79 impala getting a 03 vortec

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my1979impala

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Alright guys so here is the deal. I have a 79 impala that has been in the family since new. It was my first car and I love it. The thing is it finally had a heart attack. Came from the factory with the 305 2 barrel and at 220xxx miles its just worn out.

Now, I have acquired a 5.3 vortec engine to give the car new life. Got a deal on the motor, trans, harness, computer and accessories. My goal is to get the new heart up to around 400 hp before I put it in. I have read and read and read and it seems that every time I think I know something I read something that says otherwise. I was wondering if you all have some concrete info on what I need to do to get to my goal. I want something reliable but im also not looking to spend tons of money. Im all for doing a cam swap or whatever. The car is going to be a daily driver but im also going to be doing some racing with it.

What I have is a stock 5.3 vortec out of a 03 taho. 862 heads and the tall truck intake manifold. has the mechanical fan.

What im looking for is part numbers or direct links to web sites. Also it seems that most of the things ive read are for truck applications. Since im putting this in a car i would think that some things would be different. Ie more hp verses more torque. any advice or tips would be appreciated. Also im definitely going to be putting on some long tube headers. Do you all have any suggestions on which ones to go with?
 
go to a site such as www.summitracing.com enter the engine make and type and size, chevy, GenIV, 5.3. You will come up with tons of stuff for the engine without regard to what type of vehicle. Select for instance a camshaft and decide whether you want to go street or street/strip. They have all sorts of filters to narrow down all the possibilities.
 
got a few minutes to cruise summit but didnt find much. I think i just need more time to look though. Quick question though. Everywhere i look it seems that they are giving specifics about cam shafts but no real hp/torque gain numbers. Is there somewhere i should look to see what duration and lift numbers i need? or is it more of a get one and see what happens thing? also Im still looking at headers. Ive read many bad reviews about pace setter headers so im kinda falling away from them but the only other ones summit sells are kooks but they seem to start at the $1000 range. can anyone recommend a good set of headers for a decent price? also is there enough of an advantage to go with stainless or ceramic headers over painted ones?
 
Nobody can give you specific gains for a camshaft because there are too many variables, head flow, intake design, carburetor, just too name a few. You also have to take into consideration the transmission and rear end gears. As an example you can't install a cam that produces power in the upper rpm range if the rear has gears that are numerically too low and the torque converter has too low a stall speed. Competition Cams has a piece of downloadable software on their site where you can put in all the variables and they come up with recommended camshafts.
The problem with painted headers is they require constant maintenance, the paint chips and then rust forms. I also can't seem to find headers for an engine swap into an Impala. The link you provided for JBA is not for your car.
 
Ill have to get some time to check out the comp cams site and see what they recommend. I built and am very familiar with jeeps and gearing in the axles. I understand the need for changing gears. I do not know anything about torque converters or why i would need to change that (all jeeps i worked on were/are straight drive) but everywhere i read they suggest changing it once these setups gets to the 400 hp range. can you explain that? and yeah i started looking more for headers that were made for the motor rather then for the vehicle. it seems that there are not many, if any, out there for swapping a 5.3 into an impala. Do you know if Ls1 headers would fit onto the 5.3? im sure they make those to fit in the impala.
 
To get 400 horsepower out of a 5.3L engine requires a cam that may not generate sufficient vacuum/torque at idle to permit the car to be placed in drive with a low stall speed torque converter and still move off the line with decent performance. The link below gives more detail. The LS1 header may fit the engine but I see none for the Impala body.
http://www.badasscars.com/index.cfm/page/ptype=product/product_id=78/prd78.htm
 
That was a good read for the torque converter. thank you for that. and yeah i cant find anything stating that it will fit the impala body but im trying to come up with something close. My thought is that full length headers for a tahoe are going to somewhat follow the lines of the stock manifolds. as in they would not make the headers wrap down to where they would interfere with the motor mounts. Along with that the stock manifolds are similar in size to the ones on the original motor so my thinking is that if i were to get headers for a tahoe they would possibly be close enough to fit in the impala. I can notch the frame and do some modifications like that if needed, dont really want too but i can. My only other thought is to find some ls1 heads to fit something similar in size and shape as the impala. maybe a chevelle or Monte carlo
 
ok so in my searching i found this.

http://ls1tech.com/forums/conversions-hybrids/1202635-b-body-conversion-gm-full-size-77-96-a.html

According to deuce on there it seems that i can use f body long tube headers as long as i put the new engine where the old one sat. so this means i should be able to use headers for something like an lt1 or ls1 camaro right?

Also, Im looking at keeping the old gas tank and deleting the evap system from the engine since i wont have a pressure sensor in the tank to make it work. what should be done with the pressure relief line? can it be run straight into the manifold (bypass the purge solenoid?) or should i do something else with it?
 
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You can't run the evap line to the intake it will be constantly applying vacuum to the gas tank. I would leave the line open and put a metal gas filter on the end to prevent anything from entering the line yet still vent the gas tank.
 
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