i got an 87 firebird that curently has the 2.8 v6 and auto trans. a guy i know just parted out his old 82 chevy plow truck and wants 600 bucks for the 454 and th400. i don't want an automatic transmission so i started looking and found a t56 manual trans from 4th gen camaro lt1 car. i plan to drive the car like it is this summer and when i take it off the road for the winter i will start the build. rite now i am just gathering parts and info.i know that engine and trans combo will fit but is it possible to keep the air conditioning. i am thinking the passenger side valve cover may hit the heat/AC hvac box whatever its called on the passenger side of the firewall. five7kid suggested that a fourth gen hvac system may work but didn't know for sure. has anyone else done a big block swap and kept the ac.

i know i need to still get a fly wheel, pedal assembly, motor mounts, headers(i was thinking of trying those patriot ones), and ignition system. any suggestion what i should get and where to get it.also are their any other parts i still need to get.

 

If you use the '91-'95 valve covers, they will, barely, clear the a/c box. I have a pair if you can't find any locally.
I'd take the valve covers off entirely for the installation, then try to test fit the ones you already have.
You will need Moroso solid motor mounts to be sure the engine doesn't rock over and slam into the a/c box. This is what I used with my test fit. You'll need both of these Moroso part numbers: 62510 and 62610.

 

are the 91-95 valve covers shorter? also this is a street car not race only so wont the solid motor mounts make the car shake or something? and are the 4th gen A/C box's smaller? if so will they in combination with the 91-95 valve covers give me enough clearance?

 

Until '91, the valve covers were stamped steel. I didn't have any, or I would've tried them. But since I didn't, I can't tell you they fit. They might.
I did try the cast aluminum version, and I can tell you they do fit.
Solid mounts aren't bad unless your engine is WAY out of balance. You could try polyurethane mounts and then add a torque-over limiting strap of some sort. That might be more your style.
I doubt if the 4th gen box will even fit, I've never even heard of anyone trying it, so I can't comment.
I was doing this with my '84 Trans Am, so that's the a/c box I used.

 

what is a torque-over limiting strap?

also is there a difference between the 84 and 87 A/C box?
thanx for the info

 

I don't think there's any significant difference between '84 and '87
If you ever watch a rubber-mounted engine, you'll see the rubber lets the engine twist over more as you rev the engine. The thing is, this would let the passenger side valve cover hit and break the a/c box.
Now, if you build it and see the valve cover is say 3/16" from hitting the a/c bok, you could fab up some sort of strap or chain that has say 1/8" of free play in it.
Things like this have been done for decades, but there are no kits. Moroso makes a solid link for fox mustangs, but that's not what you want.
Anyway, the engine can still move around at cruise, but when you floor it, the chain or strap would keep the valve cover from hitting the a/c box.

 

None. They maintained the same box over the 3rd gen years.

 

you can purchase engine torque dampers from pretty much any aftermarket company. alot of tuner mags have ads for them, but im sure March systems would have one, its basically just a hood strut/strong arm. you could make one out of a high pressure unit that is damping on the opposite side of the rotation. i believe you would need to attach it too the passenger side of the engine and body.

 

those might be great for wussy V6s, but this is a 454, it'd need at least 2, and even then, they still aren't absolute like a chain.

 

Refreshing my memory with research, it appears the members that have used it put the 4th gen guts in the 3rd gen box.

You may have to reshape the box.

 

how hard would that be to do?

and i am glad i didnt buy the 82 454 from my buddy yet cuz i just found a 98 vortech 454 which comes with the ecm and wiring harness for 1200 bucks. its twice as much money as the 82 but it is a newer engine with less miles. which one do you guys think is the better engine

 

the '98 is also gonna have much much less bore wear. Plus the slightly better heads.

 

will the 98 fit the same as the 82around the valve covers?
and how are the heads better? is that what the vortech means?
will the t56 bolt to the 98 the same?
how hard do you think it will be to wire that computer and harness it my car? thanx

 

the big block vortec heads are just large ovals with modern chambers, which is still better than peanut ports with smog chambers
I don't have the answers to your other questions, sorry.

 

has anyone used a vortech 454 in a third gen before? i know the 4th gen like the 82 are a common engine to swap in. and that there was something people don't like about the 5th gen 454's. i think what i am trying to say is do you know if the vortech 454's are a good engine to use in a third gen. are there any issues with them. thanx

 

You'll probably need a custom hood to clear that bizarre intake manifold. And why bother, when the traditional intakes bolt right on to the Vortec heads? the 8100 takes special intakes, but those weren't out yet in '98.

 

what do you mean by 8100?
and what would be good intake manifold to use. i would like to keep the fuel injection.

 

will this pass emissions if i keep all sensors and stuff on the engine?
im not really concerned if the car is technically legal or not i do my own inspections i am just curious.

 

Around '00 or '01, the Vortec 7400 got replaced by the Vortec 8100. It went to a tall deck, a 4.370" stroke, and replicated-port heads. It looks like a rat, but nothing interchanges. It's not a 502, which you could use.

 

alright now you confused me. what exactly are you trying to say. the 98 won't work or do i need something from an 8100?

 

Sorry, didn't mean to confuse you. Probably shouldn't've even mentioned the 8100. Mostly did it for others who will later be reading your thread. Soldier on, you're doing fine.

 

do i still need to get a new intake? if so what would be a good one to use. i would like to use a stock hood. and fuel injection.also what kind of fly wheel do i need to mate the t56 to the vortec 454?
also my car is an automatic rite now so for the clutch/brake pedal assembly should i get one from a third or fourth gen? i was thinking fourth cuz the transmission came from a fourth gen.

 

I'm fairly certain there's NO way to fit an injected rat under a stock hood.
Any '65-'98 bBC large oval port intake should bolt right on to your '98 Vortec 454 heads, but I think all of them will require a cowl hood or some such. I do have an idea, but it hasn't been tried. Use the lower intake from an older Edelbrock dual-quad with the plenum from an HSR, but then you need to fab a custom adapter plate, and a custom water neck.

 

whats the smallest hood i could run? would a 2 or 3 inch be enough clearance?

and with your idea by dual quad do you mean dual 4 barrel intake? and what do you mean by hsr?

 

the HSR is the Weiand stealth Ram for the SBC. Weiand is owned by Holley, so everyone here calls it the HSR.
This odd fusion of Weiand plenum and Edelbrock manifold would be shorter than puttang ANY air cleaner atop ANY carb, and might fit under a stock hood. The plenum would be good past 400 horses, but you're still looking at custom fuel rails, and having the manifold modified to accept injectors.
If you want EFI and a stock hood, I don't see any other way.

 

so i guess i'll start looking for a hood. do you think one of them ram air 1 or 2 hoods will clear the intake? or should i just go with a basic 2 or 3 inch cowl hood.

this aint the 454 i am getting but it is a 98 vortec 454



the valve covers look about the same size as the 82's so they mite clear the heater/ac box.
as far as hood clearance goes it looks like the ac pump will be more of a problem than the intake. is there any way to move it?

 

also my car is an automatic rite now so for the clutch/brake pedal assembly should i get one from a third or fourth gen?

If you get the fourth gen peddle assembly you will have to cut off the gas peddle near the brake mount as the floor pans are different in that area. the clutch and brake peddles bolt up just fine after that.

 

I thought the intake was higher than that, in relation to the valve covers. But after studying your pics, I went and found some others, and my gut feeling is that the stock Vortec truck intake might fit under a stock Camaro hood IF you change the accessory brackets.
I believe the lowest brackets are the '68-'74 'vette, check around, maybe Year One or Classic Industries or one of the other restoration "houses" offers them.
If you can't get the stock hood to close on that, then pick whatever hood you most like the looks of.
I'm doing a thread on fitting a '94 Suburban oil pan, take a look before deciding which pan to use, as the Gen 5/6 "car" pan linked to within would also fit your '98 Vortec 454.

 

so if it will clear camaro hood it should also clear a firebird hood.
will there be any other clearance issues on the sides if i use a 68- 64 vette brackets? also would that be a serpentine belt setup?
got a link to the pan thread.

so if i get a pedal assembly from a fourth gen it will have all three pedals and i just have to cut the gas off?

 

Third gen. Firebird hoods have less front clearance than third gen. Camaro hoods, look at how the 'bird nose drops off more. That's why most BBC third gens are camaros, not Firebirds. It's not because there are more Camaros out there, (there are), but the Camaro hood clears better on the third gens.
It's the same with 'vettes, the '68-'74 hoods drop off more than the '65-'67.
NO '64 vettes came with BBCs, because until '65, there was no production BBC. The 409 wasn't really a BBC, and it was never offered in 'vettes. Also, due to the lower production, the '65-'67 brackets are rare.

 

 

that is correct. here in the austin area the fourth gen stick cars are a dime a dozen.

 

yeah sorry that was a typo i meant 68-74.
would march or someone else make an aftermarket bracket kit that would fit?

fourth gens with a stick aren't real common around here but i know where the one i got the transmission from is. and i'll go back over some time and get the pedals.

 

March could have something helpful, I wouldn't know, I haven't tried their stuff, don't have their catalog. Their stuff is good, but so far I've always found cheaper alternatives with acceptable quality.

 

can you explain what hydroboost brakes are. i was told the 98 truck my engine is from had hydroboost brakes. is that something i should get off of it.

 

With gasoline engines, there's a throttle that controls engine speed, it's connected to your right foot. Having that throttle means vacuum, so the power brakes can be boosted by that.
But with diesel, there is no throttle and no vacuum. your right foot is connected to the fuel delivery, and that's what controls engine speed.
So on diesels, they created hydroboost, where the power steering pump also provides power assist for the brakes. The fluid makes it a hydraulic system.
You have about 7 options.
(1) Manual brakes (2) Adapt the hydroboost (3) Install a vacuum pump. Probably electric driven. (4) Fred Flintstone braking (5) parachute (6) something I haven't even dreamed of (7) some combination of these

 

ok so the 98 454 truck won't have it then. but that does sound like an interesting upgrade. from what i am seeing they are smaller than the vacuum brake boosters. so that would clear up room under the hood. are there any advantages to running that kind of brake setup.and how hard do you think it would be to convert to it.

 

When playing with brake boosters, it can be surprisingly difficult to change the length of the pushrod that connects to the pedal. It's heavy, it robs power, it's something else to go wrong.

 

what do you mean by this. i have been reading that people have done this using the booster from an astro van and master cylinder from a fourth gen. why would i have to change the push rod?
also would doing it with the astro booster work with 4th gen pedals?

 

No Astro ever had hydroboost.

 

Check again.
http://www.autopartsgiant.com/parts/...universal:0%29

 

go to this thread
post #47 TB2 says he used the hydroboost from an 94 astro van. he drilled the rivets of the stock booster then bolted the astro booster in place.there was no issues with rod length the diameter was off so he used a bushing and the stock rod worked fine. he also machined down the astro booster to make it fit the third gen master. but i read on another thread that a fourth gen master bolts rite up to an astro brake booster

EDIT: after reading more of that thread it turns out you do have to modify the rod length here is pot 121 from that thread explaining what TB2 did. still doesn't sound to difficult

 

Just to help clear any confusion the 4th gen brake and clutch peddles are exactly the same as third gens save for the pads and attached gas peddle. if someone has adapted the hyroboost to a 3rd gen set then follow thier guide for atachment.

 

Why the hell would GM stick hydroboost on a gasoline engine? That's just stupid beyond belief.
Anyway, when I installed my '94 454 in my '84 Trans Am, I had no trouble with the valve cover being at all close to the vacuum booster.
You're still adding more stuff that can go wrong, and if a weld fails, because most rookie welds do, you could kill someone.

 

first off i aint no rookie welder i have took welding classes and am really good at it besides i would only have to weld one thing the bolt to the rod.also i checked and the 98 silverado 2500 hd that the 454 is coming from does have hydroboost. im not totally sure if im gonna do the hydroboost just an idea. i still need to figure out what else i need to get like the flywheel or i am not sure but is the drive shaft a gonna need to be changed. i was thinking the t56 was a different length then the stock 700r4 if it is should i get the drive shaft from the camaro i got the transmission out of. also the torque arm would need to be swapped too?

 

The nice thing about hydroboost is it works whenever the engine is running, regardless of engine vacuum. Many street/strip racers use it because they can stall up against their brakes and not have to worry about being able to hold the car when vacuum is decreased with the open throttle. While the vacuum system does hold the vacuum for the next braking event, it isn't perfect and can lose vacuum under the stall-up conditions. Hydroboost, however, will maintain the boost function regardless.

As to why the factory would use hydroboost on a gasoline vehicle, I can't answer that. Other than to say the system works very nicely on my '95 turbo diesel 2500 HD.

 

the hydroboost brake conversion can be done with out having to weld any thing. you can cut the rod off the old booster and thread the end. then cut and thread the rod in the new boosterand screw it back together with a threaded adjuster


thats 500+hpta's setup

now back to the 454 t56what would be the easiest way to wire the truck engine into the firebird?
also should i get subframe connectors. does anybody sell them or do i have to make them?
what kind of flywheel is needed to connect the t56 to the 454?
and do i have to replace the radiator?
thanx

 

Wiring: Pretty basic. You can use what the car came with for the most part. Probably the most "difficult" part will be the alternator, since '87 has a different plug than earlier alternators.

Subframe connectors: There are Board sponsors that have them available. UMI, Spohn, Hawks. I've got Spohn on one car and UMI on the other, not to play favs, but I kind of prefer the way the Spohn's came out.

Radiator: If it is in good shape, you may get away with it. Most go with an aftermarket upgrade, though.

Flywheel: Hopefully someone can answer that. Might find someone who knows on the Transmission and Drivetrain forum.

 

Why the hell would GM stick hydroboost on a gasoline engine?


GM used the Hydroboost system in most big block 3500's since 1988

 

i got the engine wiring harness and ecm with 454 so im thinking of trying to use most of that harness. the wires that are on the car now are just about shot i have several electrical shorts that i am gonna try and eliminate with this swap. and i read some where that v6 radiators have the hoses connected to the opposite side than the v8 cars. is that correct

duckmanquacker what about the astro van or the 98 silverado which is a 2500hd

i mite start a thread in the transmission forum later