Holley 650 DP. What Jets???

[mikemustang289]

I'm running a 302 with AFR heads and the cam is custom 219/[email protected] and about .550 lift. I'm running an RPM intake and longtube headers. I don't have a wideband yet, but I am curious what jets I should be running or if anyone has a good idea

Currently the primaries are 67 and the secondaries 75. I've been told that I should jet up but the car runs excellent as is and the plugs are not white.

Any ideas?

 

[GoinBroke]

You know what they say - "If it aint broke.....). If you want the most you can get though I would buy a jet kit and have it tuned on a reputable dyno shop.

 

[67Dylan]

I'm running a 302 with AFR heads and the cam is custom 219/[email protected] and about .550 lift. I'm running an RPM intake and longtube headers. I don't have a wideband yet, but I am curious what jets I should be running or if anyone has a good idea

Currently the primaries are 67 and the secondaries 75. I've been told that I should jet up but the car runs excellent as is and the plugs are not white.

Any ideas?

I agree w/the 'if it ain't broke...' saying. BUT, if you have to toy w/it then call Keith at AZ Dyno Chip ( azdynochip.com ). He is one of the best in our state & would trust him; he's dyno'd & helped tune a couple of my previous cars.

 

[brianj5600]

I would not pay someone if you are going to buy a wide band. Put the money for dyno tunig into a WB.

 

[65ShelbyClone]

Right, if you already have a laptop, an Innovate LC-1 is about $200 from lots of sellers. $350 if you get the one with a digital display. You'll be able to datalog and see where the mix gets too fat or lean and then tune those areas a lot easier. An LC-1 in next on my list.

 

[67Dylan]

Right, if you already have a laptop, an Innovate LC-1 is about $200 from lots of sellers. $350 if you get the one with a digital display. You'll be able to datalog and see where the mix gets too fat or lean and then tune those areas a lot easier. An LC-1 in next on my list.

I agree. That is better advice than I gave; I totally forgot about the LC-1 . Mike, if you are mechanically inclined, as I assume you are, then the LC-1 would serve your needs better as you can tune to various weather conditions and use it whenever you have the need. The dyno tune is a one time deal and leads no room for growth... my bad.

 

[mikemustang289]

What about the LM-1? What is the difference between the LM-1 and LC-1.

 

[chepsk8]

I run a 600 DP on the Cobra, 65/72 with a stock 5.0.

Watch the plug color and exhaust tip color for each jet change. You probably are very close as is. Try tuning the other carb systems once you get the jets set.

 

[67Dylan]

What about the LM-1? What is the difference between the LM-1 and LC-1.

The LM-1 includes a digital display & allows for internal data logging while the LC-1 you need a laptop.

Here you go:
http://www.innovatemotorsports.com/products/MTS_grid.php

 

[65ShelbyClone]

The dyno tune is a one time deal and leads no room for growth... my bad.

That's true, but the wideband alone doesn't allow for optimising power......just gettting the mixture where you want it. It can be done by feel, but I bet no one here can tell a 5hp difference with the butt dyno.

 

[67Dylan]

That's true, but the wideband alone doesn't allow for optimising power......just gettting the mixture where you want it. It can be done by feel, but I bet no one here can tell a 5hp difference with the butt dyno.

Agreed. I also agree, and don't think I lead anyone to believe, that the wideband isn't the only tool used for tuning. There are plugs to read, exhaust temps to measure.... but it is a great tool nonetheless.

 

[SoCalCruising]

I run 68/78 jets. My carb was professionally tuned. I'd say your jetting is pretty close.

 

[65ShelbyClone]

I'll have to go and look at the floatbowls on my 650, but I think I have high-60s primaries and mid-70s secondary jets too. Runs pretty well, but I haven't checked the plugs.