VashtheStampede

I have somewhat of a moral dilemma. Whether to a 350 and stroke it up to a 383 or to get a 400 and destroke it to a 377.
I would like to know your guy's opinions?

RB83L69

How about including the right answer in your choices....

Get a 400 and don't destroke it.

VashtheStampede

lol...ok and in your opinion why is a 400 the best answer?

unknown_host

iTrader: (1)

What do you want to do with the motor? I would say:

400 > 377 > 383

FSTFBDY

iTrader: (33)

If you can get a 400block just stroke that.
412cid.

Im in the middl eof doing a 400+cuber and Im debating if I should buy a stock stroke or a stroker crank. Either way the forged eagle crank is the same price. So Im leaning twards just stroking it.

top it off with my Twin turbos I already have and It should be one hell of a motor.


Deff. go for the More Cubes if you can get the 400block.

87F383

My opinion would be to use what ya got...I had a 350, hence I have a 383 now. If I had a 400 I would have stroked that. Cost effective HP...if there even is such a thing.

VashtheStampede

Just remember if stroke a 400 its going to lose some torque. You can just destroke it and get even more power out it. A stroked engine doesn't always put out more HP and Torque. There are trade offs you just have to decide for yourself.

unknown_host

iTrader: (1)

I have heard from numerous racers that motors with a long stroke dont like power adders as much as with a short stroke.

Whether this is true or not, I dont know. What I do know is if you look at some of the fastest cars in the NHRA, they are all enormous bore, small stroke power adder motors.

Fast time motorsports has a 8 second Corvette (i think its fast times) and it is a 335 if i remember correctly?

unknown_host

iTrader: (1)

A 400 isnt going to lose torque by stroking it, it may not make the peak torque a 377 will but it will definately make more avg torque.

scottland

LOL thats just about the biggest steaming pile of BS i've ever heard.

whoever told you that had no idea what they were talking about.

never sacrifice cubic inchs. build the largest cubic inch motor you can under your budget. the ONLY reason to destroke a motor is if you are running in a class that has a CID limit.

a 400 WILL make more power than a comparable 377, there is no question

more cubic inchs will equal more torque across the whole RPM range, which translates to more horsepower as well.

i have no idea where the misconception came from that, short stroke motors rev better for higher rpm, and longer stroke motors make more low end torque, or that destroking will make more power.

why do you think 383's (a stroked 350) are so common. its not because they make less power, its not just because people like being able to say they have a 383, it because they have more potential for power.

VashtheStampede

I found a site that has a list of 108 different combination of engines and parts that range from 305s to 427s that have been dynoed. And if you looked at each different combo you would notice that the 350s and the 383s pull out more hp and torque than the 400s and up, with a few exceptions. None of these engines have been turbo or supercharged.

25THRSS

I agree 100% with everything this man just said. Listen to him!

25THRSS

the only way to make a valid comparision would be to put the same heads, cam, intake manifold, carb, etc on each engine and tune it to it's liking and the largest cubic inch engine will always make more power period!

25THRSS

Did that site list this engine?
http://www.steveschmidtracing.com/ssr_089.htm

Or any of these?
http://www.autoshopracingengines.com/engines.htm

Notice how the more CI, the more hp and tq. See a trend going on?

FSTFBDY

iTrader: (33)

You cant compair a 20k dollar 434 and a basic 350. come on now.


Now this is a Nice Basic 408
http://temp.corvetteforum.net/c4/ski..._mods_page.htm

That ran 11.14's Naturally Asperated. 436RWHP and 500+ FT LBS

Very easy setup to mimic.

The Only reason I see you wanting to do a 377 would be if you wanted a High rever. and Even them build a 406 right and your good to 6k. How often you actually gona use more then 1/2 throttle in a 500HP motor on the street.

I know any more then 1/2 in my 383 on the street would put em up in a blister of smoke.

mw66nova

iTrader: (13)

depends on the poweradder. all of the forced induction people i talked with said a long stroke, smaller bore (like a 383 or a stroked 400 ie 427/434/454) are much easier to tune and are much more consistant. ray sanchez's new camaro is a short stroke motor and he is having a serious problem with consistancy. like one pass will be absolutely blazing speed and the next will seem like the car can't even get out of its own way. after changing nothing during the break between rounds!

VashtheStampede

Ok, I'm looking to swap my 305 for a bigger engine. I'd like to get a fair amount of power out of it, but I 'd still like it to be street drivable.What setup would you suggest I get in order to do this? And in your opinion is it worth it to install a turbo or supercharger.

mw66nova

iTrader: (13)

it is worth the trouble to install some type of forced induction, however, for your needs a medium 350 will do just fine, add a p1 procharger for about 500 streetable hp...

Dustin Mustangs

iTrader: (1)

Lets go back to high school phisics here with F=MA. The F (Force) is what breaks an engine that is reved too high. According to the above equation we can lower this F in two possible ways; lower A (acceleration) or lower M (mass). We all know that there are ways to lower M, but for this argument lets concentrate on A. One revolution (as in revolutions per minute or RPM as you said) involves the piston going up and down its given stroke exactly once. Considering the exact same RPM, this stroke has the exact same amount of time to occur regardless of stroke. So, if you have a longer distance to go in the same amount of time, you have to travel at a faster speed to get it done. Speed (as in piston speed) isn't a problem until you approach either TDC or BDC at which point you have to come to a complete stop and reverse direction.

Long story short: Faster speed + stop + faster speed + Stop...= Higher acceleration = Higher A = Higher F with M the same.

Therfore, a destroked shortblock can rev to a higher RPM with the same force acting on its components. I guess you can just save yourself the mis- and call it a conception now if you want.

This one is a bit easier to explain, but again it all boils down to basic phisics. I'll use another equation to make my point: T=FD. Torque, T, can be increased by increasing F, force, or D, the distance from the center of rotation at which that force acts. Both of these are increased when stroking a motor. The F goes up because your displacement goes up and given the same volumetric efficiency will produce a bigger F. The D goes up due to the larger stroke on the crank, and this is the unique advantage that stroking a motor has.

Long story short: It's easier to open a paint can with a screw driver than it is with a penny because D is longer and you can develop more TORQUE.

Therefore a stroked engine will make more low end torque, more high end torque and more average torque (again to to make it a fair comparison VE must be equal).


Now, as far as the original post and, for that matter, poster; Vash, what are you looking for out of this motor (ie. how much target HP, TQ and what RPM do you want it to happen at)?

BlackcamaroIROC

I've never seen a 377 powered anything run less than 10s low at the strip on the motor. I'd take a 377 over a 406 or 383 anyday. BIG BORE, SMALL STROKE. big bore/small stroke motors will ALWAYS make more HP than a small bore motor even of comprable displacements. Fords 302 made more HP and torque than an LB9 and thats with heads that flow 140 cfm stock!!! The fact that it's destroked lets it rev higher rpms easier to make even more high end HP. it's torque WILL NOT SUFFER, it's a bloody 377 cubic inch motor wth the same stroke as a 350. it will make just as much if not more torque than a 350 and a 350 has never been shy on torque. When you say comprable builds, the ONLY thing you can compare is dollars spent. Using the same parts in two different motors as point of comparison is absolutely idiotic. If we did that, then a TPI 383 with stock L98 parts would only be a few tenths faster than a TPI 350. With parts matched 600 HP 600 ft. lbs is very easy out of a pump gas 377. you'll have to use it in a car 3500 lbs or lighter though, so if you want to use a large car, then go big inch.

Dustin Mustangs

iTrader: (1)

Good Point Black. That's something that I failed to throw in my earlier rant. I would imagine this is mostly due to the shorter distance the air has to travel down to fill up the cylinder. This would lead to a higher VE and therfore more power! Sweet!

25THRSS

how about a big bore big stroke Better than a big bore small stroke.

BlackcamaroIROC

nope. if you're gonna increase the stroke size, you'll have to increase the bore significantly more for the same effect on top end. sure it'll be more "streetable" whatever that means. the only thing a 434 or 427 SBC does is let you brag about how big your motor is and wow a bunch of kiddies. sure it'd be quick and do nice smoky burnouts but it won't win races like a 377 will. You can bench race all you want, there are NO slow 377 powered vehicles anywhere and a 377 is a very popular motor for all forms of racing, drag, circle, and so on. it can sustain high RPMs much better than a big stroke motor.

25THRSS

wow

CrazyHawaiian

I'm definately no motor building guru, but heres how I see it. If you want torque then go with the 383. If you want top end horsepower then go with the 377. I've always liked big bore small stroke engines, so the 377 would be my choice. Just something about a SBC, when it revs past 7 grand I get all excited. But hey thats just me hehe! Alot of things should play into how you make your choice. What type of racing will you be doing, how much power will you make, and how much do you have to spend? Cost is usually the #1 factor that changes someones decesions to build something. Like for my example here, I would prefer to build a 377 and rev to the moon on boost, but unsure if I can afford to do it. I already have a 350 so the 383 would be cheaper. Tough choice. I think I'm gonna keep looking for a 400 block hehe.

BlackcamaroIROC

377s are no slouches on torque themselves. I'd take a 100 ft. lb knock on peak torque and save my tires for 200 HP up top
strong midrange and explosive top end is what drag racing is all about.

VashtheStampede

____________________________________________________
Now, as far as the original post and, for that matter, poster; Vash, what are you looking for out of this motor (ie. how much target HP, TQ and what RPM do you want it to happen at)?
____________________________________________________

I'm kinda young so I'm still trying to learn all I can about cars and engines. My dad helps me out a lot, but I'd like some other opinions too. I couldn't tell you exactly how much hp, tq, and rpms I'm looking to get out of whatever engine I get, but I kinda know what i plan to use it for. I plan on using it for street racing, but mostly I'm going to use it for mountain pass racing. I know a camaro is not the best chose for that kind of racing, but its all I have rite now. And since I plan on using it for that, the engine is probably going to need to put out around 300 hp and 300+ tq at fairly high rpms. It needs to be streetable obviously, consistant and fairly good gas economy. Plus it has to pass emissions. I don't know as much as I'd like to think I do, but thats why you guys are here, to teach me. So let the opinions and advice flow...

cammy

a bigger cubic inch motor will not alweys make more torq for example take a 350 put what ever kind of heads on it you want then take all the same parts off and put it on a 327 it will have a power at a higher rpm but if you think about it where dose the meaning horse power come from o ya that's right

It's a math equasion how you get horse power is mesered by engine torq and rpm i dont know the equasion off hand but if you dont beleave me think of it

ferririe has v-12's and v-10's what's the size of those motors less than 400 and a real short stroke shorter stroke means more fule will be neaded to make torq but will make more HP so anny who im rambling bye for now

ditchbangr

iTrader: (1)

BlackCamaroIroc, just looking for your opinion. In the october 2000 chevy high performance rag they dyno'd a 383 and a 377 with TFS heads and near identical supporting parts. The 383 ate the 377's lunch below 5k but above 6K the 377 put out more power - typically 15hp. Now I agree on midrange and top end pull like you stated. But get the power to the ground and a low revving(63-6500max) 383 or better yet 400 will probably put enough distance between it for the 377 to make up on the big end. Any ideas? I am going over to a guys house tomorrow who has a few 350 4 bolt blocks and 1 400 2 bolt block and trying to decide what to get.

bubba377

i don't know about u guys but here is my experance I am running a 377 with a turbo 350 stock rear with 3:73 gears pretty much stock suspention and i am running 11:68 in the 1/4 @120 mph with my set up but a 377 is no good right u figure it out !!!!

25THRSS

I have a good friend with a 406 in his 92 rs and he runs an 11.2 off the bottle at over 122 mph. That doesnt prove much though, as your setups are probably much different. Noboby is saying a 377 is a bad engine, just that it's stupid to purposely destroke a 400 block. Purposely losing cubic inches goes against all common sense and logic. 11.6 is fast, but i'm sure you would be even faster if you had saved your money and kept the extra 23 cubic inches.

MarkB

are you 12 years old? or do you just not have any education at all?

damn,reading that mumbled garbage gave me a headache.

VashtheStampede

if its not logical to destroke a 400 then why do people do it? there must be some advantage.

25THRSS

To meet certain class rules for displacement. Also, some do it because they are misinformed and think they will actually make more power.

TA

iTrader: (1)

Advantages and disadvantages to long stroke/short stroke

Pretty much covered here, with a few exceptions

Long stroke motor
Torque peak lower in RPM band
Can use a more conservative cam to produce good power and decent mileage (lower RPM range)
Does not require trick converters
You can botch your launches, and the motor will forgive you
harder on rotating parts and rings/pistons because of increased rod angles and piston speed

Short stroke motor
wants to be spun, torque peak higher
Will produce superior power, given the same CID as the long stroke motor and being tuned to take advantage of the extra RPMs.
Needs less ignition advance, as the piston "dwells" at tdc longer, and gets a more complete burn.
Requires a more aggressive cam and combo to work correctly
Will not launch as easily, however having a taste less torque at launch and packing the power up the rpm band when the tires are hooked is often an advantage.

...just my 2cents

Troy
So Cal

Battery

Also a 377 could be used for higher RPM availability to make up for the power loss in cubes. I know its already been said. But there are Honda's out there smoking v8s, and they dont do it between 1-3k rpms

It would be cool to be able to have the same VE on a 377 and 400, same equally flowing heads and back to back testing. See how many RPMs it takes for the 377 to equal an average HP/Torque rating, although torque, might be hard hehe.

25THRSS

right, but why purposely put yourself at a disadvantage to begin with. If you just kept the 400's stroke you wouldn't have anything to "make up." to begin with.

25THRSS

right, but why purposely put yourself at a disadvantage to begin with. If you just kept the 400's stroke you wouldn't have anything to "make up" to begin with.

Confuzed1

iTrader: (4)

OK - since I spent the time to read this thread, I'll give ya my 2 cents. In general, streetable and high revving don't go together IMO. Not to mention it will cost more to build. And emission compliant too??

You're most likely better off with a power adder so you have at least a shot at passing a sniffer.