High HCs at one exhaust- Where to start?

Guest

Hi Jack ...need help.

Went to get motor smogged in Arizona and failed miserably. High HCs. I put it
on an exhaust gas analyzer, and found the
driver's side header at 1200PPM!!! Right bank
is 300PPM. That was as good as I could get it, despite adjusting timing and mixture screws. I have a brand new Holley Avenger 670, one year old plugs with 300 miles, new wires as well. Performer intake. Mild crane cam and roller rockers. The left valve train area has a slight tick from time to time. Perhasps valve adjustment needed? Also get
popping through exhaust when down shifting or taking out of gear at moderate RPM. Ocassionally get a backfire at startup, even with brand new carb. (this carb has backfire protection) Overall, the performance is generally poor on this 5000 mile motor. Something is wrong. Thought the new carb would fix it.

What should I check? Plugs, wires, valve springs?

Advise appreciated.
Thanks, Tom

Thanks, Tom

4/25/014:22 PM

Original Post

<ul id="{%=id%}ButtonGroup" class="button-group h-popup-buttons even-button-group even-1">
    <li id="{%=id%}Okay_buttonContainer"><a id="{%=id%}Okay" href="javascript:void(0);" class="button success no-margin-bottom h-alert-modal-ok-button" role="button">OK</a><script type="text/javascript">
        (function() {
            function {%=id%}Okay_click(event, data) {
            {%=id%}Popup.hide();
        }
        
                $('#{%=id%}Okay').on('click', {%=id%}Okay_click);
        })();
    </script></li></ul><a href="javascript:void(0);" class="close-reveal-modal" aria-label="Close Modal">&#215;</a><div class="last-modal-focus focus-utility-element" tabindex="0"></div>
</div>
<script type="text/javascript">
        (function() {
            {%=id%}Popup = new SS.Popup.ModalPopup('{%=id%}');
        })();
    </script>

Skip to main content

Membership Required

Remove From Your Block List

Manage Follow Preferences

Block

Please wait...