AMV8(1day) Posted November 9, 2006 Share Posted November 9, 2006 Anyone and everyone that has gotten the Chevy High-performance Dec. issue should check out the Performance Q&A on pg16 titled Mighty Mouse. For those in the dark the artical is about a supercharged sbc chevy measuring in at 302c.i. putting out 600 horses on 91 pump gas and running a 25mpg average during the entire Hot Rod Power Tour (driven the whole time in a 65 chevelle with a richmond 6-speed and 3.55:1 rear end gears). How light and far back in the engine bay do you think someone could get a chevy sbc302c.i. with a Lengenfelter/ACCEL Super Ram induction box or better yet; a TPIS mini Ram fuel injection kit, with a Vortech supercharger slapped on? Jeff Smith, the guy that cooked up the idea and built a realiable, small cube, big power, great milage engine, is also talking about a supercharger upgrade to a Magnuson High-Helix 122-cid Eaton blower spitting out as much as 675 to 700 hp at 6500RPM with similar mpg numbers. I'll get the full artical on when I get a chance. Quote Link to comment Share on other sites More sharing options...
AMV8(1day) Posted November 9, 2006 Author Share Posted November 9, 2006 Oh, and provided one went with all lightweight components (aluminium heads etc.) what would such a setup weigh in at? what kind of weight dist. would you be looking at in a '77 280Z? Quote Link to comment Share on other sites More sharing options...
specialk Posted November 9, 2006 Share Posted November 9, 2006 chevy 283 - 400 ci engine are all the same external dimensions, so mounting won't be any different. As far as weight goes, I don't think there's much difference either (but of course I could be wrong) Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted November 9, 2006 Share Posted November 9, 2006 I'm no expert here but I'll ante up my 2 cents anyway. The 260, 283, 302, and 350 are all the same block and can be bored/stroked to over 400 CID. SBC 400's weigh about the same, are the same physical size and mounting scheme as the 260-350, and can be bored/stroked all the way to 454. I think I read somehwere that the 400 can be go up to 472?? In theory, a 454 stroker (or 620 BBC for that matter) should get about the same MPG as the little 260 SBC with all other factors equal... again, in theory. The math tells us that, since a motor is just an air pump, it will only use the air/fuel needed to provide a given HP demand. If we only use 50 BHP from the engine, it only uses that much fuel be it a 260 or a 620 CID engine. The 620 just has more "potential". Real-world figures seem to always differ from theoretical math though. Maybe this is due to internal resistence and rotational weight differentials of engine components?? I don't know but, from what I've read, a 600 BHP 620 BBC can achieve nearly the same MPG as a 302 SBC with 300 BHP. Again, I'm no expert on this but, as with any motor, MPG efficiency is all in design, component matching, tuning, and keeping ones foot off the gas under normal driving conditions. I'm replacing my 350 SBC with a 434 or 454 stroker soon for the bigger numbers possible. I'm not using any forced induction but will hit it with 200 HP of N2O from time-to-time. I expect my MPG to INCREASE due to more attention given to the factors in the paragraph above. Quote Link to comment Share on other sites More sharing options...
rytherwr Posted November 9, 2006 Share Posted November 9, 2006 Mike, I don't believe you can take a standard SBC block safely out any further than 4.125. All of the bigger SBC I know about use aftermarket blocks specifically made for either larger bore, taller deck or both. I have a Bill Mitchell 454 special edition in my Z and it is built on an aftermarket block from World Products. Wayne Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted November 9, 2006 Share Posted November 9, 2006 Yeah... I guess I'm mixing apples/oranges regarding "how much" a 350 and 400 block can be bored/stroked. I realize good aftermarket blocks are better-suited to big cube mods. Sorry for the confusion. I only brought this up to clarify my point about engines being air pumps. The basic premise remains, which is that fuel economy is primarily affected by spent energy rather than CID. So it's not as advantageous to fuel econonomy as some might think to build a really hot 600 BHP 302 vs a milder-built 600 BHP 454... and the milder build is easier... and it's more streetable. EXPERTS and PROS.... please correct me if I'm wrong but this is what I understand as truth from reading these forums. Quote Link to comment Share on other sites More sharing options...
AMV8(1day) Posted November 9, 2006 Author Share Posted November 9, 2006 Well I don't claim to be an expert in fuel economy, but my old ford 302 was lucky to get 12mpg on the highway and I wasn't pushing out anywhere near 600 horses. And his combo seems to be much more streetable than mine ever was considering he drive the entire Power tour without any issues and still has the car today as a shop car. I just thought it was pretty cool and a feat of ingenuity to pull off a streetable 600hp sbc with better fuel milage than your average japanese compact. Quote Link to comment Share on other sites More sharing options...
Twoeightnine Posted November 9, 2006 Share Posted November 9, 2006 I'm no expert here but I'll ante up my 2 cents anyway. The 260, 283, 302, and 350 are all the same block and can be bored/stroked to over 400 CID. Mike..whats up mister? Did I miss something or are you apple and orangeing your engine sizes. 283 is Chevy. 302 is Ford. And shame on you....you for got the 289! Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted November 9, 2006 Share Posted November 9, 2006 Chevy made a 302. Isn't it the same block as the others:confused: If not, then indeed I am ashamed:redface: The 289 is definitely Ford:wink: Quote Link to comment Share on other sites More sharing options...
Twoeightnine Posted November 9, 2006 Share Posted November 9, 2006 Ah .......you said Ford. I wasn't born near the beginning of the century so I cant speak for the blocks that I have not handled but the last half of the century Chevy used a 305 which is basicly the same dimension as the 350 block with smaller cylinders. One would not want to waste ones time building on a 305 when one would have a grand ol time stroking a 350 instead. Edit: Better yet why exclude the twister. The 327. The Z would love that motor! (Jess dump a tree fitty in er an get er done) Quote Link to comment Share on other sites More sharing options...
Paz8 Posted November 9, 2006 Share Posted November 9, 2006 You can build almost any engine to do whatever you want, the bottom line US Dollars. Light weight high power engines to pull cars along cost real money, something us regular guys actually need to work for. My 2 cents worth. Quote Link to comment Share on other sites More sharing options...
boodlefoof Posted November 9, 2006 Share Posted November 9, 2006 Wow, they're re-running that article? I remember first seeing that article about 6 years ago in a special edition of CHP entitled "Engines" or something of that sort. Nice little engine though! Quote Link to comment Share on other sites More sharing options...
Z-8 Posted November 11, 2006 Share Posted November 11, 2006 They wern't re-running the article, someone had sent in a letter(or e-mail) asking about a small block making big horsepower, and great MPG. They printed the main details from an e-mail sent from the guy who built the engine. And then they mentioned something about making more horsepower with it in a future article. Quote Link to comment Share on other sites More sharing options...
AMV8(1day) Posted November 15, 2006 Author Share Posted November 15, 2006 So no one actually answered my question, what kind of weight would I be looking at with a force fed SBC set as far back as possible in a 280? Quote Link to comment Share on other sites More sharing options...
Mike kZ Posted November 15, 2006 Share Posted November 15, 2006 Chevy made a 302. Isn't it the same block as the others:confused: If not, then indeed I am ashamed:redface: The 289 is definitely Ford:wink: A Chevy 302 is an early 327 with a 283 crank. Quote Link to comment Share on other sites More sharing options...
Mike kZ Posted November 15, 2006 Share Posted November 15, 2006 So no one actually answered my question, what kind of weight would I be looking at with a force fed SBC set as far back as possible in a 280? Depends how much you beef up the frame, how much roll bar, etc.. Somewhere between 2400 - 2800 lbs Quote Link to comment Share on other sites More sharing options...
AMV8(1day) Posted November 20, 2006 Author Share Posted November 20, 2006 bump Quote Link to comment Share on other sites More sharing options...
HarrisonTX Posted November 21, 2006 Share Posted November 21, 2006 I cant really help you with your question, but im building a 302 for my 260z also! good luck Mike KZ, thats not how chevy built theres from the factory, the way your talking about, the 283 crank, into a 327 block will only work if both are small journals. Thats how im making mine, and it actaully comes out to a 301, not a 302. Chevys 302's were actaully Large crank journals. Quote Link to comment Share on other sites More sharing options...
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