stock 400 cam upgrade question.
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I have a 86 baja 320 with 400's, someone got rid of the q-jets and put on holley 750's, I now have to rebuild one engine due to a oil gauge line breaking last weekend, ran out of oil before I cought it, sounds like a spun rod bearing, I will be doing both engines so I know they are the same, I don't want to get crazy since I know it takes alot to make a 32 ft straight hull fast, I was going to get suggestions on what cam may be a nice "cheap" couple of hp with the stock heads, or should I leave them alone.
the engines were supposedly 420hp but it is tagged as 400's.
one engine was redone 2 yrs ago, that is the one they had the issue, I wonder is there a cam difference between the 400 and the 420? or is it just the carb and intake setup?
The rebuilt engine sounded like it had a tad more cam in it then the stock engine.
Another reason to do both is to make sure both have the same cam.
the engines were supposedly 420hp but it is tagged as 400's.
one engine was redone 2 yrs ago, that is the one they had the issue, I wonder is there a cam difference between the 400 and the 420? or is it just the carb and intake setup?
The rebuilt engine sounded like it had a tad more cam in it then the stock engine.
Another reason to do both is to make sure both have the same cam.
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the new 525 is a roller camed engine. Griffs post is refering to a 525sc wich was a 420 w/ 250 blowers. Up grade to roller cams if you can swing the cash it will be well worth it.
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Originally Posted by [email protected]
the new 525 is a roller camed engine. Griffs post is refering to a 525sc wich was a 420 w/ 250 blowers. Up grade to roller cams if you can swing the cash it will be well worth it.
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525SC uses the same flat tappet cam. It does have gold crane roller rockers as does a 420. Not sure about the 400 having roller rockers, but it should due to the cam lift.
BTW, a 525SC is a little more than a 420 with blower(its a weiand 177) on top. They were hand assembled and balanced at merc racing. Lower CR, inconnel valves, etc.
BTW, a 525SC is a little more than a 420 with blower(its a weiand 177) on top. They were hand assembled and balanced at merc racing. Lower CR, inconnel valves, etc.