Carb tuning - Starting

[redefined]

Ok guys so this is my first carb motor I've owned other than my karts that I race, heh!

So there are a few things that I've noticed and maybe it's in the carb tuning, wrong carb for the motor, or something unrelated to the carb all together. Any input into the following things would be appreciated.

1. Cold starts. In the summer, 2 pumps of the gas it it seems to fire up just fine. When it's cold outside or sometimes in the summer weather it takes 5-10 and it takes a while to crank over.

2. Hot starts. Drive the car for 20min, say to Subway to get some lunch. Now just run in to grab a sub and when you come out it's not really wanting to crank. Or it will, but you just gotta crank it a few times and give it a little gas.

3. The smell. This is also my first classic car, it's a 68 Camaro. Now this might not have anything to do with the carb, maybe it's just the exhaust but a 5min drive and anywhere you walk into they'll be able to smell the fumes.

Are these all normal things that you just have to deal with in a carb motor? A couple of these reasons are making me really want to do an LS swap and go fuel injected haha

The car is going to be used for weekend/nice weather, track days/time trials, and autocross. The wife loves it too and would like for us to take it out more but we don't always want to smell like exhaust at dinner! haha

Thanks in advance!

[GregWeld]

Originally Posted by redefined

Ok guys so this is my first carb motor I've owned other than my karts that I race, heh!

So there are a few things that I've noticed and maybe it's in the carb tuning, wrong carb for the motor, or something unrelated to the carb all together. Any input into the following things would be appreciated.

1. Cold starts. In the summer, 2 pumps of the gas it it seems to fire up just fine. When it's cold outside or sometimes in the summer weather it takes 5-10 and it takes a while to crank over.

2. Hot starts. Drive the car for 20min, say to Subway to get some lunch. Now just run in to grab a sub and when you come out it's not really wanting to crank. Or it will, but you just gotta crank it a few times and give it a little gas.

3. The smell. This is also my first classic car, it's a 68 Camaro. Now this might not have anything to do with the carb, maybe it's just the exhaust but a 5min drive and anywhere you walk into they'll be able to smell the fumes.

Are these all normal things that you just have to deal with in a carb motor? A couple of these reasons are making me really want to do an LS swap and go fuel injected haha

The car is going to be used for weekend/nice weather, track days/time trials, and autocross. The wife loves it too and would like for us to take it out more but we don't always want to smell like exhaust at dinner! haha

Thanks in advance!

Sounds to me like you have either an old battery on it's last legs --- or more likely -- some not very good electrical connections…. which is where I'd start.

Super clean and tight batter connections #1…

Then go to where the GROUND is connected to the car (not the battery) and take it apart (off the car) and clean all the corrosion etc or put a new end on it -- and make sure it's going to CLEAN BARE METAL wherever it's connected.

Then I'd go to the starter and make sure you have a good clean well connected POSITIVE ---- DO THIS WHILE THE GROUND IS COMPLETELY DISCONNECTED FROM YOUR CAR - Disconnect the GROUND (-) from the BATTERY.


Once you have that done -- go back and see if the car starts any better….


Next thing I'd do is to check the TIMING…. not sure what motor you have but your idle timing should be 12 or 14 degrees… if it's retarded -- it will crank hard -- and if it's too advanced it will turn over easier but not start well…


I'd do these things before you mess with the carb.



So if you have your timing set for "initial" (idle) properly… and you've made sure you have really good battery connections… NOW I'd go to the carb.


You didn't say what kind -- or include a photo… And we don't know what engine you have either - so this is a bit tricky to try to walk you through any adjustments.


Sounds to me like your engine is "pig fat" -- meaning RICH…. which could be why you smell like exhaust fumes.


It could also be LEAN -- which causes the car to smell like it's RICH… odd I know - but when they're too lean they don't burn the fuel well.


You really might want to consider finding a good hot rod shop in your area and having them help you with this stuff.

Tell us where you are and maybe someone on here can make a recommendation.

[GregWeld]

BTW -- Didn't you buy this from a member here?? Why not ask him directly about what settings etc --- or did it always run crappy??

[redefined]

Originally Posted by GregWeld

BTW -- Didn't you buy this from a member here?? Why not ask him directly about what settings etc --- or did it always run crappy??

Sure did. Hate bothering him though haha. Figure he'll see it here and can respond if he'd like, it's not his problem!

It doesn't 'run' bad once it's going it's solid. Never had it stall or anything but again, my first SBC, first carb, first classic car etc. I'm used to BMW race cars, not this haha!

Great advice too, I've never had to deal with timing and what not. I'll look into all of that! Thanks for the info!

Here is the motor 350 SBC:

Eldelbrock TEC 200 Aluminum Heads
COMP Cam 12-612-5 Solid Lifter Cam
Roller Rockers
Ceramic Coated Headers
Holley Competition 750 cfm
MSD Ignition
OEM Forged Crank
OEM polished rods
TRW pistons w/ floated wrist pins
Balanced rotating assembly
ARP Head Bolts & Fasteners

And a pic:



Also for timing this sticker is under the hood, was there when I got it earlier this year.

[TheJDMan]

Entire books have been written about Holley carb tuning, far too much detail for this forum. However, if you go to the Holley web site they have an series of videos on the various internal systems and how to tune them. Just FYI, 34-36 total timing is just about right for a SBC.

[Vince@Meanstreets]

sounds like your in need of a good tuner. Im willing to bet the car went to a different climate and or altitude so things maybe are off.

Carb engines will smell like fuel, its what they do.

[redefined]

Originally Posted by Vince@MSperfab

sounds like your in need of a good tuner. Im willing to bet the car went to a different climate and or altitude so things maybe are off.

Carb engines will smell like fuel, its what they do.

Big time, from CA to GA. Haha! Going to have a buddy bring his timing light over to check timing. But based on the sticker in the picture above I think there is a little to much timing in it, which could cause my hot start issue.

Thanks guys! Sounds like it should be an easy fix with a knowledgeable tuner.

Anyone know any good tuners in the Atlanta area? All the guys/shops I know are less carb/SBC/BBC and more 'new school' haha.

[intocarss]

Check the starter too.. IMOHO that starter always cranked real slow but the car always started so i left it all in. I honestly don't remember what jets are in it and if there is a power valve or not ( i don't run power valves) YES i always smelled the exhaust and some fuel... I'm immune to it ..AND YES IT SHOULD BE TUNED FOR YOUR CONDITIONS

YOU ARE MORE THEN WELCOME TO CALL ME ANYTIME (YOU'RE NOT BUGGING ME) AND IF I CAN AND I CAN REMEMBER,, I WILL HELP YOU

[redefined]

Originally Posted by intocarss

Check the starter too.. IMOHO that starter always cranked real slow but the car always started so i left it all in. I honestly don't remember what jets are in it and if there is a power valve or not ( i don't run power valves) YES i always smelled the exhaust and some fuel... I'm immune to it ..AND YES IT SHOULD BE TUNED FOR YOUR CONDITIONS

YOU ARE MORE THEN WELCOME TO CALL ME ANYTIME (YOU'RE NOT BUGGING ME) AND IF I CAN AND I CAN REMEMBER,, I WILL HELP YOU

Thanks!

I'll try to get someone that knows about carbs, and read a lot about them, over to the house to check it out! Going to also toss a timing light on it and maybe dial it back a touch.