im looking at my future swap...I was settled on the 3.4 pr due to its relative ease. But my eye has been wandering towards the dohc...my question to you is this...( yes I have searched ) what more is there involved with swapping in the dohc 3400 to a 86 notchback with the izuzu 5 speed and no options. I plan to put a turbo on either one i swap in.
Either will be rather temporary ( not sure how long it'll be temporary but in the future i plan to do a northstar swap )
Any info etc will be greatly appreciated thank you.
------------------ Cliff's 610th Positive Feedback Giver. #12 NYFOC Member In recent times, the custom aftermarket car/automobile roadwheel has become a status symbol. These wheels are often incorrectly referred to as "rims". The term "rim" is incorrect because the rim is only the outer portion of a wheel (where the tire is mounted
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11:15 PM
PFF
System Bot
fieroguy123 Member
Posts: 1523 From: Indianapolis Registered: Sep 2009
First of all, you're going to blow that isuzu in half with either engine. So get a getrag. Second of all, you're going to blow that isuzu into 800 pieces with a turbo 3400. So get a getrag.
But id say don't do the 3.4 dohc swap if ur planning on it being temporary fo the n*
if that's the case I'd just do the 3.4 pr then, seeing as how u don't have to change anything with wiring or mounting. Just a hole drilled to relocate start and the fiero 2.8 accesories switched over. Easier, less money, yet still a nice little up in horsepower and torque.
Adding a turbo will cost some money tho. I wouldn't do it personally if u plan on trashing it for a n* anyway
But id say don't do the 3.4 dohc swap if ur planning on it being temporary fo the n*
if that's the case I'd just do the 3.4 pr then, seeing as how u don't have to change anything with wiring or mounting. Just a hole drilled to relocate start and the fiero 2.8 accesories switched over. Easier, less money, yet still a nice little up in horsepower and torque.
Adding a turbo will cost some money tho. I wouldn't do it personally if u plan on trashing it for a n* anyway
exactly what i needed thank you. I have the turbo already which is why I would like to put it on.
I was also tryin to decide between the 3.4 pr and dohc, and I would also turbo whichever one I chose. I haven't 100% decides but leaning toward the dohc because of the much much much higher potential, because for me it will be a permanent swap. The maitenence for the dohc seems like it might be a little irritating (timing belt).
But ya like I said the pr might be better for u tho because it will just be a quick an dirty temporary swap
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12:46 AM
Blacktree Member
Posts: 20770 From: Central Florida Registered: Dec 2001
With a later model 3400 / 3500 V6, you get power similar to the 3.4TDC without the extra ~75lb bolted to the top of the engine... and no timing belt to snap. Just a thought.
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01:00 AM
Hockaday Member
Posts: 2165 From: Clifton Park, New York, The States. Registered: Sep 2009
With a later model 3400 / 3500 V6, you get power similar to the 3.4TDC without the extra ~75lb bolted to the top of the engine... and no timing belt to snap. Just a thought.
I haven't ever seen anyone make as much hp outta a 3400 or 3500 as a 3.4 dohc. 400-450 hp isn't farfetched for a turbo 3.4 dohc
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01:07 AM
Hockaday Member
Posts: 2165 From: Clifton Park, New York, The States. Registered: Sep 2009
With a later model 3400 / 3500 V6, you get power similar to the 3.4TDC without the extra ~75lb bolted to the top of the engine... and no timing belt to snap. Just a thought.
hrmmm...not as easy install as the camaro 3.4 is it? ( then again you might be talking about same engine lol )
Just to clarify engine terms so we are all talking about the same thing:
The "3.4 pushrod" generally refers to the iron-head 3.4 pushrod V6 used in the 93-95 Camaros and Firebirds (aka: 3.4 OHV).
The 3.4 TDC / DOHC (NOT 3400 DOHC) is the 4-cam V6 monster used in 1991-97 Luminas, Cutlass Supremes, Grand Prix's, and Monte Carlos. I have a detailed page-by-page swap posted here: http://www.gmtuners.com/Cus....4DOHCFiero/swap.htm
The 3400 is the aluminum head, roller cam, 3.4L displacement pushrod V6 that GM first came out with in 1996-up vehicles and was primarily used in minivans as well as some other cars. Makes more power than the 3.4 iron-head but less than the 3.4 DOHC.
-ryan
------------------ 7+ years on this same swap -- NO engine or transmission failures... Custom GM OBD1 & OBD2 Tuning | Engine Conversions & more | www.gmtuners.com
Just to clarify engine terms so we are all talking about the same thing:
The "3.4 pushrod" generally refers to the iron-head 3.4 pushrod V6 used in the 93-95 Camaros and Firebirds (aka: 3.4 OHV).
The 3.4 TDC / DOHC (NOT 3400 DOHC) is the 4-cam V6 monster used in 1991-97 Luminas, Cutlass Supremes, Grand Prix's, and Monte Carlos. I have a detailed page-by-page swap posted here: http://www.gmtuners.com/Cus....4DOHCFiero/swap.htm
The 3400 is the aluminum head, roller cam, 3.4L displacement pushrod V6 that GM first came out with in 1996-up vehicles and was primarily used in minivans as well as some other cars. Makes more power than the 3.4 iron-head but less than the 3.4 DOHC.
-ryan
THANK YOU! I know it's stupid... but little things like that make me want to pull my hair out.(what little there is left)
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07:34 AM
Hockaday Member
Posts: 2165 From: Clifton Park, New York, The States. Registered: Sep 2009
First of all, you're going to blow that isuzu in half with either engine. So get a getrag. Second of all, you're going to blow that isuzu into 800 pieces with a turbo 3400. So get a getrag.
Really, because I have not. My Isuzu had 69K on it when I attached it to my 96 DOHC and its fine. and yes I do "get on it". What proof do you have that it will blow up?
use the search and type "3.4 DOHC" you will find a bunch of my questions during my swap.
Bottom-line. These two motors are at different ends of the spectrum. What kind of driving do you plan to do with it when you’re done?
If you take a stock 3.4PR, drill the holes for the starter, do all the other things needed to fit the motor in, you end up with a 160hp motor. It will take some cash and time.
If you install the 3.4 DOHC you will end up with a 215+ HP motor that screams up to 7200rpm and sound awesome. YES, it is more work, and more cash, but in the end, of the two (3.4 pr and 3.4 DOHC) the DOHC motor may be better for you needs. Installing the DOHC motor is easy, the block is the same (external) as the 2.8L V6, so hooking it up to the trans and using the stock V6 motor mounts/trans mounts is a breeze. Yes you have to do some cutting, the pass side hood hinge and maybe your dogbone mount (some do, some don't) but other than that its easy. Wiring can be a challenge, but I did it so anyone can.
Of the two, the 3.4 PR is an easier swap, as a lot of the 2.8L parts will work, but you will still have some issues with wiring and the ECM. You will also have these issues with the 3.4 DOHC swap. You will have to figure out the exhaust and play around with fuel lines, and hoses and such.
Both swaps have +/- and both will cost you some $$$ and time. Its up to you what you want in the end.
Rob
.
------------------
88 Coupe, CJB T-TOP, 1996 3.4 DOHC and a GT clip
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09:51 AM
FieroReinke Member
Posts: 1065 From: St James, MO Registered: Feb 2003
If you want the northstar, then wait for the northstar. All the money and time you put into the 3.4 swap, either one, will be wasted. Just save the money and build a better northstar swapped car.
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01:46 PM
Dennis LaGrua Member
Posts: 15762 From: Hillsborough, NJ U.S.A. Registered: May 2000
A 3.4L DOHC engine will bolt right in (with very minimal mods) The N* is a ton of work to swap in. With a turbo and a 3.4L DOHC or TDC engine you can make lots of horsepower but I am not sure how reliability will factor in with the boosting and the 2 bolt mains. The 3.4L TDC is a very tight fit around the massive 4 valve heads and good plumbing skills are required to get a turbo properly positioned . The 3.4TDC is also the heaviest V6 that weighs in at around 492.5 lbs.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
[This message has been edited by Dennis LaGrua (edited 07-30-2010).]
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02:46 PM
PFF
System Bot
Doug85GT Member
Posts: 9831 From: Sacramento CA USA Registered: May 2003
Why do a "temporary" engine swap? While you are driving your 3.4 DOHC or 3.4 PR car and you are gathering parts of the N* swap, you can also buy another Fiero to do the N* swap in. After the N* swap you will have two engine swapped Fieros and you can keep both or sell one.
I just don't see why you would go through all the trouble of an engine swap just to rip it all out and do another one.
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03:46 PM
Doug85GT Member
Posts: 9831 From: Sacramento CA USA Registered: May 2003
A 3.4L DOHC engine will bolt right in (with very minimal mods) The N* is a ton of work to swap in. With a turbo and a 3.4L DOHC or TDC engine you can make lots of horsepower but I am not sure how reliability will factor in with the boosting and the 2 bolt mains. The 3.4L TDC is a very tight fit around the massive 4 valve heads and good plumbing skills are required to get a turbo properly positioned . The 3.4TDC is also the heaviest V6 that weighs in at around 592.5 lbs.
Wow! That engine gets heavier every time I look. When I had one shipped to me by R&L shippers, it was weighed as 480# shrink wrapped, strapped to a pallet on top of a tire.
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03:50 PM
Hockaday Member
Posts: 2165 From: Clifton Park, New York, The States. Registered: Sep 2009
because a duke fiero is slower then a mini van...northstar will be years down the road i figure. since im working on my trans am w/e i can...plus college is comeing up and jobs are impossible to find...but i might just do a northstar swap right away and drive my Zed. not really sure.
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04:40 PM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
Originally posted by Doug85GT: Wow! That engine gets heavier every time I look. When I had one shipped to me by R&L shippers, it was weighed as 480# shrink wrapped, strapped to a pallet on top of a tire.
Its all in Dennis mind
Mine weighs 465 lbs dressed
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05:22 PM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
Originally posted by Doug85GT: Wow! That engine gets heavier every time I look. When I had one shipped to me by R&L shippers, it was weighed as 480# shrink wrapped, strapped to a pallet on top of a tire.
Weight corrected. The engine weighs 492.5 lbs. When you add the weight of the flywheel you'll be close to your figure. Still the heaviest of the V6 engines though.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
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06:21 PM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
Weight corrected. The engine weighs 492.5 lbs. When you add the weight of the flywheel you'll be close to your figure. Still the heaviest of the V6 engines though.
wrong again ..the weight is 465 lbs dressed including a 12 lb flywheel and ..its very close to the weight of a 3800 SC
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06:44 PM
ltlfrari Member
Posts: 5356 From: Wake Forest,NC,USA Registered: Jan 2002
I never had a problem with the DOHC and a suzzy 5 speed tranny. Mind you I didn't do scream the engine and drop the clutch starts either. As for the weight, I never really noticed the extra weight back there. You do have to cut the bottom of the passenger side deck lid mount though to clear the cam cog cover on the front bank.
For a temporary swap I wouldn't do it. Too much work to just throw it away later. I think a pr motor would be a better option if you are going to replace it later anyway.
I think after we do a swap, its easy. I know that I could do another DOHC swap in a "virgin" fiero in a few months, but I have already done it, so I know all of the issues. I went from a 2.5 tech IV to the DOHC, so i noticed the power over the weight. Honestly, I don't even notice the motor weight. I have lowered the suspension, put on tight springs/shocks, added swaybars and POLY on all four corners, so when I finally got the swap done, and took it for a drive it was a totally differant car.
We can't tell you what to do, but you can learn from our mistakes. If I could do it all over again, and it was 6 years ago, id be dropping in an LS2/3 with a 6 speed. Yes, way more money, but after driving my 05 GTO for the last 4 years, I really want a LS motor in my car.
SO, I totally understand doing a swap, and doing another one soon after. If I had problems with this swap id be looking at upgrading now, but because it drives so well, im going to drive it for a few years.
temporary swap
