3400 DOHC Swap project

hastily produced to get things started. Pix are not the greatest but at least they are JPEGS and small in bytes.

The original 3.4L "TDC" as it was called (SAE Paper) Now called the DOHC

The original TDC plenum design

intake plenum is like a snail under the runners

the difference between throttle bodies on a Fiero and a 96 3.4L DOHC

after removing the throttle body runner, you can fist the airbox all the way to the back wall.... pre-96 3.4L DOHC owners will have no idea what this is like.

Yes, the two motors are the same width, it's just that the DOHC is wide all the way to the top

The DOCH DOES fit on an 88 cradle with NO mods (I like that)

Here's the standard 88 mount being used on the DOHC block. Only one bolt on the firewall side does not line up. I am not worried about it

The DOHC, in case you missed it, from it's BEST angle ALL heads. (notice the modified V-6 Fiero Thermostat housing)

The Difference between a 96 intake gasket and a 95 intake plenum notice that on the ports that line up, the 96 gasket is bigger.

I have no reference to the pre-96 exhaust, but LOOK at this gasket in reference to my hand.

Exhaust ports for days. Say "hi" to the dual exhaust valves.

A view with it sitting in the bay

Likewise, from the trunk point of view. One thing you cannot appreciate in this picture is that the accessory belt can be replaced entirely from above and while the motor is in the car, in seconds!!! Most all the crowded Fiero V-6 nastiness is releived, but still, some of that work must be done from underneath.

The stock exhaust asserting it's difference to the stock Fiero exhaust. If one used the DOHC manifolds, they'd have a LOUD and short system.

One nasty thing... The newer plenum makes a 96 swap a bit more crowded with a Getrag: two heater lines want to come RIGHT by the shift cable hook up. fuel lines want to be nearby, too. The Bleeder-valve radiator outlet gets replaced by pre-96 DOHC owners with a Coupe Thermostat housing, but the 96 has a different manifold and requires some fabbing, and cutting of the engine hoist ring

The beginning of my mock-up for fuel line routing to the battery side, so I can use the Fiero lines, and clean up the traffic jam that gets worse when you rote heater hoses, shift cables, radiator hose, accel cable, etc, all next to the air filter box. Too crowded, so I opted to re-route fuel, and probably, power brakes.

a few important mods, Fuel lines, no power steering (idler pulley), a Fiero dipstick, being used--and bent into place, for ease of use in a crowded bay, and a manufactured radiator hose from another car --being used.

The accel cable from a 87-88 coupe presumably works as is for pre96 DOHC throttle bodies. well, here it's different too. The end next to the pedal needs to have about 1/2" cut off from the inner black sleeve to let more cable come out to the throttle body. Also, the accel pedal-to-cable side must now be bent to compensate

(the pisser) Sooooo, you were admiring my ability to change plugs more easily than a Fiero V-6? So was I until I figured out then when the engine is placed correctly, the 2-4-6 bank wires cannot be removed unless you DROP the cradle. Yes folks. The other pictures do not show the proper perspective. I guess it couldn't ALL be fun and games.

Just in case you're wondering how I lift my Fiero at home. (front wheel chocks not shown)