? on Tuning Edelbrock Carb

[Chris611]

Earlier this summer I replaced the 2bbl carb on my 1996 5.7L I/O with an Edelbrock #1409 and Edelbrock Performer Intake. Currenty I have the stock settings (metering rods & jets). I am wanting to tune it with the "caburator calibration kit" sold by edelbrock and using the Power/Cruise charts in the manual. Has anyone done this before? I have some questions and was hoping that someone might be able to help.<br /><br />Question:<br />The book says to find the richest power mode I can without changing jets. From what I can tell with what come in the kit, I am there with the stock setting. Is this right?<br /><br />Thanks<br />Chris

 

[tryan]

Re: ? on Tuning Edelbrock Carb

yo. how does it run? what do the plugs look like?<br />try not to run it lean while you are tunning.<br /><br />if you want to make it richer, use smaller rods.

 

[Chris611]

Re: ? on Tuning Edelbrock Carb

It seems to run okay now. I was surprised to see almost no improvement at WOT from the 2bbl to the 4bbl. I would like to go richer on the Power setting. The plugs look good now. <br /><br />Thanks<br />Chris

 

[tryan]

Re: ? on Tuning Edelbrock Carb

the 'logic' is reversed on the rods. for a fixed jet size, a smaller rod tip ( the numbers are stamped on the rods )will allow more fuel in the primary throat of the carb.<br /><br />what is the recommended rpm limit for your motor?<br />4400-4500? are you hitting that #?<br /><br />alot of other factors are involved to get a performance increase. a slight cam change might enhance your new induction. what type of exhaust? logs, center riser, thru hub?<br /><br />i have the same intake and carb on a 351winsor, center riser exhaust and straight pipes on a ski boat. it took larger jets, smaller rods and firmer springs to dial it in.

 

[tommays]

Re: ? on Tuning Edelbrock Carb

the real question is what prop were you useing before and what was your WOT with the 2 barrel carb and what speed were you getting<br /><br />i dont think that a carb and intake manifold alone is going to give the amount of HP and Torque that it takes to make the power you need to spin a bigger prop which is the only way your going faster<br /><br />tommays

 

[bryont]

Re: ? on Tuning Edelbrock Carb

I have just finished troubleshooting and dialing in a Weber 4bbl (same design). I bought the 1409 cal kit from Summit for $46 I believe. I don't know what info is in your manual but reading the carb info web site really helps you understand how that design works. I have a 1995 350 Mag. Use this site http://www.edelbrock.com/automotive/index.html it will help. At the bottom of the tuning procedure will be a chart for tuning a 1409 carb. Edelbrocks site is very good. When I was troubleshooting my bog I disconnected and tied down the secondaries for a while. I saw 500 RPM from 5000 to 4500 drop without the secondaries once dialed in. This was by myself. It stays within the WOT range when there are more people on the boat with a 19p stainless. Speed dropped from 58-59 ish to 53 or so. <br /> So I believe you should be able to get a better top end with the 4 bbl by turning more rpms. If you had the correct prop before then it should be ok now, all depends on how close you are to your WOT limit when you had the 2 bbl.

 

[Chris611]

Re: ? on Tuning Edelbrock Carb

I have a 23 SS prop. That is the same prop that I used with the 2 bbl. Seems with both carbs, I have about the same WOT (4600 rpm) Which corresponds to about 53 MPH. I wonder if there is a rev limiter that is only allowing the 4600. I think 4600 is the top of the range for WOT for that boat. So does that say that the 2 bbl was flowing enough air at WOT and it didn't need the 4 bbl?<br /><br />Only other thing to note. A month ago we were backing the boat off the trailer at the river and hit "something" in the water. The girlfriend was backing the boat up. When she hit it she put it in neutral. When we pulled the boat out later, I noticed that the prop had some rough edges and it looked like the tip of one of the fins was slightly bent. I took a dremel tool and smoothed the edges and bent the one fin back to appear to be the same as the others. Would this damage cause a 5 MPH reduction in speed?<br /><br />Thanks<br />Chris

 

[tommays]

Re: ? on Tuning Edelbrock Carb

you should have the prop reworked it will hurt you speed a lot if any blades are tweaked it hard to tell if they are all perfect unless the prop is on a pitch plate.<br /><br />good prop guys are worth there weight in gold small things like the how the prop is cupped can make you boat much faster<br /><br />with out more go fast things you will not be able to get the most out the new parts <br /><br />tommays