Holley 350 rich as can be.

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dennday67

dennday67

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So I installed my holley 2300 350 cfm and modified aluminum intake last night. Used a 3" long piece of aluminum angle to adapt the lokar throttle and kickdown (still needs to be adjusted as I cant get more than 3/4 throttle). I rebuild the carb to factory specs (one jet size lower than they come new if I recall). The 225 is all stock except for the HEI and ngk plugs. I was wondering what size jets everyone with this setup is using so I can get in the ball park. I know elevation makes a difference just try to get it closer then I can dial it. She fires right up and sounds strong just very very rich.
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Went ahead and pulled the bowl to double check whats in it. 60 jets, 8.5 pv, orange cam on hole one, .015 acc shot lever at wot. Float is set just below the sight hole. Going to pick up a pair of 56s after work tomorrow and see how that goes.
 
Make sure your ignition is working perfectly. Ensure it is grounded well. A weak spark can cause what you are seeing.
 
Thanks for the reply. The ignition is working correctly. The module has its own separate ground going back to the redundant ground on the firewall (ran into that issue after paint). Before the swap with the holley 1945 the ngk plugs where light brown.
 
The 8.5 PV seems a bit high; it will be very easy at moderate cruise and low engine RPMS' to open the PV at that vacuum level; a 6.5 might be better.

Is the richness at idle in the garge or did you drive it around? If at only idle, I'll ask the dumb question of why the idle mixture screws did not fix this....
 
It was running while in the garage only. I could tell on startup that it was rich because of the 5 different carbs that I've had on it it smelled rich like the bbs. I have a 6.5 PA I can put in it. When I rebuilt it I set it up based a pond the info I found to be how it would be out of the box. I haven't driven it yet as I'm still working on adjusting the lokar throttle and kickdown. I'll put 56 jets (like I've read others have switched to and the 6.5 pv and see how it runs. A Co worker told me to move the throttle post down to the next hole to achieve full throttle.
 
OK, you likely need to first adjust the 2 needle valves for idle mixture. They are the small screws down on each side of the metering block. Start with them at 1.5 turns out from fully in and then adjust both 1/4 turn at a time CCW (to go leaner) 'til the idle drops and then adjust back out a bit. (When you turn them fully in, don't turn them in gorilla tight, just lightly seated.)

A lot of your garage running, even revved up, is on the idle circuits. Even revved up, it's mostly on the progressive circuits which are derived from the idles. Main jet changes are going to have very little effect in in the garage.
 
Make sure you are pulling through idle circuit, transition slots should be square right below the butterfly. Also make sure PV is not leaking. Looks like you already have the fuel level set. Baseline idle mixture screws. A hand over the carb will tell you if you are running lean, the idle will increase. 350 wasnt stock on any slant, what specs are you rebuilding to? Float level might vary.
 
If you do not get any change with the mixture screws or they are all the way in you may have exposed transfer slots. If this is the case you will have to drill some small bypass holes in the throttle plates. Other issues could be the main body is not square on the metering block surface and you are having some leakage around the gasket surface. This would require some filing of the main body surface.
 
Sorry I forgot to make mention that I did adjust the a/f mixture screws slowly 1/4 at a time till it stumbled then slowly backed them out till the rpm no longer increased then divided that by two. Seems like it was pretty close to 1.5 turns out. The float level is set where the gas is just below the sight hole.
 
Sounds like you are on the right track with jetting, lower rated power valve and float adjustments. If you go too far on any of those you will notice a driveability issue.
 
For a street car I never did like "All In early". A short curve with as much initial as it will stand when hot and make sure with vacuum you don't get over 45 or so.... If you have upped the compression 45 will be too much.
 
I know the real test would be to get it out a long stretch of road with no traffic and run it up then shut it down and pull the plugs to see how they look but wanted to try getting it close first. Not even the bbs left the plugs that black (close though). I chose the 350 because I'd like to install a turbo later but I wanted to make sure this carb would run right. I've got 4 4150s, 2 yfs, 6 motocrafts 2150s, a wcfb, holley 1920, holley 1945, a q jet, and a TQ. People keep giving me carbs because I like messing with them.
 
Motor is all stock except HEI. Valves are adjusted correctly and timing is at 10' btdc. Ngk plugs gapped to .045.
 
When I ran too cold a plug in a 440 they looked like yours. For some reason that same engine liked Autolite plugs better.
 
If your actual plan later is to go turbo as you say, even when you do get it running good, you'll have to disassemble it and then cut it up and modify it and rejet to work for a turbo app.

Maybe if that's the carb you want to use, it'd be better to default to the last carb yo were running and save the 350 for the turbo time?>
 
I think I had autolites in before the hei upgrade and they looked like these. Plug choice anymore seems hard with all the China crap we get anymore. I used to prefer campion but lately I've had better luck with ngk. The ones that are in is the ones Dan stern recommends with the hei upgrade so I'm not sure if it's too cold.
 
Serj22 said:
If your actual plan later is to go turbo as you say, even when you do get it running good, you'll have to disassemble it and then cut it up and modify it and rejet to work for a turbo app.

Maybe if that's the carb you want to use, it'd be better to default to the last carb yo were running and save the 350 for the turbo time?>
Click to expand...

Without knowing the history of the carb I wanted to make sure it would even work. I have one holley 4150 that I bought 2nd hand that ran great for 2 years then the internals eroded and plugged the carb up. If I'm going to spend the money on going turbo I wanted to make sure I'm starting with a good carb.
 
nm9stheham said:
^^^ That was my thought exactly....start with a known quantity when doing the turbo.
Click to expand...

Thanks. As an industrial mechanic that works 12 hours a day I know if you dont start with good working parts you will end up chasing your tail plus I enjoy tinkering with carbs enough that I'm okay with redoing it for the turbo..... or there is another 2300 in the carb pile but it's not in as good of shape. I think the 2 YFs would make a cool dual 1 barrel setup but not for me. When I get bored with the /6 I have a 71 360 that I have about $5th into sitting in the corner but still need to go thru the 727 and 8 3/4.
 
I put the 56 jets in this morning along with the 6.5 pv. This time when I went to adjust the a/f screws I dug out my vac gauge instead of doing it by ear. She's sitting just a hair below 14 inHg. I double checked the float level and brought it up just a hair. I still keep getting a small fuel leak from the fitting adapter so I'm going to try a new gasket. I think the 56 jets may be a bit too lean as now at idle there is a slight burp thru the exhaust that never happened before. I might step up to a set of 58 jets. Our elevation here is 1066 ft above sea level and holley says to go down one size for every 2000 ft so the 60 jets should be about right but every Carb Ive done I've always had to go down a few sizes.
 
If you advance the timing at idle and it picks up RPM, the engine wants the timing. Distributor will likely need to be altered to keep total timing at a reasonable level.

Main jets have zero to do with your idle if the engine is tuned properly.

Get the initial timing set properly FIRST! Then start tuning the carb idle settings.
 
Drop them jets down to .045 and see if things improve. Considering .072 is a good starting point on a 650-750 your .060s may be a little too much.
 
I was also thinking I needed to add a few more degs of timing. Ive heard some like it around 16 degs. I havnet taken it out to test drive it because I waiting for my new throttle return springs (the lokar ones don't work well with the bracket) and making sure there are no more leaks.
 
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