1999 Firebird with M90 conversion

[Mighty Thor]

Re: 1999 Firebird with M90 conversion

How did you extend those sensor wires?

[Docta]

Re: 1999 Firebird with M90 conversion

Since I'm an idiot, what're the three prongs on the edge of the intake? And is that a stock TB?

[Bird_Of_Prey]

Re: 1999 Firebird with M90 conversion

The ignition module bracket is a fwd one from a Bonneville. This is identical to what is used on the Holden cars and works well for the rwd applications. I had to custom make a lower idler pulley bracket due to the power steering pump mounting where the fwd bracket goes, and on an F-body the steering rack is in the way to move the pump out of the way.

The trans is a 4L60E with a few upgrades

Interesting. So you're using the stock L36 PCM?

[Oldsaddict]

Re: 1999 Firebird with M90 conversion

It is the stock pcm but reprogrammed. This is the 4th rwd boosted setup I have done with a F-body pcm and they work fine just take a bit of time to tune and I have a baseline to start with since I have done similar before. Idealy it would be nice to use a fwd pcm from an L67 car but several problems arise, at least with an auto trans. The 99+ cars make it worse since they are drive by wire.

[Bird_Of_Prey]

Re: 1999 Firebird with M90 conversion

It is the stock pcm but reprogrammed. This is the 4th rwd boosted setup I have done with a F-body pcm and they work fine just take a bit of time to tune and I have a baseline to start with since I have done similar before. Idealy it would be nice to use a fwd pcm from an L67 car but several problems arise, at least with an auto trans. The 99+ cars make it worse since they are drive by wire.

That's exactly what I was thinking. Would you be willing to make these as kits?

[Pewter02Camaro]

Re: 1999 Firebird with M90 conversion

That is some beutiful fabrication work right there!

[Oldsaddict]

Re: 1999 Firebird with M90 conversion

Thanks again guys!

Before I started the project I had wanted to do this for the past few years to be able to offer a kit, but after doing this there is just soo much more to it than a few parts. The blower housing and inlet tube are no problem to make more of nor is the thermostat housing. I also made a custom idler pulley bracket which took a bit of time to get proper fitment but works well. The time and conflict is all in the swap itself due to wiring and relocating a number of parts. The upper radiator hose is something that will have to be custom made. Different years have different pcms and underhood wiring and a custom tune is a must. I am seriously thinking about making a handful of blowers like this and thermostat housings to offer as a universal rwd set. These could be bolted to any 3800 S2 or S3 engine with supercharged/L67/L32 heads and L67 lower intake and the rest is up to the installers imagination. There is an aweful lot of time and frustration that this swap is going to bring anyone and I dont think I can willingly sell the parts as a "kit" as I dont want anyone to think this is a weekend project. I spent a lot of extra time on this particular car due to dropping the entire engine and trans out the bottom and made custom supports to do so. Not many people are going to go that route and this could definately be installed as part of a top swap. If I had the engine harness it would be no problem to modify it to work with this setup if all of the parts were arranged the same. I am not a vendor on this forum and dont want to advertise anything but if there was enough interest I would seriously look into it more. I just know what I went through to get this finally finished and what the few other guys went through. If you want something different this is definately an attention grabber. Below is a short list of things needed to do this

-L67 or L32 heads
-L67 lower intake manifold
-L67/L32 valve covers and matching gaskets
-L67/L32 style fuel rail
-Larger fuel injectors, L67 work fine unless you are planning a higher HP buildup
-L67/L32 dual belt balancer and bolt
-M90 supercharger and inlet tube custom made to fit
-Custom thermostat housing
-Wire harness modifications
-Custom upper radiator hose
-Move/relocate power steering fluid res, AC lines, Brake lines at ABS module
-Evap solenoid with custom mounting bracket and tubing
-Modify transmisison fill tube
-Custom vacuum lines
-Throttle body of choice, year dependant as 99+ is dbw. LS1 tb works well for pre 99
-External maf sensor if using a throttle body that does not have one integral
-Bonneville style ignition module bracket and SC idler pulley bracket with tensioner
-Custom intake pipe/tubing
-Custom pcm tuning
-Modify fuel lines depending on what fuel rail you use
-Upgraded fuel pump that will support higher fuel pressure for boosted application

An alternative to running the dual belt setup would be to use the ZZP SS M90 style offset supercharger pulley and run a single belt. You dont get near as much belt wrap with this setup but it is an option and saves a bit of work and parts. That is what I can think of off the top of my head but Im sure there are things I left out.

Here are additional things done to this particular build-

-Racetronix W-body fuel pump kit (suggested for this vehicle from Racetronix)
-Racetronix LS1 Fbody fuel pump hotwire kit
-Automatic transmission upgrades to handle higher power, looser torque converter
-Engine taken apart to reseal
-Intense Racing S1X Blower cam
-105lb springs and modified retainers
-Rebuilt L67 cylinder heads
-180 deg T-stat
-New water pump
-New timing chain and dampener
-New LS2 lifters
-04+ style oil pump spring
-Pacesetter headers

[Bird_Of_Prey]

Re: 1999 Firebird with M90 conversion

I would just need the modified parts. I can take care of the install, wiring, and locating the necessary stock parts. PM me a round $#.

[96blackmaro]

Re: 1999 Firebird with M90 conversion

Yea, if you made the the just the m90s and maybe the thermostat housing I believe the rest isnt all that bad.

[Oldsaddict]

Re: 1999 Firebird with M90 conversion

Here is a finished pic with the intake tubing that I used. I had a few odds and ends left to finish up like the evap solenoid and line, pcv hose, and extending the iat wires and it is all complete now. I had a chance to drive the car around a little bit a few days ago and its feels pretty strong. It had old gas in the tank and I didnt have my wideband in so I didnt make any heavy throttle runs but did get about 60% in it a few times and was worth a smile or two so definately will be nice to get it back on the road once the weather allows and get the tune dialed in. I would like to try and take the car and dyno it or at least hit the track once it opens in April and I will report back with how it does.

[whitdog54]

Re: 1999 Firebird with M90 conversion

came out really good. great work.

Stock lid...is it atleast shaved?

[ssms5411]

Re: 1999 Firebird with M90 conversion

Thats a outstanding job, looks like it came that way. Great job.

[Bird_Of_Prey]

Re: 1999 Firebird with M90 conversion

Let me know when you're taking it to the track. I'd really like to see this in person.

[Oldsaddict]

Re: 1999 Firebird with M90 conversion

We will likely go to Muncie Dragway with it since it is only about an hour from here, well almost 2 for the owner lol but that is typically where we go unless there is an event or group going somewhere else. US41/Moroco is a nice track with good traction but is a bit of a drive for us so we dont head out west often.

[Bird_Of_Prey]

Re: 1999 Firebird with M90 conversion

Doesn't matter where to me! I'll trailer my Camaro anywhere.