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ive got a 327 small journal id like to run a 283 crank so i can get it to rev. (i dont want much tq but instead hp and it to rev. (its going in a very light nissan)

id like to know the longest rods i can run and will this determine the pistons i use? id like 400 whp to a t5 and a r200 nissan diff.
 

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blight said:
ive got a 327 small journal id like to run a 283 crank so i can get it to rev. (i dont want much tq but instead hp and it to rev. (its going in a very light nissan)

id like to know the longest rods i can run and will this determine the pistons i use? id like 400 whp to a t5 and a r200 nissan diff.
A 302 by any other name. You will have to engineer your components around the finish machining of the block. An example is the combination of the 1/2 the stroke, plus the rod length, plus the distance from the middle of the piston's pin hole to its crown cannot exceed the distance from the center line of the crank to the head deck. For a stock block that's 9.025 inch, for a post machined block it may be less if the head deck was milled and/or the mains align bored.

Bogie
 

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Take a 9" deck height, subtract 1.5" (half the stroke)- that leaves you 7.5" to play with- 6.25" rod and a 1.25" piston height is a pretty easily found combo. You can also run a 6" rod and a 1.5" piston- which are REALLY easily found parts. Of course you'll need to play with final piston height, deck height, and gasket thickness to get it al finely tuned.

You're also going to need some good heads- aftermarket units with a 50cc chamber would be a great starting point, for a street engine I would go with a 190-210 intake runner depending on how agressive of a valvetrain you plan on running and how high you want to spin it.
 

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Use 327 connecting rods and 302 30 over, you will get 315cid. Get a nice healthy cam & heads, and a good intake and 750cfm carb you will get 400 horse, no problem.
 

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FEDDO said:
I have been looking for a way to increase the cu in in my 301-283 bored to 4'', changing rod length and additional,.030 bore and I have found 14 more cubes, can't beat it. :rolleyes:

I wouldn't take a 283 to 4.030" adn connecting rods have nothign to do with displacement, why 327 rods were mentioned I don't know...
 

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283 Rods are weak. They will break. A friend I know had a 283 in a street rod. One day the 283 was making banging noise and it turn out one rod split in two, and 327 rod is the same length and much more beefier.
 

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That can eb rue, but I think he's looking for aftermarket rods since eh asked for the longest ones he could use. 5.7" rods are very common and stock rods are given away all the time, but I think he wants something a little better. 5.7" rods are an option though.
 

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FEDDO said:
I have been looking for a way to increase the cu in in my 301-283 bored to 4'', changing rod length and additional,.030 bore and I have found 14 more cubes, can't beat it. :rolleyes:
LOLOL

Doncha just gotta love some of the "stuff" that gets spewed!!

I swear if it wasn't for crap like this, I would enjoy the forum a lot less, though. Nothing like comic relief, ya know? :D

Biggest problem w/some early rods are the small bolts.
 

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DoubleVision said:
I wouldn`t destroke the 327 just for revs, as it will rev just as well.
Your looking at some cash spent if you go the way you plan to go, longer rods and custom pistons aren`t cheap.
I agree with you, but the guy already has a 283 crank.
 

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use evething 327 and just put a 283 crank in and check your clearences, that was how GM made the 302!!! I was nothing to see that motor run 9000 rpm back in the day, But I do recomend replacing the stock bolts, use ARP steel rod bolts and main bolts or studs and have the crank turned if needed and rods trued.. it will be much smoother!!!
 

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Although I wouldn't trade my 327 small journal crank for a 283 small journal crank, hey, whatever floats your boat.

Just playin' around here.....
4.030" 327 block.
3.000" 283 crank.
6.000" rods.
Forged pistons with 0.100" solid dome. What we're looking for here is the smallest dome we can use that will get the crown value to close to zero, neither negative nor positive, so we can make a 10.0:1 static compression ratio motor using 60cc heads. We want to use 1/16th inch or thinner rings to minimize flutter at high rpm's.
L31 Vortec heads, 062 or 906. Cut 0.028" off the heads to arrive at 60cc chambers.
High-rise single plane intake. You wouldn't believe how long it took to find a single plane intake that fits Vortec heads, but here it is....Amazingly, I cannot find a comparable single plane Vortec at Edelbrock or Weiand.... :eek:
Professional Products Hurricane+Plus Vortec, satin part #52033, polished part #52032
750cfm carb of your choice.
10.0:1 static compression ratio.
1 5/8", long-tube, equal-length headers. I ran this DynoSim through open headers, because this sounds like a race application rather than a street application. Through the mufflers takes away 30 hp on the DynoSim.
http://www.compcams.com/Cam_Specs/CamDetails.aspx?csid=236&sb=0
RPM HP TQ
3000 185 323
3500 240 361
4000 301 395
4500 360 421
5000 410 431
5500 449 429
6000 479 419
6500 499 403
7000 506 379
7500 506 355
8000 489 321
Volumetric efficiency 101.8% @5500
BMEP 212.2 @5000
This motor makes a beautiful wide and flat horsepower curve on the DynoSim graph. I wish I could find a way to show you, but can't figure out how.

I've run DynoSims on these small motors before with Vortec heads. They really seem to like 'em. This is using the published figures for flow. If you were to do a little bowl work, there might be more to be had.

On another thread, F-BIRD'88 suggested that the information given by David Vizard on his site concerning head flow and how to improve it should be required reading by all us knotheads. I agree.
 

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the PP intake is modeled off of the Victor I believe, but it may be a Suber Victor, Edelbrock does make it for the Vortec.

I would NOT run Vortec heads though. With all of the other moeny you're looking at dumping into this the extra few hundered dollars for some RHS 200cc heads with 50cc chambers- its an all around better head and eliminates the need for a dome- a win win situation, plus you can run any standard style intake manifold- again a win.

Vortec engines are GREAT for a shoestring hop up build but if starting from scratch there are others that can do just as well or better for only a slight amount more.

And if you're only wanting 7500 RPM's I'd just run a 327 with a 6" rod and a off the shelf 2 eyebrow flat top light weight forged piston. A KB790 would do pretty well in this application.

I'd be curious to see what DD says about this combination compared to the VOrtec, of course I don't think it takes the drawbacks of a dome into account, nor rod length. But it'd be neat to see what it estimates for a ballpark difference between the two with a longer stroke and better heads.
 

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techinspector1 said:
If you're spending YOUR money, you can use anything you want to. I'm spending HIS money, so used cheap heads and cheap flat tappet cam.

Used vortecs are not so cheap by the time you're done- you need to swap to threaded rocker studs and guide plates, change the guides and spring pockets, probably true the surfaces, and God forbid you want to step up to a larger valve combo and do the bowl/port work to accomodate that- even if you get them used you're looking at atleast a $500 proposition, toss into that harder to find intakes and pistons and all of a sudden the price difference isn't as great as you'd think.

I made the mistake of trying to hop up a used set of Vortecs, they are good for a very mild cam, springs, intake, carb, piston, and exhaust hop up engine and with just those mods can make over 400hp, but If you're looking for real power, something that will have resale value, and a bargin, aftermarket cast iron heads are a real valid option. They're also built MUCH tougher to boot!

You're option uses used heads with matching machine work, a new intake, and harder to find pistons- mine could use a $50 used intake, new heads, and a easy to find piston. You're is honestly a little cheaper, probably around $100, and it also will make less power and sell for a few hundered less should he ever decide to get rid of it.

Both options are valid choices, yours would require slightly less initial investment, mine would make more power and retain more value over time. Its a decesion that the builder has to make.

I DO AGREE with the cheap flat tappet cam though, this one is simmilar to the one you suggested but is a little more "top heavy"

http://www.competitionproducts.com/prodinfo.asp?number=1090M

It's cost for the cam and lifters is $115, you can get direct lube lifters for another $55. I'm actaully planning to use this kit on a 350 of my own in the future.

TI, you're a real nice guy and in no way am I saying what you have said or done is incorrect- you really go the extra miile to help these guys and occasionally myself- I just feel that Vortecs have their place and it is limited, they are not the "one size fits all" head.
 

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67-4-fun said:
use evething 327 and just put a 283 crank in and check your clearences, that was how GM made the 302!!!
I'm not gonna try to embarrass you. Just please double check yourself before posting- I'm speaking from experience, having said basically the same (incorrect) thing you just did, in a moment of distraction.

(Hint- pin height)
 

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cobalt327 said:
I'm not gonna try to embarrass you. Just please double check yourself before posting- I'm speaking from experience, having said basically the same (incorrect) thing you just did, in a moment of distraction.

(Hint- pin height)
LOL got ya...I was just sure of myself, I have always been told this by several guy's that the 302 was created by using 327 rods and pistons and block but used a 283 crank, but guess i was wrong. i had the option to do this to my 327 but did not, So is { pin height} the only change they did to make the 302 or is there other machine work that was done that Im not aware of??
 
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