want to run the comp magnum 292 cam in it. We are going to match it with 64cc 200cc Heads. On top of that we are going to run a performer rpm intake with 650cc Edelbrock carb. We will also be running a 3000 stall with 4.10 posi.
My question is will this setup work well or end up being a dog? I am hoping 400hp. Any help will be greatly appreciated. Thanks in advance.
The carb will not get it done - need larger. A better intake wouldn't hurt either Buzz's recommendation is a winner. Your 64cc 200cc heads ought to be aluminum and flow more than 250 cfm at .550 lift and you'll need darn near 11:1 compression to sneak by on pump gas. If the heads aren't aluminum, then you'll need to drop the compression.
 

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sounds like a less than good combo.

Don't ever build an engine around a camshaft!

Determine what you need to get your performance specs, The research the heads first! What rpm range do you need your engine to perform in. What exactly are you putting this engine into?
Your transmission and diff need to match the vehicle and its purpose. Start with the car,,,
 

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Discussion Starter #6
The engine will be going into a 83 c10. It has 700r4 transmission with a shift kit. The build is going to be for drag racing and maybe some trips to the drift pit. So what I’m hearing is definitely a bigger carb and a new intake woud be a necessity.
 

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If you seriously want to drift a pick up??? You need some torque at a lower rpm.

I would start with a minimum of a 540, turbo 400,3.9 to 4.1 gears

tune the engine to make peak power 5500 rpm or lower.
600 pounds torque of more.
drifting is more than slipping in corners, you want to blaze the tires
 

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If you seriously want to drift a pick up??? You need some torque at a lower rpm.

I would start with a minimum of a 540, turbo 400,3.9 to 4.1 gears

tune the engine to make peak power 5500 rpm or lower.
600 pounds torque of more.
drifting is more than slipping in corners, you want to blaze the tires
With that being said any recommendations on how to build a 350 that would be sufficient for that?
 

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The engine will be going into a 83 c10. It has 700r4 transmission with a shift kit. The build is going to be for drag racing and maybe some trips to the drift pit. So what I’m hearing is definitely a bigger carb and a new intake woud be a necessity.
Performer RPM will be the better intake considering your vehicle goals, but it does need the bigger carb.
 

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If you plan to drag race?
DETERMINE:
how fast you want to go
how much your truck weighs
How many horses you require


after that draft engine plan
 

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Discussion Starter #12
If you plan to drag race?
DETERMINE:
how fast you want to go
how much your truck weighs
How many horses you require


after that draft engine plan
For drag racing I would like to run around high 12 low 13s. Not planning on a 10sec truck. The truck weighs 4000lbs currently. I will be gutting bed and some other misc items to cut it to 3500 eventually.
 

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With that being said any recommendations on how to build a 350 that would be sufficient for that?
Deciding straight off the bat to build it as a 383 stroker would be the first thing to do, forget all about a little 350 cube deal. cost won't be much different than rebuilding and remachining all the stock stuff, so it makes more sense to do a stroker.

The Comp 292 Magnum cam is not likely to be the best choice in either engine size for this job.
 

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The engine will be going into a 83 c10. It has 700r4 transmission with a shift kit. The build is going to be for drag racing and maybe some trips to the drift pit. So what I’m hearing is definitely a bigger carb and a new intake woud be a necessity.
You should also be hearing 'all forged internals' if the 350 you have doesn't already have that stuff... 1970 LT1 350's do... and 4:56 rear to drag race a full size truck... maybe even a 4.88 or 5.13 rear depending on rear tire diameter choice...

1.6, 1.65, or 1.7 rocker arms to get the lift higher on the Comp 292 cam...

IF stroking for a full size truck, consider a 400" stroker kit... 220 - 235 cc heads...
 

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The engine will be going into a 83 c10. It has 700r4 transmission with a shift kit. The build is going to be for drag racing and maybe some trips to the drift pit.
For drag racing I would like to run around high 12 low 13s. Not planning on a 10sec truck. The truck weighs 4000lbs currently. I will be gutting bed and some other misc items to cut it to 3500 eventually.
Paradox alert - a 12-13 sec truck is not going to drift anywhere.

You need more power x 2 at a minimum. Having a plan to later add a supercharger or turbo is GREAT one. And most all of us will understand not having the funds to build a 700-900 HP motor right out of the gate.

As mentioned, build the motor NA to handle the boost down the road. That means forged slugs, decent aftermarket rods, forged crank, aluminum heads, and keep the compression in the 9:1 area. You can get by with more compression NA, but the forced induction setup will be much easier tune (larger tuning window) at 8.5-9:1. You should plan on a cam change when the forced induction comes along.

And no need to go any smaller than a 383.
 

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Paradox alert - a 12-13 sec truck is not going to drift anywhere.

As mentioned, build the motor NA to handle the boost down the road. ...but the forced induction setup will be much easier tune (larger tuning window) at 8.5-9:1.
A 13 second vehicle can drift... but drifting is very wasteful of tires and money...

Strong drag engine and boost engine will need different pistons...
.
 

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My drifting customers that compete...are all 600+hp LS transplant guys. But; you can have fun with less, you just need way more gearing to get the wheel speed up. Wasteful of tires and money? One could argue that of any competitive racing endeavor. We shouldn't cast dispersion upon what others do in the spirit of hotrodding, racing and the pursuit of fun. If it ain't hurting you, don't hinder them.
 

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Putting Drifting into the picture means you will also need to be looking at a very good oil pan and windage tray set-up, nothing cheap will be good enough.

Quickly changing G forces wreaks havoc with oil control, anyone serious on drifting is using some type of remote belt-driven oil pump. (With the exception of the LS engine guys).

This is sounding more and more like 5.3 LS engine/Turbo swap candidate rather than the old SBC deal. The SBC is going to cost you more in the end.
 

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On top of that we are going to run a performer rpm intake
At 8:50 and 11:00 in this video they discuss the amount of power lost using a dual plane performer RPM-type intake manifold on an engine with a 236/242 cam:


How much of your parts list do you already have? are you on a tight budget?

Don't get us wrong, your original plan engine will run strong, and could be a little delicate if using mostly stock parts, but some of it can be tweaked better as we mentioned for about the same money while putting it together... or as your budget allows later... for items that can't be sold now to get funds for more appropriate parts...

I remember back in the day taking off in my stock GTO and shifting through all the gears and moving off in 4th gear with both rear tires burning... but... WOW !!! ... As vehicle speed got up around 50 MPH, unexpected, powerful, squirrelly, violent, dangerous forces came into play and I had to let off to get my body and the car back under control !!!

Some 1.6 rocker arms:

https://www.summitracing.com/parts/sum-g6801

Dual quad tunnel ram:

https://www.summitracing.com/parts/cmb-03-0184/overview
.
 
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