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Discussion Starter #1
So who's been there done that? Anybody?

What is involved besides engine and computer?
Guess I should say...96 caprice w/4.3L and a
96 Roadmaster 5.7L.

If you want to know why, I got the car cheep because
it had the 4.3 in it, but it only had 43,000 miles on it
and it's RUST FREE.

I can get a 96 Roadmaster 5.7 with 50,000 miles on
it for $650. Also I can get a 95 FIRE bird LT1 cheep
that had a slight engine fire. :rolleyes: With that said
would it be worth the trouble to put the aluminum heads
on the roadmaster engine? Any gain?
Were the cams the same?

I am planning on getting both engines and this winter
doing a 383 / 388 depending on bore with the fire bird
engine. May also do the 6-speed thing at the same time
(still collecting parts).
 

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No gain from alum. head, besides weight. Cam in the F-Bird engine will be a little doggy in the low RPM range as it is cammed for a lighter car.

I've never done the swap, but it's shouldn't be all that much. As you said, the ECM & the engine it's self..not sure about the harness, but I believe the engines are about the same size on the outside so even if you had to add a little here & there it should be no big problem.
 

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Discussion Starter #3
That's what I figured.
Thanks for the reply.:smile:
 

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Be a VERY direct swap.

There is some chance your car has a 7.5" axle, if it does you will want to get a 8.5" to put in it. That was standard in the LT1 cars.

Use the injectors from the LT1 they are 24lbs the L99 got 19lbs.

The pcm is the same part number just the tuning is different. The Roadmaster pcm might pose a few nagging little troubles like speedo being off depending on gear and tire options.

Harnesses are indeed the same.


Stock aluminum heads would be a wasted effort.

One very common mistake I see is guys thinking building a 383 magically makes more power, well it will only make more power if you feed it more air. 100% of the incoming and outgoing air moves through the heads. Meaning heads are more critical to power output than the addition of 33ci of displacement.
Depending on the casting number those aluminum heads are they might be a GREAT starting point for a skilled porter.
www.advancedinduction.com is who I had port my heads and spec the cam. Worked out well enough that it is the guys with strokers left making excuses about ET not me.

Don't get me wrong, I would love a stroker but I wont make the all too common mistake of spending money on a longer stroke crank and keeping poor performing heads. Spending money on heads first works out a whole lot better. Even my biggest critics will admit that my little stock shortblock 350 is making at least 460hp at the crankshaft, all in the proper heads and cam.
 

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Discussion Starter #5
So Mr Dwayne J, did you happen to snap a few pictures of
the ports before you put the heads on?

If you don't mind my asking, what did the cam spec out at
that you used?

As for the rear I already got a 3.08 posi / 8.5", rear disk from a
Impalla.

Thanks.....
 

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No pics of the ports.
Cam is 226/234 .565/.565 with 1.6 rockers on a 110 LSA. Probably wouldn't pass a sniffer test but runs and drives wonderfully.

Consider some 3.42-4.10 gears and a fresh posi in that axle. For a car that sees lots of highway time I really liked the 3.42s, but 3.73s are fine and the most popular, lots of guys are happy with 4.10s the OD and TC lockup keep rpms in check fairly well despite the gears.

My setup is actually a little outdated, these days they run a better spring, lighter valves and I think that has allowed them to change the cam specs some.
 

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Discussion Starter #7
I have 3.42's in the 92 and 93 I was looking more towards
a 3.73. The 2.93 that's in it gets 16 mpg local. ( I live in a
valley and I have a 250-300' hill I have to go over every time
I drive). The 3.42 gave me 18-20 (stock) local but it still
kinda lugs up THE hill.

I bought the 3.08 set for the disk brake setup, posi and
the sway-bar.

I was checking out Advanced Induction's sight.
It is really easy to turn one of these cars in to a money
pit. Heads, springs, cam, headers, cat back exaust, the list
goes on and on. Then you have to tune it.

On that note whose program will tune the 96 LT1 OBD2.
Spinning off of that...does the Camaro use the same computer,
part number? And or can a newer Camaro computer be put in
a Caprice ie re-pin and work?

Books just some how start them selves.......
 

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There is programming software for the LT1s, the 94-5 pcm is what I use as it is MUCH cheaper software. Computer plugs right in.

The same year Camaro does use the same pcm just different software in it.

I use Tunercat and Datamaster for tuning and datalogging , Under $250 total for all software and the cable to connect to the car.

They have figured out how to use a LS1 pcm on the LT1s, price is still high though.

You are right, the cost to modify a car is a high one, BUT smacking down a sprayed LS1 Camaro on the dragstrip with a big ugly "taxi" is priceless.
Here is one of the best race videos of my car.
Mustang versus Caprice video by 95SStorm - Photobucket

It's ugly because I drive it, and have unfortunately made a habit of hitting deer.:redface:
 

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Discussion Starter #9
13 @ buck4 haint too shabby.

Do you have to change anything to use the 94-5 computer?
 

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I soldered a resistor inside the pcm so I could keep the 96 knock sensor with the 94-5pcm, you could swap the knock sensor or I am told that you can actually just shut off the CEL code for the knock sensor and it will still function. The code get triggered when used with the wrong sensor because the pcm expects a certain ohms reading and it is a little different between the years.

The resistors are under $1 at Radio Shack.

In the video the Mustain ran 13s I ran 12.3 at 108.
The staging lane guy was more than happy to line us up when I asked.
Those Mustangs are shockingly light, from others I have seen weighed I had 900-1000lbs on that car.
 

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Discussion Starter #11
Do you have a link or pictures of the resistor mod?

Is that with stock exaust?

I feel your pain with the DEER thing, been there done
that. For some reason I always crush the pass side
headlight when I hit one.
 
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