'90 454 from 3/4 Ton Suburban

[sjvcon]

\'90 454 from 3/4 Ton Suburban

Does anyone know if the 454 from a '90 3/4 ton Sub is a 2 or 4 Bolt? I am looking at buying one to swap into my '79 K-20 Sub, and was just curious...

 

[rcamacho]

Re: \'90 454 from 3/4 Ton Suburban

You can check the casting numbers at http://www.mortec.com/location.htm. Always best to pull the pan and check if it's an option.

 

[sjvcon]

Re: \'90 454 from 3/4 Ton Suburban

Problem is that it is in a vehicle about 100 miles from me ... running vehicle. The price is right, but just was curious. Even if it is a two bolt, it wouldn't be bad with ARP studs, but I'd rather have a 4-bolt. I thought someone may know based on the year and model what was put in ... anyone /forums/images/graemlins/confused.gif

 

[diesel4me]

Re: \'90 454 from 3/4 Ton Suburban

If it was cheap enough I'd buy it regardless--even if you find its a 2 bolt main and dont want it,chances are you could re-sell it at a profit to someone who doesnt care.Big Blocks are like money in the bank around here--I know of one guy who sold a bone stock 396 from a rotted chevelle he got for 100 bucks through his scrap car removal business--he spent about 1 hour making it start and run,and by the end of the day he was fighting off 2 people who wanted to buy it for 500 bucks!. /forums/images/graemlins/eek.gif /forums/images/graemlins/crazy.gif

 

[ratzila]

Re: \'90 454 from 3/4 Ton Suburban

The 350 that we pulled out my 90 3/4 burb ended up being a 4 bolt main. I don't know about the 454's they put in them.
The 454 I had swapped in is a 2 bolt main & haven't had any major problems yet /forums/images/graemlins/peace.gif

 

[rcamacho]

Re: \'90 454 from 3/4 Ton Suburban

2 bolt mains are fine unless you plan on revving over 6K. If so, you probably have the budget for a 4 bolt block or installing aftermarket billet steel 4 bolt caps. A 2 bolt block usually has enough material in the mains for installing aftermarket 4 bolt caps. Line hone will be required though.

 

[bigred81]

Re: \'90 454 from 3/4 Ton Suburban

The 454's from 88-90 which is the old mark VI big block were all changed to 4 bolt mains in those years. All the big blocks from 1988-2000 come from the factory with 4 bolt mains.

bigred81

 

[thor]

Re: \'90 454 from 3/4 Ton Suburban

[ QUOTE ]
The 454's from 88-90 which is the old mark VI big block were all changed to 4 bolt mains in those years. All the big blocks from 1988-2000 come from the factory with 4 bolt mains.

[/ QUOTE ]
I'd bet against you there, my 89 C3500 has a 454 MK-IV, 2 bolt (original engine).
All gen 5 (91-95) and gen 6 (96 up) have 4 bolt mains.

 

[fortcollinsram]

Re: \'90 454 from 3/4 Ton Suburban

1990 was the last year (I think, or was is 1991?) for the MKIV engine. I could be either a 2- or 4-bolt main. I know for sure 1992 came with a GenV motor that lasted until ~1995 and then they came with the Gen VI. Both GenV and Gen VI BBC's are 4-bolt mains. I have a GenV that is from a 1992 K3500. The best thing to do is find the casting number on the heads and on the block and see what creature you have. You probably have peanut-port heads and a 2-bolt main; thats my guess. GM was fond of using the peanut port heads on BBC's in truck applications.

Either way, if the price is rigt, get it. You won't ahve any problems with a 2-bolt main unless you are wrapping it to 6000+ rpm constantly and making 500+ HP. And you could always have 4-bolt splayed mains added if you did want a ridiculous motor. the aftermarket splyed mains would be stronger than the factory 4-bolt stuff anyhow. There is a machine shop here in town that is doing 4-olt splayed mains on a SBC I am building as we speak for $350 including billet bearing caps and I don't think it could be much for for BBC stuff..

Chris

 

[sjvcon]

Re: \'90 454 from 3/4 Ton Suburban

Well, I would be getting a whole running donor 'burb (2wd) for about $1500, which is not too bad out here. I need all the smog garbage due to state laws. Otherwise I would just buy a motor from Chevy. It will need a rebuild, so doing the splayed caps wouldn't be too hard I guess.