Rebuilt my engine, now it seems sluggish/slow--New Carb?

[Anonymous]

I just rebuilt my engine with mild performance modifications. I added an E0 head and had it fully reworked including grinding in the bowl to unshroud the intake valves, and milled to 50cc's. The block was mainly rebuilt to factory specs, with ..040 oversized pistons.

I took my car out for a test drive and it seems somewhat sluggish. I have a 1969 250 Autolite 1101. The timing is set on 12*. Maybe i just need to tune the carb a little. Any suggestions?

I am thinking my car just cannot breathe. I was thinking about putting on an open element air cleaner to fix that, and was also thinking about adding a 2 barrel carb sometime in the future, with an adaptor. If i did so, what would be a slightly performance but still fuel efficient carb? I have heard good things about the weber 32/36.

Any help would be great. You guys got me this far, and I thank you for all your help.

 

[Anonymous]

Try playing with the timing to see if it likes more or less.

You may need to re-jet the carb, or check your float level.

 

[LaGrasta]

Put down the timing light. Advance the timing until you hear it flutter, then back off. Set it and give it a test ride. If it pings under acceleration, back it off just a tad more. I think you'll find advancing it will make a big difference.
Are you running electronic ignition? Good!

 

[CZLN6]

Howdy:

Be sure to recheck the throttle linkage to be sure you are getting full throttle when you put it to the floor.

You didn't say what distributor you're using? what Block Did you rebuild? what cam did you use? What tranny? What rearend gearing?

Be sure to sort this combo out before you proceed with other mods.

Adios, David

 

[Anonymous]

just to help out...which way is advance again on the distributor? clockwise or counte rclockwise

 

[Anonymous]

ps...is the parking brake on? ask me why I am asking....

 

[PutPut6]

ps...is the parking brake on? ask me why I am asking....

haha, I've been there and can attest to the sluggishness of a car driving around with the parking brake on..... doesn't say much for my parking brake :roll:

 

[LaGrasta]

Full throttle as well as choke being fully off. Check the linkage.

 

[Anonymous]

not to hijack

but I drove it till is was smoldering....now I had all my brakes tightened and I am happy again. I am surprised I didnt burn it up


I mean really...who's light still works indicatig brake is on?

 

[PutPut6]

ok one more and I'm done hijacking..... my brake light is always on.... even when it's not engaged.

 

[Anonymous]

Yea guys, Ive got the pertronix ignition with the flamethrower coil. I was thinking about upgrading to the DSII, but cant justify the time/expense when my pertonix is working great.

I've got the stock 68 distributor, other than the pertronix mods. I just put a new cap and wires on it as well.

The block I rebuilt was a stock 68 block, and the cam I believe was a standard cam, nothing too fancy. I had my machinist grind the valves so it simulated a higher lift cam, but I know it is no comparison to a high lift cam. I regret the stock cam, but don't want to pull it out now.

I have a C4 tranny, it has never had any problems before.

The rear end gearing is stock, no clue what it is.

I'll work on setting the timing when i get home. As for now, im going to run all the unleaded regular gas out, then fill up with plus/premium. Then ill set the timing again.

 

[mugsy]

The vac canister on the dizzy points in the direction of "advance".

I put a Pertronix on my '65 when I got it 7 years ago and then recently put on a DS II. No real change IMHO. So stay with what you got.

There should be a small tag on one of the bolts on the rear diffy cover. That has the ratio listed on it. Look at the bottom left corner of the tag, it should have a single number, then a space and then two numbers. The space is really the decimal, so a "2 54" is really a 2.54:1 ratio. The ratio has a huge impact on the drivability of the car. It is a very valuable number to have and know for future mods, etc.

tanx,
Mugsy 8)

 

[LaGrasta]

Don't bother changing the fuel to a higher octaine. There is no need or real benefit. Plus, you'll get an inaccurate "pinging point" when setting the timing. When you go back to regular, it will ping earlier and you'll just end up having to retime it..