Ok... i need some major help here... my dad and i have been woking on my car to build up my 305... i replaced the cam, put on a 650cfm Edelbrock Carb, Edelbrock Performer RPM intake, Hedman headers and Y-pipe, and other little things... but to my dismay, we finished putting on the headers and Y-pipe tonite nd I went to go for a ride, the Y-pipe has a cut-out so I was running the exhaust out of that... my car had been ungodly slow after we first installed the cam, carb, and intake so we thought all we needed was the exhaust to make the car go... so after a disappointing nite i would like some help, anyone with any help pleaz let me kno

 

need some information on the car.....

 

So what cam did you use? Did you set the timing with a light, and what did you set it at? What is it doing? Is it popping at all, is it stumbling or surging? Are you using a non-computerized distributor?

 

it's like calling your doctor and saying i don't feel good, what's wrong with me. we need much more info to make the magic wand work for him. has to at least warm it up.

 

Did you have someone check your carb while you floor the gas pedal to see if the blades open fully?

 

ok... sorry guys... i'll post more info tomorrow when i can ask my dad exact cam specs and what the timing is at... but for now we didnt use a timing light, theres not popping, and we took out the computer... the bottom line is there is NO rwhp, its jus not moving like we want it to... it was faster before when it was all stock w/ the TBI... pleaz post what u need to kno to help and i will let you know ASAP... thanx for your help

i dont remember checking the carb like that...

 

Did you reuse the stock distributor. If you did that is definitely your problem. The stock distributor is controlled by the computer which you took out.

You need to find a non CC controlled distributor!!

 

Cam Specs:
Advertised Duration: 272º
Duration @ .050: 216°
Lobe Separation: 110°
Gross Lift: .454''
RPM Range: 2000-5000

we used a Mallory Unilite Distributor, Ignition Coil, Blue max wires

timing is set at 0* TDC

 

Get a timing light or vacuum guage. set the initial timing to 10*-12* or with vacuum guage max vacuum then drop 2in. 2000+ RPM powerband wont have a lot of low end grunt without a stall even if you do have a manual trans it wont be impressive without a low numericly high gear ratio.

 

Why running 0* initial? and how much total?
Unilites usually come set with only 22* centrifugal advance. You can adjust this up a bit or down by moving the stops on the weights. I would normally run around 15* inital and 20* centrifugal.

 

post your full combo so we can judge it all...
Do you get a vibration at all?
Does the motor bog down when you try to accelerate?
give us a detailed description of EXACTLY what happens when you try to accelerate quickly...any funny noises, vibrations etc

 

Engine-
305ci

Cam-
Advertised Duration: 272º
Duration @ .050: 216°
Lobe Separation: 110°
Gross Lift: .454''
RPM Range: 2000-5000

Carb-
Edelbrock 650cfm

Intake-
Edelbrock Performer RPM

Exhaust-
Hedman Headers
Hedman Y-Pipe

Etc-
Push rods
Edelbrock Double Roller Timing Chain

The car makes no unusual noises, no vibrations, I just get no acceleration.

 

you have a 305 thats why its not fast! j/k umm combo sounds okay seems like you did something wrong when you set it up. lsa is a little bit low you could be having some vacuum issues with that??? someone else will chime in.

 

if your heads aint flowin the engine aint going to be fast. people are mistaken with how power is made. the BIGGEST improvement can be made in the heads. i belive the stock heads on the 305 suck.

 

let me guess you have the original rear end gears and stock stall converter right?

and now you put a huge cam (for a 305) and expect power from a dead stop? 272* of duration is more than i would run in most streetable 383's WITH gears and stall. way to much cam with that drivetrain...

 

How did you break in the cam? If you didn't do it right, and it still runs, either you got lucky and had enough assembly lube on it, or you wore it down and created a dog.

 

IMO the cam is borderline but you still should feel something come on after 3000 rpm at least. Sounds to me like your timing is set to retarded and isn't advancing enough to catch up.

What's it gonna hurt to loosen the one little bolt holding the distributor tight and advancing it 10 degrees. That's about a 5 minute operation. I used to do it on the side of the road going home from work fine tuning my new engine on the way home.

 

<b>but you still should feel something come on after 3000 rpm at least.</b>

Oh after 3000 rpms you say? why because the cam says so?

my friend if he is still using the stock 305 heads, which by comparison STOP flowing after 3000 rpms...

do you see my point NOW?

 

Is that cam a roller cam?? If not that could have something to do with it. If you still have the stock stall and 2.73s it will be slow. I still have the stock stall in my trans and I know its holding me back. Im getting ready for some 3.73 gears.

Sounds like you have put something together wrong...either that or its just slow...with stock swirl ports it isnt going to be fast...

 

It could be just as simple as a mismatch of parts... the parts you listed (especially the cam) need a relatively high compression ratio to work properly. That is probably the problem, along with the stock converter (~1600 rpm stall) and REALLY tall stock rear end gears. A cam like that will want 3.73 or 4.11 gears and probably a 3000 stall converter. Your car probably has 2.73 or 3.08 gears and 1600 stall.

 

Guys your just repeating exactly what i said already!!!!!! sheesh.

but it just goes to show you...

 

I am running non ported 305 heads on my 350 currently with a xr270hr cam, 218 degrees at .050 and .498 inch lift. I run a 14.8 at 98 mph. 98 mph ain't no speed demon, but it isn't what he is describing either. And mine pulls to 5500 rpm easy. And the crappy e.t. is due to the open diff.

 

And whats your rear gear / stall?
hows it feel off the line? his old 305 probably made bucket loads more torque than it does now, especially with the old TBI... all they HAD was torque. he is describing a LOSS in power, but has not run it at the track yet either. chances are, he is feeling his loss in low end torque, much the way my 500 horsepower blown 355 was a slug off the line due to a big cam but no stall / gears.

i bet if he ran it at the track, and the tune was decent, he would still run in the same MPH, but it would feel like a dog compared to the old setup, stock, simply because of the lack of torque.

Force X length = what you feel. you chop off a 305's cylinder pressure below 3000 rpms and you will feel it missing, unless you add gears (length) or stall (length) to (X) the force at the motor.

 

What has happened here is a classic mistake. The tbi is the last thing holding the L03 back, which this guy has. The cam you have in there now isn't really all that big. It is comparable to the LT1 cam. The biggest thing holding you back is the heads, which don't even come close to maxing out the tbi system. Why in the world did you put a carb on that thing in the first place? I say check the timing with a gun too. A lot of tuning is in store for you, but be prepared to yield little to no gains with your upgrades over what you had stock.

 

3.42 with a T5. So ye, that helps. And I do understand what you are saying.

I still think he will feel more torque if he bumps that timing up to 10 degrees instead of 0 though. I know running a blower you probably like to keep the timing conservative, but in his case I think it will make a difference.

 

I agree with getting new gears and a stall.