SlowMaro

i dunno why people dont do it then, ill stick with my camaro, it looks better, runs better, faster, and is just over all better --other than my mysterious backfire problem lmao---

txhotRS

No offense to ANYONE... but In my experience... a big number of guys WITH mustangs that I have raced... HAVE LIED ABOUT WHAT THEY HAVE... they say... "heads, cam, exhaust" only to cover up that they are stock with a bottle (because WE ALL KNOW, when a guy uses a bottle, instead of MOTOR MODS... let's not go there)... or say... "yeah, I got all this stuff" and WITHIN 50 yards I'm 2 car lengths ahead..

Dewey316

typicaly a short stroke, large bore has a higher powerband, and less tq down low, where as a long stroke, small bore has good torque, but putters out up high. i am not sure how you came to the conclusion you did, maybe you typed it in wrong.

txhotRS

BIGGER BORE = HIGHER TORQUE... SHORTER STROKE = HIGHER REVVING ENGINE... a 5.0 has BOTH... so the RPM's rise FAST which = quicker shifting, WHICH = changing gear ratios WHICH = getting up to speed FASTER which = LOW-END POWER

Dewey316

changing gears does not equite to the engine making more torque, it equates to mechanical advantage. a 383 will make MORE tq than a 302 any day, no way around it, gearing is a whole nother issue, but not directly realated to the torque the engine makes.

txhotRS

think about SMALL BORE ENGINES... european sports cars... OK, ... they can top out at 160 MPH + what is the last BIG BLOCK CHEVY that you saw with a speed over 140 MPH (drag cars DON't COUNT)

Dewey316

well yes, most big block don't go above 140 because of the cars they are in. i am not going to take a 50's shoebox about 160, regarless of power. and typicly the have very steep rear gears, and a highest tranny gear of 1:1 you just plane run out of gear.

also top speed is not limited to the bore of an engine, it has everythign to do with power:weight, and with the area dynamics.

txhotRS

I never said that short stroke engines DIDN'T have upper end... I said the majority of their power band is lower. WHILE the majority of the powerband of a camaro (longer stroke) is mid-upper end...
Have you ever looked at the torque/hp curve of a long stroked engine... they are ALMOST the same... Meanwhile.. the torque/hp curve of a short-stroked engine the torque curve is WAY higher than the HP curve

MarkB

bore = hp....stroke = torque

this is why people build 383s and the like,longer stroker = more torque. consequentally.. a DESTROKED 400,likewise a 377 will make more upper RPM power..with less bottom end tq.

rear gear ratios mean nothing to what a motor makes...its mechanical advantage. granted running 2.73 gears with a huge cammed small inch or large inch engine doesnt help any..

theres a saying in the autmotive world...torque is how hard you hit the wall,horespower is how fast you hit

txhotRS

short stroke motors HAVE A LARGER RPM range... not powerband...

Dan W

LOL, I know what you mean... never trust a mustang guy on what he says he has... it can go both ways too... I know a guy who claims to have a bone stock motor but I know for a fact he has at least a stroker kit, ported heads and aftermarket cam... guy runs real low 13's.

txhotrs, no offence taken... I like both GM and ford stuff for different reasons... those fox body mustangs are a great bang for the buck car but I like the f-body better. Better looking, better handling, better ride, better aerodynamics. I had someone (non motor head) once ask me if my mustang GT was a ford escort... I think that about sums up how I feel about the mustangs looks.

Dewey316

yes i have, and that is why my one friends 305 has its peak torque at 2500 RPM, while my other friends 327 has his peak torque well above 4k. both cars had fairly similar cams, and both carbed. so the comparision is pretty close.

305 = large bore:stroke ratio
327 = small bore:stroke ratio

txhotRS

That's not what I'm saying.... I MEAN the Torque - to - HP ratio... for a specific vehicle... if you have a 383.. for example say it has 400 HP/405 Ft-Lbs of torque... the numbers are VERY CLOSE while a short stroke WITH THE SAME BORE would be around 350 HP/ and 430 Ft-Lbs of torque.. there is a difference in the curves of this motor
I agree with you on the actual INDIVIDUAL torque curve... that's correct

MarkB

bullchit. plain and simple bullchit..a shorter stroke motor wouldnt make more...how the hell is that possible? you need to stop reading honda magazines man. your bantering is getting on my nerves.

simply put a small bore/large stroke engine will produce MORE bottom end power with a reduction in upper rpm power

a large bore/small stroke motor will make less power down low..and MORE power on the top end

txhotRS

WHAT I'm trying to say.. is that with a short stroke engine there is a LARGE RPM band... but the torque curve is ALL DOWN LOW (under 4000 RPMs) after the initial get-up-and-go... (torque) the upper-end (HP) has to keep you there.....
On a camaro, however, there is a SMALLER RPM band(unless it's stroked)... (usually only up to about 5700-6200 RPM) and the torque curve is slightly more MID-RANGE--- more equal to the HP curve

MarkB

uhh once again..no

a short stroke motor will have a HIGHER tq curve...where as a long stroke motor will have a lower one.

and you tell me...what kinda camamro motor runs to 5700-6200 stock? every v8 in all the 3rd gens falls flat on its face after 5k.

you need to seriously think before you type.

txhotRS

Do you UNDERSTAND what torque is....
It's the ability to move a [1 foot bar that weighs 1 lb.] one foot around an outer edge from a powersouce on a central pivot... TAKE a 1 foot bar that weighs 1 lb... grab it on one end .... keep your hand in the same place... and ROTATE the other end 1 foot, with your hand as the pivot.... THAT IS 1 Ft-LB of torque... If you have a shorter stroke, the crank WILL spin quicker , correct ?, THEREFORE MORE TORQUE BECAUSE IT SPINS AT HIGHER RPMs

txhotRS

1.. who said my camaro was stock... 2... I think we are trying to say the same thing.... I mean higher torque curve relative to the amount of power... not in relation to the RPMs

txhotRS

SHORT STROKE = higher torque at lower RPMs... that's all... I'm not trying to get under anybodys skin.. but there are a few things you learn in a mechanical engineering physics class

txhotRS

Formula305.... all I'm saying is that mustangs feel balsy because of torque... but without MODS...to keep the HP up, they can't keep up with a moderately fixed-up camaro ...
Good Luck

MarkB

uhm. you sir are a dumbass.

short stroke = higher tq @ HIGHER rpms
long stroke = higher tq@ LOWEr rpms


example...if you build a 302,and a 383 exactly the same,only difference being the strokes, {granted a 383 is 4.030 and 302 is 4.000} the 383 would win in a equal car situation.

the 383 is going to be the red light to redlight stump pulling car,the 302 is going to be the freeway flyer.

Dewey316

you have it entirely backwards.

you need to go back to your physics teacher and take the lesson over.

if you want the whole scoop look at the equations

TQ = Force * Distance

in an engine, distance is the stoke, the tq goes up as the distance increasses, it is simple math. you can't compete with the laws of physics, it is a losing battle.

you comparisons of the 5.0 ford vs 305/350 chevy are apples to oranges, look at some real solid numbers like a 327 vs 383. same engine, same bore, only diffrence is stoke. the 383 will ALWAYS make more TQ period, basic physics. the 327 will have a higher RPM potential, and since HP = tq * RPM / 5252 as the RPMs increas with the 327 the HP increases, the point that the 327 makes more HP than the 383 is when the rpms get to a point wher the 383 is either incapable of spining, or has the 383's torque output has droped well below its peak.

MarkB

hahah my *** man.

yeah i raced my friends 12.3 12.4 second mustang on saturday...in fact i blew up my 350 while doing so..we did a few runs..and video taped it for my website....amazing thing is...

since you claim mustangs have so much bottom end TQ,,,why did a roughly 13 second transam...jump a 12 second mustang off the line i had him a car length,but as soon as we got to the top of 1st...he went fishing with me.

top of 3rd gear he had put about 5-6 car lengths on me at 130mph

he has a built 302..with a heavily built wc t-5,both of us were running all motor.

from a roll of 10-15 mph...i can always jump him a half car or car length... anything else and its a game of fishing and he just reels me in.

explain that one.

Dewey316

one last thing, and this is it, we shouldn't even have to have this silly debate.

from www.howstuffworks.com


Let's start by answering the question and then look at why the world works that way.
The answer to your question has to do with the way the two engines are designed. Your 11 liter diesel engine has a long stroke. That means that the piston is traveling a relatively long distance up and down in its cylinder on each cycle. A racing engine, on the other hand, has a short stroke. The piston in a racing engine has a large diameter for the engine size, and it goes up and down a relatively short distance on each cycle. This means that a race car engine can run much faster -- up to 15,000 RPM in a Champ Car engine -- but has relatively little torque. A large diesel engine usually cannot get above 2,000 RPM, but has huge torque because of the long stroke. The torque is what lets your engine pull a huge load up a hill.

...

What an engine naturally produces, however, is torque. Think about one piston in a gasoline engine. When the gasoline ignites, it pushes on the piston, and the piston exerts pressure on the crankshaft, causing it to turn. The crankshaft feels some number of foot-pounds of torque in the process. There are three variables that affect torque:

The size of the piston face
The amount of pressure that the ignited fuel applies to the face of the piston
The distance the piston travels on each stroke (therefore the diameter of the crankshaft). The bigger the diameter of the crankshaft, the bigger the lever arm and therefore the more torque.




there, that is not me saying it, that is not me arguing, that is purely and simply the physics behind and engine.

Beast5spdGTA

This is completely wrong.

Torque is a moment (force x distance) acting on a point/pivot/whatever. 1 ft-lb of torque is equal to a 1 lb force acting at a 90* angle 1 foot away from the point of measurement. (someone correct me if that's unclear)

Example: Take a 1/2" drive ratchet(roughly 12" long) and put it on a bolt. The force you apply to the end of the wrench is torque. If you apply 100 lbs of force on the end of the 12" long wrench it's equal to 100ft-lb of torque acting on the bolt. The bolt hasn't moved at all.

The measurement of torque has nothing to do with the distance something turns or moves. There is a relation between torque and time. I think it's call Horsepower. 1 HP = (550 ft-lb)/(1sec)

HP = (torque x rpm)/5252

I see I was a little slow in posting. thanks Dewey316

Dewey316

no problem, it is really hard to argue with the math. physical laws, are physical laws. and the wonderus ford 302 cannot beat those laws of physics no matter how much he thinks it can.

brodyscamaro

This is a stupid stereotype. Oh well, this thread is going to be locked anyways.

JesasaurusRex

iTrader: (3)

Jesus im confused

Black363IROCZ

it doesn't a 5.0 weighs a much as a little honda! they are light, not powerful, keep that in mind. Strip weight out of your car, tubular K-member, port the heads (do it your self or have a friend help you), LT1 cam, ultimate TBI, and 3.73 posi. your car will weigh less and make equal power, providing he's stock. if not, spray the **** out of that 305 and keep the money left over for buying a new motor, like a CHEVY 302, then show his *** what's up with a 302 done right.

TBIfly

my head hurts....all this math and physics is making my head spin.

So will a moderator please rename this post "What is torque, and how does it apply to a $1000 budget build"

The moral of the story is this:

Get those gears, get that cam, get that intake, open air, chip, and injectors..

::steps down off soapbox::

-blain



P.S. SlowMaro...when you refer to your sig, please include your sig.

vwdave

All I can say is Wow.......

seanof30306

iTrader: (4)

good *** .... this poor kid just wanted to know how to beat a mustang for a grand!

let's get back on point.

rule #1: better breathing (in/out) = more power. he already has the exhaust and breather covered. the next thing to do is make the tbi unit itself breathe better with ultimate tbi mods. i sure wish someone would add to the tech article concerning this with pics, by the way. that way, if he can't do it himself, he can take it to a mchine shop and get it done.

the next choke point in breathing is the intake. going back to the controversial "f-notes" project in hot rod where they got an 89 camaro 305 into the high 13s, the performer tbi is not the hot setup. i actually spoke to the former owner of traco engineering (the shop that did the work) who said the carb intake with an adapter flowed much better.

the next choke point is the heads, but with a budget of a grand, there's nothing to be done about that.

rule #1: if it don't hook up, you're screwed. a posi and a gear swap will be critical to whupping that mustang. i disagree on the 373s, though. the admittedly sucky powerband of the 305 makes most of it's torque at lower rpms. going back to f-notes, the biggest problem they had after getting to 300hp was wheelspin due to the torque curve. while he's nowhere near 300 hp and won't get there for a grand, i still think the 3.42 is a better choice. i once had a car with a high-torque setup, swapped from 3.31s to 3.73s and slowed down.

rule #1: it's the tune, man. the smartest thing he can do is add a vacuum adjustable fuel pressure regulator after swapping intakes, find a set of 350 and cop car injectors on ebay, then get the car dyno-tuned with a wide-band 02 sensor, settling on which injectors, fuel pressure and initial timing settings work best. these tbi cars are incredibly sensitive to tuning and that's the best way to get it right. also, he might not need to burn a chip at this point, as fuel pressure and base timing adjustment could get his air/fuel ratio right in line.

rule #1 less is more. they're doing a 305 tpi firebird project in gm high tech performance. i don't have the magazine in front of me, but i believe he picked up 17 hp with a set of underdrive pulleys. i never realized they offered that much of an increase. i'd look into it.

rule #1: if it don't chop at stoplights, chicks will ignore you. he may come back from the dyno tune feeling like he's not making enough hp. even without swapping the heads, he should be able to make some serious power with a cam (and valvesprings) that'll let him rev a little higher. i'd recommend against an lt1 cam, etc., simply because those cams are designed for specific applications. get on the phone with a reputable cam manufacturer, accurately describe your setup and goals and let them make a recommendation.

i'd do all of this before i went into major things like swapping heads, converters, etc. one of the biggest mistakes i see people making with their cars is not maximizing what they have through tuning and experimentation before they go bolting more things on.

the smartest way to go about any project is to make one change, dial it in, evaluate it on the dyno, at the track or both, then change another. he has till july, a little patience on his part just might make his pal in the mustang pretty unhappy.

SlowMaro

my sig is gay , i swear, half the time it shows up, the other, its missing in action, ..sorry bout that though.....it usually shows up automaticly....my sig is like my car itself, ...randomly breaks and fixes itself with no warning, or cause.

SlowMaro

ps, i wish someone would post pics of the tbi mods as well, i dont quite understand what all im supposed to *grind down* i dont want to have at it with a dremel and at the end go ...uh ...oops...


lol dont say "dont get an lt1 cam" i put one in mine, i dont want to feel like i wasted my time and money....i saw a decent increase of power out of the cam alone, no intake, no nothing, just a lt1 cam...oh well.....i heard from 20 different people to get an lt1 can so i got one...

JesasaurusRex

iTrader: (3)

I agree with Slowmaro, LT1 cam is that "way" to go, since rollers are hella expensive to begin with an LT1 cam is a great replacement for a stock TBI cam (anybody know specs on stock cam think it would be good for a laugh) as for the "way" part I just said that because I ordered a zz4 cam just because the LT1 cam didnt have enough lift for what I was lookin 4. Any roller from a higher performance engine is good tho.

txhotRS

specs on a STOCK LT1 cam are as follows
93 LT1 202/207 duration @.05 .450/.450 lift w/ 1.5 rockers, Lobe seperation of 117
94-95 LT1 203/208 duration @.05 .450/.460 lift with 1.5 rocker Lobe seperation of 116
96-97 LT1 205/207 duration @.05 .447/.459 lift with 1.5 rockers, lobe seperation of 117...
Keep in mind this is the cam spec from a Z-28 / TA LT1 only...

JesasaurusRex

iTrader: (3)

Thx but i meant TBI cam

Beast5spdGTA

TBI/peanut cam specs p/n 10088155* lift int/exh .350" .384" duration int/exh. 179 194 lobe sep. 109.0

Thirdgen cam specs can be seen in the "Tech Data" section on the main page of thirdgen.org

SlowMaro, there is a box under the "options" section when you type a post that you have to check off to have your sig. appear, it only automatically shows up when you start a topic.

JesasaurusRex

iTrader: (3)

Jesus that lifts horrible, same goes with duration, thank *** i ordered my zz4 cam, L31 Heads and Performer RPM AirGap intake in the next 2 weeks w00t :lala:

JesasaurusRex

iTrader: (3)

um...why do they edit out G O D

seanof30306

iTrader: (4)

i don't mean to take shots at anyone for the cams they choose. the point i want to make is, if you're going to go to the trouble and expense of changing a cam, it makes more sense to get one dialed in for your specific application. cam technology has exploded in the past 20 years. slight differences in lift and duration can make big differences in performance.

looking at the specs on the lti cam, isn't the lobe separation too great? i thought tbi performed best on a 109-110 degree center.

JesasaurusRex

iTrader: (3)

I agree, but an LT1 cam is like 50 bux, aint the greatest cam but a brand new one is like 250 so thats a 500 percent increase in price, is it anywhere near a 500 percent increase in performance? I didnt know the Lobe seperation was so great on an LT1, dont really care tho cuz i got a zz4 cam. Was 150 all together with shipping, 100 bux cheaper than a new roller but 300 times more than an LT1, really doubt itll be 3 times better but i decided it was worth it. Its all in perspective, how much do you want 2 pay for how much power. LT1 cam is probably the best cam for the money, mines is better but not 4 the money. You all understand its all preferance.

txhotRS

HEY HEY HEY, I might have been wrong about the low-end torque bull sh it.. SORRY GUYS. ,BUT not on this... I've lost too much money... A TBI is computer controlled... WHICH means MAP sensor, and vacuum pressure for use of the injectors. 109-110 lobe-seperation WILL KILL computer vacuum.. and the car won't run well, IF AT ALL.. the computer NEEDS at least 112 lobe seperation, if not more... It runs better at about 114-115.. plus, WHEN YOU USE IT FOR A 305, the RPM range is increased because of smaller displacement, With a decent set of heads/headers and the LT1 cam, and an injector-TBI upgrade, the 305 will out-preform a stock LT1.. WITHOUT the heads (for a budget car) It'll still be up there
ALSO ... .. YEAH SURE, I called the chevy dealer a few days ago... $369.95 for a STOCK 95 LT1 cam from a Z-28, WHO'S GONNA PAY THAT , STICK with E-bay.. $41.50 for mine w/ 50k on it

Dan W

This should go without saying but the amount of manifold vacuum is also dependant on duration and the longer duration you have the more lobe sep you need to keep your manifold vacuum up. As you run bigger cams and cams with less lobe seperation you will require more E-Prom tuning to get them to idle and drive nice. Less lobe seperation will make substantially more low end torque at the cost of more difficult tuning. Keep manifold vacuum at idle above 11" vacuum for adequate tuning resolution and be aware that a speed density car that idles at 11" of vacuum needs lots of tuning to get right.


The LT1 cam upgrade is an attractive option for most but he is not going to reach his power requirement with it. Heck, the LT1 only made something like 285 hp with it with a better flowing intake / head combo.
I think the previous poster who said you can buy roller cams for about $250 was refering to Aftemarket cams, not new GM units. A quick check in your summit catalog will show this to be true.

Formula305FI

LoL wow i Just needed a little help not an entire pys. class going on. Haha I pay my college to teach me that. Just some basic tips...

vwdave

Are the guys who are selling the LT1 cam have only 1 arm? If so, the other arm is behind his back with a bottle of KY Jelly because that is rape.

I paid only $175 from SDPC for a new LT4 cam.

SlowMaro

i got my lt1 cam for like 40 bucks shipped, ...didnt think it was a bad deal......40 vrs 250 ..my stock heads cant handle much more than .450 lift anyways....

txhotRS

no guys... the $369 is from the DEALER.. you know,, the same place that charges $35 for a serpentine belt... I paid $39.50 for mine, I'm not THAT stupid

JesasaurusRex

iTrader: (3)

Thank You

SlowMaro

lol i thought he ment he paid 40 bucks for the belt...