2.8L vs. 4.9L (Page 1/3)
zzzhuh NOV 04, 10:36 PM
It has been a long time since I've been on the forums, and I'm glad to be back. I hope everyone is out there staying safe during all of the madness that 2020 has caused.

My 2.8L Fiero hasn't ran in 3 years, due to moving as well as not having the time to replace the water pump. It currently does start and run, but I obviously don't run it for very long due to no coolant currently being in the car.

I am looking to replace the following things, which I currently have already purchased:
-Water Pump.
-Exhaust manifolds (I also want to port them and put new FelPro gaskets in)
-Rear Struts (I got KYB's)
-Slave Cylinder (Rodney Dickmans)
New coolant
New brake fluid and clutch fluid

With these things in mind, it seems that the best way forward is to remove the engine entirely, as I will be able to get to all of the bolts for the water pump, and I don't risk the same problem with those bolts that hold on the exhaust manifold. I figure that while the engine is out, I replace the valve cover gaskets, and it seems that there is black grim near the middle intake manifold under the red 'Fiero' Plenum, which means it could have been the valve cover, or worse.. The lower intake manifold gasket.

If I go this route, that is quite a bit of time and effort to get an engine that is exactly the same if 8-10 HP faster than when the car last ran.

I have been looking into the 4.9L swap, and it definitely more of what I want, over the 3.8 as it costs less, and a V8 sound is what I want. Plus the weight is only about 10 pounds more than the stock Fiero with double the HP and almost triple the torque.

My question to the noble and wise fiero gods is this:
I want to be able to buy all the parts needed for the 4.9L swap. I can pull an engine from a yard and it will cost $230. I have found a page here: https://johns49performance.com/why-49.html which sorta breaks down what is needed, but it isn't exact. I also can't seem to find a definitive swap on the 4.9L in the Fiero. I do know that the wiring harness does take the most time, and it is required to read a schematic in order to get the wiring harness done. Is there a vendor that people use to get their 4.9L parts? What is everything that I should pull from the car to be able to get this accomplished? Is there someone that I can basically purchase everything from in order to get the swap done, and maybe someone I can also pay to do my wiring harness as well? I tried to check the link for johns49performance, but I unfortunately don't see anything to buy other than a distributor.

My car is an 86GT with the 4 speed Muncie.

Thank you for the advice ahead of time.
Rickady88GT NOV 04, 10:52 PM

quote
Originally posted by zzzhuh:

It has been a long time since I've been on the forums, and I'm glad to be back. I hope everyone is out there staying safe during all of the madness that 2020 has caused.

My 2.8L Fiero hasn't ran in 3 years, due to moving as well as not having the time to replace the water pump. It currently does start and run, but I obviously don't run it for very long due to no coolant currently being in the car.

I am looking to replace the following things, which I currently have already purchased:
-Water Pump.
-Exhaust manifolds (I also want to port them and put new FelPro gaskets in)
-Rear Struts (I got KYB's)
-Slave Cylinder (Rodney Dickmans)
New coolant
New brake fluid and clutch fluid

With these things in mind, it seems that the best way forward is to remove the engine entirely, as I will be able to get to all of the bolts for the water pump, and I don't risk the same problem with those bolts that hold on the exhaust manifold. I figure that while the engine is out, I replace the valve cover gaskets, and it seems that there is black grim near the middle intake manifold under the red 'Fiero' Plenum, which means it could have been the valve cover, or worse.. The lower intake manifold gasket.

If I go this route, that is quite a bit of time and effort to get an engine that is exactly the same if 8-10 HP faster than when the car last ran.

I have been looking into the 4.9L swap, and it definitely more of what I want, over the 3.8 as it costs less, and a V8 sound is what I want. Plus the weight is only about 10 pounds more than the stock Fiero with double the HP and almost triple the torque.

My question to the noble and wise fiero gods is this:
I want to be able to buy all the parts needed for the 4.9L swap. I can pull an engine from a yard and it will cost $230. I have found a page here: https://johns49performance.com/why-49.html which sorta breaks down what is needed, but it isn't exact. I also can't seem to find a definitive swap on the 4.9L in the Fiero. I do know that the wiring harness does take the most time, and it is required to read a schematic in order to get the wiring harness done. Is there a vendor that people use to get their 4.9L parts? What is everything that I should pull from the car to be able to get this accomplished? Is there someone that I can basically purchase everything from in order to get the swap done, and maybe someone I can also pay to do my wiring harness as well? I tried to check the link for johns49performance, but I unfortunately don't see anything to buy other than a distributor.

My car is an 86GT with the 4 speed Muncie.

Thank you for the advice ahead of time.



The 4.9 is a good swap. Dont listen to the hate.
Rickady88GT NOV 04, 10:56 PM
The 4.9 is a good engine and a great swap in the Fiero IF you are realistic about your goals. The 4.9 is NOT a race car engine but is a powerful plant compared to the 2.8.
zzzhuh NOV 04, 11:29 PM

quote
Originally posted by Rickady88GT:

The 4.9 is a good engine and a great swap in the Fiero IF you are realistic about your goals. The 4.9 is NOT a race car engine but is a powerful plant compared to the 2.8.



I agree. I don't intend on the car being a power house, and I intend on changing the valve cover gaskets, as well as oil pan gaskets and checking everything out, but not doing anything crazy if I get the 4.9. My goals is to have a car that sounds good, and is simply a bit more than the 2.8. I know the 3.8 Series 2 pretty well, as I have a Buick Park Ave, as well as a Grand Prix GTP. I know it is more documented, but the 4.9 just makes more sense for me. I will be doing the basics of getting the engine to run in the car, and later down the road maybe I can find an allante intake to install, but that comes later.


Hopefully there are people on the forums here that can guide me to people that build the brackets and any additional things needed to accomplish this swap.

[This message has been edited by zzzhuh (edited 11-04-2020).]

Will NOV 05, 08:39 AM
A 3.4 iron head swap would give you extra oomph and be very very easy.

A 4.9 swap will give more oomph than that, but won't be anywhere close to twice the stock power and three times the stock torque. The 4.9 is rated for 50% more power than the 2.8 and 60% more torque.
Twice the stock WHP would be about 220-230 RWHP, and multiple builds on this forum have demonstrated that the 4.9 needs a good bit of work to get to that number.

I'm not saying a 4.9 isn't what it is, but it definitely is not what it isn't.

[This message has been edited by Will (edited 11-05-2020).]

sourmash NOV 05, 08:40 AM
Plus you can sing, "She's real fine, my 4.9."
Raydar NOV 05, 10:01 AM
Ask oldjoedad about a harness. I think he builds them for 4.9s.

John's 4.9 is on here. Might send him a message and ask what he has available. (I forget exactly how his screen name is spelled. And in PMs it matters. )
Warlordsix NOV 05, 12:28 PM
"The 4.9 is rated for 50% more power than the 2.8 and 60% more torque."

Right, but what makes a 4.9 Fiero such a tremendous, well-balanced, well-mannered, good-handling, quick and fun-to-drive car is a function of much more than those numbers. First, is the powerband of the 4.9...its torque (275 lbs/ft it's vs 170 lbs/ft of the 2.8) comes in under 3000 RPM compared to the 2.8 which comes in at 3600 RPM. Second is the weight of the entire swapped package, which is no heavier than the stock 2.8 Fiero. The result is instant response on the street....a fun-as-hell low-RPM shove in the back whether sprinting between stoplights or passing another car. To me the 4.9 Fiero is a great, practical combo for real world daily driving. Mine is a perfectly reliable daily driver, and it is a rare drive when someone doesn't compliment the car.

And if it's the V8 sound you like, then you won't be disappointed . A 4.9 with the Flowmaster I have on mine makes a deep, muscular rumble that is quiet at idle/cruise but thunders when you put your foot into it. I've got a neighbor with a '67 Shelby GT350 that swears my 4.9 Fiero sounds like our other neighbor's Viper when I drive by.

So, just do the 4.9 and don't sweat it. You'll have a blast with it on the street.

Ernie

------------------
'87 Fiero 4.9 5-speed

Neils88 NOV 05, 01:23 PM
The 4.9 is a relatively easy, low cost swap that will be guaranteed to put a smile on your face. There isn't anything in the swap that is particularly difficult for someone with average mechanical skills.

Hopefully you've searched on PFF for the many great threads that document the build. Here's a link to my thread, which also has links to other good 4.9 builds.

http://www.fiero.nl/forum/F...2/HTML/129733-1.html
zzzhuh NOV 05, 03:26 PM

quote
Originally posted by Will:

A 3.4 iron head swap would give you extra oomph and be very very easy.

A 4.9 swap will give more oomph than that, but won't be anywhere close to twice the stock power and three times the stock torque. The 4.9 is rated for 50% more power than the 2.8 and 60% more torque.
Twice the stock WHP would be about 220-230 RWHP, and multiple builds on this forum have demonstrated that the 4.9 needs a good bit of work to get to that number.

I'm not saying a 4.9 isn't what it is, but it definitely is not what it isn't.




I mainly plan on a simple swap. I will be taking the engine, and doing whatever is needed to get it into the car and running reliably. Additional mods such as an Allante intake, new cam, etc won't be in the additional build... But possibly may come later down the road.