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i just got my 250 with a .060 overbore back today. i went with the sbc valves with a four angle valve job. i was just wondering about the cam i was thinking about clifford's 270H cam. has anybody used this in a setup like mine. this is going to be a regular street driver with a 4bbl and tube headers.
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That should work pretty good for you.But if you are going to run a AT I would step up the stall speed Other wise it will be just fine with a 4-5 speed. }[oooooo]
------------------ NovaMan/Twisted6/Larry
Larry/Twisted6 [oooooo] Adding CFM adds boost God doesn't like ugly.
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yeah i plan on running a 5 speed has anybody ever dynoed an engine like this. what kind of power am i looking at.
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You should have somewhere between 200-250hp ball park(ruff guessing here) this assumeing that you have somewhere around 10-1 compression seeing that most 250s only had about 110-155hp stock out of the box an only about 8-1 compression you don't start getting The 1 hp per cube till you get up over that 11-1 12-1 compression area some say 11-1 and up I have always known or figured it as 12-1 to get the 1 hp per cube. But even at 10-1 I would be running some better gas not the cheap stuff(87) it may want to ping alittle? hope this helps }[oooooo]
------------------ NovaMan/Twisted6/Larry
Larry/Twisted6 [oooooo] Adding CFM adds boost God doesn't like ugly.
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the compression has probably not increased that much i tried to keep it low in hopes of running either a turbo or nitrous. i am really intertested in the turbo but since i am only running cast pistons i am kind of worried. i would keep the boost low but i do not know if that alone will be enough. i have even thought about water injection to help control things better but i have never done anything like this. the people at holley said that a 75hp shot of nitrous is all it would take. that would get me right up close to the 300 mark. i was guessing about 220hp so i was in the right ballpark. if i could find a diagram on how to route the turbo plumbing i would like to go that way if you thiunk the engine can take it.
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The stock pistions could work But Question is for how long I wouldn't push the boost over 6psi. But you will also Have to rethink your cam? The turbo is like a blower The cam has to be for that reason.High duration cams are not good. As for the plumming each is different ,you can use the stock exhaust man. header of some kind. I have seen many different settups.What is your ride anyway.? again how much room do you have to work with also plays a big part in plumming a turbo. Now as for the Baby bottle .Well my2cents If you need it then you didn't built it right the first time or couldn't afford to .To me thats just a pour mans hp.
And to me it's to easy to waste good money and hav eit blow up because of a air bubble and it leaned out or a selianod got stuck. so I'd stick with the turbo or a blower. I plan on a turbo motor later down the road myself on top of my intake and carbs with a cooler. to cool the air intake. So if your asking me about the NOS sorry i'm the wrong guy to ask. I know the NOS works and how it works and almost went there once but again just my 2cents To me just to easy to waste good time & money. I built the motor i have been running Now since 86 and have Never been into it .Yet for any reason. So i believe I built it right you don't see to many race motors last this long with or wiht out turbos, blowers Or the NSO. guess you mite say maybe I have been lucky or what ever.But I'm happy the way it is even if i have gone from 1 carb to 3 now lol Hope this helps and sorry for the long Note. }[oooooo] PS. maybe my next motor will last as long ------------------ NovaMan/Twisted6/Larry
[This message has been edited by Twisted6 (edited 03-08-2002).]
Larry/Twisted6 [oooooo] Adding CFM adds boost God doesn't like ugly.
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one would think that the cast pistons would absorb a lot more heat causing less power, more chance for detonation, and higher operating temperatures. would this even be a problem at 6psi?
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I'm not that much into the turbo stuff just yet But i am getting into that much deeper now that i have one. You have a good point there and maybe right. But the Timeing plays a much bigger part with turbos & blowers then it does in a stock motor. Because of that reason. It is best to have a inner cooler if possable. not just because it will net. more power from the unit But to help in the heat side of things also. A turbo can put out more power then ANY motor could ever handle. That is the BIGGEST & MAIN reason For Waste GATES. Hope this helps. }[oooooo]
------------------ NovaMan/Twisted6/Larry
Larry/Twisted6 [oooooo] Adding CFM adds boost God doesn't like ugly.
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your deffinetly right about the inner cooler. if done right you shouldn't need more than 8 psi on a street engine. I remember hearing about lingenfelter using nos in a land speed car. He turboed a 350 and used the nos to cool the inner cooler and this was all done on 6psi boost. I'm not sure how it was set up but it seems pretty clever. with intake air that cold and dense the thing should have throttle response like a n/a motor
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