Since I first got my motor running last fall I've felt that the exhaust just plain stunk, smells like unburned fuel. The smell just hangs in the air, my clothes wreak, and generally irritates my wife. If I had to describe it, it reminds me of the smell a lawn mower leaves on you, or other 2 stroke motor.

No one elses cars that I've been around smell like this - even cars with bigger cams. Could this be caused by rich condition ? Timing appears to have no effect on the situation.

Any ideas would be appreciated.

Pretty sure stink of unburned gas (especially if it burns your eyes) is a huge sign of a rich condition.

pretty normal stuff with any cam with some over lap because the unburned fuel gets sucked out into the exhaust(or should i say pushed out lol) anyway.......the carb has alot to do with it as well.........holleys which i deal with can be tuned to over come the problem i have not really done anything else with other carbs.........your running rich in your idle circuit it would take some patients for the novice car guy to take care of the problem.........just turning in the idle mixture screws just dont take care of it.......

Are you running manifold vacuum to the distributor?

If you're not seeing any smoke, you're probably just smelling good ol' uncatted exhaust. Personally I like the smell, but it does get on you pretty easily, and it does stay with you. I was idleing at an air pump at a gas station filling up my rear air bags. My air valves are located behind the license plate. Just spending a minute behind the car setting the pressure was enough to get me "stinkin'" the rest of the day.

DDennis what more then messing with the IMS's does it take to elimanate the smell as much as possible. I don't mind going to work and stinking or going home and stinking, but im sure people don't like it when I go to class and smell like a gas station haha :rolleyes:

well, you could always run some plugs to the tailpipes for flamethrower "afterburners"...... get that little bit of extra thrust and take care of the stink all in one go! graemlins/beers.gif

Please answer Mike ( greybeard's) question, beleive his is the only reply that might help.

Greybeard/427L88, no it is not hooked up. Timing is 18 deg. initial, and 38 total.

427L88, thanks for the feedback on my posts about lackluster power - my compression is up with the 97cc heads, pulls better, and just seems to run better since adressing the cam/compression mismatch. Exhaust is next, and gears if I can swing it later in the summer.

??

what kind of carb are we talking about here?

if its a holley you most likely need to adjust the throttle blade/transfer slot relationship.

read this post from the engine forum
adjusting throttle plates (http://www.chevelles.com/forum/ultimatebb.php?ubb=get_topic;f=9;t=016175)

edelbrock 750....

i have an edelbrock 750 on my biscayne, and it ran fine out of the box. ive never had it apart and wouldnt know where to start on it, i dont even know if they have transfer slots.

what fuel pump are you using? have you checked the fuel pressure, or the float setting?

with the engine running and air cleaner off, take a flashlight and look at the boosters. if there is fuel dripping from the boosters you either have too high fuel pressure or too high float setting.

originally posted by Midnight Marauder

Edels are real finicky abotut he pressure, best to knock it down to atleast 6 psi. Also make sure you checked the float level, i've found more often than not its not set right from the factory. Plugs being black could be other issues as well but yes, run a regulator with a pressure gauge Edelbrock Performer Carbs & Fuel Pressure Reg (http://www.chevelles.com/cgi-bin/forum/ultimatebb.cgi?ubb=get_topic;f=9;t=010671)

Jegs sells an additive to make it smell like cherries, grapes, and strawberries! :D

Originally posted by BigBlockBeaumont:
Greybeard/427L88, no it is not hooked up. Timing is 18 deg. initial, and 38 total.Justa WAG, but I suggest hooking up the vacuum and see if that makes a difference. I think you could likley use a lot of extra advance at idle - you would likley have to reduce your idle speed afterward. Without this, you might be?? cracking open the throttle inadvertently to get the current idle speed.