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jake Newbie
Joined: 28 Sep 2010 Posts: 3
210.34 points
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Posted: Tue Sep 28, 2010 4:38 am Post subject: I need some help with my small block rebuild please!!! |
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I started this project as a simple rebuild for my 89 chevy 4x4 and it has since went haywire. I've rebuilt several engines back to stock specs but this went from stock to mis matched parts, I started with an 1989 2bolt 350 with standard heads but now I have an 86-94 4bolt 350 block bored 40 over and a set of 906 vortec roller heads (that I bought for $50 ready to bolt on) since my old stock heads were both cracked in the exhaust ports. My problem is that I want to build it for towing and still be able to run my stock TBI or at least close to stock. My pistons are not performance pistons just 40 over badger replacements that I had left over from a previous build. I am wanting to run a roller cam to match the heads but can't seem to find one in the rpm range for my application at a reasonable price, any suggestions for where to go from here? |
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clay Moderator

Joined: 24 Nov 2002 Posts: 3209 Location: South Carolina 318129.23 points
1972 Chevrolet Nova
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Posted: Tue Sep 28, 2010 10:52 am Post subject: |
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One option is to run the stock cam from a Vortec engine. I have done a stock Vortec with headers and a Performer intake with a 600 Edelbrock carb and it was a pretty torquey package. You could add 1.6 rockers as a cheap item that would help. You are limited on lift with the Vortec heads so a lot of the hydraulic rollers with any sort of duration will exceed the lift limit of the heads (about 0.475"). Elgin makes a hydraulic roller that would work. They have 2 actually. 1st has 202* - 212* at 0.050 with 0.437 / 0.462 lift on a 112* seperation - rpm range idle to 4600. Part # is E1040 from Competition Products. Price is $199. Other choice is 210* - 215* at 0.050 with 0.462 / 0.470 lift on a 110 seperation - rpm range is 1500 - 5200. Part # is E1136. Price is $182. If you run either of these you would have to stick with the factory rocker ratio to not get into too much lift. You could actually check your particular heads to see exactly how much lift they could handle - the 0.475" is just the generally accepted rule. Clay _________________ I have done so much with so little for so long, I can now do anything with nothing. |
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jake Newbie
Joined: 28 Sep 2010 Posts: 3
210.34 points
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Posted: Tue Sep 28, 2010 12:58 pm Post subject: |
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Thanks for the suggestions, I'll have my guy at the machine shop check the lift of my heads and I'll let you know what I find out. The only thing I know about the heads are they came off of a goodwrench performance motor and are drilled for the vortec intake and for carb intakes, I'm going to have to do some work to my TBI intake so I can bolt it on. I don't know what the rocker ratio is for the rockers that came with the heads I just know they are self aligning. They also have the single angle valves with hardened vale seats. |
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Agoetz2005 Newbie
Joined: 21 Aug 2010 Posts: 9 Location: Spring Hill, TN 302.94 points
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Posted: Wed Oct 13, 2010 3:11 pm Post subject: |
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I have heard going with 787 retainers, and LS6 Valve Springs can get you up in the .500 lift range with the vortecs without any work. |
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jake Newbie
Joined: 28 Sep 2010 Posts: 3
210.34 points
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Posted: Wed Oct 13, 2010 3:51 pm Post subject: |
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I'm still not sure exactly what springs I have but my guy at the machine shop said that they will handle up to a .600 lift before binding, they are deffinetly not stock springs. |
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