|01-11-2013 11:39 AM|
Edelbrock C427x manifold
|01-11-2013 12:34 AM|
|MalibuMike||Lol ya'll funny, welp I'm glad I got the info I needed before yu guys jumped ship on me...|
|01-10-2013 11:39 PM|
|01-10-2013 08:20 PM|
|cobalt327||I have nothing more to add except good luck.|
|01-10-2013 08:15 PM|
|vinniekq2||now you want a 700 horse power engine? You will just blow the tires off the car and hate driving it on the street|
|01-10-2013 07:13 PM|
|MalibuMike||Okay well right now I'm looking @ a set of NEW ROSS RACING PISTONS ALUMINUM FULL FLOATING. CNC. MACHINED. SKIRTS .060 454 OPEN CHAMBER PISTONS PART #80001 (Yes I still wanna go with the .060 bore just to have alil edge in a sibling rivalry; my 2dr '80 Malibu vs my brothers 4dr '82 Regal w/455 Buick motor) Would these pistons be a good fit with my heads?|
|01-10-2013 02:48 PM|
Rectangle port heads are for high rpm use. The crossover point where the rectangle ports pulls ahead of the oval port heads at a higher rpm and lift than you'll be needing, so the rectangles are not for you.
You might want to consider adding 2.19" x 1.88" valves if you have the budget- but for a torque engine this isn't mandatory. Be sure to pay attention to the valve spring installed height so there's enough spring pressure and clearance. If you do get bigger valves, you should look at using 0.100" longer valves to have plenty of room for setting the installed spring height.
781 heads are right about 122cc chamber size. That means you'll need a domed piston to have any sort of compression. Flat tops will have you at or below 8:1.
More: 781 vs. rectangle port BBC heads.
|01-10-2013 02:25 PM|
|MalibuMike||Okay I'm getting a lil better understanding how it (bore sizes) work, but I was "TOLD" the largest a 454 could be bored is .060... Neways, how do I build the motor for torque? Keep in mind guys, like I stated in an earlier post "this is my first time dealing with a big block" so be patient with me. As of now my motor has 336781 heads, would I be better off using these or swapping them out for a set of rectangle port heads?|
|01-10-2013 12:08 PM|
|01-10-2013 12:04 PM|
Looking at it from a power standpoint, the extra size is worth about 1 hp and 1 ft/lb torque per ci. So the difference between 0.030" and 0.060" is about 6.5 hp and the same amount of torque, all else being equal.
|01-10-2013 11:47 AM|
Yes, the horsepower diffrence is small. Just don't do like a customer of mine just did and bored a 454 good std. bore block +.125 on the first build. Wanted "cheap" cubic in. (Cuatomer is ALWAYS right?)
Actually with a .030 bore you have a lot of choices for further builds. +.040 .060 .070 .080 .100 .125 .130 are common sizes for these blocks..
As mentioned, for street use, build for torque and drivability.
|01-10-2013 09:53 AM|
|MalibuMike||I wanted to go with the .060 bore because to my understanding the bigger the bore the more power & the faster the car or hav I been misled?|
|01-10-2013 01:35 AM|
Edelbrock C427x manifold
Why are you stuck on the .060 bore? When taking a block in to the machine shop usually you would bore the block to what it takes to clean up the cylinder walls. Sometimes boring to larger bores can cause problems such as overheating. I not saying it will happen on your 454 the walls are pretty thick. There is 7 cubic inch difference between a .030 block and a .060 block. Bore it as you like and use Probe forged piston P2465F-060. Take a look at post #12 the parts I listed are the almost same as Vinnie built his engine. The specs on the Comp cam Xe274H is .552/.555 lift 230/236 duration. You will need a good 3000 rpm stall like Hughes HUP-GM30. 400 hp and 510 lbs torque is considered a mild oval port engine. Have the block zero decked. Work on the heads by installing 2.19 intake valves and 1.88 exhaust valves. With this setup your static compression will be 9.687 and the DCR will be 8.269 excellent for pump gas.
|01-10-2013 01:27 AM|
You need to start by seeing what pistons are in it now, and go from there. If they're sufficient for compression (and the engine is sound- good bearing and piston to wall clearances, etc.), then basically all you need is a cam and lifters, dual plane high rise intake like the RPM, 750 cfm carb, long tube headers/dual exhaust system and a recurved HEI distributor to have plenty of power for any street driven car.
I wouldn't worry too much about HP numbers- it's hard to NOT make 400 HP-plus! Build it using the correct cam for the compression ratio and as long as you choose and assemble the parts carefully, you could have ~500 HP in a streetable package. But the street manners wouldn't be as good as a torquier combo, IMHO. I depends on how you're going to use it as much as anything. A daily driver usually needs to be milder than a weekend toy.
Even using a cam as mild as the XE268H and those heads along w/using an 18cc domed piston (about 9.6:1 CR) will get you an easy 450-plus HP/550 ft/lb torque. BTW, if you have flat top pistons, the CR will be about 8.1:1 using the 118cc heads and a quench of 0.041".
I take it the rear end has been changed? Because it came w/a low performance 7.5" diff from the factory, and if that same rear end was in it now, it wouldn't last long behind a BBC if you ever got traction.
|01-10-2013 12:16 AM|
|vinniekq2||bore the engine w/e the machinist says|
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