'85 454ci ?'s

[RAWPWR3]

Hey guys, not long ago i picked up an '85 suburban with a 454 in it for a steal. The motor was freshly rebuilt and was bored 30 over, has an "rv" cam, an alluminum intake, longtubes, full exhaust, and a nice th400 to back it up. Im trying to find out more info on the specifics of the rebuild from the previous owner, but for now, does anyone know what the specs were on one of these back in the awsome eighties? For example stuff like comp. ratio, i know they had alot of emissions stuff on it back then, but its a start. Im hopefully gonna pull it out and put it in a 66 nova or something like that. Thanks

[Hot Black Trans-Am]

If he bored it I doubt he kept the stock compression. I love big blocks.

[RAWPWR3]

Yeah me too man, thats why i couldnt pass it up. I like small blocks and all, but it seems like you see alot more of those out there than big blocks. I know the comp ratio changed when it was bored out, but i was just trying to find some factory specs. Just how stout are big blocks? Whenever i find out exactly what was done to it by the previous owner, i wanna either spray it or strap a blower on top of it. Also can you or anyone else recomend a nice carb to put on there for now? Its got the factory quadrajet, but i dont think the secondaries are opening up, cause i tested the little vaccum diaphram and it didnt hold vaccum.

[Firebirdjones]

I have a 79 454 1 ton pickup that I use to tow with and even race for giggles on occasion when the car breaks

They didn't change much from 79 and on into the 80's. Compression and camshafts stayed virtually the same.

Mine is stock with 8.5:1 compression. Yours should be the same if stock.

But since you mentioned someone has been through the motor it could be virtually anything.

As far as emissions,,,thats a grey area on these trucks not many are aware of today. Back when cat converters were in full swing,,,these bigblock trucks didn't get them as long as GVW was over 8,000 lbs. which was basically everything from "Heavy Half" and up, which would include 3/4 and 1 ton stuff.

This was back in the late 70's and early 80's,,,not sure when the law changed but back then thats how these trucks avoided the smog police.

The only emission my truck had was the smog pump and evap cannister....no cats at all.

I removed what little smog the factory had on it and did a few simple mods,,,even with the whimpy compression it's a decent runner.

With a performer intake and matching performer camshaft,,,small tube (for engine size) hooker headers and 3 inch exhaust,,,a tweaked distributor curve and a fuel curve using the stock Q-jet dialed in with a wideband I have this 5,500 lbs. tank running 14.70's at 94 mph. With stock 400 turbo and stock 3.73 gears. Not blistering fast but for a big (over 2 ton) truck shaped like a brick it's enough to raise a few eyebrows from mustang owners.
This engine in a more aero friendly body that weighs a typical 3,400 lbs. would be an easy low 13 second ride.
Not bad for a low compression motor with stock short block and peanut port heads.

I would stick with the Q-jet,,,if all thats wrong is the vacuum pulloff,,,that could be quickly fixed for a cheap $10. As far as the rest of the motor goes,,,it's hard to say since someones been through it. Have some fun with it.

[matchbox]

Good buy. Find out if it has rectangle or oval port heads. If he punched it 0.30 over then now it should be at about 10:1. either way good buy. Just remember BB aren't good for High RPM's. I have 3 BB's on stands that are virgin motors.NOT FOR SALE. They are hard to find.

[RATCHETMASTER]

This engine may have what are often called "peanut port" heads with very small oval intake ports. Check the casting #s. IF they are, they are not good for over 4500 rpms. YOu will want to replace them with another set with the regular oval port heads. The engine otherwise should be good to go but will have lower compression.
You can use 1970 or earlier heads which will have smaller combustion chambers that will increase the compression but these are called "closed chamber" and are not the best when trying to pass emission specs. The 71s have open chambers and breath better for smog but you lose some compression.

Overall a good find if the price was right. And scrap metal is paying really well now too for the rest of the truck. You may be able to sell some of the parts before recycling it but the rest should bring about $250 in metal.

[RAWPWR3]

Thanks alot to everyone who chimed in on this thread, thats exactly the kind of info i was looking for, it has all been very helpful! Thats pretty impresive firebirdjones, obviously these motors have alot of potential. When you say smog pump, are you reffering to the air pump? If so, mine isnt equipped with one, but it does have an egr valve on the intake and the charcoal canister down by the driver front fender. My buddy told me that there is a port made into the head that feeds the egr, unlike our cars that has it come up from the exhaust manifold. So would the only way to delete this be by replacing the heads or can i take the egr valve out and just put a block off plate where it was?

Ill be going home again this weekend and ill check out what the casting #'s on the heads are, and ill let you guys know what they are. Thanks for bringing that to my attention matchbox and ratchetmaster. I still havent been able to get in touch with the previous owner about whats been done to the motor, but its running way better since we got it. My father knows his way around carbs, and when we looked at it, on one side the idle screw was all the way in, and on the other it was all the way out. And there was no vaccum line going to the vacc. advance on the distributor. So just those little things made a world of difference and it got me excited to find out what else i can do with it. Also, where should the vaccum advance line from the distributor be fed from, the carb or the intake manifold? Its got all kinds of plugged off vaccum lines so i gotta go through it and see whats not needed to clean it up a bit.

Its funny you should bring up scrap metal ratchetmaster, cause thats all the body is good for pretty much! It was in key west all its life and neglected by the owner, but since the motor was fresh i couldnt pass it up. It amazed me cause there isnt even a sign of seepage from oil anywhere on the motor, and the comp. was good, it doesnt burn oil, and it starts right up! Totally unexpected for me from an "antiquated" motor. Sorry about the essay guys, and thanks again for all youre help. Heres a picture for youre viewing pleasure...

[Firebirdjones]

Sorry for the late reply,,,just moved to Arizona.

Yes you can simply remove the EGR and block it off,,,,or go with another intake manifold without the EGR,,,thats what I did on mine,,,,Just a basic Edelbrock performer intake is all that was needed on mine to make good off idle power along with their matching camshaft,,,which is what I consider tiny for a motor of this size,,,but it works good.

Combined with the peanut port heads it makes gobs of low end grunt and still pulls strong to 5,500 rpms. I was only after more pulling power to tote around my trailer,,,,,,the ET's just came as a result by accident really

Nothing wrong with the peanut port heads by the way. Lingenfelter proved that many years ago,,,and stuck them on a 496 to make nearly 600 HP on pump gas with over 650 ft lbs. of torque to boot,,,stuck it in his truck to tow the race car with.
Hope you have some fun with it.

[RATCHETMASTER]

With a performer intake and matching performer camshaft,,,small tube (for engine size) hooker headers and 3 inch exhaust,,,a tweaked distributor curve and a fuel curve using the stock Q-jet dialed in with a wideband I have this 5,500 lbs. tank running 14.70's at 94 mph. With stock 400 turbo and stock 3.73 gears. Not blistering fast but for a big (over 2 ton) truck shaped like a brick it's enough to raise a few eyebrows from mustang owners.
This engine in a more aero friendly body that weighs a typical 3,400 lbs. would be an easy low 13 second ride.
Not bad for a low compression motor with stock short block and peanut port heads.

WOW!! I somehow missed this part of your post when I read through the posts! THAT is impressive. That et is fantastic considering the weight of that beast!
The gears definitely help though. That is one thing many car enthusiasts miss . . . they build their killer motor, and have 273 gears!! lol!

So you did no porting on the heads? I am interested in the other info you posted about the 600 hp motor built. Can you direct me to an article of that build? I can't imagine him using these heads without porting them. I mean you can only get so much air through those tinny ports.

ttyl
Rat

[Firebirdjones]

Thanks, actually the engine in my truck has never been apart and has 78,000 miles. I didn't do anything to the heads other than install valve springs for the performer camshaft and new roller rockers.
The MPH is a little weak for the ET it runs,,,,guess the motor is light in the HP department but it makes alot of grunt,,,,great for towing which is what I wanted really.

As far as Lingenfelter experimenting with peanut port heads,,,,I'll dig it up. Not sure if it's on his website or any other. He did a big article on it years back.

From what I remember he did port on the heads,,,mainly in the pocket areas behind the valves and short turn radius to accomodate the larger valves he installed. Stock were 2.06 and 1.72 and he went with 2.19 and 1.88's,,,,same as what would be in some of the factory square port heads.

If I ever tear this old truck motor down for a rebuild I would probably shoot for the Merlin oval port heads that mimic the passenger car heads but raise the exhaust ports slightly,,,and drop a 4.250 crank in for a 496. Should tow the trailer nicely

[RAWPWR3]

Sorry for the late reply,,,just moved to Arizona.

Dont worry about it man, and congrats on the the move. Thanks again for all the help and info. Im currently going through the hot rod courses at school, and our instructor is a big big block nut, so im picking at his head for all the info i can get. Although he used to work for holley carbs, so hes partial to them and hes beginning to convince me to slap a big double pumper on there! And now that i know the difference between intake manifolds, i was thinking of getting a dual plane to aid in the big blocks' low end grunt. But all in due time i guess...

[Doug_J]

A good factory set of iron heads for a built BBC would be a set with the last 3 numbers of the casting ending in 781 or 049, my engine builder told me about this. I have a 454 bord 40 over, all im trying to do is find a nice car to put it in.