1988 Fiero with 4.9 Cadillac V8 conversion.... going supercharged...
some quick history....
Its an 88 base model fiero.... used to be a 4 cylinder automatic
.... a few years ago I swapped in the Cadillac 4.9 V8... and also swapped over to a 5 speed Isuzu manual transmission.
I used an ECM and wiring harness from a 1991 Camaro Z28 305 Tuned port injection.... This worked quite well despite that some said it wouldn't work on the 4.9
A few months later I found a Cadillac Allante in a junkyard.... and I quickly bought the intake and swapped on my 4.9 and noticed the a pretty good gain in acceleration.
About a year later... I broke the isusu transmission and I replaced it with another newer isuzu from a 1999 cavalier.... This isusu lasted about two years and then it also cracked ....
And so I found a Getrag 282 from a 1993 Beretta 3.1 ..... Got some shift linkage adapters from Rodney Dickman.... and this transmission has lasted up to the present day
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and grinded a notch it the deck lid to clear the supercharger snout
... and grinded on the alternator mount so that the alternator would sit as low as possible...... so that in turn the supercharger would sit as low as possible to clear the hood
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Test fitting the plenum base plate..... Where ever there was a threaded hole in the allante intake, I drilled a corresponding hole in the metal base plate.... This was done for strength, to hold the supercharger steady....as it takes force to drive a supercharger
[This message has been edited by MaxCubes (edited 03-11-2015).]
This drawing shows what holes I will use and not use....
The orange line indicates the plenum mounting surface
The black line circle indicates where the 4.9 distributor is
In the yellow circle area... I will seal off the bypass valve passage with a freeze plug. This has to be done because the 4.9 distributor is in this area.
The blue area is where I plan to grind a new hole into the bypass passage... so that the bypass valve will still be functional and allow air to flow from the plenum
The rib in the red circle will be grinded away to allow air to flow from the plenum to the bypass passage
The pink circle is where the pcv valve pulls crank case gas... I will plumb this to a valve cover on the 4.9
The purple circles are ports that will need to be plugged
The green circles will not be used and will be covered by the metal plate
[This message has been edited by MaxCubes (edited 03-11-2015).]
The GEN 5 supercharger has a larger outlet versus older generation superchargers....
This photos illustrates the difference....
This is a 3800sc II manifold with a series 3 intake gasket laid on top.... you can see the area that would need to be grinded away to use and GEN V supercharger
[This message has been edited by MaxCubes (edited 03-11-2015).]
I wish I had a fifth of you knowledge when it comes to engines. Awesome work!
Thanks for the kind words....
I am definately low buget and so I do all my own work. Most of my performance upgrades are parts from the junkyard. ....one can learn a great deal just browsing around the yard and doing research.
.... for example, before I bought the supercharger... I unbolted it from the grand prix and took it to a cadillac deville in the same junkyard ....set it on top of the 4.9 and did some of my research and development poor man style
And here is a shot of the 3 inch pulley I order from Pulley Boys...
The stock pulley is 3.8... so I am hoping the 3 inch pulley will get boost up to a decent level
you can easily see the difference in size...
This will also get the heat up to blow the engine up level. You WILL need a intercooler and supporting mods for a 3.0 pulley. 3800SC guys can't just pulley down without Cam or 1.9 Rockers, IC, headers, etc. Also, you may need bigger injectors as the M90 will flow enough air to max out 36# injectors on a V6. What size injectors do you have anyway?
.... To my surprize it started up... no problem.... no check engine light
Idles quite well... with bypass open...
.... Idles rough like if it has a lumpy cam when the bypass valve is closed... and makes that supercharger whine when reved with bypass valve closed.
No supercharger noise when bypass valve is open.
I haven't really driven it yet since I don't have the throttle cable connected to the throttle yet.
Even when I do connect the throttle .... I will keep the bypass valve open untll I can get the ignition timing and extra fuel needed first. .....I will try to post a short video on youtube with the engine running... maybe in a day or two
