I read and read on destroking getting bashed. But the reason why I want to use a destroked motor is to get in the higher powerband faster. A destroked motor should rev faster am I correct? Im going with an intercooled twin T04 setup with 8.5:1 compression. Shes gonna be a dog off the line especially with ported turbo housings even if I go with a 383\396 im thinking. I think that a destroked engine will be better at the high rpms I want to spin for the turbos (turbos like rpm) and it will get "up there faster."
Im not a quarter mile guy... im a ***** at heart Im a fan of the roll on
im sorry!
Im an track and freeway guy... So the topend is what im concerned about. So I was thinking about taking a bored out lt1 block and destroking it to 327 (333 bored out? idremember)
This should give me alot more usable power up top for 7300rpm sprints? (yes I know im gonna need studs and an aftermarket computer)

 

why not just build a 327.....
P.S. 336ci

 

What makes you think a 383 wont rev to 7300 with ease?
What makes you think a 383 will be a dog off the line? I dont even know what to say to that, my stock 305 will kill the tires off the line, all a bigger engine will do is make it worse.

Just build the bigger engine. More cubes=more power, period. All destroking will do is kill power. If youre worried about RPM range, just choose the right cam for your 383 and it will rev just fine thank you.

 

A 350, 327, 302, and 383 block are all the same, a 327 bored out 327 will vary depending on how much it is bored. You would be able to rev the snot out of a 327tt lt1, so make sure your bottom end i bullit proof. Make sure you go with a manual tranny(t56) and really high rear end gear(4.11 or higher). That setup would be very fast, and if you let the turbos spool up before your launch, you could expect low 11's, or even 10's depending on your traction, rear gear and how well you can drive.

 

I am on your side nickerz, and I am not alone. Here is a great article on building an engine just like your talking about from the AFR website: http://www.airflowresearch.com/artic...le03/A3-P1.htm .
Dyno numbers don't lie! They mention numerous benifits of an engine of this design. I can just imagine what that combo would do under a tpi manifold!



This post makes me a senior member!

Boo-yahh

 

Long rods as important as, perhaps more important than, stroke for a high rev'n engine. Even more critical, the total "package" must work together, or you'll suffer somewhere along the road.

Accept that, and now horsepower vs. cubes is - the more you have, the more you get.

 

here we go again....:lala:

 

I dont care what anyone says ,a 383 fits in the same category as the 305.I would suggest the 327 or even the 302 for high rpm working range.The only thing that i see will be your problem is compression on the destroked motor,meaning that your going to need a piston with a dome to have a good compression ratio of at least 10.5-1 and up.The dome hinders the flame front...so your going to have run a little more lead than if it was a flat top piston.the money you would spend on stroking the motor could instead be used on the cylinderheads,cam,pistons,etc.
dave

ps 383`s are a joke.

 

Well I'm no expert but.... cubes are cubes...
Hence I'm building a 496 BBC for my '84
This arguement will have no winner cause there is tons of ways to make more hp's....(turbo, supercharger, n2o for examples)
If your gonna talk apples to apples...more cubes will make more power....
reliability...that all depends on the parts you choose to buy.

 

a big engine can spinn like mad too but it will be pricey making it bulletproof when you figure out the rod velocities. '67 and older 327s = stock steel crank = save you some money on parts.

 

You must know one sorry engine builder if he can make a 383 as sorry as a 305. I have many circle track racing guys who run their 383's into the 7000 r.p.m. range without problem, and they win. Just out of curiousity how many 383's have you owned/built? If you want to spin faster the most important thing is to lose rotating mass, i.e. lightweight crank, rods, pistons, and lighter valvetrain parts. Good luck!!

 

Tell me which engine will have a faster piston velocity at 7000... a 327 or a 383.i do not want nor plan buying or building a 383, as i said before its a waste of time and money. stroking does not equal more power just more money.
dave

 

Originally posted by daverr O.K., right. You can build a very inexpensive stroker quite easily if you price around. How many 327 or 302 rotating assemblies crank, rods, pistons, bearings, rings, balancer, and flywheel can you buy brand new and completely steel for $900? If you want something to spin very fast reliably and cheap then use lighter parts. Yes a 327 is a high end engine, very little bottom end, but a 383 can do the same and it can also make tons of low and midrange torque. I spent a total of $2500 on my 383 and it is the best smallblock I have ever built for street use. For what NickerZ wants a 327 would be perfect, but without the turbos you could never match the power of a 383 with a 327 with the same amount of money involved in both.

 

He's planning on turbocharging the engine. That's why he specified a compression ratio of about 8.5 - 1.

 

Does everyone always forget about the 377? Man it's a high-revving, big cube motor. Isnt that a blend of everything?

 

377's are sweet as are 391's though they are very expensive to build.

 

I hear you about the 377. My dad had 12/1 compression one in his 69ss camaro backed up by a 4speed T-10 and 3.73 gears. It had well over 500hp n/a. Too bad he sold it when i was still a youngin.

 

my dad sold his 69SS 350 Camaro when he was a youngin too

 

So what parts am I lookin at (internals) for a 377 LT1? Is that a an overbored 350 with long rods and short stroke? I need to go with long rods to fight off detonation. I dont see why all these guys are going with non-intercooled, stock bottom ended, stock static compression turbo lt1s. Just askin for trouble in my opinion.
-Nick :hail:

 

377= 400 block 350 crank

why do you want to build an lt1?

:nono: optispark :nono:

 

jamesbern > I agree 100%, anyone who says that a 383 is junk hasn't seen a 383. Both my brother and dad have had an awesome experience with 383's; my brother run's a Nova II with a 383 with 9.5:1 compression and he loves it. My dad races IMCA modifieds; the class was formed MAINLY for the avid racer, and not the jerk that has the bigger checkbook, so 383's are all he runs. They're easy to get ahold of and are a dime a dozen. They're what racers call "Gorilla Killers", because he can run a mid ranged 383 and still kick a 400 or bigger down the block.... Yeah, he does run alcohol, and between 11 to 13.5 compression, but all lack roller cams and all that other high dollar crap. If you ask me, 383's are the only way to go.......
If you want to be able to rap the snot out of your motors and do it quckly, invest in a good roller assembly.....

-Tyrell

 

377 also = 400 crank in an unbored over 350 block.

You can get rid of the optispark if you want. 3rgens have room for the distributor unlike 4thgens. www.lt1intake.com

 

Well im picking up a 327 with longtubes from a buddy that rapped his monte carlo around a tree while he was drunk. Man I sure do have alot of friends that crash ****! Anyways it should put out about 335fWhp with the longtubes, open element air filter with K&N lid, bullet mufflers, and some good tuning.
I dont have money for the FI route yet, but my next mods will be 3.73s and a nice stall converter. Good for high 12s im hoping. Itll be nice to go from 15s to 12s
:hail: Nick :lala:

 

i say forget about all the above for a moment. i know 2 people who have taken a 350 block and tehn jsut used a 327 crank wth the larger main journals. then that away you still have decent cubes but then you have a shorter stroke so that u can rev teh crap out of it easier. on of the people is a 18 year old i go to school with that has a 68ss camaro that ran 12.2 before his engine fire(damn NOS) but now he is rebuildign it with duel holleys anyway the other person is my cousin that has a 72 nova that is able to rev to about 9 or 10grand he realy dont knwo cause he burrys the needle on his 8grand tach along time befor hes out of revs jsut thought id throw that option at ya. by the way the nova ran low 12s all day long. not to bad for poor boy racing down in missouri sticks

kolby

 

That article on the AFR website about their "better" 350 seems quite odd.

First of all not all the theory seems correct to me.

longer pause at top dead center=less chance of detonation?

I'm not sure about that, I think it's the opposite.

If they wanted to do a proper comparison between longer rods and normal rods they should have had an engine where they only changed the rotating assembly. Not the heads.

The aftermarket heads which they put on that engine have a far greater impact on allowable compression ratio than the rod length will.

Pretty crappy article in my opinion.

 

377s are expensive to build?!

bwhahahahahahah

now thats funny

stock 400 block = $200
get some cheapo forged pistons= $350
decent eagle rods (6") = $400 or cheaper from ebay
GM forged steel crank = $400
bearing spacers = $100

boy that sounds expensive to me

now that is a BUDGET built motor for high hp, you could easily do it cheaper using a cast crank or cast pistons.

Can someone tell me what F1 motors use as motors?

oh yeah, thats right BIG BORES and SHORT STROKES

a 377 can make some helacious power if built correctly. the only problem is that now you make that power on the WAAAAAAY top end. so 377s are PURPOSE BUILT motors for either small cube classes OR a drag radial class

i have a friend with a 377 with the combo above with some Dart Raised Runner heads a huge nitrous cam and goes 10.30s ON MOTOR with a nitrous cam. Throws in the 250 pills and it goes 9.dohs

another friend with similar combo but dart iron eagle big runner heads (230cc) goes 10.70s on motor and 9.30s on the same pill

 

Thanks! 89ProchargedROC, but most people I know would like some heads, on their engine along with gaskets, an intake, a cam, rings and bearings are sometimes a good idea also. So let me refigure this then: We currently have $1450 in the shortblock, but we need heads; cheapies are about $600, we need gaskets rings and bearings; figure $100, an intake we'll go cheap $100, also cheap on the cam $100. That brings the total to $2350 exactly $350 more than what I have in my 383, reasonable, but not cheap. Just a small point, but my engine is all roller, yours is not (say by to at least 50 horse). If I removed my roller cam and rockers my engine costs $1400 to build, that my friend is a budget engine. We can just assume that the $200 400 block we bought from John Doe is in excellent condition, a great idea for our racing engine. The point I am making is there is no such thing as a cheap, reliable racing engine, the big parts are cheap, it is the small stuff we forget and it adds up quickly. If $2000-$2500 is cheap, then I am wrong, but not many people I know have that kind of money that is totally expendable.

 

well cheap is defined by everybody as something different

the only thing i'm trying to prove james is that you can build a 377 for the same price as another destroked motor

thats it

if you want to point fingers and say well it isn't a roller engine.....then whoopty doo. Yes you'd need to buy some roller lifters

BUT

you can get them cheap on ebay or even used at an affordable price

 

Well, your initial reply came off pretty smart-$ss sarcastic towards my comment implying that I don't know what I am talking about, that is not at all accurate. My point wasn't the fact that my engine is roller and yours isn't, its the fact that mine was cheaper and my cam, rocker, and lifter combo cost $550 and yours was assummed free thus overinflating my actual cost. I don't B.S. anyone here for any reason, what would be the point? My actual post was that you could build a 383 cheaper than you can build a 377 or a 391, if you don't believe me then look up some prices in magazines. You can purchase a complete 383 rotating assembly for $450, 377 is about $600, and 391 is $750 all from the same people, it is quite clear which one is cheaper. I don't come here to argue, but if you don't have the facts or you accuse me of then I will. Just to justify, you can't just buy roller lifters and have a roller engine, you also need a roller cam which costs about $240 new and roller rockers mine were aluminum and cost another $150.

 

It's funny how all the older guys and proven/respected members all say the same thing....more displacement and the cam determines the rev/power range...amazine. Yet nobody listens or if they do they think it's wrong.
A cam is the only thing you need to adjust to build a high reving motor and a 383 is only going to make more horespower throughout the power range. Stick the same bump stick in a 283, a 302, 305, 327, 350, 383 and tell me which makes more power at every operating range. Now if you start talking about crazy off-road 1000hp small cube engines I'm going to tell you to stop comparing apples to oranges. A formula one car , yeah, let's talk about their bore to stroke ratio and then let's think about how they are reving to over 20000 rpm right now. Or you can compare those 8 and 9 second 1/4 cars to your car and get a MUCH more accurate estimate of what a similar engine would do for performance in your car.
As for the destroked 400 block...what a joke. I think destroking from 400 cubes to 377 is about as bad as taking a crappy 3.5" bore small block with it's stock 3.48" stroke and slapping in a 283 crank (3") for a whopping 230 cubes of high reving power. Sounds like what an import motor would do...take a nice large displacement engine and make it "rev to all hell" but have no power . You and your stupid rpm ranges...it's been proven before that a 383 doesn't have any less high end power, it only has MORE low end and mid range which makes it's hp slope a lot less radical. A wild 302 and similar small displacement motor usually has no power off idle and requires 4000+ rpm to start to "pull hard", this can be fun if i drove a crotch rocket.
Show me a guy that destroked his 400 block to 377 and is making 500hp and I'll show you the same engine with similar mods (and cost) into a 427 and guess what...it'll "rev" and wipe it's *** with the 377. Bottom line is don't destroke, only stroke, it's the same as a bore. Don't make it smaller, make it bigger!!!!
Again, the rpm operational range has very little to do with the bore:stroke ratio with large motors as it does with weight of parts and most importantly the cam selection. Oh yeah, and don't forget that a large cam in a small motor makes for no fun on the street yet the same cam in a larger motor will be more mild.
Everything is against destroking and only somebody that has lots of money to waste would destroke a motor. Either that or they have some rules that limit the displacement in their racing class.
I'm not sorry if I offended anybody, tuff, go cry me a river and bark all you want but I'll listen to the guys that know, build, and have proven to me that they know what they're talking about. As of right now I don't see anybody saying that a 302 is better than a 350 and we all [should] know that a 350 is only a stroked 302/327 so now what? Who's going to tell me tha a 302 can rev higher than a 350 and then argue that a 350 can't rev to 8000+rpm

 

Amen to the above post, I agree 200%.

 

NO offenece fellas, but this post is re-fuc'n-diculous!

You keep posting your ideas of the best engine, stroked, destroked, big-cube, small cube, gas, alcohol, rice... The botom line is there is no best engine or cam or heads or displacement. If there was it would be in every new car to roll off the line. Anyone who is seriously considering a build needs to put together a list of what they want their engine to do. High end horsies, low end torque, economy, octane compatability, and amount of use are just some of the things at the tip of the iceburg. Once you get together a list of these desired traits, then you can go ahead and argue about the best way to accomplish this. Nickerz started off this post by giving you guys a small list of things like this, and it didn't take many posts before you all lost sight of the target.

Not everybody wants the same thing, and this post is about what nickerz wants; so why not help him get it. This endless debate of the perfect engine should have it's own, mile long, post.

Drastius - I think you missed the point of that article bud

O.K. I feel better now. Proceed to talk trask about my post.

 

Maybe, perhaps you can clarify.

It sounded like they were saying that GM screwed up the connecting rod lengths, and they made it much better.

 

Here is your clarification, sorry but I'll have to get technical. I don't think 'screwed up' is a good way to put it, mabye you could say they failed to optimize the rod ratio. By utilizing a shorter stroke the piston spends more time at all positions of its travel at any given rpm range, it's not much but you have to realize when describing the motion of an engine you're dealing with fractions of nanoseconds. You are right, this alone doesn't prevent detonation. The fact is though, in technical terms an engines combustion can be considered an impulse, my dynamics prof would be so proud. The principle of work-energy states that for a body to change its potential or kinetic energy it must be effected by one or multiple impulses. These impulses are just a force multiplied by a length of time. The longer the time, the greater the impulse, the greater the effect on the body in motion. A common example of this is the length of a gun barrel. The longer the barrel, the longer the time the force of the charge has to act on the bullit, the farther the bullit goes. So back to our destrocked engine. Basically what that article said was they could assemble a mild 350 that can run on 87 octane and not detonate that would make power at levels of not-so-mild 350's that would have a problem with detonation at that octane level. There are also many more advantages to a engine of this design. For one, the larger bore of the 400 block allows better flow past the valves which we all know is worth some ponies. Simply put this engine is more effecient than a standard 350, it will make more power with the same amount of fuel. Ya know gm has been wrong before.

I really do think this post is way to far off subject though.

:lala:

 

Well then judging by what you just said, I think I did get the point of the article.

By all means the bigger bore=bigger valves is a good thing.

But there are a few problems with the theory.

A longer barrel allows a bullet to be shot faster/farther because the expanding gasses have longer to act on the bullet.

But when you apply that analogy to the destroked engine, it doesn't make sense to me. Your saying you make more power with a shorter stroke? According to your gun example, you should make more power with a longer stroke?

But back to my original post, I said that the article was not very good because it was implying that by putting in longer rods, you had less chance of detonation. It claimed that the piston stayed at top dead center for longer which helped prevent detonation.

The truth is that the opposite is true, the faster your compression stroke occurs, the less chance of detonation. This is because the faster the stroke the less time there is for the air/fuel to heat up.

Like I said before, the change in rod length would hardly affect allowable compression ratios at all. It was most likely the fact that they put on some better heads, and piston.

 

I would build the ultimate destroked engine for those twin turbos, a 321. Take a 400 block and use a 3" crank. This thing would rev amazingly fast and high especially with turbos, and make extreme upper-end power.

 

Why would you want to take away 105 cubes of enginde displacement to "move" the powerband a total of maybe 200-300rpm when instead you could be making LOTS more power with a 427 and low compression!
The idea of a smaller stroke is a joke, it's fubar and the perfect engine isn't only dependant on the power adder, or the weight of the car, or the conditions....it's a big fat package called the "big picture." Since nobody has been able to make LESS power with a larger motor I'd have to say this destroking stuff is a farse. I would only consider destroking if I had class rules and regulations OR I was smoking a crack pipe from the time I won the lottery and built the motor!
Yes it would be unique, yes it's different, but physics is against you. The difference between a 3" and 3.5" stroke isn't going to effect the max rpm range but instead it'll effect the kind of efficiency the engine will have below a certain rpm. That's why I said the 383's will feel more powerful all over and the 302's feel like they only come alive until 4000+. This is also my belief as to why so many guys think carbs are so much faster....and why I think 99.5% of members don't know jack about how to measure power. I can only imagine how frequently some guys are slapping on flowmasters and thinking they'll go faster....it's all about the SOUND. They hear it louder so they think it's faster. A carb will pop and crackle through the exhaust more likely than a similar EFI setup...the sound fools em. A carb is also pretty restrictive and EFI will make more power below the peak torque and horsepower so you'll notice that an ill carb might feel faster because it starts to rip and roar but has no power below ~2300...it's funny how we as humans don't take into consideration all the variables involved in tuning and performance related issues.
Again, if you destroke you're more likely to be highly disapointed than if you stroked the motor. I will say one thing though in defense of the shorter strokes, they're fun because of the fact that they don't have as much power. This requires them to spend more time at redline than other better designed engines. Personally I would like to have a 454 small block single large turbo. 4.2" bore and a 4.1" stroke 7.5:1 compression dished pistons with the longest rods possible. Some nice large valve heads and a custom grind cam designed by me. It's a secret right now but I hope to have a variable duration/lift cam aftermarket kit availible for a small block and yes, I've already got the mechanics worked out for the most part. Just need the money and the desire. Imagine a car that gets 30+ mpg on the highway and runs a solid 10 seconds. Of course I'd be using some 32 valve dephi heads or AFR with that new variable lift ratio kit if I couldn't afford the 32v's . Wishful thinking but it'll be powered by some wicket EFI and I'd be a VERY happy man if it all gets done before I die .
Think about it, why would you want to say you've got a 321 motor when you could say you've got a 454 small block .
Almost forgot...that whole thing about an engine reving faster than another...it's , in reality (not bench racing) a higher stall speed converter is the only way you would be able to rev "faster".

 

I am done here, this post is over so here is my view of this post: NickerZ was misinformed by someone of the benefits of destroking versus stroking, myself and a few others tried to give him the correct information the arguments started. In the process of informing him of the correct info, a few smart#$s members decided to show what they know from second hand experience and magazine mechanics. I really don't care at this point who is offended, if the above shoe fits wear it. If you don't have any firsthand knowledge, like actually building and racing one of the mentioned engines, then your input leaves a lot to be desired. I never said that a 383 is/was the best, even I don't think it is. If I could build a 496/502 that would be the best. Destroking is a waste of money in every case except for class rules in racing. I also agree with JPrevost once again on how most people don't know power, my carb is better above 2500, but anything below F.I. would be better.

 

Well, as I suspected this turned into a flamefest, for what I really think was no reason. I guess some people are just on the edge and take things too far.

Edited and locked.

 

Points taken. Post edited, sorry.