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i have a 76 in need of a rebuild and a limited budget. can i go to flat tops and swap to a p90 head without any difficulty? i don't want to get involved in a stroker build up and would prefer to keep the matching #'s in the car. thanks in advance.
andy
 

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<b>RE: n42 with p90 head???</b>

I have a 76 too and have been researching this topic for awhile. I have been told that its ok to go with flat top pistons with a p90 head in the block you have now. For some reason I am not going to do it though. I am also on a tight budget so I am going to get a 81-83 zx motor and have it rebuilt while I am still driving the car, this way I have less down time(probably about 2 days) I have gotten prices around 850bucks to rebuild and I will install myself. Good Luck!

Craig76Z
 

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RE: Don'

Legal-Z wrote:
i have a 76 in need of a rebuild and a limited budget. can i go to flat tops and swap to a p90 head without any difficulty?
andy

Andy,
You don't really want to put the P-90 on a non-turbo or non-stroker motor. It has a really large chamber, and you will get lower compression than you already have. I would look at the N-42 or the N-47. Both have about the same chamber size, around 48cc's, vs the almost 54 of the P-90. You are talking about a full point lower compression, and your power will fall accordingly. Look at Bryan Little's site for some basic ideas on power increases. Specifically, look at how to tune the carbs right, for that can be significant if they are really bad. I would also look at the HEI conversion, not nescessarily more power, but much more reliable and accurate.
Consider the NGK plugs, good wires, and a good exhaust, from the manifold back. A header will not really make a difference until you start in with a cam, etc.. which is another thought.
My reccomendation is stay away from the P-90.
-Bob Hanvey

PS- here is Bryan Little's web page address, which he just updated.
http://www.geocities.com/motorcity/2824/
 

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RE: Don't do it.

Legal-Z wrote:
i have a 76 in need of a rebuild and a limited budget. can i go to flat tops and swap to a p90 head without any difficulty?
andy

Andy,
You don't really want to put the P-90 on a non-turbo or non-stroker motor. It has a really large chamber, and you will get lower compression than you already have. I would look at the N-42 or the N-47. Both have about the same chamber size, around 48cc's, vs the almost 54 of the P-90. You are talking about a full point lower compression, and your power will fall accordingly. Look at Bryan Little's site for some basic ideas on power increases. Specifically, look at how to tune the carbs right, for that can be significant if they are really bad. I would also look at the HEI conversion, not nescessarily more power, but much more reliable and accurate.
Consider the NGK plugs, good wires, and a good exhaust, from the manifold back. A header will not really make a difference until you start in with a cam, etc.. which is another thought.
My reccomendation is stay away from the P-90.
-Bob Hanvey

PS- here is Bryan Little's web page address, which he just updated.
http://www.geocities.com/motorcity/2824/
 
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