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need suggestions for build

 
thatguy1559
I love my Chevy Chevette!
Posts: 1
Joined: 11/12
Posted: 11/06/12 11:40 AM

hey i have a 98 5.7 vortec that i need help deciding how to build it. I've been recently challenged by a couple of mustang lovers that i cant build a motor to out run them at all, but i am determined to win this. i've been researching for a while on how to build it and what to do. at the time i cant go all outragious with this build just yet. so please lend your knowledge and advice so i can win one for the chevy team  

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Dave632
I mow my lawn and find Chevys
Posts: 2253
Joined: 07/08
Posted: 11/06/12 12:55 PM

It is a matter of knowledge and money.
The heads on those motors are fair for making power.
If you are on a strict budget I would put a decent cam, intake, carb and headers on it and you should be able to beat most stock Mustangs.
If you are running against highly Modified Mustangs you will be in trouble as it will cost more money to be competitive there. I have no problem with Fords as they are an American car.
I personally hate the Asian cars. I would go out of my way to race against any of them. They are generally pretty pathetic but once a while one runs good. Most of them would not run against me even when I ran motor against all the nitrous they could run.  
[[SUPPORT AMERICAN CARS, STOMP A RICE CAR TODAY.]]

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thatguy901
I love my Chevy Chevette!
Posts: 6
Joined: 11/12
Posted: 11/06/12 03:12 PM

Somehow my other account. Won't work but they are modified one is running a turbo on 6 to 10 psi and the other is running a stroked 351w. I don't mind spending a little extra money to get my point across  

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pepsi1
I mow my lawn and find Chevys
Posts: 1718
Joined: 09/11
Posted: 11/06/12 03:58 PM

Like Dave said induction is the key to Horse Power. The parts need to match and get Your rear gear to keep you in the power band you'll beat them.  

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thatguy901
I love my Chevy Chevette!
Posts: 6
Joined: 11/12
Posted: 11/06/12 09:03 PM

I'm still confused on the head set up that would do best cause I thinking to just bore not stroke the motor. But. I don't know if I should use the vortec heads or not cause I know i'll probably end up running a 4.10 rear gear.  

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redneckjoe69
I mow my lawn and find Chevys
Posts: 2337
Joined: 03/10
Posted: 11/07/12 07:53 AM

if they are stock vortecs, you wont be able to run much above .420-.450 lift safely before coil-bind.   you can take them to a machine shop and have the guides machined though.   just my 2 cents.     somebody had an article/pictures/diagram about this.    if racing, i would get screw-in studs also.   flat-top pistons would be another good addition, along with the other suggestions above.  

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Pontiacman2
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Posts: 8956
Joined: 09/08
Posted: 11/07/12 08:44 AM

This leads us to valve springs, which require the most attention in a performance application.If this is an OEM iron head 062 or 906, GM designed the valve guide to also serve as the inside diameter (id) locating device for the valve springs. The guide?s large diameter acts like a sleeve that keeps the single-wire valve spring located >> properly. The guide is also machined at the top to mount a positive-style, 0.560-inch-diameter valve-guide seal. All of this conspires to limit total valve lift to a safe figure between 0.420 and 0.430 inch. The limitation is the clearance between the bottom of the retainer and the top of the valve-guide seal.

Accommodating more valve lift requires modifications to the valvespring seat and valve-guide areas of the head. The best route is to increase the spring-seat diameter from the standard 1.25 inches to 1.440 inches. Both Comp and Crane offer tools that use a valve-guide arbor to position the cutter. The Comp Cams cutter increases the spring-seat diameter while simultaneously reducing the outside diameter (od) of the guide boss. The Crane tool also cuts the valve-guide-seal diameter at the same time. Comp sells a separate tool that cuts a new guide seal and reduces the guide height to create additional retainer-to-seal clearance. Both cutters machine the top of the guide down to a 0.530-inch diameter, which is the standard size for positive-type aftermarket seals. This requires purchasing new valve-guide seals, since the factory uses a 0.560-inch guide to locate the seals. Another way to go is to have a machine shop cut the guide boss diameter to around 0.760 inch and reduce the seal height and use either the Crane H-11 tool steel spring (PN 99846) or the Comp spring (PN 981).

Once these machining operations have been completed, you have the choice of several aftermarket valve springs to match your cam profile. These machining operations will produce enough clearance to allow between 0.525- and 0.550-inch valve lift before running into valve spring coil-bind. Given a 1.440-inch valve spring seat diameter, Comp and Crane offer several single and dual springs that will work with the stock valves.  
Pontiacman2
Pontiacman2

Professional Hi-performance engine builder

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tuffnuff
Moderator
Posts: 7841
Joined: 12/09
Posted: 11/07/12 12:45 PM

+1 Pman
While you're at it, get the bigger 2.02" intake valves installed in those Vortecs.

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

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thatguy901
I love my Chevy Chevette!
Posts: 6
Joined: 11/12
Posted: 11/07/12 12:47 PM

Would it be easier to just buy after market heads or getting the stock heads machined  

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68scott385
I mow my lawn and find Chevys
Posts: 1994
Joined: 10/09
Posted: 11/07/12 02:00 PM

For the money invested doing a valve job, etc. to stock heads, even Vortecs, you could spend a few hundred more and have better flowing aluminum heads. JMO  
68scott385 68scott385 68scott385

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pepsi1
I mow my lawn and find Chevys
Posts: 1718
Joined: 09/11
Posted: 11/07/12 02:46 PM

Yeah if you intend to do any more modifacations to your engine. The Vortec heads are limited all around. Invest in a an aluminum head. around 200cc to 210cc or smaller if you have a small cam. If you decide to go aluminum heads, talk to a tech person.

Bob  

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thatguy901
I love my Chevy Chevette!
Posts: 6
Joined: 11/12
Posted: 11/07/12 04:00 PM

Are there any suggestions on brand  

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redneckjoe69
I mow my lawn and find Chevys
Posts: 2337
Joined: 03/10
Posted: 11/07/12 04:24 PM

can you give these guys a budget for heads?
   for the entire engine?
    rear gears?
     tranny?    
      car?
       tires?

   the more info the better.   lets get into details.  the motor alone is not always gonna win, its a total package.   be honest with your budget & youll get lots of help/suggestions.  

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68scott385
I mow my lawn and find Chevys
Posts: 1994
Joined: 10/09
Posted: 11/07/12 04:27 PM

I personnally like the AFRs.  
68scott385 68scott385 68scott385

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skyeking
I mow my lawn and find Chevys
Posts: 2738
Joined: 08/09
Posted: 11/07/12 04:56 PM

Hi there,
more than a year ago we decided that crankshafts
don't win as many races than Valve springs do
when perfectly matched to all of it's suitable
componetry..HI PONCHO MAN.....All the best..Noel  
skyeking

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