455 bbo swap

[anakputa]

No hood scoop its a direct bolt in, though some of the brackets may need modification unless you get the brackets from a donor car. I would definitely replace the trans. TH350 or have the 2004r rebuilt at a good trans shop to withstand the 455. I had a 79 Cutlass with 70 Toronado 455 and ran a TH350 that I built. You'll have get a crossover pipe for 455 or get the Hooker Headers for exhaust. If I was to do over again I would have went with a 403 direct bolt in..

 

[joe_padavano]

You'll have get a crossover pipe for 455 or get the Hooker Headers for exhaust.

Not sure what you mean by "crossover pipe". If you don't want to run headers, the A-body W/Z manifolds work fine in the G-body. You'll need a double hump crossmember for the trans, however. The 200-4R will only survive in stock form if you drive it as if it had the 307 in it, which kind of defeats the purpose of the engine swap. Either get the 200-4R rebuilt to live behind the 455, or go with a different trans.

 

[anakputa]

You'll have get a crossover pipe for 455 or get the Hooker Headers for exhaust.

Not sure what you mean by "crossover pipe". If you don't want to run headers, the A-body W/Z manifolds work fine in the G-body. You'll need a double hump crossmember for the trans, however. The 200-4R will only survive in stock form if you drive it as if it had the 307 in it, which kind of defeats the purpose of the engine swap. Either get the 200-4R rebuilt to live behind the 455, or go with a different trans.

"Crossover pipe" if you use the stock exhaust. Is the pipe that runs from the left manifold to the right. Unless you have true dual exhaust and the real rare dual exhaust manifolds..I had the hooker headers behind mine..

 

[2fit661ca]

THANKS GUYS!!!! REALLY HELPS ALOT!! and sorry for changing the subject...

 

[olds307 and 403]

The Olds 455 is a torque monster even in low compression form. An Olds 403 will give a lot of passing power and will clear the heater box, even with tall mounts. My mild 403 hasn't killed the modifed but stock clutch/band 2004r. The SBO is one the most reliable engines GM ever made. Everyone skips the Olds 350/403, saying why build these engines over the sbc. You can bolt heads that flow good (Edelbrock RPM) for a small block engine to them. Compare the 455 head flow to BBC head flow, the Olds look pathetic. Of course GM designed peanut/swirl port heads for sbc/bbc for torque. The Olds, Buick, Pontiac or Cadillac v8's would have made much better truck engines period. Big flow numbers(BBC rectangle port heads) with no velocity mean you need a huge cam, convertor and gears to make it streetable, due to lack of torque. Torque is a hard thing to kill on an Olds v8 due to it's design.

 

[joe_padavano]

"Crossover pipe" if you use the stock exhaust. Is the pipe that runs from the left manifold to the right. Unless you have true dual exhaust and the real rare dual exhaust manifolds..I had the hooker headers behind mine..

You mean the "rare" dual exhaust manifolds that were used on every A-body with a BBO and dual exhausts? The ones that Thornton sells repros of?

 

[2fit661ca]

so, the reason i decided to go with the 455 over the 403 is because i've found it easier to find Olds 455s in my area, and i've found it easier to locate parts. as i get the money, i will upgrade the transmission and the rear end, but being as i am still in highschool, and only make $400 every two weeks, i have a limited budget, and i would like to get the car road worthy before i loose access to the highschool shop upon graduation. (the decision to make the upgrade is becuase of everyone's input here) now, another question i have; does anyone know where i can find a heater box that i can drop in my car that is for systems w/o a/c? if you do, will this box clear the deck/heads of the 455? THANX! :?

 

[Blake442]

The heater box from any '78-'88 non a/c car will work, but there are a few specific pieces for each brand so finding one out of another Olds will be the easiest as far as getting what you need, unfortunately not a lot of Olds's received the non a/c treatment, making the Olds specific parts hard to find.

I have a non a/c set up in my 442.
Here's my set up...

I had to notch it for clearance because I'm running tall valve covers...

88hurstolds runs stock valve covers and I don't think he had to modify it at all...

 

[2fit661ca]

Awesome, thanx. that's a beautiful engine, by the way. 😀

 

[joe_padavano]

so, the reason i decided to go with the 455 over the 403 is because i've found it easier to find Olds 455s in my area

Yes, there were a lot more 455s made than 403s. 455 production covered 1968-1976. 403s were only made from 1977-79.