SoCal Jet Boats

Tech Talk => Projects => Topic started by: jet fever on December 23, 2009, 01:24:36 AM

Title: 455 swap to 454
Post by: jet fever on December 23, 2009, 01:24:36 AM
can i just bolt in 454 mounts? what else do i need to do?
Title: Re: 455 swap to 454
Post by: crewchief22 on December 23, 2009, 05:16:25 AM
The mounts are the main thing that you have to change within the boat itself, but all of the marine excessories are different between the 455 & 454 (bell housing (if used), exhaust, water pump block off...).

 
Title: Re: 455 swap to 454
Post by: GT Jets on December 23, 2009, 07:45:21 AM
A 455 Olds to 454 Chevy swap is as difficult as changing over from a Ford..... :-\

Literally nothing works.  :thumbdown:

Some things to consider;

PTO, Exhaust, Electrical wiring harness, Distributor, Fuel pump, Motor Mounts, Alternator Mounts, Cooling system, accesory drive pulley....Hell the holes in the stringers wont even line up when you get new mounts...I think the only thing that will carry over from the Olds is the carburetor and maybe the alternator.

Its almost like a complete re rig and a lot of work, but IMHO worth it in the end... I am not trying to discourage you from doing it, but do some research first.... :thumbup:

Really hate to see someone jump in balls deep and run out of parts/money before they finish. :banghead:

Oh yeah, pics or it didn't happen.. ;)

GT
Title: Re: 455 swap to 454
Post by: jet boat performance on December 23, 2009, 09:36:32 AM
can i just bolt in 454 mounts? what else do i need to do?

Alot depends on how the Olds is currently mounted and how you wish to install the BBC , actually if you go "R/mount for R/mount" (eg Glenwood for example ) the horizontal stringer holes for the rear feet should  be the same place (depending on drive line length used ) The front mount will be different but with some mill and drill press work can be adapted from the Olds , If you go three point none of it matters you'll need complete center and rear set ups. ( the mounting choice will also dictate drive line length) The Early Short rockwell drive lines are engine specific , however if you currently have a "1310" you can use it with a BBC pto You will need : water inlets , water outlet, exausts, likley a jet oil pan (@8" max depth)  a PTO and mounts . We do these all the time call if you need help Tom

for driveline info : http://www.jetboatperformance.com/index.php?p=drivelineeducation
Title: Re: 455 swap to 454
Post by: Nordie on December 23, 2009, 11:50:14 AM
Tom: lemme see if I got this right, because it made sense to me but to help this guy out....if the olds that's currently in his boat is a 4 point mount set-up he should be able to use the back mount no problems at all correct? Because if I'm not mistaken all bolt patterns are the same in the rear for gm correct? Front one "if a 4 point" can possibly be made to work with some milling and drilling?  We all know that the exhaust and water pump housing will not work, but fortunately they are a dime a dozen....
Title: Re: 455 swap to 454
Post by: crewchief22 on December 23, 2009, 12:28:33 PM
Because if I'm not mistaken all bolt patterns are the same in the rear for gm correct?

Chevrolet bell housing pattern is different than "Buick,Olds,Pontiac".  Similar but different.
Title: Re: 455 swap to 454
Post by: Nordie on December 23, 2009, 02:24:40 PM
I guess I'm picturing a transmission and how they bolt up....
Title: Re: 455 swap to 454
Post by: GT Jets on December 23, 2009, 02:39:01 PM
I guess I'm picturing a transmission and how they bolt up....

An automatic trans is the same way...Olds Specific Vs. Chevy Specific...Manual trans = Borg Warner or corporate :thumbup:

Different animals... ;)  If you look at them on the ground, a 455 Oldsmobubble looks a lot like a Ferd Bell housing... :-\

GT
Title: Re: 455 swap to 454
Post by: Nordie on December 23, 2009, 02:41:26 PM
no wonder why i never liked olds....
Title: Re: 455 swap to 454
Post by: GT Jets on December 23, 2009, 02:41:47 PM
no wonder why i never liked olds....


LOL
Title: Re: 455 swap to 454
Post by: jet boat performance on December 23, 2009, 08:13:09 PM
Tom: lemme see if I got this right, because it made sense to me but to help this guy out....if the olds that's currently in his boat is a 4 point mount set-up he should be able to use the back mount no problems at all correct? Because if I'm not mistaken all bolt patterns are the same in the rear for gm correct? Front one "if a 4 point" can possibly be made to work with some milling and drilling?  We all know that the exhaust and water pump housing will not work, but fortunately they are a dime a dozen....

Nordie sorry to confuse I'll try to re explain and make better sense : the bolt patterns on the back of the block for Olds and Chevy are not  (as said) the same However because on both engines the "center of the crank" as well as the proximity of the crank flange as related to the bell hsg mounting surface are the same , the mount feet only (assuming we go Mount for mount , same brand) will end up in the same place, one would still need a BBC specific bell hsg ,just saves having "siamesed stringer holes" hope this makes better sense ... on a different note ironically BBC and BBf rear mount share two of the exact same bolt holes and a BBF b'hsg can actually work on a BBC with some work (but not the other way due to ford low mt starter mounting styles Tom 
Title: Re: 455 swap to 454
Post by: jet fever on December 24, 2009, 03:25:09 AM
thanx guys. I have a complete 454 in my tahiti "runs great" but my garage is full it sounds like and easy 1000 bucks @ a shop. damnit. :banghead:
Title: Re: 455 swap to 454
Post by: jet boat performance on December 24, 2009, 10:16:32 AM
thanx guys. I have a complete 454 in my tahiti "runs great" but my garage is full it sounds like and easy 1000 bucks @ a shop. damnit. :banghead:

Your right ,On average useing a combo of new and used pieces one can figure about $1500 IF you have a "running" motor to go in Tom
Title: Re: 455 swap to 454
Post by: Beaveretriever on December 24, 2009, 11:23:28 AM
its a MFer, get some friends and have at it. here is a link of how we did it on my old boat, RedSnapperSlappers new boat


http://www.socaljetboats.com/index.php?topic=4399.0
SMFPacks CMS 1.0.3 © 2026