I want to see the many different swaps and modifications done to both these engines. The reason being is I am trying to decide if I want to heavily modify the 2.8 that is already in my car or if I want to take a series III 3800 and put that it in instead. The thing being is I am trying to go for value wise. Which would be better. I would like to see modifications of any kind done to anyone that has a 2.8 in there GT. I am thinking it would probably be eaiser to get parts for a 3800 then a 2.8 fiero. I would have the 3800 put in by west coast fieros if I went that way. It would also be a crate motor from <a href=http://www.crateenginedepot.com/store/38-3800-Series-III-Supercharged-V-6-Engine-12499470-P829C0.aspx>here</a> and then I would have west coast put it in. If I was going with the 2.8 I would drop it and do it myself. There is something about the 2.8 I like but I just want more power out of it. Also what does anyone think of boring out the cylinder walls int he 2.8 and adding some darton sleeves to them?

Series III 3.8 Supercharged v6 starts at almost twice the power of the 2.8 v6 (260 vs. 130-140) so it is a much better starting point.

It doesn't take much at all to make 300+ with the 3.8, and you'd have to really, really work at it with the 2.8.

For 3550 (+ whatever shipping is) you're at a much better starting point. You'd spend that much making the 2.8 perform at the same level (to maybe slightly above) as the 3800, and you'd probably be approaching the ceiling on the 2.8's capabilities.

The 3800 does have some additional costs to it besides just the engine, which may move you back towards the 2.8 some, but if you can afford it (and the install) the 3800 is a much beefier engine with more aftermarket support.

If you started with a 3.4 block, you could do a bit better and stay with a 60degree v6, but even then you're at a much higher starting power point with the 3800.

This question can be considered a hot topic,not a flame on you 2.8 lovers.You can onley bore out the 2.8 so much befor the walls start becomeing too thin.The stock 2.8 engine was rated at about 130-140 hp but due to the exhaust manifold restrictions (they can be bored out)The actual horse power was about 120 or so hp.Cost wise,I would go for the 3800 (you can get a decent engine for $350).You can easiley put a smaller idler pulley on the 3800 SC and bring the hp up to 300.

A Basic Guide for stock Fiero hp gains.
A number of readers of this list have ask various questions about what they
can do to improve the performance of their V6 powered Fiero's. The following
was excerpted from "FIERO KITS-ALL FIRED UP!" by Herb Adams. Herb Adams has
raced a variety of Fieros over the years, and currently sells some of the
best suspension upgrade/racing parts for Fieros (see Peter's Fiero WEB page
for address and phone number). The article was published in the September
1991 issue of Kit Car. If you would like (and I find the time) I'll enter
the remainder of the article that covers tires, suspension and handling. (A
quick tease, Herb Adams on Fiero tires: The stock rear fenders have room for
Goodyear ZRS 255/50x16 tires on 16x9 wheels, although 255/50x16 on 16x8
wheels will also provide improvement.)

===============================================================

ENGINE ENERGIZERS

Even the fuel-injected V6 Fiero provides only average acceleration and top
speed, so many Fiero owners want to know what they can do to increase their
engine's power level, As part of the racing program, I conducted a series of
power development tests to determine ways to improve the output of a Fiero
V6 engine. Racing applications were at the IMSA Firestone Firehawk Events,
which allow open exhausts, so most of the testing was done in this manner.
The performance improvements, then, should be proportional of those found on
a car with a street-legal exhaust.

Before I made any changes, the stock V6 engine was dyno-tested "as
installed" with the factory's exhaust, air inlet, and electronics management
systems. As indicated by the power curves and the dyno data sheet, the Fiero
V6 engine produced a peak corrected horsepower of 110 at 4500 rpm,
significantly lower than the advertised 125hp. The difference might be
accounted for by differences in dynos, but the important thing for the
evaluation was to establish a good baseline.

Blueprinting an engine refers to the practice of bringing all the internal
specs and tolerances up to those published in the MVMA book. The process is
simple, but time-consuming because the engine must be removed from the car
and completely disassembled, My race team machined the block to provide
.005-inches of piston fit and to produce the minimum deck height allowed. We
also decked the heads to provide minimum chamber size. The bearings were fit
to .0020 / .0025-inch, and all the rotating parts were precision balanced.
Head porting is not allowed, but a precision valve job was done to ensure
the best possible air flow through the heads. Out dyno testing showed that
the blueprinting work increased peak output 3 horsepower at 4500 rpm and 17
horsepower at 5500 rpm. Less friction and better breathing help at higher
engine speeds, so if you're interested in using more rpm, it would be worth
the effort. Note that the test on the blueprinted engine was done with the
stock intake and exhaust systems.

Open exhaust tests showed a six horsepower gain from 4500-5500 rpm. This
system replaced the stock muffler and converter with a six-foot long,
two-inch diameter straight pipe. Such a system is to noisy for the street,
but it does show potential with an improved street-legal system. The open
exhaust test was run with the stock exhaust manifolds and with the stock air
inlet system.

The next stage of engine development involved a high-lift camshaft. Most
stock engines will see a power increase with more valve lift. We needed to
keep the idle equally smooth and the emission levels the same as the stock
engine, so we didn't increase valve timing. With a higher lift cam, the
valves are opened faster as well as farther, but the opening and closing
point are the same as stock. A high-lift cam increased the power level by 15
horsepower at 5000 rpm and 14 horsepower at 5500 rpm.

The level of increase might be less on a car with a street legal exhaust,
but the effects should still be rewarding. Installing a new camshaft in a
Fiero with the V6 engine requires removing the engine, so some owners might
want to switch to 1.60 rocker arms instead. The performance improvement will
be slightly less, but the installation is easier.

Inspection of the Fiero exhaust manifolds showed some manufacturing related
problems that severely restricted flow of exhaust gases. The attached sketch
shows where the manufacturer left excess metal inside the manifolds. After
these edges were ground away, power increased eight horsepower at 5000 and
5500 rpm. You can eliminate these edges on your Fiero exhaust manifold with
a small die grinder.

FLANGE __x_________x__ Grinding off excess metal
|_______________| in the exhaust manifold
| | can result in a significant
| | power gain. (Problem is at
| \ points marked with x's)
\ \
__________________\xx xx\_______________________

-------------------------> Flow of exhaust Gases
______________________________________________________
COLLECTOR

FIERO V6 DYNO DATA CORRECTED HORSEPOWER

(Approximated from chart) 3500 4000 4500 5000 5500 RPM's

Ported Exhaust manifolds 109 124 135 143 139 HP

Installed High-lift cam 103 117 126 135 132 HP

Blueprinted Engine w/Open Exhaust 99 112 120 119 118 HP

Blueprinted Engine w/Stock Exhaust 96 108 113 113 111 HP

Pure Stock Engine w/Stock Exhaust 94 107 110 107 94 HP
WHAT YOU SHOULD LEAVE ALONE

In searching for more power, my race crew tested the Fiero V6 engine on the
dyno without the stock air cleaner and inlet system, and we were surprised
to find that this produced no change in power. Apparently, the Pontiac
engineers did a good job on these parts because they work well, even though
they look restrictive.

Another alteration that made little or no difference was cam timing.
Advancing or retarding both the stock and high-lift cam resulted in power
level changes of only one horsepower, more at some rpms and less at others.
This shows that both cams are optimized at their normal position

Testing various PROM (Programmable Read-Only Memory) computer chips in the
electronic engine management system also showed that the Pontiac engineers
did their job well. Different PROMS with various fuel/air ratios and timing
curves showed no power improvement. We did choose a PROM with less full
throttle enrichment at high rpm to help our fuel economy during the
endurance races. This change gave us about five minutes more racing on a
tank of fuel, so we used it for many events. The last race was run at night.
The weather was cool so the air was dense. After about an hour of racing, we
burned a piston from being too
lean. We weren't too happy, but it showed again that the factory electronic
engineers usually know what's best for the average customer.

Owners of Fiero-based kit cars can make a number of performance improvements
with a relatively small investment of time and money. Using any of all the
above modifications will substantially improve speed and handling. Like most
things, though, the results will be proportional to how much effort and
money you choose to invest.

========================================================================

You could start with a K&N filter. They are supposed to flow more air and have a lifetime warranty of 1 million miles. Next you can get a bored out throttle body for the same reason. From there you can have the plenum extrude honed and gasket matched to the heads. The heads can have a performance rebuild consisting of new SI stainless valves, higher rate valve springs, hardened keepers and retainers, full roller rockers, and a pocket port. You also can get a CompuCam 2030 from Crane cams. This is the largest cam that can be used that the stock computer will still control. Have your fuel injectors cleaned and balanced for optimum performance. Get headers or have you stock exhaust manifolds ported so they will flow better. You also can get a new high flow catalytic converter and a performance muffler like the one Borla makes. For the auto tranny you can get a shift kit that modifies the shift points. The replacement chips are only good for full throttle and only give about 5 HP gain, they also make the motor run very rich, so they aren't worth it. You also can get an underdrive pulley, but some people complain about their charging systems when they did this. I had no problems with mine.

quote Originally posted by Nate16: If I was going with the 2.8 I would drop it and do it myself. There is something about the 2.8 I like but I just want more power out of it.

These two options are both viable, but they are not even in the same ballpark.

If you like the stock looking motor, or just want a little bit more hp or you like to mess around with motors yourself, then the modded 2.8 might be enough.

If you want a more modern engine, with lots of aftermarket the 3800 is obviously better.

The 2.8 is going to run out of potential long before it gets to the base horsepower of the 3800 so bang for the buck it's not the best way to go...

I have priced all the parts that I need for my 2.8 from various websites and also the labor and were talking pretty much as much as the 3800. I understand the 3800 has a lot more base horsepower. Witht the 3.8 I would also need the wiring harness and computer for it to that is also like an extra $700 there. Now I dont make that much money but believe me the 3800 has more appeal to me. It would take me half a year to save up for the 3.8 considering I still have to maintain the 2.8 in my GT until the time comes for the swap then I would have to drive the beat up protege at my house. I guess when it comes down to it Ill see how much money I will have by then. I still be looking for more input.

quote Originally posted by Nate16: I have priced all the parts that I need for my 2.8 from various websites and also the labor and were talking pretty much as much as the 3800. I understand the 3800 has a lot more base horsepower. Witht the 3.8 I would also need the wiring harness and computer for it to that is also like an extra $700 there. Now I dont make that much money but believe me the 3800 has more appeal to me. It would take me half a year to save up for the 3.8 considering I still have to maintain the 2.8 in my GT until the time comes for the swap then I would have to drive the beat up protege at my house. I guess when it comes down to it Ill see how much money I will have by then. I still be looking for more input.

I think there is a forum member that does wireing harnesses for about $400, then theres PJB (Canada) he allso does wireing harnesses.Loyde of Fast Fieros allso does harnesses (cost more money,but he's reputable and been doing engine swaps for years).You will also need the 3800 computer softwear edited.

do the 3800. wait a year. save the money. get the 4t6x eHD auto tranny while you;re at it. will save you the cost of the blown up getrag.
I put over 3000$ in parts and machining into my 2.8, and a stock 3800 would walk it without breaking a sweat.
it's bored, high comp pistons, cam, valves, headers, ported and balanced. sure it sounds nice revved to 6k. yes it is faster than stock, but for all that money, it did not put the power out I expected. and those costs are not for an assembled motor, I did that myself, along with all the detailing of the motor.
were I to go back and do it again, had I found this forum first, I would most definately done the 3800sc swap over the 2.8 rebuild.
it's a no lose thing. you get almost 2x the hp (over a stock 2.8), and almost 2x the gas milage (2.8's are not known for mpg), have a newer platform motor, and have alot more room for expansion in the power end.

I just sold a 2.8 Formula 5 spd. and still have my 3.8 SC II/ 4 spd auto Finale. It used to be fun to drive both on the same day. Night and day difference. As has been said here before you'd have to hot rod the crap out of a 2.8 and you would never achieve what a 3.8 can do on demand at anytime. Driving my 3.8 is relaxing with liquid power when you need it. Gas mieage? My Formula, on its' best fill-up pulled 28 m.p.g. My last fill up in my 3.8 was 27 m.p.g. with me getting on the gas off and on and even some mild street racing. I've had fill-ups that have seen 34 m.p.g. with mostly highway driving. In fact I liked the supercharged 3.8 so much I picked up an 07 Grand Prix GT for my daily driver. The supercharged and turbocharged power is very addictive on larger displacement 6 cylinder motors.

If you decide to swap, you should come check out my swaps and shop. I can do whole 3800 swaps for $4000 parts/labor turnkey, using auto or manual, and motors are under 65k.

I'm slowly starting to like the 3800 myself. If it just were legal in Cali. (some are I believe, but I haven't researched it)

Although it would be nice to use the Ecotec from the upcoming Chevy SSr. Direct injected and fwd. so it might be a nice swap.

Either way, i don't think the 2.8 makes any sense anymore. For looks and simplicity a 3.4 pushrod would probably do the trick. I might just have to do that one if my 2.8 dies (I hope it doesn't anytime soon)

-M

Hey, Austrian Import, my 3800 SC II came from Salinas, California and was indeed smog certified and passed. It has the complete OBD II system in it. I kept the certification sticker in the door. We don't even have smog check here but I thought I might need it in the future if I sold the car.

[This message has been edited by Darrelk (edited 09-17-2007).]

RideZiLightning,

You shsould give me the address to your shop I would like to come and check out your 3800 swaps. Your prices on the swaps with a turnkey sound great.

I have the 2.8 stock with turbo, a Nissan ZX 300 T/3. It's fun but if I had to do it again I would go the 3800 SC series route.

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