Installation of the 4.9 engine

In late 2003 I decided to put a little more snap in the 85 SE. I thought about a 3800SC engine or a 350 SBC, but at the end of the decision making process I decided to go with the 4.9 Caddy. I contacted Ed Parks at the Fiero Factory to try and locate a low mileage engine. He had a remanufactured engine with less than 10K miles on it and that is all it took to get me hooked on this swap. In January of 2004 I decided to dive down to Ed's shop and look at the engine. I wanted to pick up the exhaust manifolds so I could get them ceramic coated before the engine swap. The swap was not going to be done until May of 2004. Ed said he could ship them to me, but I wanted to see his shop and see if I could drive one of his 4.9s. It took about 10 hour to drive down, 2 hours to look at the engine and tell him how I wonted the configuration, a half hour drive in his car (what a ride) and them I headed back home, all in an less than 24 hours.

Stock engine
We will start with a shot of the engine bay as the car entered Ed's shop. The swap started on a Monday morning about 7 AM, I was kind of sorry to see the 2.8 go, it never let me down or left me stranded. The engine was down and out within 3 hours. The V6 and trans axle was removed from the cradle and this gave me a chance to clean and power wash the cradle before the 4.9 was to be mounted to it.

After the engine cradle was cleaned up, I started working on the engine bay. I removed all of the insulation from the front and sidewalls. I found a couple of spots of rust and they got the wire brush and POR-15 treatment. I did make a new insulation blanket using a templet from Fireo Sails and got that installed before the cradle went back in. By Wednesday afternoon the Fiero Factory had the engine and transaxle on the cradle waiting for the welder to stop by and attach the front and rear engine mounts.

By Thursday late afternoon the new engine was back in with every thing reconnected. We would wait until the next morning to give it one last check and then go for a start. Friday morning every thing was checked once again and then the big moment arrived. It took a few tries, at first we thought the Passkey may be wrong, but on about the forth try it fired up. We think the problem was it took a few times of turning the key off and on to get all the air purged out of the fuel line. Now to check things out, all looked good but wait, the alternator was not charging. We put a brand new one on. The Caddy alternator is fairly large and in some installations the alternator hits the hood hinge. We installed a 93 Pontiac Bonneville 3800 alternator, as they are a little smaller. The problem was the charge lamp in the instrument panel, you must have one in the socket and it must be a good bulb. It was then off to the muffler shop. In the next picture you can see the tight clearance to get the exhaust system down and out the back. The next picture shows how we did it, a catalytic converter (yes, I like clean air) to a turbo tube and from there out the back. This really has a good sound, but then I have not heard a bad sounding 4.9. The intake system was put together with the stock air filter housing (with K&N filter) and the first couple of inches of the original Fiero air duct (Item A). The flex hose (Item B) is from a mid 80s Firebird (Part number 14056938) and they are still available from the dealer. I drove the car around that afternoon with no problems. Saturday morning I was up and headed for the dyno shop in Huntsville, AL. I am not going to tell you the results, as there were two things missing; Rockcrawl's chip and the VSS signal going to the ECM. From the dyno shop it was head north to Michigan, 630 miles and the engine did not miss a beat.

It is a year later and once again a group of Fiero nuts headed down to the dyno shop after Ed Park's swapmeet. This time the car preformed much better. The VSS was being sent to the computer and Rockcrawl's chip was installed. The dyno sheet show the difference with and with out the VSS to the computer. The blue lines are from the original run in 2004, and the red and green lines are the run in 2005. Want to hear what a 4.9 sounds like, The sound of a V8. Dial-up connections beware, it is a 3 meg file.

My last few words of wisdom are as follows:
1. If you are using a manual transmission you must supply the VSS signal to the ECM.
2. When recalibrating the tach to 8 cylinders, do not change the capacitor, change the resistor (or send it to me).
3. You need to contact Rockcrawl and get your chip reprogrammed.
Have fun and I hope to see you at the next Fiero show.