lopoetve

Ok. Researching my pipe dream...

The 502 I'm looking at is carbed, my car is a TPI. What is the best solution for this problem? Computer controlled carb, or convert the 502 to FI?

I've heard that the hookers are a bizotch, where can I get custom headers and (approx) how much?

What kind of ECM/PROM modding am I going to have to have done?

Is the T56 a straight up bolt on, or do I have to mod the tranny to get it to work?

anything else I should know about?


thanks!

RB83L69

1. Depends on emissions laws in your locale... a carb will sure cost alot less and make more power more easily, but may be impossible to get past tech. A CC carb is out of the question as far as getting your money's worth using it; very difficult to re-tune, and not really enough flow capacity. Check your local regulations.

2. Yes. Lots of $$$ by the time you get them to work. But they do fit fairly OK, big block exhaust by nature is an easier fit into most chassis.

3. See Question 1.

4. Depends on the T56. If you use a LT1 F-body one, it's more or less a straight bolt-up. I don't know for sure what flywheel you'd have to use; I'd assume you'd have to get one of those Centerforce ones for the T-56 —> 2-piece RMS combo, and have it "unbalanced". That's just a wild guess though.

5. Probably.

lopoetve

Ok... an update.

1. Found me a EFI 502. That solves that problem.

2. So the hookers are lots of $$$ by the time they work, or the custom headers?

3. Check. Do I need a whole new ECM or just a custom PROM?

4. Ok.

5.

And now, the new one:
My dash is electronic (speedo, etc), will this require new VSS, etc?

AlkyIROC

How are you going to use the 502? That will determine what parts you need.

2:

A street engine can be the easiest swap. The hooker BBC swap headers are 1 7/8" primary tubes and will work well on a street 502. I doubt they could get exhaust out quick enough from a 502 above 5500 rpm.

There are a couple of other bigger BBC/thirdgen header options out there. Lemons Headers and Sandersons come to mind but expect to pay between $700-$1000 for a set since these are not considered street headers.

3:

If you go to EFI on the BBC, you'll probably need a new ECM and it should come with the EFI system anyway.

5:

It's just another BBC swap. Throw a stroker crank into the 502 and make a 540.

lopoetve

Well, after discussing it here, and with some other people, I've made the following conclusion, and it'll take 2 cars!

1: LIZ (Lynelle Is Zippy, Lynelle being my GF/Fiance that borrows my car)

Caddy 500 powered Firebird, Tremac TKO or T56 manual tranny, aiming for 430/600 at the crank, expect to spend 6-6.5k.

2. TIZ (Turbo IROC-Z)

An IROC-Z powered by the Turbo6 from the TTA or GNX, aiming for 400/580 or so, with the TH200 auto tranny.

heh. Two fast suckers, one a big block, the other a sleeper

Sound good ?

87RS402

You'd be out cheaper and easier if you scrap the idea of a 500 cad right now. B-O-P bellhousing pattern, exhaust header conversion issues, width and parts cost issues make that idea expensive and hard.

You have to have a ton of stuff custom fabricated to do it. Not saying it can't be done, just that it would cost you more money for less power than you could get from a BBC.

AlkyIROC

http://www.cad500parts.com/ has everything you need for a Caddy engine. A complete engine "starts" at around $5k. That's not going to including all the changes you'll need to do to drop it into a third gen. Don't expect a factory Caddy engine to survive. They don't like going above 5000 rpm for very long before the valve train self destructs.

Headers are not a problem with a Caddy. You buy the appropriate BBC headers for the car, ie. Hooker Supercomp, cut off the mounting flange and weld on the Caddy mounting flange. BBC and Caddy have the same spacing of the exhaust ports. They just use a different bolt pattern to attach the exhaust manifolds.

I don't think you're going to find a Tremac TKO or T56 with the BOP bolt pattern although adaptor plates should be available.

Going the turbo route can get just as expensive. To produce lots of HP from boost you'll need a huge aftercooler. I think the aftercoolers start at around $2000. There was a Buick T-type with a V6 in Mission BC this supper running in Super Stock. It ran very low 8's, shattering the old record by almost 1/2 second and before melting the engine.

You can build a 454 BBC with the same amount of power for a lot less than buying a 502/502 package.

five7kid

iTrader: (14)

BBC in a 3rd gen and Colorado Air Care are incompatible. They will open the hood, and as soon as they do that, you're dead.

If you want to register this car in Colorado, your only hope is to do so with an address outside the CAC jurisdiction. If that's already the case, congratulations (at least until they decide to require the entire state to undergo inspection/testing).

RoadRacer

As if the install of a BBC isn't bad enough, the emmisions checks (bi-annually here in CA) will get you. Some people have found that they can go to a "special" SMOG check station and get a "custom" test that will magically make their car pass, but going rate is about $500. Even if you go that route, the cops can cite you for "modified emmisions system" and make you go to the "State Referee" to get a SMOG check. The Referee does NOT offer the "special" inspection . . . at ANY cost. If you fail a Referee inspection, your vehicle can get labeled a "gross polluter" requiring annual SMOG checks at a Referee station ONLY!

Tell me again why we go through this ? ? ?

lopoetve

Ok, just got back. My Bird should be fully running again by the end of the week (clutch, tune-up, few minor issues).

1. From what I was told, getting things to match up with the 500 would be pretty easy. ~Supposedly~ it even bolts up to the T56 with only minor changes.

This was from the logic that the 502, which attaches to the T56, which is a 454 bellhousing bolt pattern, which is the same as the one used on the TH400, which will fit a caddy 500, therefore if a=b=c=d, a=d. Right?

2. I plan on staying below 5000 RPM, I'd get a new rearend for it to stay there. I know it's expensive, and I was planning on cad500parts. As for the price... I wanna be an 8.2L Firebird :hail: so that won't be a concern (mucho saving...) But, I might get the 454...

3. CAC is a pain. Hell, my 305 and CAC are incompatible. But... supposedly since it started with a V8, I can pay extra for "Hot-Rod Status" and not have to worry about the emissions. I've got to research that though.

4. We go through it to keep cars like the Thirdgen on the road and out of the crusher.

Or there always is another way... Get an Iron Duke 4 to drop in for the test. Should pass fine, then swap it back out with the BB!

lopoetve

Nice first car! Lucky bastard... I'm in Boulder/Louisville, so I definately have to worry about CAC. I can feel the hatred from the greens every time I drive to boulder...

87RS402

Wrong, the TH400 bolt pattern is different for Buicks, Olds, and Pontiacs which are the same as Cads. That info is part of HotRodding 101. There are adapters that will change the B-O-P patternt to a standard Chev pattern but they add lenght to the bellhousing and in turn change the lenght of input shaft needed so the tip isn't floating in space.

Cad 500's are slightly wider than a std BBC so don't expect headers that fit badly already to fit well once you change the flange.

Again, easier and cheaper ways to be different.

lopoetve

Like I said, I'm gathering research. Thanks for clarifying that deal with the bolt pattern.

I'm also new at this, and this plan is over a year away.

I know its crazy and expensive, but that's why I'm helping a friend drop a 350 into a 280Z. We're like that

If I can't get headers for it that fit, I'll use the massive machine shop here on campus (yea 20mil in taxpayer dollars down the drain) to make some. The guys here have custom built several engines (both piston and turbine), a simple set of headers shouldn't be too hard.

For comparison's sake, how much is a warmed over 454 going to run me, and how much simpler would it really be? Aren't they tons heavier?

87RS402

the weight difference between the two assuming alum intake and waterpump on the BBC is about 60-70 lbs, no difference if you use alum heads on the BBC.

Air_Adam

I've heard something about early 4th gen Corvette (84-89) 6 speed trannys being a pretty easy fit into the car.. i dunno for sure 'cuz i have never seen it myself, but you may wanna look into it.

lopoetve

I'll keep that in mind.