hello, I am a recent builder of a 85 gt with a longitudal mount 350. It runs and drives great so why are there so few??? Is there a fatal flaw that i have not found yet?

So what did you have to do? Did you lose your trunk? Did you have to use a three-speed Toronado slushbox transmission, or did you go with a manual Porsche unit? What did you do for an exhaust system?

For effort expended versus result achieved it's hard to beat a transverse installation, assuming you're running a stock-length Fiero frame. But if you go with a lengthened Fiero chassis, ALA kitcar, then a longitudinal installation starts making more sense.

I am using a three speed but it's no "slushpup" it's been rebuilt with a modified valve body . Yes i lost the trunk but i don't have any slipped clutches or broken axles. I do have alot of body flex so the windshield is always breaking

i dont think there too popular for the simple fact that a standard 350 will pretty much bolt right in with an archie kit and is a Verry easy swap to do(carbed ) and there is PLENTY of room in the engine bay once you get all the un needed crap out of there
here is a pic of one i built and have now sold
355 fully built, with a 4 speed manual trans

[This message has been edited by $Rich$ (edited 11-03-2005).]

I take it the engine is up front? I don't think I would ever even want to consider doing that. Why not just get a front engine car if you're going to do that?

It's been done by some other people on the Forum, the problem with the swap is that it doesn't corner worth crap. If you only care about "straight line" performance, it's a nice swap.

quote Originally posted by California Kid: It's been done by some other people on the Forum, the problem with the swap is that it doesn't corner worth crap. If you only care about "straight line" performance, it's a nice swap.

That's a pretty broad statement with nothing really holding it up. I'd say it's true concerning some of the swaps using the TH-425.

Concerning an aluminum LSx motor in front of a Porsche transaxle? Probably complete BS.
http://factoryfive.com/images/photos/gtm/3608.jpg

Nate

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My Web page | The Turbo Super Duty Build.
You know that little voice that says it can't be done? I duct-taped mine's mouth shut and pushed it down a flight of stairs.

My GT had a longitudal 350 when I got it.It weighed 3400 lbs.2200 on the rear and 1200 on the front.It didn't handle very well.If the engine were reversed(Facing the rear)there would be better weight distribution.

do a search on cardealer.
He has done it and used the caddy tranny. you MUST strengthen the frame!! ( oh and the wheelie bars DID help )

Straight line was the only way he could go without breaking a ball joint or two....

quote Originally posted by FastIndyFiero: That's a pretty broad statement with nothing really holding it up.

Nothing holding it up??? Been here a very long time, the only one running that I've seen done on Pennocks correctly for handling is RRunner's, and it's strictly a race car. The Factoryfive car you posted isn't even Fiero based. This issue has been discussed many times, and to do it correctly with most common power plants, you must stretch the chassis, to make an excellent handling car (same as the Fiero) it's going to cost a ton of money. Nobodies gone there yet to my knowledge.

I know ther is a huge weight distribution front to rear diference compared to stock v6. I have not been to a autocross race and don't intend on ever going. I have driven it almost 1500 miles mostly on the street. I have a rear sway bar and 550 lbs/inch rear springs. It's very stiff but there is no body roll. With 265/45/17 out back the rear has never spun out around a corner that i did not want it to. mine handles very simular to a stock v6. My plan was to try out the car and work out the bugs with a mild 350. Once it's all worked out and including $$ i will put in a aluminum block 377 with 6-71 blower and 300 hp nos.

quote Originally posted by California Kid: to do it correctly with most common power plants, you must stretch the chassis, to make an excellent handling car (same as the Fiero) it's going to cost a ton of money.

Hmmm,
I've got a '94 LT1 mated to a thm325. The cradle had to be stretched, but not the cradle to chassis mounting points. And certianly not the chassis. The stretch is to the rear, and with the cradle only. Although I built this originally to go into a 10.5" stretched Diablo chassis....It wil fit into a stock Fiero chassis. The only thing lost is a portion of the trunk.

The reason I even started this conversion was it's comparitively low cost.

What I really like about the setup is that you can put your pedal to the metal, without leaving a bunch of transmission or axel parts in the road.

David Breeze

[This message has been edited by opm2000 (edited 11-03-2005).]

quote Originally posted by opm2000: What I really like about the setup is that you can put your pedal to the metal, without leaving a bunch of transmission or axel parts in the road.

Me neither.

I would love to see pics of a longitudinal V8 in front of the transaxle without stretching the chassis. If you don't stretch the chassis, your only option to my knowledge is to have the engine aft of the transaxle, which will give you a serious rear weight bias.

Even with the extra weight of an iron V8 or 3800SC swap, if it's done transverse, the bulk of the weight stays mid-mounted (in front of the drive axle). Once you move the weight behind the rear wheels, it's detrimental effect on handling goes up dramatically.

Weclome to the forum, buildamonster!

Got any pics of your car, and the setup?

quote Originally posted by buildamonster: hello, I am a recent builder of a 85 gt with a longitudal mount 350. It runs and drives great so why are there so few??? Is there a fatal flaw that i have not found yet?

Yea.. I want to see pictures too

There isn't much info on longitudinal swaps... It's been done, but as mentioned the transverse swap is much easier.. There is one member on the forum that's doing a longitudinal Cadillac Northstar build.. You can follow it here: https://www.fiero.nl/forum/Forum1/HTML/033676.html

quote I would love to see pics of a longitudinal V8 in front of the transaxle without stretching the chassis. If you don't stretch the chassis, your only option to my knowledge is to have the engine aft of the transaxle, which will give you a serious rear weight bias.

You're obviously not familiar with the TH325 and TH425 transaxles. You're thinking of a typical porsche/audi/VW transaxle. Here is a picture that shows the engine in front of the trans and just how much of the engine is still behind the axles.

More picts.

By turning it around and putting the engine behind the trans you actually get more of the engine and all of the trans in front of the axles. It will fit either way without extending the chassis.

I was happy with my TPI 350/TH325-4L, but I never drove it hard, the body was too pretty. Been thinking lately that I'd like to do it again.

Porsche/chevy:
https://www.fiero.nl/forum/Forum1/HTML/048610.html

I have lots of digital picture. I just don't know how to post pictures.

At the bottom of any forum page is a red and blue box that is a link to the Pennocks Image Poster. It will download the software so you can use it to post pictures. It can be a little tricky until you use it a few times-you can do a search on the forum for PIP to learn more.

Hulk

Edit: Welcome to the forum!

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86 Fiero GT
-Stage eleventy billion...

04 Mustang Cobra
-K&N FIPK (first mod, woo-hoo!)

[This message has been edited by Hulk (edited 11-03-2005).]

quote Originally posted by revin:

Boooiiiiinnnnnnnnnnnngggggggggggg! Holy Cow!

quote Originally posted by F-I-E-R-O: Boooiiiiinnnnnnnnnnnngggggggggggg! Holy Cow!

You Can Say That Again
so much for the rear view though.

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Soon to be custom port fuel injected with Megasquirt! 4.5l and th-440 And Im only 18. think about when Im 30!!

quote Originally posted by California Kid: Nothing holding it up??? Been here a very long time, the only one running that I've seen done on Pennocks correctly for handling is RRunner's, and it's strictly a race car. The Factoryfive car you posted isn't even Fiero based. This issue has been discussed many times, and to do it correctly with most common power plants, you must stretch the chassis, to make an excellent handling car (same as the Fiero) it's going to cost a ton of money. Nobodies gone there yet to my knowledge.

quote Originally posted by California Kid: the problem with the (350 longitudinal) swap is that it doesn't corner worth crap.

So do it correctly. Stretch the chassis and focus on handling. All you're saying is that it's a bad swap because no one does it right...

Like I said, a broad statement that you attempt to apply to future swaps when you have NO idea if someone is going to do it "right" or not.

quote Originally posted by FastIndyFiero: So do it correctly. Stretch the chassis and focus on handling. All you're saying is that it's a bad swap because no one does it right... Like I said, a broad statement that you attempt to apply to future swaps when you have NO idea if someone is going to do it "right" or not.

Then you've completely mis-read the Poster's original questions;

"It runs and drives great so why are there so few???" and this "Is there a fatal flaw that i have not found yet?" and this "I am using a three speed but it's no "slushpup" it's been rebuilt with a modified valve body . Yes i lost the trunk".

He's asking about his setup, which is what I responded to. He didn't ask "What is the proper way to do it and maintain same or better corning performance" which is what you're trying to turn this thread into.

Can a longitudal V8 be done with excellent performance results ? Answer; Sure it can, but as I stated in an above post, no one on this Forum has done it yet with proven results, and I don't consider stretched re-bodied cars to hold their original name of Fiero. The fact of the matter is that there aren't that many people who are willing to go the lenghts and expense on a 20 year old car, that's why it's not more popular.

As far as I'm concerned, my debate with you is over on this matter.

[This message has been edited by California Kid (edited 11-04-2005).]

quote Originally posted by rockcrawl: You're obviously not familiar with the TH325 and TH425 transaxles. You're thinking of a typical porsche/audi/VW transaxle. Here is a picture that shows the engine in front of the trans and just how much of the engine is still behind the axles. More picts. By turning it around and putting the engine behind the trans you actually get more of the engine and all of the trans in front of the axles. It will fit either way without extending the chassis. I was happy with my TPI 350/TH325-4L, but I never drove it hard, the body was too pretty. Been thinking lately that I'd like to do it again.

Awesome! I was aware of the TH425, but not the others. Even so, I didn't think there'd be enough room to do it, unless it was the other way around with the engine facing aft. Very nice.

quote Originally posted by California Kid: Then you've completely mis-read the Poster's original questions; "It runs and drives great so why are there so few???" and this "Is there a fatal flaw that i have not found yet?" and this "I am using a three speed but it's no "slushpup" it's been rebuilt with a modified valve body . Yes i lost the trunk". He's asking about his setup, which is what I responded to. He didn't ask "What is the proper way to do it and maintain same or better corning performance" which is what you're trying to turn this thread into. Can a longitudal V8 be done with excellent performance results ? Answer; Sure it can, but as I stated in an above post, no one on this Forum has done it yet with proven results, and I don't consider stretched re-bodied cars to hold their original name of Fiero. The fact of the matter is that there aren't that many people who are willing to go the lenghts and expense on a 20 year old car, that's why it's not more popular. As far as I'm concerned, my debate with you is over this matter.

I did not mis-read the poster's question, nor did I attempt to give him an answer. Your first post simply made it sound like all longitudinal swaps don't handle well, which I contest.

To one thing I agree, to debate this any more is silly.

Nate

So you just took it upon yourself to clutter up his thread !!!

thanks for all the great info

[This message has been edited by buildamonster (edited 11-05-2005).]

Wow! That thing is beautiful. Yours too Revin. Awesome!
You longitudinal guys have my full respect.

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-Rick Stewart
85GT 5.0CaddyV8/Getrag 5-spd in progress...
www.V8Fiero.com

The Longitudal V8 install can prove to be a reliabale swap as the engine and transmission are very compatible. I've seen a Fiero with this swap run in the 12's (1/4 mile) so they can be fast as well. However, I do believe that the handling of Fieros with this swap will leave much to be desired and you must completely eliminate what little trunk space there is.

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87GT 3.4 Turbo- 0-60 5.2 seconds -Best
Engine Controls, ECM goodies, Chip
re-programming & odd electronics stuff

is there a tutorial or somthing to show how to build one of these.... like lectrical diagrams. Also is there any standard FWD long. gm trannies ?

quote Originally posted by revin:

Now that is what a V8 in a Fiero should look like I love black Fieros. I have to say I had a V8 Archie kit with a SBC in my 86 car and hated it. The solid mount makes the car shake and the car did not handle good any more after a week I pulled it all out and went a different wrought I would think that having the SBC sitting in the center of the car would be better as it is the way Ferrari does their V8s. This is my opinion from actually having one and driving it. I have not had a logitudal V8 so I have no Idea how it would handle. After seeing the pictures it looks better. Hats off too you for making it work and look like a dream.

[This message has been edited by F355spider (edited 12-18-2005).]

How much would that engine/trani combo weigh? Thats one of the only downsides I can see.

Very nice car!

Heres a site on it, http://www.fieroaddiction.com/SBCLa.html

the guy says that a "reverse rotation" with the trans in front of the engine has a better weight distribution

quote The Reverse Rotation Option After I had already started my conversion, I found out that it can be done differently to better distribute the weight. By rotating the entire engine/trans 180 deg so that the pulleys are at the back of the car, you can get a lot more of the weight in front of the rear axle. The differential housing then needs to be rotated 180 deg to an upside-down position to make the axles turn the opposite direction. This also places the pinion shaft below the axle centerline, effectively lowering the engine. I have never done a swap this way, so I can only speculate what changes must be made. First off, the tie rods can probably stay where they are. Also, the trunk may be able to be retained, or at least more of it. I would expect that the oil pan modification would be more extensive. If I were to do another longitudinal swap, I would definitely do a reverse rotation due to the weight distribution advantages.

I have one that was NOT done correctly. I'm glad to say I didn't
do it. The car is extremely tail heavy and waves its tail like a
prissy school girl. My future plans are to reverse the rotation (it has a TH325),
and move more weight forward. If not done better, this car is very dangerous to
drive.

Buildamonster, I like the clean look your car has, inside and out. Nice ride.
I was wondering if you could gain anything by finding a way to brace the shock
towers, since the cut trunk eliminates the sheet metal tie-in from side to side.
Maybe an angle brace from the shock towers to the back of the car and then a cross
brace clearing the dist. This is an issue I'll have to solve on my "sleeper".
TG

Eh Buildamonster

Welcome to the club.eh nice pics..now do u have any planes to turn the engine and trans 180 degree's..if u do u will add more weight to the centre of the car for better handling..also what i did was to use a 13mm adaptor plate on the diff to flip it and to push the alxes more to the back so to add more weight to the centre..but in the case i am allways looking to loss weight so i did not go with a 350 or V12 bmw..but i did pick up a neat little engine to really have fun..also i trying to use everything alumuim to save weight

Nice to finally hear from some longitudinal guys. I was looking for the longest time for some info on "your kind" of swap. I could'nt find enough info and was a little worried about doing the swap "blind".

I was a diehard Olds Guy and had a few Toronados w/ 455's (In fact, 1 of the 455's , now 467cid is in my 79 T/A). Nothing like a high 11 second FWD 66 Toro. The TH425 is a real workhorse and I've even seen quite a few hopped op TH325-4L overdrive transaxles behind 400+ HP motors and taking a beating very nicely. Does anyone have any detailed / closeup pics of your TH425 and Axle configuration. It was the one area that I thought may have been a little tight but certainly has proven pretty do'able that's for sure.

[This message has been edited by 3084me (edited 01-01-2006).]

quote Originally posted by rockcrawl:

At one time, the owner of this car, S.J. Wynman, had produced and was selling "Guidelines" for this install on CD. Don't know if they're still available.

Sorry for a slow response. I have been having too much fun driving around. One day i found my self at irp it's a 1/4 drag strip in indianpolis,in. My intention where to do a little tunning and have a lot of fun. My first run was 14.06@104mph with a flung water pump belt. After replacing the belt and some timing adjustment i ran 13.2@108mph. i think there is still more to be had. It's been a great car that is as reliable as it was new witha v6. I have not had any of the transvers mounting problems. ie.. burnt/broken clutches trashed transmissions and broken axles. I had planed on running out the bugs with this mild 350 and stuffing in a blower engine. But this one is great for a street driver. i am looking to buy a 88gt and build a roll cage to stiffen it all up. My windshield has a huge crack in the passenge side from body flex. I highly recomend not using a 325-4L transmission. I had one and did not like it. use a 425 if possible. As i have been told the 425 share's many parts with the 400 turbo so it's stong stock (500hp+) I have a 325 it's been worked over alot by a experience transmission guy. mine shift quick and hard but it's a manual valve body only. I think the reverse rotation is a great idea but i am alittle scared about flipping the "rearend" over because the oil/grease is not where it was meant to be. I do need a strut tower brace i have been holding off to put the blower in first then build one around that.