Pennock's Fiero Forum
  Technical Discussion & Questions
  Which engine for Fiero GT Fastback?

Post New Topic  Post A Reply
Email This Page to Someone! | Printable Version


next newest topic | next oldest topic
Which engine for Fiero GT Fastback? by Renier
Started on: 02-27-2015 06:58 PM
Replies: 12 (515 views)
Last post by: Renier on 03-09-2015 02:30 PM
Renier
Member
Posts: 28
From: Eindhoven, the Netherlands
Registered: Feb 2015


Feedback score: N/A
Leave feedback

Rate this member

Report this Post02-27-2015 06:58 PM Click Here to See the Profile for RenierClick Here to Email RenierSend a Private Message to RenierEdit/Delete MessageReply w/QuoteDirect Link to This Post
Dear people of the Fiero forum, I've only just subscribed as I'm going to be the proud owner of a Fiero GT Fastback tomorrow. But I would like to ask the question that has probably been asked many, many times before, yet in this case particularly for my situation as I thought some of you might not mind to chip in a little with your advice.

The Fastback has a Miller Wood Turbo kit, but the engine was blown up, the kit seems to have had everything but no oil cooler of intercooler... something I think is pretty important and I'd like to add if possible, maybe behind the airscoops it has on the side if that would work.

But my real question here is what engine should I replace it with? I'd be happy if I could reuse the turbo installation, and I'm certainly very tied to a low budget unfortunately but that's simply the way it is at my age (21). I've done engine swaps before, shouldn't be the problem, and besides there are many thorough guides out there for which I am utterly thankful. But what is a problem is picking just one engine. I was thinking it'd be best to go with a 3.4 from a early 90's Camaro or Firebird, since I could reuse everything, but on the other hand I heard that 3.4 DOHC swaps might be more profitable? What would work best with the turbo installation and what are the ups and downs of both options?

Many thanks in advance!

By the way, it seems that I can only find 3.4 DOHC's in Chevrolet Trans Sports here (in the Netherlands), would there be a disbenefit in getting one from such a truck as it's a truck and not a sportscar (tuned different maybe)? I did hear something about the ones in the transporters being of lesser quality, China-grade head gaskets for example.
IP: Logged
PFF
System Bot
no2pencil
Member
Posts: 1494
From: Baltimore, MD
Registered: Oct 2009


Feedback score: (3)
Leave feedback

Rate this member

Report this Post02-27-2015 07:08 PM Click Here to See the Profile for no2pencilClick Here to Email no2pencilSend a Private Message to no2pencilEdit/Delete MessageReply w/QuoteDirect Link to This Post
Welcome to the forum!

"Best" is a very relative term. I have a 3.4L (no turbo) & it's good for me. The 3800 seems to be more popular & better for the money.

Either eay you go, post lots of picture updates!
IP: Logged
unboundmo
Member
Posts: 2242
From: California
Registered: Sep 2006


Feedback score: N/A
Leave feedback

Rate this member

Report this Post02-28-2015 01:25 AM Click Here to See the Profile for unboundmoClick Here to Email unboundmoSend a Private Message to unboundmoEdit/Delete MessageReply w/QuoteDirect Link to This Post
I too went the 3.4L push rod out of a 95 camaro. I've prepped the engine with forged internals, everywhere ported and polished, 1.6 rollers and all the other goodies for a turbo or actually I wasthinking of a supercharger where the A/C went. A person in Canada did it... But also I'm in a us state where they have smog and look down on/ ticket or take away modified cars.. So I wanted the stock look of the engine if pulled over.. I did hear that the DOHC engine is best for the turbo app but I also heard that it is harder to tune for the turbo... For my engine, I assume I can piggy back the ecm and run off the 7th injector for boost.. Not sure hard hard it'll be to tune because I haven't ventured in it yet but seems to be attainable.

[This message has been edited by unboundmo (edited 02-28-2015).]

IP: Logged
Lou6t4gto
Member
Posts: 8436
From: sarasota
Registered: May 2008


Feedback score:    (7)
Leave feedback

Rate this member

Report this Post02-28-2015 01:35 AM Click Here to See the Profile for Lou6t4gtoClick Here to Email Lou6t4gtoSend a Private Message to Lou6t4gtoEdit/Delete MessageReply w/QuoteDirect Link to This Post
If you want to stay with the 60 degree 6, use the 3.4 , Not the dohc.
IP: Logged
Arns85GT
Member
Posts: 11147
From: London, Ontario, Canada
Registered: Jul 2003


Feedback score: (1)
Leave feedback





Total ratings: 200
Rate this member

Report this Post02-28-2015 11:14 AM Click Here to See the Profile for Arns85GTClick Here to Email Arns85GTSend a Private Message to Arns85GTEdit/Delete MessageReply w/QuoteDirect Link to This Post
I don't know if you can get the 3800 in the Netherlands. It is definitely the better candidate for the turbo.

We had one here in London that made 500 reliable hp with high test gas in it.

The 3800 is a very strong engine. Failing that, the 3.4 pushrod out of the 93-95 camaros is solid too, but won't make the hp the 3800 will
IP: Logged
Renier
Member
Posts: 28
From: Eindhoven, the Netherlands
Registered: Feb 2015


Feedback score: N/A
Leave feedback

Rate this member

Report this Post02-28-2015 04:40 PM Click Here to See the Profile for RenierClick Here to Email RenierSend a Private Message to RenierEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks, guys! Picked the Fiero up today, still didn't get much wiser but what I'm getting from this here is that which ever way I go could certainly work out if done right.

The thing with the turbo installation though is that I think it'll only be completely compatible with the 3.4 from an F-Body, for a DOHC which might be better (while a decent F-Body one would be a good choice as well) I'd need other things in order to run the turbo on it and on a 3.8 it will just plain not fit unless I get a special ECM and MAP sensor and etc. (may or may not be more than what's necessary for the DOHC).

Actually, I don't think the DOHC would run with the ECM, but then again I shouldn't get ahead of myself since I haven't had a chance to take a good look at the ECM yet... it might be programmeable for whatever, as far as I know. All I know is that it's a pretty old one, so shouldn't expect too much from it yet.



[This message has been edited by Renier (edited 02-28-2015).]

IP: Logged
hnthomps
Member
Posts: 5492
From: Columbia, SC
Registered: Jul 2003


Feedback score:    (18)
Leave feedback





Total ratings: 50
Rate this member

Report this Post03-01-2015 12:35 PM Click Here to See the Profile for hnthompsClick Here to Email hnthompsSend a Private Message to hnthompsEdit/Delete MessageReply w/QuoteDirect Link to This Post
If you want to keep the turbo the easiest swap (depending on engine availability) is the 3.4 push rod engine from the 93-95 Firebird/Camero. The turbo adds some pep and you can keep the turbo with this engine. I happen to have this combo and enjoy it. The HP will not be as high as a V8 or 3800 SC engine but the computer, most 2.8 engine parts, and existing wiring can be used. It is likely that you will need a custom chip to adjust fuel flow appropriately and larger than initial factory injectors (17 or 19 lb injectors are generally used).

Nelson
IP: Logged
Renier
Member
Posts: 28
From: Eindhoven, the Netherlands
Registered: Feb 2015


Feedback score: N/A
Leave feedback

Rate this member

Report this Post03-01-2015 02:51 PM Click Here to See the Profile for RenierClick Here to Email RenierSend a Private Message to RenierEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by hnthomps:

If you want to keep the turbo the easiest swap (depending on engine availability) is the 3.4 push rod engine from the 93-95 Firebird/Camero. The turbo adds some pep and you can keep the turbo with this engine. I happen to have this combo and enjoy it. The HP will not be as high as a V8 or 3800 SC engine but the computer, most 2.8 engine parts, and existing wiring can be used. It is likely that you will need a custom chip to adjust fuel flow appropriately and larger than initial factory injectors (17 or 19 lb injectors are generally used).

Nelson


Thanks for your reply, do you have an intercooler and/or an oil cooler and do you know approx. how much HP you are making with the combo?

More pictures: (we've also washed it and put it safe and secure inside of a hall )

This images is larger than 153600 bytes. Click to view.





This images is larger than 153600 bytes. Click to view.



[This message has been edited by Renier (edited 03-01-2015).]

IP: Logged
jediperk
Member
Posts: 588
From: Center of the Universe
Registered: May 2013


Feedback score: (2)
Leave feedback

Rate this member

Report this Post03-01-2015 04:31 PM Click Here to See the Profile for jediperkSend a Private Message to jediperkEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by hnthomps:

If you want to keep the turbo the easiest swap (depending on engine availability) is the 3.4 push rod engine from the 93-95 Firebird/Camero. The turbo adds some pep and you can keep the turbo with this engine. I happen to have this combo and enjoy it. The HP will not be as high as a V8 or 3800 SC engine but the computer, most 2.8 engine parts, and existing wiring can be used. It is likely that you will need a custom chip to adjust fuel flow appropriately and larger than initial factory injectors (17 or 19 lb injectors are generally used).

Nelson


IP: Logged
Steven Snyder
Member
Posts: 3311
From: Los Angeles, CA
Registered: Mar 2004


Feedback score: (2)
Leave feedback





Total ratings: 106
Rate this member

Report this Post03-02-2015 11:15 PM Click Here to See the Profile for Steven SnyderClick Here to visit Steven Snyder's HomePageClick Here to Email Steven SnyderSend a Private Message to Steven SnyderEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Renier:

By the way, it seems that I can only find 3.4 DOHC's in Chevrolet Trans Sports here (in the Netherlands), would there be a disbenefit in getting one from such a truck as it's a truck and not a sportscar (tuned different maybe)? I did hear something about the ones in the transporters being of lesser quality, China-grade head gaskets for example.


The 3.4 in the Transport is the 3rd generation version of the 2.8/3.1/3.4 pushrod V6. It's usually referred to as the "3400 V6". It has aluminum heads, but it's still a 2-valve pushrod motor, not DOHC. You can't put the Fiero heads and intake on the later 3.4 because the compression ratio will be very very low due to the different pistons.
IP: Logged
Renier
Member
Posts: 28
From: Eindhoven, the Netherlands
Registered: Feb 2015


Feedback score: N/A
Leave feedback

Rate this member

Report this Post03-03-2015 05:18 PM Click Here to See the Profile for RenierClick Here to Email RenierSend a Private Message to RenierEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks for the info!

Can't seem to get the trunk open, unfortunately, even after hooking up a battery and a lot of things do seem to work even after 6 years of having stood in a yard, and everything looks surprisingly and refreshingly mint upon closer inspection (relativiely speaking), much better than expected! I'm starting to fall quite in love with my Fiero GT I had no idea I'd feel such a way about the Fiero, hardly noticed it before (they're really quite rare here).

I think that the transmission needs to send out a signal that it's in park to get the trunk open, right? Well, without a transmission that's a little hard, and unfortunately while the other locks work the lock on the trunk doesn't. It works per a switch, or is supposed to, but the switch does nothing and I think there's a yellow wire that leads to the release motor but even applying 12v to it directly does nothing, not even a slight buzzing sound or anything. Is there a workaround or something I might be missing? Next thing I know I might have to end up drilling a hole in the lock :S wouldn't want to do that, but if it's the only way it's the only way I suppose... unless it isn't? Neither do I love the idea of having a separate key for the trunk.
IP: Logged
PFF
System Bot
Shho13
Member
Posts: 835
From: North Jersey
Registered: Feb 2014


Feedback score: (5)
Leave feedback

Rate this member

Report this Post03-03-2015 08:17 PM Click Here to See the Profile for Shho13Click Here to Email Shho13Send a Private Message to Shho13Edit/Delete MessageReply w/QuoteDirect Link to This Post
The deck lid not opening can be because it's technically on the same circuit as the "BRAKE" fault light on the dash. On the standard transmission, If the ignition is on then the "BRAKE" light has to be lit (It thinks the emergency brake is applied) for the deck lid to pop open under power IIRC. Not sure if it is a different setup for the automatic...

Also, check the fuses!

------------------
"Discord"
Red 1988 GT under restoration!

( ͡° ͜ʖ ͡°)

[This message has been edited by Shho13 (edited 03-03-2015).]

IP: Logged
Renier
Member
Posts: 28
From: Eindhoven, the Netherlands
Registered: Feb 2015


Feedback score: N/A
Leave feedback

Rate this member

Report this Post03-09-2015 02:30 PM Click Here to See the Profile for RenierClick Here to Email RenierSend a Private Message to RenierEdit/Delete MessageReply w/QuoteDirect Link to This Post
I've actually been offered a free but good condition 3.1L V6 from an Oldsmobile by a friendly local garage that I've occasionally worked with. Due to this I'm now seriously considering using that in combination with my turbo installation. What do you guys think? A 3800 series V6 would be totally amazing for sure, but a whole lot more expensive and waaay more (extra complicated) work, I'm certain. Consider me petty much having no money at all for anything like a 3800 series swap anyways.
IP: Logged

next newest topic | next oldest topic

All times are ET (US)

Post New Topic  Post A Reply
Hop to:

Contact Us | Back To Main Page

Advertizing on PFF | Fiero Parts Vendors
PFF Merchandise | Fiero Gallery | Ogre's Cave
Real-Time Chat | Fiero Related Auctions on eBay



Copyright (c) 1999, C. Pennock