TheViper

i have a few questions.

with the setup below my 283 feels more like a 305 than a 283. it has good off idle trq but seems to fall on its face at about 3000 or less.

i'm wondering if it is the stock manifolds, cam, or intake.

it still has the CC distributor with a new edelbrock 600cfm carb.(when your 15 you don't have much money to get stuff you need) it has a little 2"x10" open element air fiter, i'l be getting a 3"x14" as soon as i can get some money along with a vacume advance distributer(only $20 left).

what do you think is the biggest problem that is causing it to crap out so early?

if you need any more info let me know.

RB83L69

exhaust and distributor

Throw every single piece of anything that's compatible with LG4 in the trash, and put a chassis-specific exhaust for some other car on it, such as a L69 or TPI 350; that means headers, Y-pipe, cat, & cat-back.

Your distributor, without the computer, is staying at staic timing at all times. No advance whatsoever, ever. You need about 30° more than whatever you're getting at all RPMs above 2500 or so.

Leave the carb, intake & cam alone until you fix those overwhelming malfunctions. No amount of playing with anything else will overcome them.

TheViper

it has a flowmaster catback, but its not doing any good with the stock manifolds and catback. how much hp increase do you think it will have once i get a y-pipe made for my headers?

i was told by a guuy who helped me with this that it should have about 300-325hp with headers and all. right now it feels like 200-225. do you think with these changes it will get up to 300, maybe 275?

darbleinad

i would worry about getting a proper, non-computerized distributor first, then getting headers, a high flow y-pipe, and a high flow cat (if you have to have one). there is no question the exhuast is choking you huge, but that computerized distributor is really hurting you. you wont see the full benefit of anny of your mods or future mods until you get a regular HEI distributor. good luck with the project.

88 350 tpi formula

iTrader: (9)

the 283 still has a small bore "like not the same" as 305 but, still has a hard time flowing. the 302 has the same stroke but, at least has a 4" bore

88 350 tpi formula

iTrader: (9)

should be close to 275hp at fly wheel with it well tuned

five7kid

iTrader: (14)

Yes, yes, yes. The ol' "CC/non-CC mix & match".

Don't.

There is a little advance in the distributor (at least mine will when the 4-wire is disconnected), but not nearly enough.

And, you did yourself no favors by putting a non-CC carb on it. The CC carb was more than capable of providing for your needs (assuming all of the supporting cast is intact and functioning), and you just took a step backwards. Oh, well, either continue on your current course, or put it back together and try to get your money back out of the non-CC carb.

That isn't enough cam to be talking about approaching 1HP/CID. At any rate, you're going to need the exhaust work to get much above 200.

TheViper

i'm sure it will easily have 250-275 at the rear wheels with the current cam, its only about 25-50 more hp.

i'm going to stick with the non cc carb. i'm very happy with it, all i need is a $30 distributer and i'l be fine.

zippy

the distributor is a big problem there, i agree. i'd take a 305 over a 283 anyday. with them parts, i'd be willing to put money on you not makng over 220rwhp.

five7kid

iTrader: (14)

And I'm sure you're wrong. Perhaps 250-275 gross at the flywheel, and 50-75 less at the wheels.

zippy

i think that's even a bit high gross, but anythings possible.

TheViper

well, its pretty close to my brothers lt1 camaro with 300hp.
i know by the time i'm done with a few more things that it'l keep up with it.

raggedout91RS

Your 283 should have your estimated HP. 041's are pretty good flowing heads. I have a set myself on a 355. If I were to make a guess I would say you had 250 at wheels if you had a decent cam like an XE 268 and everything was tuned. I'm sure someone will disagree with this though. I have tried mixing CC componets w/ nonCC and it doesnt work too well. Good Luck.

TheViper

i've talked to a lot of ppl around here who build race cars, race and are mechanics. they all say it'l have at least 300-350. i belive it will have about 275-325 at the rear wheels when i'm done with it(cam, intake, headers). i'l eventualy get a 350 and it should have about 350-400 easy with the 041s and 10.5:1 comp, and a good cam. the 041s are about the same as vortecs. they are probably one of the best probuction heads of there time. everywhere i see them mentioned like on mortec they say they are good performace heads.

F-BIRD'88

The 041's are one of the good heads, but in stock form are not even close to a vortec head. The vortecs flow about 228 cfm out
of the box. the 041's are about 200/205 stock. the vortec exhaust port is better too.
BUT,,, that's not to say the 041's cannot be improved with carfull porting, they can. Thats why they are considered good heads.
Your motor with stock 041's will make about 275/300 gross hp.
***WITH headers and freeflowing exhaust***
Stock manifolds will resrict this motor to about 200 hp.

If you want 350/400 gross horsepower you'll need to speed up the lil 283 with full ported heads and bigger cam, a better intake manifold , headers etc.
This will raise the power band (rpm range) quite a bit.

You'll then need a much higher stall converter for an auto and a high rear gear ratio to make use of the higher powerband.
If ya want to go this high rpm power route don't be shy in selecting a rear gear.
more gear is better on a 283.
The difference in buiding a 283 as compared to a 350 with the same cylinder head flow, (horsepower potential) is the 283 will need to rev much higher to use the airflow. This is why a higher converter/ cam , rear gear is nessessary.

A converter that is normally rated for a certain stall on a 350 will have quite a lower actual stall on a 283 (less torque)
Ya have to take this into consideration when picking a converter for a 283.

RB83L69

If you want to know how much HP you really have, go take it to the dyno. We can all tell you what we think based on our years of experience, and you can tell us all day long what you think based on what you wish for, and neither one will really have any effect whatsoever on how much power the engine actually produces. Go measure it. Maybe you'll get a feeling of great personal satisfaction, maybe it'll be a bitter disappointment; but at least it will be reality, and will give you a baseline for before & after comparison.

A bunch of us who have been doing this sort of thing, some of us professionally, and some of us for more than twice as long as you've been on this planet, have tried to tell you the truth based on what we've experienced over and over again. I don't get the feeling that we're communicating very well, somehow. It's hard to tell someone without experience what the value of experience is, sometimes; everybody wants to think that they're unique, and plowing new ground, and the first ones to think of something. Let me tell you, a 283 with double-hump heads isn't new or unique, I had one just about like that in the 70s (mine was a 292 with a big solid cam in it) except in front of a 4-speed where it belonged. Believe it or not, I know exactly what one runs like and why, BTDT.

Avoid things like the air cleaner mod you were talking about. It won't do one lick of good, as far as making your car faster, it's money down the drain. If there is any one piece of advice I can give to a starting-out hot-rodder, it would be this: Analyze the car's (note that I said "car", not "motor") performance honestly and unemotionally and without preconceived notions of what you expect to find, and be prepared to accept the truth, whatever it is; then determine what the "weakest link" in the system is, that is, the one thing that most seriously restricts the car's performance; then select a suitable replacement. More often than not, you'll find that the thing that's limiting the car's performance, is something you can't see (cam, heads, compression as it is in your case, converter, gears, rear suspension, etc.); and at least half the time, it will be something that's not in the engine compartment. Above all, resist the temptation to un-bolt and re-bolt big shiny expensive chrome things that sit right on top of the motor, just because everybody sees them whenever you open your hood. You've already done a bunch of what I would consider to be exactly that such as the Edlebrock carb {insert $375 worth of gagging sounds here}, and look where it has gotten you so far.

You're right about 041s, and other of the later double-humps such as 186 and especially 292; they were the best of their time. That time was long ago, and we've all learned a thing or 2 since then. Why, even GM has learned a couple of things, and actually managed to put some of them into effect without butchering them the way they did roller cams. Vortec heads are one of them. When you have gotten all you can get out of those 041s, and you're reasy to step up for your next dose of sobering reality, put a set of Vortecs on your motor, and take it to the dyno again. You'll see immediately why people are using them for budget build-ups.

Go get your car measured, and come back and post the results. Don't be ashamed or boastful or get all bowed up at us about disagreeing with your fantasy, just do what people who want their car to run better do, and become a better car builder as a result.

88 350 tpi formula

iTrader: (9)

screw my 400 I guess the 283 is the ticket... you can make tons of hp with mismatched stuff

TheViper

well, maybe i'm wrong. i was just hoping for about 300, because thats what everyone told me when i was starting it. i guess the best thing to do is like rb83l69 said and take it to the dyno. fighting about how much it'l have wont change anything. sorry if i got anyone ticked off but i was just hoping for 300 so much. i might be getting some money soon and i'l probably drop in a 350 and build that up.

SSC

Well the 283 isnt a bad running engine (just reading this post now) the modifications you have made are probably going to be close to 250 crank hp. My sister in laws brother built what he thought was a killer 283 for his 64 Impala (wanted an original engine) and it turned out to be a big dissapointment on the dyno, two days latter he had a "stock" 85 Camaro 305 that I had given him back in. Now is you were to pop those heads on a 350 with that cam you would have a nice engine but I doubt 300hp at the wheels still.

zippy

well, let us know when you dyno it, still willing to put money on the dyno numbers.

pontiacZ28

This is the point where I wonder if this post is a joke. No offense but in the end you probably won't be beating new V6 camaros which are at about 220hp, let alone hanging with a LT1.

TheViper

seriously, its not that far off the lt1. its got about a little over 225 at the wheels right now. where the lt1 kinda dosn't pick up after 4000 the 283 keeps pulling harder and harder as the rpms go up even with the current cam and manifolds. it wouldn't have a chance against it in a race but it isn't that far off. i just want to see what it'l do with the headers on. i need to get rid of the crappy 1.5" log manifolds. it will have about 250-275 at the wheels once i get the headers on and a new cam in. not what i expected but it'l be ok. the manifolds i have on it right now are the bigest problem.

these heads have been worked on. i know they have been milled .035 and have 2.02 valves. i'm not sure if they've been ported though.

there must be some reason somebody who builds 283 and 327s for circle track for a living would say he'd be surprized if it didn't make 350. and 4 other people who are mechanics and race car builders saying it will have about 300-325

zippy

seems to be some odd defending of a slow car. at the beginning you say it don't want to pull over 3000 of course this is because your not getting the timing advance it should have. then you say your close to your brothers lt1 camaro with an estimated i assume 300hp. now your saying it pulls higher than the lt1 even with the restrictions it has yet won't pull over 3000 at the beginning of this post. odd huh. (btw, the 3.8 camaro is 200hp).

btw, you said the LT1 kinda doesn't pick up after 4000, you may want to fix it then since no LT1's fall off at 4k in normal tune and don't really fall off much until just before the rev limiter at 6k.

TheViper

i got a new distributer a few days ago. it works now.

zippy

a few days ago, on the 13th to be exact you said all you need is a 30 dollar distrubutor?

TheViper

i got it 2 days ago to be exact. and a vacume advance from the junk yard works fine, maybe not perfect but it works.

bradkeith

Good to hear you got it running

novadude

Who the hell uses 327's and 283's for circle track these days?

Am I in a 1969 time warp?

There is no way that 283 is making 300+ at the flywheel. I have owned and worked on 283's and 327's, and I can tell you that there is really no magic in those old motors.

In fact, you'd be lucky to see 300 HP at the engine with 350 c.i. and that combination of parts. 283 definitely ain't gonna do it!

Just my opinion.

TheViper

well, the 302 made about 350 with those heads. it just had more cam, compression, and a few more cubes. i'm planning on getting a better cam soon. its got about 9.5:1 compression right now. right now its making about 200-225 at the wheels, so whats that at the crank, 50-75 more? thats with a small cam and 305 manifolds.

novadude

I seriously think 225 hp at the flywheel is more realistic (perhaps optimistic) with that cam and overall combo.

The 302 was 290 hp with stock manifolds. It was not 350 hp as delivered. Now with open headers and 7200 rpm, 350 at the flywheel was possible, but it had a lot more cam and compression than your engine.

The 302 was a lousy street engine.

Not trying to rain on your parade, just telling like it is.

TheViper

right now it does have 200-225 at the wheels. the lg4s have about 150-160 right? my brother has had 2 lg4s and has a 97 z28 with an lt1. the 283 it about between the lg4 and an lt1. all i'm saying is that me, my brother, and my dad have driven it and we all agree that it has 200-225 at the wheels.

the z28 was way underrated at 290. the 302 with a manual tranny against a 375hp 396 with an automatic tranny won in the 1/4 mile by .5 seconds and 4 or 6 mph with a little slower 0-60 time.

RB83L69

OK, we've argued about it enough.

Post your dyno numbers, or a track time & weight. Let's cut the BS and bickering and get down to some reality.