Building my first 455

[2coldout]

Hello,
This is my first time building a 455 for a jet boat. and I have been reading up on what size cam to install I know it's a touchy subject with all the mods and such that can be done. The engine has .30 over forger pistons, totally oil restricted, offenhauser single plane, 10 qt pan.
And was wondering if I should have the stock head freshened up or try to find a set of aluminum heads to top it off?
The only reason I am asking all these newbie questions is most everything I have read is basically trial by fire and I could use someone that has actual 455 jet experience or has been in my shoes. I hate to put in one cam to find out that is one to stay away form.
Any guidance will be greatly appreciated. Thanks

[El Prosecutor]

Hello,
Any guidance will be greatly appreciated. Thanks
HB is a great place to talk about jet boats, but not so great to talk about Olds motors that you are going to keep. Most of the advice you will get here will be to "buy a Chevy and junk the Olds".
If you are committed to keeping the Olds and don't want to be convinced otherwise you are better off going here: RealOlds Power (http://72.22.90.30/phpBB2/viewforum.php?f=7). There you will find the pleasant and enlightening banter of a motley subtype of masochists called "Olds Lovers".

[ck7684]

Go with a full roller with the spring loaded pop-up cylinders so you can swap the cam easily if need be. Then clearance your valves for a large cam. Then again I have a 454 so I'm not sure whats available for olds...

[BUSBY]

give Greg Shoemaker a call ... he used to work for mfg's when they originally installed the 455's, should know the direction you should go toward.
http://www.gsmarine.us/
you can tell him I told you to call, he'll probably give me a hard time ... but it's all good. I used to have a 455 a long time ago ... was a lot of $$$ spent for not much hp, but it was reliable for a river cruiser, always had oiling problems
Good luck
Brian Busby

[BrendellaJet]

these threads always end up with people saying to junk the olds. Decide what you want to do with the boat. If you want a 90 mph hotrod, your dollars are better off spent on a Ford or Chevy. Not that hard to convert. If you want a reliable cruiser then the olds is okay. I definitely recommend going over to the R.O.P website for advice.

[Taylorman]

Hello,
This is my first time building a 455 for a jet boat. and I have been reading up on what size cam to install I know it's a touchy subject with all the mods and such that can be done. The engine has .30 over forger pistons, totally oil restricted, offenhauser single plane, 10 qt pan.
And was wondering if I should have the stock head freshened up or try to find a set of aluminum heads to top it off?
The only reason I am asking all these newbie questions is most everything I have read is basically trial by fire and I could use someone that has actual 455 jet experience or has been in my shoes. I hate to put in one cam to find out that is one to stay away form.
Any guidance will be greatly appreciated. Thanks
It depends what needs to be done to the heads. If they need to be rebuilt with new valves and springs, go aluminum. You will spend almost as much rebuilding iron heads as what you would spend on Edelbrock alum heads ($1500). With alum heads and the right cam and headers, you should be able to make 500 hp no problem.
Go with a full roller with the spring loaded pop-up cylinders so you can swap the cam easily if need be. Then clearance your valves for a large cam. Then again I have a 454 so I'm not sure whats available for olds...
Roller cam and stock heads for an olds should not go in the same sentence.

[TahitiTiger]

Your best bet is to contact Mondello. When I built my 455 olds I talked to them and Tom @ Jet Boat Performance. But Mondello is the olds authority, set me up with a good cam, to go with the set up I have.
http://www.mondellotwister.com/
edit: even though there sight shows all car stuff, they are more than willing to do jet boat set ups, the cam the sold me is a custom grind they do just for jets.

[Taylorman]

Your best bet is to contact Mondello. When I built my 455 olds I talked to them and Tom @ Jet Boat Performance. But Mondello is the olds authority, set me up with a good cam, to go with the set up I have.
http://www.mondellotwister.com/
edit: even though there sight shows all car stuff, they are more than willing to do jet boat set ups, the cam the sold me is a custom grind they do just for jets.
Im sure you had good luck with them but they are the black cats in the olds community. There are much more helpful Olds specialists out there. The guy who now owns Mondello's is a jerk, not helpful, unwilling to spend any time with you on the phone and only wants to sell you part. Duane at hi tech would be who you should call. He can put the whole package together for you.

[TahitiTiger]

Im sure you had good luck with them but they are the black cats in the olds community. There are much more helpful Olds specialists out there. The guy who now owns Mondello's is a jerk, not helpful, unwilling to spend any time with you on the phone and only wants to sell you part. Duane at hi tech would be who you should call. He can put the whole package together for you.
really? when did they sell? Its been 3 years since I delt with them. Do you have contact info for Hi-Tech?

[HalletDave]

really? when did they sell? Its been 3 years since I delt with them. Do you have contact info for Hi-Tech?
Here ya go.
http://www.hi-techperformance.com/