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Discussion Starter · #1 ·
I put in a stage 2 cam and kibblewhite valve springs but it doesn`t run like it should. It feels a bit like a 2-stroke just before it starts pulling. Definitely not as powerful as original in any rpm, except for a little "push" just before the limiter kicks in. I lost the cam card so I can`t check the timing, it seems like the markers does`t line up like they should. After the cam swap it also run richer than before. Help!???
 

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Are you sure that you had the flywheel as the single line and not the double line which is for ignition.

With the flywheel timing mark at the single line, the cam lobes should be down and the three dots on the cam gear should be flush with the top of the head - up - flush with the top of the head.

Did you put the decompression mechanism into the new cam? If so is it installed properly?
 

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Are you sure that you had the flywheel as the single line and not the double line which is for ignition.

With the flywheel timing mark at the single line, the cam lobes should be down and the three dots on the cam gear should be flush with the top of the head - up - flush with the top of the head.

Did you put the decompression mechanism into the new cam? If so is it installed properly?
Changing cams will not affect jetting much if any............
 

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The oem service manual, available here in the sticky, can show you how to check cam timing. You should also be sure your valve lash is set properly.
 

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Discussion Starter · #5 ·
I just checked my cam timing again, and the markers lines up perfectly when the piston is in TDC. Does anyone have a cam card for HC stage 2, I would like to double check with an indicator gauge.
 

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I just checked my cam timing again, and the markers lines up perfectly when the piston is in TDC. Does anyone have a cam card for HC stage 2, I would like to double check with an indicator gauge.
The cam card wont help you anymore then what the timing marks have already told you.................
 

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Changing cams will not affect jetting much if any............
Sound weird, so going from stage 1 to stage 3 jetting should remain the same? My edlebrock don't have jets , but I figured I would still have to adjust for bigger cam. I am not arguing with you willy, just sounds odd when almost every thing you do affects jetting.
 

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The edelbrock does have a jet, it's the thing you're adjusting when you spin it around from the top. That needle comes out and can be replaced with larger/smaller sizes. When you buy the edelbrock they send you a couple sizes of that needle.

I guess I disagree with the cam not changing jetting, at least a jump from a stage 1 to a stage 3. If you don't have to change the jetting then you're not flowing any more fuel, which would be contradictory to the whole point of putting the cam in anyway. I would agree that if you are already jetted pretty close but on the fat side you can throw in another cam and not experience any indications of a lean condition. But if it were me I'd be looking at bumping my mains if I were running stock carbs. Then again, I'm not an expert on jetting and I don't run a wideband so all I have to go by is the butt dyno and a personal tendency to go a bit rich on the jetting.
 

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The edelbrock does have a jet, it's the thing you're adjusting when you spin it around from the top. That needle comes out and can be replaced with larger/smaller sizes. When you buy the edelbrock they send you a couple sizes of that needle.

I guess I disagree with the cam not changing jetting, at least a jump from a stage 1 to a stage 3. If you don't have to change the jetting then you're not flowing any more fuel, which would be contradictory to the whole point of putting the cam in anyway. I would agree that if you are already jetted pretty close but on the fat side you can throw in another cam and not experience any indications of a lean condition. But if it were me I'd be looking at bumping my mains if I were running stock carbs. Then again, I'm not an expert on jetting and I don't run a wideband so all I have to go by is the butt dyno and a personal tendency to go a bit rich on the jetting.
Your, right mad dog I adjust it from the top. There are different needles, but from my experience there is a ton of adjustment on each needle. When I need to adjust , I rich it up till the engine starts to bobble , then lean it up 2 clicks. This has been very accurate so far. I take my raptor to mike at little sahara power sports to dyno and tune if needed, so far I have been right using above method. Super easy to tune, but not a huge hp carp. I wish the 39's were this easy to tune.
 

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The 39's haven't been bad, only ever had to change out mains and raise/lower needles. There are about a half dozen jets in each carb, but just like the edelbrock you don't have to mess with all of them if you put the right size in to begin with.

If this is the case, I'd just have Mike tune it with the new cam. You'll probably want to know how much hp you've gained anyway.
 

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The 39's haven't been bad, only ever had to change out mains and raise/lower needles. There are about a half dozen jets in each carb, but just like the edelbrock you don't have to mess with all of them if you put the right size in to begin with.

If this is the case, I'd just have Mike tune it with the new cam. You'll probably want to know how much hp you've gained anyway.
Thanks, I have been wanting the39's just do not want to always be chasing the right jetting. Since you say they are not bad I may bite the bullet and get a pair. Damn 1000.00 bucks is a lot ..... Might have to wait till spring..
 

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Sound weird, so going from stage 1 to stage 3 jetting should remain the same? My edlebrock don't have jets , but I figured I would still have to adjust for bigger cam. I am not arguing with you willy, just sounds odd when almost every thing you do affects jetting.
Changing cams doesnt change the vacuum intake at the carbs as much as porting or changing the air box or air filter configuration. I remember changing from a stage 2 to a stage 3 and not having to change the jetting at all, but I was running a 3 plugger.............:)
 

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Changing cams doesnt change the vacuum intake at the carbs as much as porting or changing the air box or air filter configuration. I remember changing from a stage 2 to a stage 3 and not having to change the jetting at all, but I was running a 3 plugger.............:)
Thanks willy, i allways learn something new from you.
 
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