RobertISaar Posted April 24, 2007 Report Share Posted April 24, 2007 in the vrooooooooooooooom thread started by justin, blackbird21 said that a 2.8 could hit 9000RPM. i think thats way over the top for an OHV motor but i dont know much about 60* motors, so is it possible? if it is what would happen if i took the crank from a 2.8, stuffed it and the longest rods i could find in the block of a 3400 OHV using aluminum heads from a 3100? kind of the same idea of a chevy 302: monster pistons, miniature stroke. i dont know if i understand this right but do longer rods help your engine live at higher revs? Quote Link to comment Share on other sites More sharing options...
Andrew Posted April 24, 2007 Report Share Posted April 24, 2007 its the short stroke of the 2.8 that would allow it to rev higher. the 3.1 has a long stroke with short rods. Quote Link to comment Share on other sites More sharing options...
mfewtrail Posted April 25, 2007 Report Share Posted April 25, 2007 Since it's sorta related...turboz24(Curtis) here revs his 3.1 to 8,000rpms. Here's his engine info. http://turboz24.com/Specs.htm Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 25, 2007 Author Report Share Posted April 25, 2007 i'm no expert here but 8100 is pretty good for a 3.1, right? Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted April 25, 2007 Report Share Posted April 25, 2007 8000 rpm is high for any motor. Especially when you get into the v8's. But for a v6, yes that is pretty high Quote Link to comment Share on other sites More sharing options...
FordBoy Posted April 25, 2007 Report Share Posted April 25, 2007 9000rmps is even high for a 4banger but it can do it pretty easy Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 25, 2007 Author Report Share Posted April 25, 2007 dont suppose anyone has ran these on a dyno? seems like the relatively small bore and valves wouldnt flow enough air to make it worth it. Quote Link to comment Share on other sites More sharing options...
Brian P Posted April 25, 2007 Report Share Posted April 25, 2007 its the short stroke of the 2.8 that would allow it to rev higher. the 3.1 has a long stroke with short rods. actually the rods are the same. It's the pistons that are different. Quote Link to comment Share on other sites More sharing options...
MegaDestroyer Posted April 28, 2007 Report Share Posted April 28, 2007 so what is the redline of a 3.1 then? Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted April 28, 2007 Report Share Posted April 28, 2007 its the short stroke of the 2.8 that would allow it to rev higher. the 3.1 has a long stroke with short rods. actually the rods are the same. It's the pistons that are different. + crank. stock 3.1 redline is like 5500 lol. something around there. Quote Link to comment Share on other sites More sharing options...
1990lumina Posted April 29, 2007 Report Share Posted April 29, 2007 yellow line is 5500, 6k is redline Quote Link to comment Share on other sites More sharing options...
19Cutlass94 Posted April 29, 2007 Report Share Posted April 29, 2007 3.1 and 3100 redline at 6,000RPM. Although both are computer shifted at ~5,400RPM at WOT Quote Link to comment Share on other sites More sharing options...
1990lumina Posted April 30, 2007 Report Share Posted April 30, 2007 And I believe fuel cut off stock is 6200rpm? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 30, 2007 Author Report Share Posted April 30, 2007 i just thought of this: i know this is a problem when dealing small block chevys but i dont know about 60* V6, but are the journals the same sizes on the crank, both of the ends on the rods and the pistons? Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted April 30, 2007 Report Share Posted April 30, 2007 I think the journals are a little narrower on 660*, people have used 350 rods I believe but needed to have the crank end shaved down just a tad. I would also check 60degreev6.com, a lot more guys do performance builds over there than here. They know their stuff. Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted April 30, 2007 Report Share Posted April 30, 2007 or did you mean between a 2.8 and a 3.1? I think swapping the crank is all you'd really need to do, then pistons if you wanted. the rods should interchange. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 30, 2007 Author Report Share Posted April 30, 2007 or did you mean between a 2.8 and a 3.1? I think swapping the crank is all you'd really need to do, then pistons if you wanted. the rods should interchange. basiclly 3400 block and pistons, 2.8 crank and the longest rods i can fit and not smash valves do all 60* V6s have forged crank and rods or is it just the 3100? Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted April 30, 2007 Report Share Posted April 30, 2007 all have forged rods, I'm not sure about the crank. Quote Link to comment Share on other sites More sharing options...
White93z34 Posted April 30, 2007 Report Share Posted April 30, 2007 why would you put a crank that is effectively destrokeing the engine in? you would go from like 3.4L to what 3.2? 3.3? so it can rev higher? lets say you built a valvetrain to support 9000rpm, what are that odds that you would actually make any power up that high? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 30, 2007 Author Report Share Posted April 30, 2007 as long as i could get the intake, heads and exhaust to flow enough air, why not? i've seen kawasaki ninja 250s turn 14,000 RPM. yeah i know its only 250cc. still, a prepped 302 stands up to 8000RPM and it makes power all the way to its redline. hell, the LS7 has a redline of 7,000 but in testing it stood up to 8,000 with no problem but i didnt make any more power after, i think, 6,300. which means as long as i can open up a manifold far enough, port the heads enough, get the valves wide enough, fabricate some decent headers, get a long enough duration cam, use solid rollers, and have the ability to computer tune, i'm gold. that and if i did it with a larger displacement motor it would be even harder to flow enough air to turn 9000. id have to eventually dyno it to tell how well i would be doing. Quote Link to comment Share on other sites More sharing options...
digitaloutsider Posted April 30, 2007 Report Share Posted April 30, 2007 why not? I think the real question is "why?!" What is it with this 2.8 bullshit all of a sudden? There's a reason why GM dropped it. It would take THOUSANDS of dollars to do all the work you want to. If someone put that same amount of money into say, an L67, you wouldn't have a snowball's chance in hell. WHY bother with this motor? It's old, it's gutless and that's all it'll ever be natually aspirated. Let it die. [me=Captain Danger Awesome]puts on flame suit.[/me] Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 30, 2007 Author Report Share Posted April 30, 2007 who said anything about naturally aspirated??? a turbo for each manifold. that and its something different. do you know anyone else whos done this? and yeah i know, its a money pit. if i wanted something cheap and somewhat fast i'd get a carbed 350 from summit for about 2,300 complete and stuff it in a $200 car. i'm working with what i've got without turning to foreign cars to make a sleeper. Quote Link to comment Share on other sites More sharing options...
digitaloutsider Posted April 30, 2007 Report Share Posted April 30, 2007 Regal's are plenty good sleepers. Shit, GTP's don't get second glances from most people. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 30, 2007 Author Report Share Posted April 30, 2007 with this being a 60* motor i could stuff it into anything i wanted without having to worry about clearence, unlike any other performance motor... minus the LQ1... dont know about the 3.5 Quote Link to comment Share on other sites More sharing options...
White93z34 Posted April 30, 2007 Report Share Posted April 30, 2007 i mean lets say you went as far to get huge injectors, spent so much on 2 turbos, had some heavy duty valvetrain, and somehow got a set of intakes and heads that could all support it, you might be able to rev to 9k, but that would be the end of it. i don't get the obsession of being able to say "i can rev to 9,000" how about making power? a 2.8 is gutless, there is a reason it was dropped in favor of the 3.1. just buy a 3400, get a decent set of injectors, and a decent tune to start with, and you will be light years ahead of a 2.8. and should put you well under $2300 Quote Link to comment Share on other sites More sharing options...
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