Got the Malibu on the road, but has no power.

[Phoenyx]

So yesterday I got the Malibu insured, inspected, and registered. Gave it a quick (and I'm hoping not a very good) tune and took it for a little cruise. Not impressed at all, but maybe a proper tune will help?

So it has more power than the stock 305, but not much. Cant even do a brake stand with it. I actually think the 305 had more off the line. My quick tune included setting the timing at 12 degrees (with the HEI vacuum unhooked and plugged). And the mixture screws about 1-1 1/2 turns out. I'm thinking it has to be the timing, carb, or maybe the small exhaust (2 1/4")?

The distributor is an MSD Streetfire with the adjustable modulator and adjustable stop inside. I don't know much about those, they are still set how ther were out of the box. Carb is a brand new Edelbrock 600cfm.

Any tuning tips? Could the timing cause this much power loss?

 

[Phoenyx]

Also like to add, I tried hooking the HEI vacuum line into both ported and no ported. Didn't seem to make a difference.

Now not to start an argument, but where do you all recommend it goes? I have looked online, and come up with both answers. Also checked the Edelbrock site, they say manifold vacuum. And I emailed MSD, they said ported.

So I'm looking for some opinions on this. But not any nasty fights.

 

[Blake B]

is this the BA motor you bought from the racing semi truck engine builder? is he not willing to give you help now?

he sounded like a good guy? if he's close, he may be the best reference..

 

[Phoenyx]

is this the BA motor you bought from the racing semi truck engine builder? is he not willing to give you help now?

he sounded like a good guy? if he's close, he may be the best reference..

Yeah, same engine, but he's a scam artist and won't even talk to me now.

I'm thinking it's a timing issue. Just trying to do some more research. i don't know why, but this timing stuff just seems so confusing lol.

 

[DRIVEN]

What's your total timing?

 

[Phoenyx]

I don't even know.

 

[Longroof79]

As Driven suggested, check for total advance. That motor should be putting down some significant power.
Do you have timing light which indicates and can dial in degrees? If not, you can add timing degree tape on to your vibration damper/ harmonic balancer.
I would try dialing in total advance of 36 deg.@ around 3000 rpm. You can start with that and increase or decrease degrees according to how it feels and if it doesn't ping.
Have you ever changed springs and or weights in the distributor?

You may also end up having to re-jet your carb. I would concentrate on the timing first. As for vacuum, I normally use ported.
But again, that can vary between engines.

 

[Finn80CalaisSBC]

I got AFR 1034 heads and a Comp 282S mechanical cam in my 355 with 10.0 compression. I used to use a 750 Carter AFB before I turned to E85. This is how my engine performed the best.
- initial timing at 20, total timing 38 in by 2500 rpm
- adjustable vacuum advance in manifold vacuum, 10 degrees at idle
- mechanical and vacuum advance at idle a total of 30 degrees

I feel that with a cam that has some overlap the manifold vacuum advance helps with the idle and part throttle acceleration. My engine is a dog off-idle without vacuum advance. Of course with a non-adjustable factory vacuum pot you're gonna have too much advance.

Originally the engine had an off-idle stumble. I found that raising the fuel level just slightly above what Carter recommended helped with that.

As for the relation between ignition timing, I once played with my ignition timing at the dragstrip. With 34 degrees total the car had a speed of 104 mph. At 38 degrees the speed went up to 110 mph. So at least my engine seems to like a lot of timing at low engine speed. I'm not saying that yours would be sure to respond the same, but it's worth a try.

 

[richp85elco]

I was going to say that with that cam your power band is moved up and would feel like a slug down low compared to a stock 305 that was designed to have good torque in lower rpms. But going by your sig it looks like you have a higher stall converter so that shouldn't be that bad especially with those gears but your cam does suggest 2500 and up stall. When trying to break stand, how high are you bringing the rpms up, are you babying it or really mashing on it?

 

[Pontiac455]

The engine might of been bulit on HALLOWEEN. A 267 dressed up as a 350.