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ZZ4 350/355 Question Please

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Old Jun 11, 2008 | 07:45 PM
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St. Jude Donor '10
Default ZZ4 350/355 Question Please

I am seriously considering a swap out on my Red 77 and taking the tired old 80K mile 350 out and replacing it with a GM Crate ZZ4 350. I was told if I buy the turn key version I might run in to clearance difficulties with the ZZ4 on the original hood. Question to all of you that know one heck of a lot more about this than me is have you done it, have you seen it done, do you have suggestions about whether or not to try it, and while asking the best people on this planet about the issue can you give me thoughts on the TH350 issues I might encounter as well. I only ask that you don't tell my wife about the swap out yet, its kind of a secret.
Thanks for your help in advance.
David
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Old Jun 11, 2008 | 07:52 PM
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i was actually looking at the same crate

i have a 78 and would like to know the answer as well.
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Old Jun 11, 2008 | 08:01 PM
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Put a ZZ4 in this 69 and the owner loves it.The trans. is a wide ratio Muncie with a 3:36 rear end.The car is very nice to drive and has quite a bit of punch.The intake manifold came on the engine and fits under a stock small block hood.
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Old Jun 11, 2008 | 08:38 PM
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I have a 1980 and I swapped a ZZ4 in about 9 years ago. It fit under the stock hood with a Q-Jet then, and I've since put a TPI on it with no problems concerning the hood clearance. Good luck!
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Old Jun 11, 2008 | 08:38 PM
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The problem with the turn-key option is that the serpentine belt system is pushed too far forward on the engine for fan clearance on the rad. The ZZ4 has a long water pump and this is where the problem lies. If you go to the short pump which you have to do then you have an issue with aligning the alternator, power steering pump, and AC as the brackets push them too far forward. You are better off to buy the ZZ4 without the turn-key option, buy a short water pump, a carb and dropped air cleaner and you are good to go with all your original components.

This is my documented install:

ZZ4 Install
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Old Jun 11, 2008 | 08:59 PM
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Great information, thank you. Would you recommend switching to a 4 Speed Muncie from the TH350 automatic as long as the engine is leaving? This is great data folks, thanks so much for the input. The more the merrier and much appreciated. Here is the engine in her now, no beauty for sure.
DavidName:  Engine2.jpg
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Old Jun 11, 2008 | 09:35 PM
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Originally Posted by 77Sleeper
Great information, thank you. Would you recommend switching to a 4 Speed Muncie from the TH350 automatic as long as the engine is leaving? This is great data folks, thanks so much for the input. The more the merrier and much appreciated. Here is the engine in her now, no beauty for sure.
DavidAttachment 47624882
Well, personally I would take a 4-speed over an auto any day. I converted my auto to a 5-speed and it is one of the greatest mods I ever made to the car. I will put my original engine and TH350 back in the car at some point to bring it back to original, probably within the next five years. But for now, I am enjoying the ZZ4 and the TKO.
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Old Jun 11, 2008 | 09:38 PM
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Originally Posted by 77Sleeper
Great information, thank you. Would you recommend switching to a 4 Speed Muncie from the TH350 automatic as long as the engine is leaving? This is great data folks, thanks so much for the input. The more the merrier and much appreciated. Here is the engine in her now, no beauty for sure.
DavidAttachment 47624882

So, if your getting a new motor I'll take those valve covers off your hands. Five bucks each. I'll even pay shipping. heh
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Old Jun 14, 2008 | 07:44 AM
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I thought I might clean them up a bit and then install them on my other 77. Name:  P6010019.JPG
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