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chevytruckman1987
I love my Chevy Chevette!
Posts: 5
Joined: 04/13
Posted: 04/05/13 06:24 PM

Hey everybody. I'm looking for some input. I'm working on a 1979 Chevy C10. I don't have much money to put into this project unfortunately so here's what I am going for. I want a weekend warrior that when you leave a stop light and push the pedal to the floor it slams you back in your seat to where you can't move!  Smile  I also want it to have that big cam loping sound! So far I have bought 249-K12-600-4 Cam kit from Jegs. I am hoping to be able to use my stock torque converter so I went with this cam hoping it would give me the loping exhaust sound without having to install a new torque converter. My buddy is going to give me an Edelbrock 650 CFM carb. I am thinking about buying the following: Edelbrock RPM Air-Gap Manifold; B&M 30228 - B&M Transpak (hard shift kit); and a set of Jeg's long tube headers. Later I want to put aluminum heads and install a manual transmission in the truck. Am I on the right track for what I am wanting? Are there any changes I should make for more torque without adding much more money to the build? Is the cam I bought a good size for what I am looking for? Thanks for input you can give me I am a newb and this is my first build.  

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68scott385
I mow my lawn and find Chevys
Posts: 1994
Joined: 10/09
Posted: 04/05/13 06:51 PM

How many miles does this motor have on it? A high milage motor is NOT a good place to start looking for performance.

What transmission do you have? th350 w/o lock up converter, th350 w/lock up converter, th400

Don't forget the rear gears. w/o od 3.42 is a good compromise, if it's strictly a weekend toy go 4.11,  w/od 3.73 is a good compromise

The rpm range for that cam is 2000-5800, without a looser than stock converter, something in the 2200+/- stall range, it'll likely be a dog until it gets to 2200rpm.  
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68scott385
I mow my lawn and find Chevys
Posts: 1994
Joined: 10/09
Posted: 04/05/13 07:00 PM

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=12-600-4&Category_Code=

This is a link to that cam at CompCams' website. They recommend 2000+ stall converter. There is also a link on that page to contact CompCams to get suggestions for a cam that fits your application(s)/desires.


For those that would like to know the specs of the cam, here's a link to that cam at Jeg's website.

http://www.jegs.com/i/Comp+Cams/249/K12-600-4/10002/-1  
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zman123
Everything in my driveway’s a Chevy
Posts: 537
Joined: 06/08
Posted: 04/05/13 07:24 PM

That's an awful big cam for a basically stock engine, if the heads are stock they are not the best, late 70's heads had 75cc combustion chambers and pretty low compression. If comp recommends a 2000+ RPM converter and you don't go to one you won't like it much. Just my humble opinion, If it were me, I'd make a plan and decide how you want to get there. Maybe get an engine from a junk yard and build it the way you want as you can afford it, the guys on this forum will help. There is a lot of knowlege here. Be patient and do it the right way the first time. good luck with yourr project.  

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chevytruckman1987
I love my Chevy Chevette!
Posts: 5
Joined: 04/13
Posted: 04/05/13 08:29 PM

Thanks zman123 I'm going to need all the luck I can get! Lol I have to pull the engine anyway so I guess I could go ahead and put in a stall converter. 68scott385 The truck has a TH350 W/O Lock up converter. I'm not sure on the mileage of the engine. The original engine that came with the truck was a diesel 350 and someone swapped it out for this engine. Maybe I should just get a new block and do a complete engine build. It just stinks because I really would like to get it finished so I can use it this summer. It's been sitting in my driveway for 2 years now every day I come home from work dreaming of the day she's on the road. And if I do a complete engine build it is going to take me a a year or two to get enough money to do it.  

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zman123
Everything in my driveway’s a Chevy
Posts: 537
Joined: 06/08
Posted: 04/06/13 07:51 AM

What is the old saying? Patience is virtue. I think you will be much happier in the long run if you go step by step and get a final product you will be proud of.  

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68scott385
I mow my lawn and find Chevys
Posts: 1994
Joined: 10/09
Posted: 04/06/13 08:21 AM

That cam probalby needs 9.5:1cr to work well. It will work with less compression but not to its potential and will be less fun to drive than the stock motor you have now. The stock motor probably has a factory advertised cr of 8.5:1. If the motor was measured it would likely be closer to 7.8:1.

First things first, we need to back up a little and establish exactly what you have to work with. In front of the right cylinder head is a flat surface with a series of alpha-numeric codes. There is a three letter code at the end of one series. Post those three letters. You may have to use a wire brush or something similar to clean the surface enough to accurately read what's there. It would also be very helpful to know what heads you have. You'll have to remove a valve cover to see the casting numbers. The casting number is a 6 to 8 digit number cast into the top of the heads. Sometimes they are difficult to read. Post those numbers too.

Once we know what you have to work with we can give better advice on the direction to take to get to your end goal.

Pictures would be nice too.  
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Dave632
I mow my lawn and find Chevys
Posts: 2253
Joined: 07/08
Posted: 04/06/13 11:26 AM

At first we all tend to go overboard with too big a cam, carb etc.
I would recommend a milder cam unless you are planning on a higher stall converter. Better heads are going to be necessary if you want to get the advantage of the long duration cam. A higher compression, which could be accomplished with a head with a smaller combustion chamber, should also be used.  
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chevytruckman1987
I love my Chevy Chevette!
Posts: 5
Joined: 04/13
Posted: 04/06/13 03:35 PM

@68scott385 The only numbers I could find on the heads were these: k302 ; 8998993 ; GM29; and 21. Any of those numbers mean anything? Thanks to everybody for the help so far!!! I will try to get some pictures soon.  

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pepsi1
I mow my lawn and find Chevys
Posts: 1718
Joined: 09/11
Posted: 04/06/13 04:12 PM

In 1972-73 they  the 993 head was installed on 307 and 350 engines.

Current: They are installed on all crate engines. they are all 75cc combustion chamber. Not really good horse pore heads.

Bob  

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68scott385
I mow my lawn and find Chevys
Posts: 1994
Joined: 10/09
Posted: 04/06/13 04:18 PM

3998993 307/350 68-79 1.71/1.50 1.94/1.50 76cc

The casting numbers are 3998993, there are no sb casting numbers that start with an eight. They were used on 307 & 350 blocks with 1.71/1.50 or 1.94/1.50 valves, respectively. All heads of those casting numbers were 76cc large chamber heads. That means that you'll have a hard time getting compression using those heads. It can be done with high dome pistons but the high domes are good for flame travel. It is preferable to us a smaller chamber head and piston with a flat top or small dish.


The big question now is what block atre those heads bolted to? You might have to take the alternator off to get to the flat block suface in front of the right head.  
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chevytruckman1987
I love my Chevy Chevette!
Posts: 5
Joined: 04/13
Posted: 04/06/13 05:09 PM

Okay  

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chevytruckman1987
I love my Chevy Chevette!
Posts: 5
Joined: 04/13
Posted: 04/06/13 05:20 PM

Hmmm this is kind of interesting. I found a tag on the engine that says Aaron's Automotive Products Springfield, MO ; Serial # 151256 and unfortunately it looks like the part # is completely worn off or was never stamped on the tag. I will try to clean the engine better to see if I can find any other numbers tomorrow. I'm thinking this might be just a cheap old crate engine....?  

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zman123
Everything in my driveway’s a Chevy
Posts: 537
Joined: 06/08
Posted: 04/06/13 07:34 PM

With that tag number you might be able to track down what exactly was done to that engine, and when it was rebuilt..if they keep records like that.  

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