couple of questions - The 1947 - Present Chevrolet & GMC Truck Message Board Network

DRAGGINCHEVY98 · 04-19-2009, 07:38 PM

ok so ive bought a 72 3/4ton suburban with 402/400 . white/oilve green / green interior. .motor has developed a knock which i think is a main bearing going out. so here my three options right now..
1 rebuild the current motor and freshen the tranny
2 friend of mine has a 454/400 out of a mid 80s crewcab for 800.00 motor has good oil pressure and doesnt smoke
3 been thinking about a 12valve cummins swap .

my plans for the sub is porter built dropmember to lay it out ,typical rot in typical places..ill post some pics soon . thanks for input.

will the 454 swap need a different oil pan or anything special , thats the way im kinda leaning right now...

vectorit · 04-19-2009, 11:15 PM

Build up the 402, and freshen up the trans. I would think the 402 has better heads on it anyway.
But then again I am a guy that prefers originality, and 454's do nothin for me.

Average Joe · 04-20-2009, 12:12 AM

I guess the question I have is how quick do you need this thing back on the road? If its a driver and you need it running like yesterday I'd say 454. It should drop right in with swapping external accessories from your 402. I guess a intake swap might be in order if its EFI? I dont think the oilpan is an issue. It is rear sump right? This option only has the rig down for a weekend. If time is not a factor I would put the 800 you would have spent on the 454 towards a rebuild on the 402. Good luck to ya either way.

Longhorn Man · 04-20-2009, 12:32 AM

Ive never been a fan of the 402, and I am actually considering jerkin mine out for something with enough ass to pull it's own weight.
I say go with the 454... if I'm not mistaken, the fuel injected ones are roller cam too, which makes it WAY better with todays crappy oils.

mr48chev · 04-20-2009, 03:42 AM

Draggin, do what ever makes you happy. If the 454 is in good shape it is probably quicker and less expensive to do the swap than rebuild the 402.

After you have been around this bunch, and it is a great bunch you will find that there are a couple of different ideologies going when it comes to these model of trucks.

There are those of us who change just about everything to make the trucks look and drive the way we want them to an then there are the guys like Vectorit who prefer to keep their trucks stone stock right down to the original air in the tires.

I appreciate a nice original or fully restored to showroom original truck but prefer to modify mine.

You could always buy and install the 454 now and have a nice running truck while taking the original engine and sticking it in the corner to save to see if you want to rebuild it later.

Welcome to the board by the way.

DRAGGINCHEVY98 · 04-20-2009, 09:08 AM

Thanks for the input guys right now it's just a project but I want to be able to use it tow my other projects around without having to start making payment on something new and plus it's a hellva lot cooler than anything new out there. So right now I just need to take my other project to the other coast of Florida for some more work from Jimmys Rod& Customs in edgewater ,fl. And plus I hate having to ask friends to either borrow their truck or have them pull it wherever I may need it to go. So is 800.00 a fair deal for that 454/400 ,it's tbi so ya I would need a intake . I have a holley 600 laying around is that enough carb for that motor. And maybe swap out the cam for a rv cam. I plan on rebuilding the 402 but I need the money for my other project that I'm working on right now and I'm trying not to get sidetracked like I tend to do by picking up other projects. If I had it my way I'd have probally 25 projects laying around but I'm trying to stay on track. Somehow I don't think I'm the only one with this sickness!!!

Skirkpat · 04-20-2009, 09:31 AM

I would swap out the 402, they are alright, but alot more expensive to build than the 454 will be. I would just swap out the 402 intake, and accesories, and have it running in a few days...

mr48chev · 04-20-2009, 10:58 AM

If it's a really good engine that all you have to do is swap intakes if that and go 800 probably isn't out of line. I think rebuilders are in the 4-500 range around here at the moment. Still these days cash green money waved in the hand seems to speak pretty loudly.

04-19-2009, 07:38 PM	#1
DRAGGINCHEVY98 Registered User Join Date: Jan 2008 Location: tampa,fl Posts: 5	couple of questions ok so ive bought a 72 3/4ton suburban with 402/400 . white/oilve green / green interior. .motor has developed a knock which i think is a main bearing going out. so here my three options right now.. 1 rebuild the current motor and freshen the tranny 2 friend of mine has a 454/400 out of a mid 80s crewcab for 800.00 motor has good oil pressure and doesnt smoke 3 been thinking about a 12valve cummins swap . my plans for the sub is porter built dropmember to lay it out ,typical rot in typical places..ill post some pics soon . thanks for input. will the 454 swap need a different oil pan or anything special , thats the way im kinda leaning right now...

04-19-2009, 11:15 PM	#2
vectorit What? Join Date: Jun 2007 Location: Southern California Posts: 7,617	Re: couple of questions Build up the 402, and freshen up the trans. I would think the 402 has better heads on it anyway. But then again I am a guy that prefers originality, and 454's do nothin for me. __________________ Chris 1968 K20 Suburban 1972 K10 LWB PU

04-20-2009, 12:12 AM	#3
Average Joe Registered User Join Date: Feb 2009 Location: Southern Oregon Posts: 1,352	Re: couple of questions I guess the question I have is how quick do you need this thing back on the road? If its a driver and you need it running like yesterday I'd say 454. It should drop right in with swapping external accessories from your 402. I guess a intake swap might be in order if its EFI? I dont think the oilpan is an issue. It is rear sump right? This option only has the rig down for a weekend. If time is not a factor I would put the 800 you would have spent on the 454 towards a rebuild on the 402. Good luck to ya either way.

04-20-2009, 12:32 AM	#4
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	Re: couple of questions Ive never been a fan of the 402, and I am actually considering jerkin mine out for something with enough ass to pull it's own weight. I say go with the 454... if I'm not mistaken, the fuel injected ones are roller cam too, which makes it WAY better with todays crappy oils.

04-20-2009, 03:42 AM	#5
mr48chev Registered User Join Date: Jul 2007 Location: Toppenish, WA Posts: 15,267	Re: couple of questions Draggin, do what ever makes you happy. If the 454 is in good shape it is probably quicker and less expensive to do the swap than rebuild the 402. After you have been around this bunch, and it is a great bunch you will find that there are a couple of different ideologies going when it comes to these model of trucks. There are those of us who change just about everything to make the trucks look and drive the way we want them to an then there are the guys like Vectorit who prefer to keep their trucks stone stock right down to the original air in the tires. I appreciate a nice original or fully restored to showroom original truck but prefer to modify mine. You could always buy and install the 454 now and have a nice running truck while taking the original engine and sticking it in the corner to save to see if you want to rebuild it later. Welcome to the board by the way.

04-20-2009, 09:08 AM	#6
DRAGGINCHEVY98 Registered User Join Date: Jan 2008 Location: tampa,fl Posts: 5	Re: couple of questions Thanks for the input guys right now it's just a project but I want to be able to use it tow my other projects around without having to start making payment on something new and plus it's a hellva lot cooler than anything new out there. So right now I just need to take my other project to the other coast of Florida for some more work from Jimmys Rod& Customs in edgewater ,fl. And plus I hate having to ask friends to either borrow their truck or have them pull it wherever I may need it to go. So is 800.00 a fair deal for that 454/400 ,it's tbi so ya I would need a intake . I have a holley 600 laying around is that enough carb for that motor. And maybe swap out the cam for a rv cam. I plan on rebuilding the 402 but I need the money for my other project that I'm working on right now and I'm trying not to get sidetracked like I tend to do by picking up other projects. If I had it my way I'd have probally 25 projects laying around but I'm trying to stay on track. Somehow I don't think I'm the only one with this sickness!!!

04-20-2009, 09:31 AM	#7
Skirkpat Registered User Join Date: Dec 2008 Location: K.C. Missouri Posts: 1,024	Re: couple of questions I would swap out the 402, they are alright, but alot more expensive to build than the 454 will be. I would just swap out the 402 intake, and accesories, and have it running in a few days...

04-20-2009, 10:58 AM	#8
mr48chev Registered User Join Date: Jul 2007 Location: Toppenish, WA Posts: 15,267	Re: couple of questions If it's a really good engine that all you have to do is swap intakes if that and go 800 probably isn't out of line. I think rebuilders are in the 4-500 range around here at the moment. Still these days cash green money waved in the hand seems to speak pretty loudly.



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