V8 under the hood of a LeSabre???
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Hey guys, i'm still dreamin. But a man can dream, can't he??
Ok, heres the deal. I was watching a co-worker work on a 91 Cadillac Deville Sedan. It was FWD, and had a 4.9 liter V8. (nice car, by the way, real decent shape).
While the car was in the air, I could picture that engine cradle in my LeSabre, along with the caddy V8 and Transaxle. It looks like it would fit, and the Cadillac Deville, is basically a stretched H body, isn't it? Exact same stuff.
So, you have a lighter car, (my LeSabre) to stick that 300 CID V8 in, and yeah, you get the picture, a V8 Buick!!
Is it worth it? How much Torque and HP do these V8'* produce? Are they durable? Get good gas mileage??
If its a bad idea, let me know, I love to get opinions on things like this..
One thing'* for sure, a Caddy V8 would sound sweet in my old Buick!!
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Ok, heres the deal. I was watching a co-worker work on a 91 Cadillac Deville Sedan. It was FWD, and had a 4.9 liter V8. (nice car, by the way, real decent shape).
While the car was in the air, I could picture that engine cradle in my LeSabre, along with the caddy V8 and Transaxle. It looks like it would fit, and the Cadillac Deville, is basically a stretched H body, isn't it? Exact same stuff.
So, you have a lighter car, (my LeSabre) to stick that 300 CID V8 in, and yeah, you get the picture, a V8 Buick!!
Is it worth it? How much Torque and HP do these V8'* produce? Are they durable? Get good gas mileage??
If its a bad idea, let me know, I love to get opinions on things like this..
One thing'* for sure, a Caddy V8 would sound sweet in my old Buick!!
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This swap is very do-able...
When I still had my 84 Celebrity wagon I wanted to replace the weak 2.8 V6.
Somebody on the A Body Forum posted a pic of a Pontiac 6000 with a 350 Chevy.
This really got me interested... And I started to do some research.
I found out that it was done with a kit made by a guy named Archie...
He makes them for Fiero swaps... Well the kit alone is 950 bucks (OUCH)
So I started to lurk around on a few of the Fiero Forums and found out about the ability to use the Caddie 4.5 and 4.9 engines.
These engines use the same tranny bolt pattern that is used in all the front wheel drive GM'*, Fiero too even though it is a mid engine it uses a FWD type trans.
The 4.9 is aluminum and is almost the exact same weight as a 2.8 so you don't have to change the front springs due to a heavier V8.
You dont need to change the cradle or the trans... but you do need a donor car for all the computer stuff etc.
I was going to look for a rear ended 91 or newer DeVille.
Or you can do a "Dumb" car, using old school "coil and a carb" setup.
Some where I think I have some links to how to do the Dumb system using readilly available parts.
As to the sound... with Flow-Masters a Caddy 4.9 sounds just like a 'Vette.![Cool](https://www.gmforum.com/gm/images/smilies/icon_cool.gif)
CD
When I still had my 84 Celebrity wagon I wanted to replace the weak 2.8 V6.
Somebody on the A Body Forum posted a pic of a Pontiac 6000 with a 350 Chevy.
This really got me interested... And I started to do some research.
I found out that it was done with a kit made by a guy named Archie...
He makes them for Fiero swaps... Well the kit alone is 950 bucks (OUCH)
So I started to lurk around on a few of the Fiero Forums and found out about the ability to use the Caddie 4.5 and 4.9 engines.
These engines use the same tranny bolt pattern that is used in all the front wheel drive GM'*, Fiero too even though it is a mid engine it uses a FWD type trans.
The 4.9 is aluminum and is almost the exact same weight as a 2.8 so you don't have to change the front springs due to a heavier V8.
You dont need to change the cradle or the trans... but you do need a donor car for all the computer stuff etc.
I was going to look for a rear ended 91 or newer DeVille.
Or you can do a "Dumb" car, using old school "coil and a carb" setup.
Some where I think I have some links to how to do the Dumb system using readilly available parts.
As to the sound... with Flow-Masters a Caddy 4.9 sounds just like a 'Vette.
![Cool](https://www.gmforum.com/gm/images/smilies/icon_cool.gif)
CD
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L67 swap would probaly be cheaper...I venture to say you have the torque axis mount already as well so if you can only find a wrecked ssei to swap from.
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well i've done three of these v-8 swaps into fiero to date so i can help you out here...
the "dumb car" idea proposed here is simply put a dumb comment from someone who doesn't know any better. replacing the throttle body with a 500-600 cfm holley carb actually yeilds more power. and it'* easier. trust me i've done both.
the ignition is handled using parts from the original caddy distibuter and a B-O-P sb v-8 HEI distributer.
before installing the carb, air gap the manifold with a dremel. this is worth 5 horse... also seal off the EGR tubes, you don't want them. they're in the bottom of the manifold directly below the carb plate. block off the injector bungs with plugs, you'll want thos ports availible in case you ever decide to go nitrous. these motors will hold 125 shot stock, so no problems there.
if you choose not to go carb, a man by the mane of rockcrawl on pennocks.nl makes harnessess and burns chips for this motor. further research will yeild you an LT-1 throttle body adapter kit. another option is to use the 4.5 allante intake manifold. a far superior F.I. setup
i'd recommend getting a weilder or a friend who weilds before you start. fabbing up mounts is actually pretty simple. just use bar steel and weild it into an L, then use poly GM trans mounts. it holds just fine.
this motor is really choked up on the exhaust side, for the time being there isn't much you can do about that. by using two front manifolds off an eldorado you can avoid the crossover pipe and run true dual exhaust. make sure you use an H-pipe to equalize the banks though. this will really open up this motor. and it does sound bad assed. rumbles like a cammed small block.
there are cam regrinds and aftermarket rockers available.
basicly this is a motor. all the old hot rod tricks will work. you can easily get about 230 horse and close to 300+ torque.
now the 4.9 vs 3800 is a hotly contested issue on every fiero board. theyre at each others throats constantly. the bottom like is this. in identicly prepared cars (fieros in this case, fiero guys use S2 motors) a 3800SC car is faster than a 4.9 in the 1/4 mile. in the 1/8 mile the 4.9 will win every time. generally speaking the 4.9 is much cheaper than the 3.8.
they're both awesome motors, so the choice is really up to you. but i'd say go for it. you can PM anytime you'd like if you need any more information. good luck with whatever swap you decide to do.
the "dumb car" idea proposed here is simply put a dumb comment from someone who doesn't know any better. replacing the throttle body with a 500-600 cfm holley carb actually yeilds more power. and it'* easier. trust me i've done both.
the ignition is handled using parts from the original caddy distibuter and a B-O-P sb v-8 HEI distributer.
before installing the carb, air gap the manifold with a dremel. this is worth 5 horse... also seal off the EGR tubes, you don't want them. they're in the bottom of the manifold directly below the carb plate. block off the injector bungs with plugs, you'll want thos ports availible in case you ever decide to go nitrous. these motors will hold 125 shot stock, so no problems there.
if you choose not to go carb, a man by the mane of rockcrawl on pennocks.nl makes harnessess and burns chips for this motor. further research will yeild you an LT-1 throttle body adapter kit. another option is to use the 4.5 allante intake manifold. a far superior F.I. setup
i'd recommend getting a weilder or a friend who weilds before you start. fabbing up mounts is actually pretty simple. just use bar steel and weild it into an L, then use poly GM trans mounts. it holds just fine.
this motor is really choked up on the exhaust side, for the time being there isn't much you can do about that. by using two front manifolds off an eldorado you can avoid the crossover pipe and run true dual exhaust. make sure you use an H-pipe to equalize the banks though. this will really open up this motor. and it does sound bad assed. rumbles like a cammed small block.
there are cam regrinds and aftermarket rockers available.
basicly this is a motor. all the old hot rod tricks will work. you can easily get about 230 horse and close to 300+ torque.
now the 4.9 vs 3800 is a hotly contested issue on every fiero board. theyre at each others throats constantly. the bottom like is this. in identicly prepared cars (fieros in this case, fiero guys use S2 motors) a 3800SC car is faster than a 4.9 in the 1/4 mile. in the 1/8 mile the 4.9 will win every time. generally speaking the 4.9 is much cheaper than the 3.8.
they're both awesome motors, so the choice is really up to you. but i'd say go for it. you can PM anytime you'd like if you need any more information. good luck with whatever swap you decide to do.
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now the 4.9 vs 3800 is a hotly contested issue on every fiero board. theyre at each others throats constantly. the bottom like is this. in identicly prepared cars (fieros in this case, fiero guys use S2 motors) a 3800SC car is faster than a 4.9 in the 1/4 mile. in the 1/8 mile the 4.9 will win every time. generally speaking the 4.9 is much cheaper than the 3.8.
wouldnt that be the other way around? I would thing the 3800 would win in the 1/8th and the 4.9 would win in the 1/4 with its longer legs? whats the reasoning behind that?
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Originally Posted by LittleHoov
now the 4.9 vs 3800 is a hotly contested issue on every fiero board. theyre at each others throats constantly. the bottom like is this. in identicly prepared cars (fieros in this case, fiero guys use S2 motors) a 3800SC car is faster than a 4.9 in the 1/4 mile. in the 1/8 mile the 4.9 will win every time. generally speaking the 4.9 is much cheaper than the 3.8.
wouldnt that be the other way around? I would thing the 3800 would win in the 1/8th and the 4.9 would win in the 1/4 with its longer legs? whats the reasoning behind that?
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there'* not a whole lot of flow in those heads, so the 4.9 doesn't have those longer legs you speak of. the regrinds do a bunch to up the top end, but it'* still pretty low.
right now the limits of the 4.9 are being pushed. alot of guys are upping their compression and using northstar or quad four pistons, others are running low amounts of boost or nitrous.
heres a few of the boards and links for this engine:
http://groups.msn.com/FieroCaddySwapGroup/general.msnw
http://fp.enter.net/~rockcrawl/caddy49b.html
http://www.fieroaddiction.com/caddy49a.html
http://groups.msn.com/AkimotosV8FieroClub/shoebox.msnw
check out the 5.1 turbo/nitrous motor
right now the limits of the 4.9 are being pushed. alot of guys are upping their compression and using northstar or quad four pistons, others are running low amounts of boost or nitrous.
heres a few of the boards and links for this engine:
http://groups.msn.com/FieroCaddySwapGroup/general.msnw
http://fp.enter.net/~rockcrawl/caddy49b.html
http://www.fieroaddiction.com/caddy49a.html
http://groups.msn.com/AkimotosV8FieroClub/shoebox.msnw
check out the 5.1 turbo/nitrous motor