bradkeith

[QUOTE]Originally posted by Marshall89ws6
[and plus 400 is probly the worst goddamn block chevy made....... 350 is good but common...... my favorite motors are the 327 and chevy 302 they both have a 4" bore like the 350 which is neccessary


You have got to be kidding man??

JPrevost

Some of you just don't have a clue. Like ede said, 327, 302, they aren't great motors unless you've got a displacement cap in a racing class. Even then they aren't the best choices, especially not for reliable street power vs. cost!!!! It's common sence that if you can make more power without needing to rev higher you'll be more reliable. It's also common sence that if you can run a smaller cam and make the same or more power then it too will be more reliable. This is where the 350 rules. It's the cheapest option right now to make reliable every day power on a budget. With the falling cost of the stroker cranks the 383 is soon to be the king of the small block budget.
A 302 and 327 will not make more power and be more streetable than a motor with the same bore and more stroke!!!
Have any of you actually looked at the prices for a 3" and 3.25" crank lately? Then how about looking at the ever so popular 3.48" crank and tell me what is so wrong with having more cubes and costing less to build while making more power.
If I could find a 400 block for a good price you can bet your **** that would be in my car sooner than a 327 or 302. Ever notice how over the years as larger displacement motors have been introduced that the hot rodders have adapted them with open arms and big devilish grins on their faces. When the 327 came out the 283 was yanked and replaced....when the 350 came out the 327 found a new home, etc.
I have experience with the 283's, 327's, 350's, and 383's, soon a 400 if a friend gets enough cash to start building it up. I'm in no way an expert but it doesn't take an expert to understand that more cubes is always better for performance. Ask the NASCAR guys why they run ~355 motors and not "327's" or "302's" and you'll get the same reason. BTW, those NASCAR motors are spending a LOT of time beyond your daily driven cars redline.
Go read a book or listen to the guys that have experience. Just stop saying that a 327 is a good motor compared to a 350 because it isn't and never will be as reliable $ for $. I take that back, it could become more reliable $ for $ if every 3.48" stroke crank in the world had a virus and got sick .
My vote is for the 400 block if you can wait and find a good deal. If not, go with a 383 and if you're looking to pinch penny's...DON'T....just go with a 350 and save the money on the crank for better quality parts. You won't be disapointed with anything that displaces at least 350 cubes .

Low C1500

I wouldn't say that the 400 block is the worst sbc ever built, but as far as cooling passage design, it lags the 350 block by a fair margin. And has anyone road in a "done up" 305 in a mid size car (thirdgen), they just don't have the tourque once there cam'd up. My buddy's 377 really impressed me, as far as tourque, and high reving goes. It was a very similar engine to mine (but camel hump heads) but he had the thing on propane though, I took him out in a race by a truck length. But if he had an 850 DP on there the thing would have been CRAZZZZYYY.

F-BIRD'88

There is an old saying:

A man always ran faster as a boy.
Ah the good old days.....

I was there, the cars are generally faster now.
But to be able to buy 106 octane gas at the pump for your
12:1 cr 60's muscle car again......... and race right down Main Street he hee he and not have the cops bother to chase ya.

Miss my Big Block 68 Chevelle..... those were the days....lol

Build the 350 and dump the money you would have wasted on some stroker combo on a set of good flowing aftermarket heads.
Most bang for the $buck$ by far.

laiky

ad nausium, these posts kill me

iroc22

Definitely. Being witness through a drag race program we ran at my high school, I was able to view many different stroke/bore/rod combinations run on the dyno. The 3.48 stroke coupled with the 4.125" or 4.00" bore created the best sucess for power specific curves. The 3.75" stroke created great low-speed torque but lacked in everything else. I tend to believe that intake runner volume was not enough to greatly benefit that extra stroke. Even the tunnel ram we had I don't think was enough to feed it. Any of the single plane manifolds were enough to match any 6.0" rodded 355 we threw at the dyno.

Power does not equal displacement, it's the combination of the correct parts that creates the power. How come the 400 SBC was making 150hp in the mid 70's if it's such a powerhouse? if nowadays we have a 281 cid modular Ford engine producing 320hp at the flywheel? It's because all the right parts have been combined to create the entire package. I must admit though that the mid 70's 400 utilizied a smaller profile cam and the heads don't flow as well as the 281 Ford.

But whatever, I don't have anything against running a 400 SBC. Just make sure you check very close for cracks because they are the most prone to cracks out of all the SBC's.

JPrevost

You missed my point!
With all the same parts including heads, cam, type of intake etc. A bigger displacement motor will make more power.
Don't even compare mid 70's 400 blocks to a recent motor, that's completely off topic and has no point.
If you take vortec heads with a stock mild cam, slap them onto any of the engine combo's you listed I'll put money down that with tuning (big enough injectors etc) you'll make more power and go faster with the 400. Next would be the 383 and so on. The 305 is a freak, it's got a small bore and relatively long stroke making it not good for much, especially big valved heads.
How much money are you working with?

laiky

not true really, the power band would just shift higher up, you would make more low end for most combo's but it would come as a trade off for higher rpm power. For street use a wide powerband with good low end and the ability to make decent high rpm power is preferred. Right now i have a stump puller of a 383 but it doesn't rpm very well, i need to get a bigger manifold and a free flowing cat. besides at sustained high rpm there is an efficiency trade off.

If i had to do it over i would build a 377, if i had to do it over and as cheap as possible i would build a 350. if i had to do it over and get a really heavy car off the line, 400 ( provided i could get a really free flowinf exhaust) The 383 In my opinion was too much trouble to build, i only did it because i had the block and the Power but got me, i couldn't settle for anything less tahn the most power i could make. A 302 would be a gas in a light car, like a road racer but only with absolutely premium parts and a close ratio tranny, the TKO i'm using would probably slow it down. 327 is about 1/2 way between a 350 and 302. BTW 400 blocks do have some problems but outside of availability they are easily corrected by the aftermarket or GM since about 1980 or so. It is readily accepted that a 400 2 bolt is good till 450 hp with studs and such.
how about a .030 over 400 with a 302 crank??

that would be fun!

laiky

oh and BTW all you 400 haters that think they overheat , ever look at a bowtie block?? World products block?? they all have siamesed bores, you know why? they are stronger! and distort less under stress.

iroc22

I didn't miss your point, I've heard it over and over again on this board. If you put the same parts on a 400 and a 350, yes the 400 might have more peak hp and peak torque, but it's the power curve where it doesn't make it up. The shorter stroked, longer rodded engines make a nicer fuel specific curve for different purposes. The 400 even with the same heads/cam/intake makes all it's grunt on the low end every time, with very quick power peaks. This is what I've seen and that's why we ran the 355 in our race car over the 406, because we could properly match the engines power curve to the tranny and rear gears to the length of the 1/4 mile.

I don't know where the 305 came from, but I'm trying to dispell a myth about the 305. You can run 2.02/1.60 valves on them to about .550" lift where shrouding becomes an issue and interference doesn't occur until .580-.590". We mocked up a bare 305 block with those valves on heads with 64cc chambers. Haha with those heads we even managed 420hp outta a carbed 305. Pretty ridiculous numbers, but torque was around 370 IIRC.

400cidz28

Why can't a 400 use a roller cam and a 350 can? I don't know and I'd like to know, that's why I'm asking.

laiky

there ois a factory roller block where the lifters can be reused, they only made 350's and 305's never a 400. if you want a roller cam in a 400 its no problem it just costs more. same for a non-factory roller 350

Marshall89ws6

[QUOTE]Originally posted by bradkeith

Quote:

Originally posted by Marshall89ws6
[and plus 400 is probly the worst goddamn block chevy made....... 350 is good but common...... my favorite motors are the 327 and chevy 302 they both have a 4" bore like the 350 which is neccessary


You have got to be kidding man??

haha here let me explain this further for you before someone else gets offended by my opinions on certain blocks....... i'll take youthrough it nice and slow
-i dont like 400... no cooling for inner two cylinders
-i have a 350 motor .030 over in my car..... i love it
-and simply stated that my FAVORITE motors were the 327 and 302.... not many people have them and they can be just as fast as a 350 can unless u start talking about bringing the motor to its max, which the person who started the thread wasnt planning on doing when he asked our opinions....... yea more cubes is better...... but theres more than cubes, as someone else in the thread said.... design is a bigger factor for durability and reliability. now i hope i made myself clear.

iroc22

You can use a roller cam in a 400. Just get a retrofit roller cam from a company like Comp, Crane or Lunati.

iroc22

Looking at the results too, I can't belive the 305 got the same amount of votes as the 377

laiky

there is no cooling problem on the 400's

Vader

I kinda sux that we weren't allowed to select any big blocks in the poll, or I might have responded to it. I'm thinking a 535 would do nicely in a ThirdGen, without air conditioning or course. It has both bore and stroke. 110" drag radials? no problem....

rx7speed

I would think a 302 or a 327 would be more reliable for a daily driver



yeah you put more stress on the motor when you rev it up to 8 bazillion rpms


but daily driver you have less firction due to less of a stroke

Kingtal0n

<b>With all the same parts including heads, cam, type of intake etc. A bigger displacement motor will make more power. </b>

So wait... If I take all the stuff off my 305 and put it on my 400 it will make more power? well, thats what you just said! No disrespect but I dont beleive that myth.

<b>I would think a 302 or a 327 would be more reliable for a daily driver </b>

All respect to you as well, RX7Speed, but reliability in an engine has little to do with its size. You should know that!

<b>yeah you put more stress on the motor when you rev it up to 8 bazillion rpms
</b>

Heh, and how high do you spin yours? eh? Nuff' said.

Kingtal0n

say, lookie. what was the original question? hmm.. I think it had somthing to do with the words <b>"reliable"</b> and <b>"daily drive"</b>" and <b>"cheap"</b>"

If we break each word down into a specific engine bore/stroke size... which makes no sense but lets just do it for <b>fun</b> anyways.

reliable and daily drive. two words, 1 meaning. It means no matter which small block chevy you build, you want it to last as long as possible. This automatically, no matter what anyone else says, no matter who says blah... AUTOMATICALLY this means you should limit your RPM Power band to below <b>6,000.</b> Why why why?
<b>Any typicaly</b> small block chevy can spin to 6,000 on stock, cast, factory rotating parts. its true, dont deny it. what did i just say? repeat after me, <b>"I will not spin my stock cast chevy bottom end past 6,000 rpms"</b> okay, thanks.
like RX7speed said, they dont last long after that. yeah, subjective, ok, but still.
"But but but, <b>Why</b> cant my 305 or my 283, or my 307 or my 400 go past 4500 rpms?"
Well, <b>it can</b>. but since your heads/intake/cam/springs etc.. simply cant FEED the engine past that, well, you cant. but the stock cast rotating assembly CAN. Mileage doubting that is. dont expect an engine with 150,000 miles to goto 6,000 for the first time in its life more than a few times.
Anyways:
now we have our limit, 6,000 rpms. simple. this means you can use cast factory parts in your engine, it also means cheap. reliable? Like i said before, <b>engine size</b> doesnt mean reliable. <b>wear and tear, attention to detail, driving style, frequent maintanance</b>... those determine engine reliability on THAT front.
now, without forced induction, how much power you make below that 6,000 rpm goal is NOT up to your bottom end components... forged or cast, will make <b>little</b> difference in the way of horsepower output. what matters now, its cam/head/intake choice, among other things... attention to detail falls in here too.
see those two heads? one is a dart aluminum 220CC head with 2.08/1.60 valves and has been polished up. The other? Well, its a cast iron L98 head that has been ported a little and had a 3-angle valve job done. ah, which one will make more horsepower? The dart? Irrelivant I say. what IS relevant is to match the head to the rest of your drivetrain and valve train. Whats that? you have 2.77 gears, 1800 Rpm Stall, and a 274/284 Duration cam? Now which head suites <b>your needs</b> better? Uh huh... that L98 head is looking better all the time. Idle quality? Laf. that phrase isnt in Dart's dictionary. Fuel economy? Dont make me sick.
So bigger isnt better. the same goes for engines... usually. All things considered, lets cut this short before I start beating myself up.

Considering cheap and reliable, not to mention Parts availability, reputation, useability, Oh, and did i mention cheap?

Come on, somone tell me the "averageing" <b>cheapest/reliable/available/reputable/economical/well known</b>
Small block chevrolet that there is?

Im waiting...

83CAMAROMAN

With all the same parts including heads, cam, type of intake etc. A bigger displacement motor will make more power.


i think what he meant by that kingtalon was that if you have a 305 motor and a400 motor....and you put heads on the 305 that flow 20%better than stock and you put heads that flow 20% bettter than stock on the 400 and so on and so on with parts the bigger cubes willmake more power.....

not 305 parts on a 400....

its a ratio thing...well thats what i got from it anyway, i agree. cause in a blown out of proposion example....if displacement didnt matter for power.....frieght ships wouold all have one liter geo metro motors......like i said blown way out of proportion but it makes the point

JPrevost

Let me rechuck what I've said before in one sentance.
BUILD THE BIGGEST MOTOR YOU CAN AFFORD!!!!
BTW, a 400 block with 305 heads is just stupid, I should smack you for even bringing up such a dumb idea.
A 350 is perfect but the 383's are getting cheaper to build so I would look into them. A 400 block is great, only if you can find the block for cheap. A 302 and 327 are worthless in your case because you want to make power for cheap and a 350 is cheaper to build. Besides, why do you think the 350 has been so well adapted by us Hot Rodders? Why do you think a 350 swap is so popular!!!!

DTL504

iTrader: (1)

I will "SUPPORT THAT" smack him in the KISSER's for such a stupid Idea (SBC 400 w/ 305 heads.
Sometime thing is left better unsaid

Kingtal0n

<b>BTW, a 400 block with 305 heads is just stupid, I should smack you for even bringing up such a dumb idea.
</b>

Ok smack me! I was trying to bring up a point! but yes i deserve to be smacked. hey, on that token, your comparison:

<b>frieght ships wouold all have one liter geo metro motors</b>

is alot like mine!

ajm_shorty

Funny... I never heard of a CHEVY 302...Because 302 is a FORD MOTOR...A 305 is a CHEVY

ajm_shorty

305 heads on a 350 is a good idea...You get Really good compression that way... just get the heads ported thats all

JPrevost

Glad you took it as a joke because it was one . Nice to know not everything is taken seriously.
Yeah, well it's all fun and games when it comes to motor choice, some just seem to have proven themselves countless times and others are the ones that get replaced for a reason.

JPrevost

Chevy has a 302 just like the ford 302, only difference was the years they were produced. Chevy had the 4" bore 3" stroke first. Chevy has a LOT of engine displacements that aren't so common. You think a 305 is bad, there was a 3.5" bore motor at one point!

JPrevost

Just so long as they aren't the swirl port heads found on the TBI motors!!! That'll just kill all hopes of a "smart" engine rebuild.

laiky

if you can say you never heard of the chevy 302, you should leave this board, in fact you should have never come here!! Just so you know it debued in the 67 Z28, in fact it's what basically made the car a Z28. It was rated at 290 hp ( gross ) and was available with factory headers and a cross ram dual quad intake that the factory would happily place in the trunk and you could have the dealer install, with the aformentioned upgrades it was good for about 400 gross hp and 8000 rpm. Although not the ideal street motor, itwas required to be under 5.0 liters for trans-am racing. These motors in the penske transam cars ( traco built i believe) made the Z28 a legend. As has been posted many times in this particular board it was fast as hell but eclipsed by the larger displacement LT1 350, which was a better street motor because of its larger displacemnt that helped to move the powerband lower in the rev range ( still high by modern standards)

one other point, chevy built it before ford, they had the 289. it was only made from 67-69, and if they had used this combo instaed of the 305 the 3rd gens would be legendary too.

IROCZTWENTYGR8

iTrader: (1)

350 or 383. Thats all you need and the 350 is a great engine that can do it all and be reliable. 400's have had their issues with cooling and bore walls, but they have more ci. and if done correctly can be really good too.

rx7speed

do you have any idea what I was talking about when I said something about the 302 or 327 being more reliable


it doesn't matter engine size your right


but stroke I would think would have a factor in how reliable a motor is

a short stroke motor like a 302 or 327 would produce less friction, less wear and tear on the block, have a better rod stroke ratio resulting in less side loading of the block, and less stress put on the connecting rods due to the odd angle of a longer stroke block.

just taking into friction alone at 3000rpms for one min on a 3 inch stroke you move about 18000 inches or 1500ft

but on a 3.48 inch stroke you now in that same distance it is 20880 inches or 1740ft

that makes a difference of 240 feet of travel in one min

that alone is worth some wear on tear on the bigger motor

also can't forget that the longer stroke puts more stress on the crank, rods, and pistons due to higher pistons speeds as well
the 3 inch stroke vs the 3.45 inch stroke has piston speeds about 13.4% lower at the same crank rpm... if I did my math right ( wouldn't be shocked if I didn't being I'm half asleep)
and if a motor makes peak power at 8000 rpms yes it's not going to last there if you do it for 100k miles straight. but on a daily driver your not spending that much time up there. not like you would with a full out road race, nascar or some thing along those lines race car. so that is an issue yes, but not as much as the daily driven loads would that take up 99% of a motors life.
and as you said in here in the point I even bolded out... wear and tear which on a daily driven aspect you would get more of with a large stroke motor


and yes I rev mine up to 7000-8000 almost daily.... WITH 184K MILES ... and compression still checks out fine for how many miles are on the motor and everything else is still doing ok so I would say my motor is fairly relaible plus they are built for handling revs like that..... also the nature of a rotary motor puts the motors motion in almost perfect rotation rather then up and down motion like a piston motor. so therefor the stresses put on the motor from reving like that are less..... nuff said





what I said about putting the same heads, cam, and all between two motors the larger one would make more power was said without me further explaining it. my thinking was taking the 350 first build it up then build the 327 to match. both of them have different a/f needs and the 327 would be better built up for the higher rev range the 327 would have a higher potention to make power up high. plus I think a shorter stroke motor does have some other advantages in power production but I need to look into them a little further before I say anything.


you forgot to break all that down or whatever for each word... don't worry though I think I covered you on that one



you see what I was getting at though?

JPrevost

To reply to the above; Engine stroke has very little to do with engine wear. For one thing you don't have metal on metal so comparing those figured there is almost no difference. Another fact is that 80% of engine wear is during a cold start.
Oil will break down a lost faster in an engine making more hp, just look at the extream situations...top fuel oil goes in one color and comes out a cream green color that is highly toxic, then there is the geo metro which could probably go 40k+ miles in 3 months before needing an oil change. Another fact is that more oil in a system will last longer so add a couple quarts and you've probably made up the difference between a 302 and 350. Then there is also the fact that a 302 is more likely to rev higher than a 350 for daily stop and go driving. This will bring up more issues with friction etc. What you would need to do is take your calculation and work out how many rpms an engine see's in a daily operation and compare the 2. You'd be suprised what more stroke can do for durability and reliability (cough...diesel...cough). There are so many factors like forged pistons vs tighter fit cast and how that along is better for street. Personally I would never put in a loose fit heavy forged piston on a car that'll be making all it's power n/a and under ~425hp (350), ~380hp (327), etc.
Now to get away from the bench racing....look at the fact that a flat tap cammed 350 in a truck weighing twice as much as an f-body can pull and still get over 200k miles while some 305's can't even get to 150k. Don't just look at a specific reason without taking into acount all the other factors that go into this.
Again, 350 is the flagship chevy motor for some very good reasons but yes, some can argue that chevy should have kept the 3.25" stroke and just increased the bore...oh well! What works works

Low C1500

Engine wear is mostly due to cold start, but cylinder wear (not bearing or anything else) could be thought of as being proportional to stroke. The longer the stroke the more your cylinder will "egg" out.

titeride85

If anyone is still reading this post, I would go with the 400. Check out my sig. 400+ hp and 450 +/- tq. All for under $3000. Not to mention, it is extremely reliable, quick because of the tq, and it is comprable in cost to the 350. SBC parts are all fairly reasonable. I didn't aim for any race engine but it sure is fun to drive.

titeride85

By the way, the guys b!tching about side loads on longer stroke motors apparently haven't seen that longer rods reduce side loads and improve the rod/stroke ratio. So make a decision based on what results you want. Any motor you build will be worth it as long as you have fun with it. PEACE

Low C1500

titeride85,

SO you think a 383 has less "side force" on the cylinder walls at the bottom / middle of the stroke than a 350! Yeah right buddy, you've been sniffin glue again! At the middle of the stroke the rod is at more of a tangent with a longer rod.... more side force on the walls.

But rod lenght is minor, Comp ratio and piston ring chioce has alot more to do with cylinder wear.

86TransAMsbc305

350 all the way

ajm_shorty

I would go with the 350...they wear good and are capable of putting out some HP.

My equation for an engine is:

$$$$ = HP =

It all depends on what your looking for

86TransAMsbc305

I really like the 305's

JPrevost

Me too...when it's a 302 bored 2 over

rx7speed

you might not get metal to metal contact as you say but then how do you explain the cyl wall getting larger even if only by .01" or so. how do you explain any sort of wear other then the cold start wear? there must be some sort of contact betweet the cyl and the piston to create that wear. also the movement I quoted for the piston is not only just put on the cyl walls but the rod must take that extra abuse, rod bearings, crank, the little piston pin and all that also are going to be exposed to more g force which would create more load that the bearing has to take.


yes a diesel might have a longer stroke but only rev to what a whole wopping 2000-3000 rpms MAX. most of there driving time is spent at around 1500rpms or so isn't it? so it is not the stroke that is causing less wear but the fact that they spend so much time in the such a low rpm range.... .lower then most gas motors run.


I would think if you run nitromenthane in any car with any blowby what so ever you are going to mess your oil up very quickly. though higher temps, higher loads, high friction, and so forth will wear the oil down a lot quicker but you can't say it was just due to more power


that is not going to make for less wear on the motor just making the oil last a little longer


just b/c it can rev higher doesn't mean you need to spend time in that high rpm range. I would still think that the shorter stroke of a 302 or 327 would mean less wear and tear on the motor due to less friction

that is what I kinda did with the 3000rpm and taking piston speed from that

I agree forged vs cast the forged would work a lot better due to better fit and all

and cast pistons on a high output motor... wel that would be a smart move now wouldn't it

that could be due to a lot of reason.. how well ppl take care of the motor, what they do when they drive it like who takes a truck like that and goes out racing it, but if you are in some camaro you are prolly going to drive it a little harder.


there could be so many reason for that and with the way corp systems works who knows it could be for some other reason then wear and tear who knows......

rx7speed

you put a long stroke on a motor with the same rod as a shorter stroke motor you are going to create more of an angle which would put the piston more into the side of a block


would draw it for you but not enough time... will get back to it later

Kingtal0n

'nuff said. haha.
it was a joke man, about the rotary/rpm thing... a joke.... sheesh!

you guys are no fun
especially the ones who jump on one small error and are like "hey you dont know what your talking about! thats bull$#!t and you dont know crap!"

Well dont take it personally but its all in good fun on my part
If i **** anyone off just cause I wrote somthing on a webpage in the middle of no where (ok, on somones harddrive) your taking this too seriouselly. I cant think of how many things I have read or seen that were totally crap! but you know what? Maybe to the person that wrote them, they ARNT total crap. Maybe, just maybe, we are stuck on theories and ideas that some engine builder or top fuel dragster racer dude or some huge corporation (GM) came up with, that make sense, but are total crap.

As technology progresses, ideas and things that "work in today's motors" may become totally moot in the next generaiton of engines. We may find out that heat isnt the cause of detonation, but some small fragment of meteor that is created and destroyed under the severve cycles of the internal combustion engine. You see what im saying? Just cause I read in a book that longer rods pro-long engine life, doesnt mean its true, but it doesnt mean its wrong either. Just cause I read somwhere that superchargers add horsepower because they compress air doesnt mean its correct, but it doesnt mean its wrong either. Did i make my point?
We can say what we want, and we can even theorize and try it out, and even if we think we are right, there may still be some other variable, some inconsistancy leading us in the wrong direction. yeah higher octane gas is cool right? it lets us use higher compression ratios without detonation right? maybe not. maybe its some additive they put in the high octane fuel and alchohol that lets us run hotter without detonation. who knows? Even though they have tested and tested and researched and tested, a fact becomes total crap when they realize they were looking at it from the wrong perspective. and maybe elvis isnt dead either. get my point? and if i **** anyone off because you chose to read my tirade, more power to you. cause maybe your right, and im wrong. or maybe not.

titeride85

RX7...if you put a longer stroke in a shorter stroke motor, you will create more side load. If you put a longer rod into the short stroke motor with a longer stroke (i.e. 383=350 bored .030 over with a 3.75 crank, 6.000 rods will have less side load than the 5.7 rod) you will have a side load comparable to the standard 350.

Do you understand those basic mechanical/geometrical principals? Or are you too busy playing with your wankel and trying to prove how smart you are?

Here: The maximum point of side load is when the crank is perpendicular (90 degrees) to the cylinder centerline.

Given: The more accute the angle of the rod to the cylinder centerline, the less wear the cylinder and rings create.

Given: A^2+B^2=C^2 and Tan a=opp/adj

So a 383 or 400 w/ 6.0 rods: 36+14.063=50.063^2 > 7.075
Next: Tan a=3.75/7.075=0.530 > 0.530 Inv tan=27.925 degrees

Now a standard 350: 32.49+12.11=44.60^2 > 6.678
Then: Tan b=3.48/6.678=0.521 > 0.521 Inv Tan=27.52 degrees

That says that you have less than half a degree larger angle with a longer rod and longer stroke. So if you are ignorant enough to give up the cubic inches and the torque it creates for less than half a degree (which will not be much extra wear at all), go ahead and be ignorant. :rockon:

Edit is to also make the same point to Low C1500. I didn't want to leave anyone out that is trying to make me the fool.

Low C1500

titeride85,

You are a fool, and I like how your changing your statement now to say the wear will be equal, not better, by changing rod and crank length. And don't post math eqautions from high school either. And yes keeping the crank the same and putting in longer rods only will cause a smaller tangent angle.

You know you wouldn't get negative responses if you didn't attack people in your posts.

Kingtal0n

<b>Or are you too busy playing with your wankel and trying to prove how smart you are? </b>

Hey, now Wankels are the coolest things I have ever seen. He only plays with them cause... well.. they are the coolest thing I have ever seen. i Imagine theres a lot of geometry and math crap that goes into the design of one of those things, too. but when we build a small block (or a wankel) we dont whip out a protractor and go at it... no sir... we just put it together. the only math we use is torque sequences and bolt patterns and stretch guage readings... occasionally we CC the combustion chamber and degree the cam...

If engine building was such a pain in the @$$ to complete people wouldnt do it as much. It wouldnt be fun. Combinations other people use to make winning numbers are part of our "math".

Why do people build 383's? I doubt they say:
They say somthing like "MM... torque... torque is gooood..."
Which to me sounds a bit less "theoretical" but non-the-less has been proven time and time again.
I doubt the stresses imposed by any rod/stroke combination will necessitate a rebuild any sooner than otherwise observed. What I mean by that is if the 383 wears .2% faster than the 350 im sure somthing else will break first, leaving you not caring about that extra .2% of wear. I mean youve gota bore it anyways right? Hell, I know I would.

rx7speed

[QUOTE]Originally posted by titeride85
but also I think I said something along the lines of there is more to this in the wear, tear, and stress and so forth then just rod/stroke ratio. and how is it being ignorant by not adding more cubes? maybe I´m someone who likes the hard part of making more power on less motor.... or maybe I know that adding cubes is not the only way to make power but that more cubes is only a tool to do so? maybe I´m a man who likes small motor turbo package does that make me ignorant? or does that make you ignorant thinking only a larger motor is the only way to make power? sorry if I come off as sounding like an *** but you more or lesswent forth and tried to make it sound as though I know nothing, you flat out said I´m ignorant and you on the other hand make two different statements and yet you are the one who is trying to make himself sound like all high and mighty while doing name calling

kinda like your statements that are posted below
Do you understand those basic mechanical/geometrical principals? Or are you too busy playing with your wankel and trying to prove how smart you are?
think I already covered that part below
go ahead and be ignorant.

I didn't want to leave anyone out that is trying to make me the foolif you mean by showing your own contradiction then that´s your fault. if you mean for trying to learn and help other ppl out.... well that is a part of learning you don´t need to be an *** over it

but for the most part the whole post came off as that way...if I´m mistaken then I´m sorry.





but let me quote this from you
and here is what I said
sounds like they are the same thing to me

I was saying that a longer stroke will make for more side load
you say the same thing.... but I am the stupid guy?

but yet on your first statement you contradict what yo uare saying now... to point out your first statement in which you say a long stroke will reduce side load?


alll in all though I say we just drop it... I got my say in so did you... I would rather not get this post locked with some of the info in here... it wouldn´t be worth it.

rx7speed

double post sorry

rx7speed

hey I´m not pissed just razzin you as well . you should know by now you can give me crap it´s just when you come off being an *** when I have no clue who you are then I get a little iffy about my actions.... or when someone calls me **** or thinks of me as such

hey man this is learning you dont need to know your s<x>hit just to say something. if your wrong (as we all are sometimes) you learn from it
agreed whats life without a little fun.... just look at mark and I (that da<x>mn post *****)

I know how that one works... rotaries had a bad name only b/c ppl who know nothing about them go off on them only b/c that is the idea they believe and are unwilling ot learn anything else..... if t hey learn though that is cool... learning in life is grand

As technology progresses, ideas and things that "work in today's motors" may become totally moot in the next generaiton of engines. We may find out that heat isnt the cause of detonation, but some small fragment of meteor that is created and destroyed under the severve cycles of the internal combustion engine. You see what im saying? Just cause I read in a book that longer rods pro-long engine life, doesnt mean its true, but it doesnt mean its wrong either. Just cause I read somwhere that superchargers add horsepower because they compress air doesnt mean its correct, but it doesnt mean its wrong either. Did i make my point?
We can say what we want, and we can even theorize and try it out, and even if we think we are right, there may still be some other variable, some inconsistancy leading us in the wrong direction. yeah higher octane gas is cool right? it lets us use higher compression ratios without detonation right? maybe not. maybe its some additive they put in the high octane fuel and alchohol that lets us run hotter without detonation. who knows? Even though they have tested and tested and researched and tested, a fact becomes total crap when they realize they were looking at it from the wrong perspective. and maybe elvis isnt dead either. get my point? and if i **** anyone off because you chose to read my tirade, more power to you. cause maybe your right, and im wrong. or maybe not.


dude too lazy to quote that on this spanish keyboard.... to damn tough but your write not everything is right and wrong... but some things that are sure enough now to make them as fact. granted there is still a lot of theory in motor building though