3400 Engine

Home Supercharger

3.4L engine, headers & Borla exhaust

Engine Swap Details

This swap utilizes a '96 Pontiac Transport van
FWD 3400 engine short block with roller cam. 

(Now Super-Charged - click BUTTON above) 

To retain the Fiero intake and fuel system, Fiero heads are used in place of the aluminium heads a 3400 engine would come with.  Because of the larger combustion chambers in the Fiero's iron heads, you will have change to new pistons

The only roller cam available is the stock one, along with stock roller lifters and timing chain. No aftermarket is available for these items. GM didn't have an engine with the iron head/roller cam combination, so there are no proper length push rods - they are either too long or too short. Because of the taller height of the roller lifters, custom length push rods had to be ordered from Smith Brothers.

To gain better breathing, we went with Comp Cams 1.6 to 1 ratio roller-tip rockers to increase valve lift.  The throttle body was bored, and intake manifolds gasket matched and ported. The heads were ported with most of the work being done in the valve pockets and exhaust side.  Stainless steel valves were installed with SBC valve springs and retainers.  

Headers are used instead of the stock exhaust manifolds, with a free-flow catalytic convertor and BORLA cat-back exhaust system.  It sounds great and lets the engine breathe well.

Because this is a FWD block, the starter bolt holes are on the correct side. Just bolt on a stock Fiero starter and you're set.  You will need a "zero balanced" flywheel, either a new one, or get your pre-88 flywheel rebalanced.  The machine shop just machines off the weight to balance it out.  There may be some sensor holes not required for the Fiero installation.  These can be blocked off with appropriate plugs.

NOTE - there is a pressure bypass hole behind the water pump in the timing cover that has no corresponding hole in the 3400 block. This needs to be plugged, otherwise coolant will spill onto the ground when you fill engine. I drill a 1/8" hole in the edge of thermostat to perform this same function.

Most everything else is a normal rebuild procedure, with a careful selection of parts to upgrade all engine support systems.  There's no point building a performance engine with an inadequate fuel system, poor ignition or plugged up exhaust system. 

(Click thumbnails for larger image)
upperend.jpg (18662 bytes) Engine's upperend components.  Plenum and Valve Covers have been stripped and repainted.  Bright red Taylor plug wires are a good replacement for the original red GM wires (no longer available).  Bright red Holley coil and red distributor cap complement the engine parts. K&N filter and new starter await installation. 
View websites for Holley coil, K&N Filters and Taylor Wires.
headers.jpg (18961 bytes) FOCOA headers and Y-pipe are ceramic coated.  This has two purposes-
- it keeps the engine bay cooler as engine heat transfer is minimized.
-the coating has excellent corrosion resistance, so they'll last almost forever. 
These are available from various sources.  Race-Tech in Canada has 'em.
clutch.jpg (21703 bytes) A Centerforce Dual Friction clutch/pressure plate kit will be installed.  These have been reported to work very well in the Fiero powertrain.  Although not shown, I'm also installing an aluminium flywheel. These are a perfect match, and should help "get the power to the ground".  Centerforce website
fuelrail.jpg (9535 bytes) The stock fuel rail is shown with Holley Adjustable Fuel Pressure Regulator (AFPR) (located at the lower end in picture).  I chose a Holley unit, because it has a large knurled wheel on top to adjust fuel pressure settings.  Adjustment  is easy without need of a wrench, although long thin fingers do help ;-)  Holley AFPR
lifters.jpg (24548 bytes) Here's a closeup of the valley.  You can see the roller lifters in their bores. The lifter bores are round, as is the lifter, but the upper third of the lifter has been machined flat on two sides.  These are to prevent rotation of the lifter once the lifter anti-rotation retaining rails have been installed.  
rails.jpg (26087 bytes) Looking from the front of the block, you can see the plastic lifter anti-rotation rails installed. A raised edge needs to be ground off the inner side of the rails, as done on the left rail.  The regular rail is on the right for comparison.  This is required for clearance so that the Fiero lower intake manifold can be installed.
valley.jpg (30170 bytes) A large photo shows the valley with both modified rails installed.  The valley has more reinforcement webbing than 2.8 blocks as is readily apparent on closer inspection.
intake.jpg (13945 bytes) Another modification is required to in order for the stock Fiero lower intake to fit over the lifter anti-rotation rails.  The oil splash shield on the bottom of the intake must be either bent or removed.  I opted to bend them slightly, requiring several test fits to get it right.  With this spash shield in place, hot oil splashing on the bottom of the intake is reduced. 
rockers.jpg (14483 bytes) Because the stock cam is the only roller cam available for this engine, CompCams 1.6 to 1 ratio roller-tip rockers will be used to increase valve lift and improve breathing. The Comp Cams rockers will fit under the stock valve lifters without any problems. Custom 5.85" long pushrods (stock diameter) were ordered from Smith Brother Manufacturing (541) 388-8188.  Cost is under US$100.
oilpan.jpg (14777 bytes) The 3400 engine has a strong, ribbed cast aluminium oil pan.  No pan gasket is used, as RTV sealant is applied during installation to provide a leakproof seal.  In addition to bolts attaching it the block, six bolts go through the side of the oil pan into the main bearing caps. A stock Fiero or 3.4L Camaro pan will not fit!!  The stock 2.8L harmonic balancer is reused and new under-drive pulley and water pump is also installed.
header.jpg (29273 bytes) The engine is now installed on the cradle. More accessories had been installed, such as the oil filter, sensors, alternator and starter. The FOCOA headers are clearly visible. The BORLA cat-back exhaust system can also be seen here.
plenum.jpg (17527 bytes) Here, the plenum and valve covers are test fitted.  The heat shielding around the Y-pipe has been trimmed to fit the new one that came with the headers. The EGR valve and Holley coil are installed in their proper locations.  Also visible, are the Torque Master spark plugs, which look like any other at this end.
tmplugs.jpg (14922 bytes) Torque Master plugs have a radial ground/center electrode design.  These came highly recommended from another Fiero owner with a high performance 3.4L engine. The tip design exposes the spark more directly in the combustion chamber for more power.  Their alloy construction means they should last the life of the engine.
34engine.jpg (31229 bytes) Engine looks right at home in the Fiero's engine bay.  Fiero owners would spot the headers as being non-stock.  Everything else looks pretty much as it did from the showroom floor.  

Some people who've never seen a stock Fiero setup assume everything is "dress-up", while others believe everything is stock.  I kinda have both of them fooled.

egrcover.jpg (27852 bytes) Here's a cheap dress-up item I came across some time after I took these pictures of the new engine.  This is a GM EGR valve cover. It is now a discontinued item, but you'll find them in the wrecking yards on 80's Oldsmobile Ciera's with a fuel injected V6.  They just snap on/off.  They're very handy to cover up an old rusty EGR valve, or to keep a new EGR valve looking... well new!!!



Custom PROM chip for 3.4L 5-speed - Wester's Garage, Tilley AB, www.ecmprogrammer.com

'96 Pontiac Tranport van FWD 3400 V6 core - bored .020" over
3.4L DOHC pistons Federal Mogul H684CP (gives 9.7 CR) .020" oversize
- similar to Silvolite PN# 3409 www.kb-silvolite.com/slvpg79.htm
Stock rods - polished, resized & shot-peened,

Stock 3.4L DOHC crankshaft - polished and balanced
Stock cast iron heads - ported  w/new valves, valve guides & seals
Si SS valves - 1.72"/intake 1.42"/exhaust (Fiero Store) www.fierostore.com (US)

Stock GM 3400 roller cam no aftermarket available

Stock GM  roller lifters no aftermarket available

Stock GM timing chain and gear set (specific to roller cam) no aftermarket available
Comp Cams 1.6 ratio roller tip rockers PN# 1414-12 www.compcams.com

Custom length pushrods 5.85" long - Smith Brothers Manufacturing www.pushrods.net/

Engine assembly computer balanced
New under-drive pulley (Fiero Store) www.fierostore.com (US)
Fel-Pro 3.4L engine gasket kit
New EGR valve - GM PN# 17110831
180 thermostat - Motorad PN# 211-180
Engine "long block" painted (BLACK) - Mar-Hyde Universal Black 8560 www.marhyde.com
New water pump - TRW/Carter PN# FP1843 www.trwauto.com

Intake/Fuel System

K&N air filter - PN# E-0890 www.knfilters.com/airfiltr.htm
Bored throttle body (55mm) - RS Motorsports
webhome.idirect.com/~rsm1/main.htm (Canada)
Ported stock intake manifolds matched to bored throttle body and head gaskets
Fel-Pro Fiero intake gasket set PN# MS 93020
AC Delco V8 fuel pump - EP381 PN# 25163473  www.acdelco.com
AC Delco fuel pump strainer - TS-1 PN# 25055455

AC Delco 3.4L DOHC injectors - PN# 17090849 (20% more flow than standard 3.4L injectors)
Holley adjustable fuel pressure regulator - PN# 512-501 www.weiand.com


Stock distributor w/new pickup coil installed
New dist/coil harness (Fiero Store) www.fierostore.com (US)
Wells Professional cap & rotor (RED) PN# DR-2012G
Taylor Spiro-Pro spark plug wires (RED) PN# 74224 www.taylorvertex.com
Holley ignition coil (RED) PN# 820-214 www.weiand.com
Torque Master spark plugs www.

Engine Electrical

New starter - Canadian Tire (5 yr warranty)

New alternator (115amp) - Auto World, Calgary AB
Some sensors and connectors replaced - AC Delco parts
Engine harness cleaned up & re-loomed

Exhaust System

FOCOA headers
- Jet-Hot coated www.thefieroshop.com  (Canada)
Fel-Pro exhaust header gaskets - PN# 1449
Stainless Steel Super-Flow catalytic convertor - CarLine Muffler (Canada)
BORLA Stainless Steel exhaust system w/tips http://twinlakesfiero.tripod.com (US)

 Transmission - Stock Getrag 5-speed

New 1st/2nd and 3rd/4th synchros and diff. bearings - GM

Aluminium flywheel (zero balanced) www.thefieroshop.com  (Canada)

(NOTE: Stock 2.8L flywheel can be resurfaced and zero balanced)
New axle seal/bearings (Fiero Store) www.fierostore.com (US)
Center-Force Dual-Friction clutch w/pressure plate www.centerforce.com
New clutch release bearing - GM
Synchromesh Transmission Fluid w/Limited Slip additive
- GM



Engine cradle is cleaned and repainted (BLACK) - Mar-Hyde Universal Black 8560
Plenum and valve covers repainted (RED) - Dupli-Color Chrysler Industrial Red DE-1632
Intake manifolds and aluminium heat shields painted Rust-oleum V2116 High Temperature Aluminium http://www.rustoleum.com 
All engine brackets repainted (BLACK) - Mar-Hyde Universal Black 8560
New Prothane Poly cradle bushings PN# 7-502 www.prothanesuspension.com
All new Goodyear radiator and moulded heater hoses www.goodyearbeltsandhose.com



Sites where I found useful information on building up a 3.4L engine.

3.4L Fiero engine buildup (Freddy Clark) www.angelfire.com/on/freddysplace/
3.4L S-15 engine buildup www.s-series.org/htm/windstorm/project-windstorm.htm
What's involved using Camaro 3.4L www.angelfire.com/on/fierofactory/start.html#34
Intelligent mods - what to do, what to avoid www.sdsefi.com/techmods.htm
Rebuilding a 60 degree V6 - bores/displacements
GM Performance Parts on-line catalog www.spoperformanceparts.com
60 degree V6 performace parts listing
WhiteHorse perfomance engines www.kitcar.com/whitehorse/