racintang

I want to know what everyone has there carb settings at for a Holley 600. I keep getting a bog on the bottom end and want to what everyone is running for primary, secondary, type of accel. cam and if you have blocked anything off?

I am using an RB intake and exhaust with a straight pipe. Stocking port.

vipernicus42

iTrader: (4)

a 600 on a stock port?

That would be why you've got the bog. You should be running the RB 465CFM holley. Ask them, and they'll tell you (what they told me in an e-mail) that the 600 is great for street port engines, but if I were to buy one and slap it on my stock port until I get my engine ported, the stock port would bog because of the huge carb on it.

Remember, bigger isn't always better. Too much air, or too much fuel in the mixture will mess things up. You might be able to re-jet it or something to take some of that bog out, but considering RB modified all the carbs themselves.... you may or may not have alot of breathing room

So, easy solution: get your engine ported :P

Jon

Rx7carl

Jon hit most of the high points so Ill just add a couple of things for you to try. Get a secondary spring kit and try stiffer springs to keep the secs from opening too early, and an accel pump cam kit and try to tune out the bog. And a better description of the bog would help. At what RPM's? does it happen only when you mash it?

racintang

MAinly bogs at low RPMs when a smash it. I can eas it up and then it will go. I have a Holley 450 w/ Mech. secondaries but it did the same thing. I had 57 primaries on it but I did not know where the secondary jets where at.

Rx7carl

This isint a mechanical secondary carb is it? Try the stiffer spring, and check the accel pump operation.

racintang

It is a mech. secondary. Is that a bad thing. I can always send it back to summit racing

Rx7carl

Not necessarily bad, but with mech secondaries, and the fact that its over carbed, itll ALWAYS bog when you mash it. You just need to retrain your right foot so you dont bog it.

racintang

If 450 cfm is to big what size would you reccomend for the car. I don't want to pay the $500 for RB's carb. Street Driven.

Rx7carl

Oh my bad, I thought you were still talking about a 600. But youll still have a bog by slamming it open. Even nikkis modded to mech secondaries do that. Again, retrain your right foot to modulate the throttle and not just mash it. Vac sec carb you will be able to tune when it opens with the different springs in the tuning kit.

racintang

What jet setting do you think would be best.

Rx7carl

Cant really say for a Holley, better to let someone whos running one give you a starting point. They are square bore carbs and the fuel delivery curve will be different that the Nikki.

racintang

Let me ask you another question? Since I have put on the new intake I seem to not have enough pressure for the power brake booster. I can only slide to a stop now becaus eI'm pressing so hard to stop. I have the vaccum line hooked up to the RB intake.

Rx7carl

Is it hooked to the right place on the intake? Forgive my ignorance but Im not too familiar with the RB intake, other than seeing it in pics.

excitingleopard

This appears to be one lively conversation.

BTW...Maybe this "bog" isn't really the problem you're looking at. Your car won't take off just because you're pushing the pedal down real hard. Do that, and you'll basically choke the engine out with fuel before it can ignite. I think.

Maybe I'm full of ****. Just something to think about.

racintang

there is only one vaccum line coming off of the intake

Rx7carl

Are you sure theres no leak?

racintang

I tried spraying strating fluid around the base of the carb and it dosn't do anything. I do have a 1 inch spacer under the carb. Could that be a problem?

Rx7carl

I meant a leak in the hose somewhere. If your losing vacuum, your booster will be weak.

Rx7carl

Another idea, with the engine running, disconnect the hose from the intake and see if theres vacuum there. Maybe RB didnt drill the hole into the intake?

racintang

I pulled the vaccuum line line off and I heard a hissing sound before the car cut out.

1. Could there be not enough vacuum being pulled from the intake? What should the vacuum pressure be?

Rx7carl

Well if it was enough of a vacuum leak to kill the motor, then that is probably ok. Maybe your booster is kaput?