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1HOTGMCJET
07-20-2000, 08:19 AM
Looking for any information or insights on this boat - I am in the process of redoing mine and am open to suggestions............

DavidR
07-21-2000, 09:40 PM
There was a gentleman that ran one of those on a local lake when I was growing up and I always liked the way it looked and ran.
It ran a 350 Olds motor w/ a Berkeley Jet-a-vator (from what I've seen, that seemed to be a popular set-up on those boats) and it ran forever.
What are you looking to do with the boat?

1HOTGMCJET
07-22-2000, 07:31 AM
What are you looking to do with the boat?[/B]
Just fun/fast running mostly, but also some skiing/tubing/wakeboard/kneeboarding and a little fishing - everything from inland lakes here near me to St. Clair and Huron.......by the way, mine is also a 350 Olds/Berkeley JE (no jetovator), but gonna install a electro-hydraulic Place diverter and put in a big block Chevy - having the pump done right now - impeller suggestions?

DavidR
07-26-2000, 06:52 PM
What cid is the big block and what has been or is going to be done to the motor?
Get ahold of CP Performance @ (800) 225-9871
(they now manufacture Berkeley jets) and ask them to send you a copy of the rpm / horsepower absorbsion information on the various impellers. That will give you an idea of where to start. Your best bet will probably end up being an "A" impeller as it provides a good compromise on holeshot and top speed ( especially with a torquey 454).
If you use an impeller by a manufacturer other than Berkeley get this info from them as specs on other impellers sometimes vary by quite a bit even being the same designation ("A","AB",etc.).
Let me know if I can help.

MichaelRP
06-21-2012, 01:24 PM
What cid is the big block and what has been or is going to be done to the motor?
Get ahold of CP Performance @ (800) 225-9871
(they now manufacture Berkeley jets) and ask them to send you a copy of the rpm / horsepower absorbsion information on the various impellers. That will give you an idea of where to start. Your best bet will probably end up being an "A" impeller as it provides a good compromise on holeshot and top speed ( especially with a torquey 454).
If you use an impeller by a manufacturer other than Berkeley get this info from them as specs on other impellers sometimes vary by quite a bit even being the same designation ("A","AB",etc.).
Let me know if I can help.

I just purchased a 1979 CobraJet with a 350 Old/Berkely setup, not sure how to tell what kind of setup it is to be honest. I don't know a whole lot about this boat, and I am looking for any help I can get. The boat is not currently running, trying to trouble shoot why its not firing, turns over plenty just won't fire a cylinder at all. Any help would be appreciated...

79cobrajet
07-30-2012, 05:46 PM
I just purchased a 1979 CobraJet with a 350 Old/Berkely setup, not sure how to tell what kind of setup it is to be honest. I don't know a whole lot about this boat, and I am looking for any help I can get. The boat is not currently running, trying to trouble shoot why its not firing, turns over plenty just won't fire a cylinder at all. Any help would be appreciated...

Hello, I was wondering if you had ever gotten any useful info on the GMC CobraJet boat... I have a 1979 , 16 1/2 ft. that I just got and I am having one heck of a time locating info on this desighn too.

79cobrajet
07-30-2012, 05:47 PM
Looking for any information or insights on this boat - I am in the process of redoing mine and am open to suggestions............

Hello, I was wondering if you had ever gotten any useful info on the GMC CobraJet boat... I have a 1979 , 16 1/2 ft. that I just got and I am having one heck of a time locating info on this desighn too.

MichaelRP
08-04-2012, 02:19 PM
Well I haven't found to much out about it yet no, what I do know is in the original post, I rebuilt the holley on mine and it is running like a beast, great boat, I have people I can ask if you have specific questions about the CobraJet

79cobrajet
08-05-2012, 05:58 PM
I really don't have specifics, at this point I will take anything I can get on this CobraJet. If I could it would be awesome to find the original specs on it , hull, stringer configuration, original wiring diagrams etc. etc.
I just did get this boat and the speedometer and fuel gauge do not work , the D ring in front bow is loose so I pulled the gas tank to get access to the bow area and in the process of cleaning out the bow I found that someone replaced the floor, how nice , right? Not really, it appears that the floor board was replaced to cover up all the rotten crap below, it is going to be my next big project.
So the more I can learn about this GMC CobraJet the better maybe I can refurbish it to specs.
It may be original other than the fake over floor, I am told the engine is a 350 Olds rocket and the engine looks original but, there again , difficult to tell for sure. Controls look authentically original also.
So anything will help at this point, thanks by the way for the reply here too.
Dave

MichaelRP
08-07-2012, 11:31 AM
I really don't have specifics, at this point I will take anything I can get on this CobraJet. If I could it would be awesome to find the original specs on it , hull, stringer configuration, original wiring diagrams etc. etc.
I just did get this boat and the speedometer and fuel gauge do not work , the D ring in front bow is loose so I pulled the gas tank to get access to the bow area and in the process of cleaning out the bow I found that someone replaced the floor, how nice , right? Not really, it appears that the floor board was replaced to cover up all the rotten crap below, it is going to be my next big project.
So the more I can learn about this GMC CobraJet the better maybe I can refurbish it to specs.
It may be original other than the fake over floor, I am told the engine is a 350 Olds rocket and the engine looks original but, there again , difficult to tell for sure. Controls look authentically original also.
So anything will help at this point, thanks by the way for the reply here too.
Dave

The CobraJet I own used to be my fathers boat, we don't talk a ton, but I will do what I can to see if he has more info on CobraJets.

79cobrajet
08-07-2012, 05:51 PM
That would be awesome if he does have anything, anything at all, I would greatly appreciate it .
Back to your Jet though, did you change the carb out yourself? this one here has the original 4 bbl
and it is fickle at best, if I get her warmed up and try to full throttle (gun it ) she stutters badly but as I lower the throttle it will pick up
again and then to get it to go higher rpm's I have to feather it , raise the throttle and lower and increase throttle position a
little higher each time til it gets up there pretty good, someone else told me that it was nick named a "bog -erator" because the original
carbs bogged out on the secondary plates when they open. did you experience this too?
btw , what part of the world are you in ?