Jcushing

you guys can talk about some mythical ------- number that is "the best" for every engine out there and cite "side loading" as the only ------- reason why but it jsut makes you look ignorant

you think the only thing going on in a engine is ------- sideloading? how avout valve seat wear from increased RPM's in the cyl head? you think the head/valvetrain cares about ------- sideloading? what about accesories like the alternator and distrubutor? how about the oil pump, transmission clutch and flywheel? saying a low RS ratio motor will ------- fall apart just becuase of sideloading is stupid and narrow minded.

the only thing i agree with that larry said is RPM = ruin peoples motors

you want to talk practical application on one specifit series of motors and not some magic ------- ratio for every engine in exsistance then here we go ON A B SERIES USING STOCK CRANKS AND DECK HEGIHTS the only 2 strokes you want to ---- iwth is 87 and 89. the 89mm will make more power everytime below 9-9500 rpms because 2 reasons, increased leverage on the crank and the rod will pull away from the head on intake and push up on the exhaust stroke faster wich will increase port velocity. the piston wont satrt outrunning the port on a b series untill 9000-9500+. if you want to make stupid high peak power numbers (wich your not going to on stock bore) then rev the ---- out of it and use the 87mm stroke but be prepared for MORE wear on your engine becuase your reving it higher.

it all comes down to were you want to make your power. thats it.... ---- sideloading

xstreetfiendx

i agree with your point, sideloading is one of many factors when building an engine for high rpm operation. also is the engine to run at sustained high rpm? or does it only see high rpm when you perform a ricer fly by to that big block camaro that just whipped your ***. reciprocating weight is a huge problem, as rpm increases so does the centrifugal force on the parts that spin round and round, that's why high tensile strength rods and rod bolts come into play, as well as lightweight valves (Type R) and such. if you plan on spinning your motor at high rpm think of valve springs, if you use stock springs even from a Type R you'll be doing valve adjustments once a week if you run high rpm all the time. Forged rods will stretch, cast pieces won't, that's why they break. this is an argument that could continue into the next millenium, each person has their own opinion about how to build a motor, we all learn from mistakes, if you blow it up, ---- better not use that method anymore.

Tom-Guy

If your engine builder/machinist/mentor is telling you to internally balance a V8, I advise you to promptly forget everything they have ever said and go elsewhere for knowledge. External bob weights on the flywheel are a thousand times superior to internally balanced crankshafts; they counteract dynamic crank flex so the crank does not overflex and wear mains/break/etc. This is one of the tricks Lingerfelter used on his stock cast crank non-4 bolt main 350 engines, that weren't capable of 2000 whp like randumb-kike has pointed out, but still made better power than than most anything with traction you will run across on the street. Yes, 2000whp cars do not have traction on the street - amazing concept, I know!



Yup. Internals that weight absolutely nothing compared to big V8 fare is the #1 reason why sideloading is irrelevant for Honduhs and most small displacement engines. The piston and rod weigh nothing - what loading?

Poor I4 balance, and the inability to externally counterweight one due to design, leads us di-rectally to:


Under big power or detonation/harmonics you get excessive crank flex - flex that exceeds block flex - and the end of the crankshaft bows up enough to run the oil pump gears against their housing. I love loss of oil pressure at torque peak, don't you?

Look at the utter failure of Dart blocks, designed for strong webbings, in high hp applications. Dart's marketing blurb was to the effect that a Honduh engine's main webbings were meant to flex a little in the first place, and what strength they have was weakened by the aftermarket sleeving process. Yet the big power guys not only run sleeved blocks, but they also stopped running block girdles; the crank pretzels up, and the block needs to follow it. Think about that one for a minute. It's classic V8 mentality running up against real world applied engineering - as stated before, most of the tips and tricks and things espoused here are Honduh-specific or one-engine-design-specific, and as soon as you touch something else brace yourself because it might be radically different.

Agreed. It's common knowledge that RS and side loading for A/B/D/F/H Honduh engines doesn't matter. For other engines things are different.


Which is why engines should be freshly built and never started - better yet leave them wrapped in plastic on a pallet and never started because as soon as they see the first rpm the wear process has begun. This is one of the many reasons Widmer is to be disregarded, and that statement to be eradicated from your mind. There are 1001 things you can do to build a reliable big power engine, down to dropping $1.9 million on the build, but in the end the winner is the guy who:

- Spent a minute beating on his ride entirely too hard, doing everything you aren't supposed to, to expose weaknesses
- Turned the boost up so high they weren't sure if the engine would last one pass
- Over spun the engine for practical reasons - ie, more usable powerband, keep large turbo spooled up with shitty notchy gearbox that doesn't want to shift, car is geared so that it needs to be shifted right before the traps which slows it down so you just hold into her and hope it doesn't fall apart, etc.


For NA, that sounds about right. Given enough airmass and there is power past 9500 rpm with LS cranks.




I've yet to see a serious big block that didn't overheat in traffic. At best, you'll find a big block that runs mid to low 7's in the 1/8th on the street. Also, your Honduh lore is to be discounted.

Jcushing

i drive my car to work and i reply on it so that was the basis for the rpm acronym. if going fast is your only concern then you are right, if you ARENT breaking parts then you ARENT going fast engouh. at that point though your car has a life expectancy of 1 pass/lap and anything more than that is a bonus. most people arent there though, infact id say 99.9% arent. most people live somewere between that point and stock so IMHO the point is still valid.

and with boost its obviously a different animal, making power is realive to boost pressure/velocity and duration. with NA you dont have boost to curcumvent velocity

Racintweek

i wasnt talking about actually adding weight, i'm talking about the natural balance and how that makes them more stable than an i4. v8's use actual conter weights instead of balancer shafts that only mask the vibration.

mugenblacky16

This whole topic started out as a question of whether or not a ls crank and rods could be put in a GSR block. I don't know why the topic of RPM's came into play. I never stated anything about wrapping this motor out. I also don't understand why people think the stoke will cause all these problems I'm moving from a 87 to a 89 stoke. Big ------- deal!!! This is a stock LS crank!!! People do ls/vtec engines all the time. If this combo fits then it will work; its that simple. Stay on topic or delete the post and move it to general discussion.

Tom-Guy

Dude, shut the ---- up. We're busy flaming each other, and you can not even post any ****.

Racintweek

first it is quite obvious you are a homo ricer because you have "mugen" in your user name. second if you knew going to an LS cranck wasnt a problem then why ask?? and third some of us are saying stroke WONT cause problems if you arent an idiot.(you might want ot rethink what you are doing :1 )


your question was answered and we moved on to something else, get over it

Slo_crx1

Ok then...slap in your LS crank, it fits. Ditch the oil squirters or they'll get broken right off. Your post right now pretty much validates how little thought people actually put into their builds though. As far as durability goes, it'll be fine for 1/4 mile crap and the typical ricer fly-by's. Most of my experience that I'm drawing upon for my arguments is from track (ab)use...not 1/4 mile track, but as in road course type. The type of racing where for 80% of the time your motor is sitting above the 6500rpm mark.What? So you don't think honda cranks use counterweights either? The counterweights are there, they just don't do as much as one's from v8's. The typical honda counterbalance shaft (mostly in the f-series) was put there more as a luxury than for performance. I see alot of f-series guys that just remove the counterbalance shaft during rebuilds. Fluidampr makes an external harmonic balancer for honda b-series, but I don't see much popularity as far as people running them goes. And here's the reason why right here http://cgi.ebay.com/ebaymotors/B-Ser...spagenameZWDVW. JD's right on the money with his statements with vibration though.