My car is a 1987 GT 5 speed manual and has lost considerable amount of power do to that the catalytic converter has clogged up this past week. Now comes the part where the Fiero Factory comes in, when they do the swap do they use the donor cars catalytic converter or do I have to fix mine (purchase a new one) before the swap.

PS: if you are wondering why I haven't asked someone at the Fiero Factory, I tried calling them today but it seems the don't work on Saturdays which is okay I just need an answer fast.

Thanks

They will work with you. Every swap is (or at least used to be) a custom installation.
I used my original exhaust system including the cat.
They also build a "shorty" system that uses a new cat, but it's quite loud.

They might be able to install the engine without a cat if there is no cat on there when they receive it. "For off-road use only" of course.
Are you driving it to the Fiero Factory from Miami? It probably won't make it if the cat is already starting to clog up.

[This message has been edited by Raydar (edited 11-23-2013).]

quote Originally posted by Raydar: They will work with you. Every swap is (or at least used to be) a custom installation. I used my original exhaust system including the cat. They also build a "shorty" system that uses a new cat, but it's quite loud. They might be able to install the engine without a cat if there is no cat on there when they receive it. "For off-road use only" of course. Are you driving it to the Fiero Factory? It probably won't make it if the cat is already starting to clog up.

Most likely driving, so I guess I'll have to get a new one.

Thanks for you reply.

quote Originally posted by Raydar: I used my original exhaust system including the cat.

Does that have a large enough capacity for the 4.9? It seems to me that it would be restrictive....or does the V6 use a 2 1/2" pipe?

[This message has been edited by Neils88 (edited 11-23-2013).]

I should explain...
I had an Ocelot system with the stock cat. It was quite restrictive, in addition to the fact that it was just too quiet.
I ended up having a custom 2.5" system with a single outlet built. It consists of a high flow cat (3", adapted down) and an 18" glasspack with a C6 tip.
THAT one is just a bit too loud. Drones in the car at highway speeds. The cat and muffler are in the stock locations.

To directly answer the question, the V6 uses 1 7/8 - 2" pipe. The Ocelot isn't much, if any, larger.

[This message has been edited by Raydar (edited 11-23-2013).]

The stock Fiero system relies on too small a pipe to support the 4.9. I expect they don't use the Fiero cat.

Arn

The 4.9 collector pipe after the Y is 2.5" fyi

[This message has been edited by Arns85GT (edited 11-23-2013).]

The stock 2.5 setup on the '88 is only 2", so I've been building a complete new system using 2 1/2" pipe. I'm following the stock routing and using a slightly modified stock 4.9 crossover pipe to create the Y. I've seen lots of write-ups on exhausts (catalytic converter and muffler combinations) but nothing really jumps out as ideal (yet) as a good compromise between power and noise.

Useful chart for anyone designing their own system:

darn it, just bought a magnaflow cat 2in in 2in out. Do you think they will have to change it when the 4.9 is being installed?

quote Originally posted by 87GT2M6: darn it, just bought a magnaflow cat 2in in 2in out. Do you think they will have to change it when the 4.9 is being installed?

If you are putting the money into the swap, you'll want to get the right flow capacity. You could just replace the cat with a straight piece of pipe clamped in place for the drive...cheap option. Or...if you have access to a welder, cut the cat open, remove it's guts and reweld closed...really cheap option...

EDIT: ...are you sure your Cat is clogged?

[This message has been edited by Neils88 (edited 11-23-2013).]

quote Originally posted by Neils88: If you are putting the money into the swap, you'll want to get the right flow capacity. You could just replace the cat with a straight piece of pipe clamped in place for the drive...cheap option. Or...if you have access to a welder, cut the cat open, remove it's guts and reweld closed...really cheap option... EDIT: ...are you sure your Cat is clogged?

Had a mechanic check it out today and that is what he said. Barely any flow out the tips and a loud hissing sound when accelerating.

I got rid of the CAT when I had the V6 and of course no CAT with the V8.
As you know we do not have to put up with the money making (for the state) so just get rid of it.

quote Originally posted by LT188GT: I got rid of the CAT when I had the V6 and of course no CAT with the V8. As you know we do not have to put up with the money making (for the state) so just get rid of it.

I think I remember Ed saying something about having to comply with federal regs when they do their swaps.
He was pretty specific about what he could do when building exhaust systems. (i.e., running through the stock system, or using his custom system with the cat in the middle, with glasspacks on either side of a T, or something to that effect.)

I'm guessing that may supercede any expired state laws, but I could be wrong. Best just to ask.

quote Originally posted by Neils88: Useful chart for anyone designing their own system:

Just to be clear, this chart is for application on true duals only. The primary pipes on the headers are another chart, as is a single pipe like on the Fiero fyi

quote Originally posted by Neils88: Useful chart for anyone designing their own system:

That right there should tell you why most Fiero 3.4 swaps have a hard time breaking the 150rwhp barrier. I have a 2.5" exhaust and have made 187rwhp with my 3.4 ... which is more than a 4.9 makes. By contrast my 4.9 w/Allante intake made 170 rwhp on the same (Mustang) dyno.

Take my advice, do a proper 3.4 build and you'll have more power and more money in your pocket.

[This message has been edited by lou_dias (edited 11-24-2013).]

See where the chart says this:

quote NOTE: These numbers are just estimates

CFM that can flow through a fixed size of pipe is dependent on the pressure drop from each end. In a naturally aspirated engine, this chart might be somewhat accurate for intake pipe sizing, but it is woefully inaccurate for the exhaust side. Since the engine is upstream of the exhaust, and it is a positive displacement pump, it can force quite a bit more CFM through the exhaust than this chart, but it will see an increase in back pressure to do it.

For example, per the chart a single 3" exhaust has a max HP of 339. My LS4 dynod 382 whp and has close to 430 fwhp and has all the exhaust routed through a single 3" section of pipe prior to the single muffler. Now granted the 3" section of the exhaust is less than 12-18", but it is still there. It does have a 4" cold air intake though.

[This message has been edited by fieroguru (edited 11-24-2013).]

quote Originally posted by Raydar: They will work with you. Every swap is (or at least used to be) a custom installation. I used my original exhaust system including the cat. They also build a "shorty" system that uses a new cat, but it's quite loud. They might be able to install the engine without a cat if there is no cat on there when they receive it. "For off-road use only" of course. Are you driving it to the Fiero Factory from Miami? It probably won't make it if the cat is already starting to clog up.

Hey Raydar, question that is slightly off-topic, but not entirely:

when you had a fiero factory swap done, what chip did they use on yours, a modded one, or did they just use a VATS bypass with the stock module?

the reason i ask is that i have been getting ALOT of business lately from people who have problems with their 4.9L fiero factory installs, and a reprogrammed chip from me fixed the problems. It just makes me wonder what kind of programming they are doing, if any. I've seen a range of variables in the chips people have been sending me, from some that almost looked like exact copies of my chips, but had some of the variables sku'd or certain lines of code 'rem'ed out, to completely stock looking, but again, would have some bits of data missing all together, almost as if they were compiled with an application that doesn't do a checksum before it creates a bin file.

Anyways, i am curious to know where they get their chips. Honestly, its cool by me, because i get more business, but at the same time, it's sad that the fiero enthusiasts aren't getting the full potential from their swaps. I tried working a deal out with them a while back, doing chips at an absurdly cheap rate for them, and they weren't interested, even though my chips have a strong track record of success. it makes me think they are doing the programming themselves, and or just adding a bypass module to a stock chip and calling it a day. they don't realize there is a significant amount of room there to make some performance gains

[This message has been edited by stickpony (edited 11-28-2013).]

quote Originally posted by 87GT2M6: My car is a 1987 GT 5 speed manual and has lost considerable amount of power do to that the catalytic converter has clogged up this past week. Now comes the part where the Fiero Factory comes in, when they do the swap do they use the donor cars catalytic converter or do I have to fix mine (purchase a new one) before the swap. PS: if you are wondering why I haven't asked someone at the Fiero Factory, I tried calling them today but it seems the don't work on Saturdays which is okay I just need an answer fast. Thanks

my suggestion is this.. if you are going to take the time to go all the way up to the fiero factory from Miami ( south FL here, Coral Springs ), why not just get a new hi-flow cat?

also... something you really need for your swap since we are on the subject of catalytic converters, and this suggestion has saved people countless hours of troubleshooting why they are getting poor gas mileage --> not all O2 sensors are created equal, and there is a varying range of operational temperatures. MANY of the Fiero swaps done have the exhaust routed in such a way that the O2s don't consistently stay hot to give accurate readings. If you have them install heated O2s and wire in an extra relay and fuse for them, or just pick a fuse in the fuse box that isn't being used, you will NEVER have this problem. granted, heated O2s cost a few more bucks, but it is pennies compared to the hassle it saves you down the road.

I have gone back and forth and used heated and non-heated in my swaps and friends swaps, the heated O2 cars always performed better and got better gas mileage, and that's the bottom line.

some say they have had success with the Denso brand of non-heated O2s, but theres so many exhaust variables to consider whether they would work in your car or not. a nice free-flowing exhaust is significantly cooler than a stifled factory exhaust system with a factory catalytic converter, and O2s like to be mega-hot... its much better to just run heated O2s and forget it

Does the Fiero Factory still remove the SES light or just not even wire it in the harness? Epic fail. The mounts they make had poor welds on my install and weren't tightened well as I broke a boss. Also, they never adjusted my RPM gauge for a V8. When I told them, they never even shipped me a corrected one.

Knowing what I know now, I would never do a 4.9 swap if I had a v6 Fiero.

I spent roughly $4000 rebuilding a 3400 to use iron heads (with 3.4TDC pistons), porting and polishing the v6 heads, getting Trueleo headers, 19# injectors, porting the V6 intake ... Made 187rwhp/249 ft*lbs on a Mustang dyno. Might have spent another $1300 removing the old engine and re-installing the new...but still....

I spent ~$7500 on a Fiero Factory swap (not including shipping the car back and forth), later added Allante intake and Bosch design3 injectors as well as a custom tune and made 170/265 on the same Mustang dyno.

Actually, now that I'm DAWG modding the Fiero intake, I expect to make even more power on the V6...

Add to the fact that every 4.9 you buy is USED and they still charge you 2400 for it when I get them locally (any engine) for $500 ... not a good investment if you ask me.
I'm actually on my 3rd 4.9 engine and have had both cars from roughly the same amount of time ... add to the fact that I beat the crap out of my V6 (see me racing at Seekonk Speedway on youtube) and it still purrs...(both cars running since 2007).

If you have a 4cyl, then yeah, it's a nice upgrade from there.

[This message has been edited by lou_dias (edited 11-28-2013).]

yeah, I agree with Lou if you want a manual shift car that makes better use of the manual tranny gearing, the v6 is a better option for sure.. i like the grunt and feel of the 4.9L v8 better, BUT, the performance overall would be better with a 3.4 buildout for sure, and it will be easier to turbo in the future if you want to.

Lou, tell us about the wiring mods and computer mods that were made to accomodate the 3400 buildout, i'd love to hear how easy/difficult it was or wasn't

quote Originally posted by lou_dias: Does the Fiero Factory still remove the SES light or just not even wire it in the harness? Epic fail. The mounts they make had poor welds on my install and weren't tightened well as I broke a boss. Also, they never adjusted my RPM gauge for a V8. When I told them, they never even shipped me a corrected one. Knowing what I know now, I would never do a 4.9 swap if I had a v6 Fiero. I spent roughly $4000 rebuilding a 3400 to use iron heads (with 3.4TDC pistons), porting and polishing the v6 heads, getting Trueleo headers, 19# injectors, porting the V6 intake ... Made 187rwhp/249 ft*lbs on a Mustang dyno. Might have spent another $1300 removing the old engine and re-installing the new...but still.... I spent ~$7500 on a Fiero Factory swap (not including shipping the car back and forth), later added Allante intake and Bosch design3 injectors as well as a custom tune and made 170/265 on the same Mustang dyno. Actually, now that I'm DAWG modding the Fiero intake, I expect to make even more power on the V6... Add to the fact that every 4.9 you buy is USED and they still charge you 2400 for it when I get them locally (any engine) for $500 ... not a good investment if you ask me. I'm actually on my 3rd 4.9 engine and have had both cars from roughly the same amount of time ... add to the fact that I beat the crap out of my V6 (see me racing at Seekonk Speedway on youtube) and it still purrs...(both cars running since 2007). If you have a 4cyl, then yeah, it's a nice upgrade from there.

Yeah Lou, i agree that price is a little steep to me as well. In the past, I've charged people $6500 tops for a full turnkey manual swap that i did(converted an auto car), and all they had to supply was the fiero, i sourced all the parts locally. the engines were used, but usually low mileage engines pulled from a recently wrecked caddy that came with a warranty.

Lou has a good point. the 3400 V6 swap might be a more viable option for you, or heck, if you are feeling real kinky, the 3800SC is always a great swap, especially if you are willing to dump $7500 on an engine swap..

for me, i love the V8 sound, it just makes the ride everything i want it to be, and the 4.9L is still the most affordable way to get that sound IMO...but, if you want a performer, its not the best choice

quote Originally posted by lou_dias: I spent ~$7500 on a Fiero Factory swap (not including shipping the car back and forth), later added Allante intake and Bosch design3 injectors as well as a custom tune and made 170/265 on the same Mustang dyno.

quote Originally posted by stickpony: Hey Raydar, question that is slightly off-topic, but not entirely: when you had a fiero factory swap done, what chip did they use on yours, a modded one, or did they just use a VATS bypass with the stock module?

As far as I can tell, my chip was stock. There was a VATS bypass module installed. There was also a small R-C network installed, for the speedo.
(It's not stock any more, since I'm running the Allante intake and a Getrag, however.)

Keep in mind that mine was done around 2006. The swaps appear to have evolved (devolved? changed?) over the years. The welding on all of my brackets was first rate. I have often made the statement that you could pick up the car by the engine and shake it until the car fell apart, and the engine would still be firmly attached to the cradle. I know that the tech who was doing all the swaps (including mine) had some serious health issues, and left the shop. That was several years ago - before Jeremy even bought the shop. I don't know who is doing the swaps now.
I think that Lori may have been programming the chips for a while. I know she was selling them on eBay. But, last I heard, she isn't there any more, either.

Since I don't have the 4T60E to talk to any more, the Caddy ECM is getting ditched for a 7730 this winter. All I need to do is work up the enthusiasm to do it. I already have all the software and hardware. (I also need an A/C compressor. That's what I really need to work up the enthusiasm to swap.)

quote Originally posted by Raydar: As far as I can tell, my chip was stock. There was a VATS bypass module installed. There was also a small R-C network installed, for the speedo. (It's not stock any more, since I'm running the Allante intake and a Getrag, however.) Keep in mind that mine was done around 2006. The swaps appear to have evolved (devolved? changed?) over the years. The welding on all of my brackets was first rate. I have often made the statement that you could pick up the car by the engine and shake it until the car fell apart, and the engine would still be firmly attached to the cradle. I know that the tech who was doing all the swaps (including mine) had some serious health issues, and left the shop. That was several years ago - before Jeremy even bought the shop. I don't know who is doing the swaps now. I think that Lori may have been programming the chips for a while. I know she was selling them on eBay. But, last I heard, she isn't there any more, either. Since I don't have the 4T60E to talk to any more, the Caddy ECM is getting ditched for a 7730 this winter. All I need to do is work up the enthusiasm to do it. I already have all the software and hardware. (I also need an A/C compressor. That's what I really need to work up the enthusiasm to swap.)

cool cool.. you'll need a knock sensor too me thinks, at least most of the cars that work with a 7730 use one sounds like fun, and it will be much more easily tunable fo shizzle.

Actually, I took a 3400 and rebuiit it with 3.4DOHC pistons to get the compression back up and stuck Fiero iron heads and intake on it. So it's a 3.4 with a roller cam block like what Fierosound did. You can find all the details on my thread "Project 3400 roller cam block". No ECM change was necessary since I'm using all Fiero hardware.
The advantage of using a 3400 is the roller cam and the starter holes are on the correct side unlike a Camaro 3.4. The stock roller cam is superior to most Fiero street cams.
I had the machine shop drop the long block off and my entire swap was done by a regular mechanic in weeks rather than the months I see for full transplants from other members here.

I used the 3.4 DOHC pistons to get the compression up to 9.9:1 ... If I was planning on a future turbo I would have stuck with the regular Camaro pistons at around 9:1 ... The stock 3400 pistons would have netted about a 7.3:1 ratio on iron heads.

I don't recommend a full 3400 swap as that's a lot more work as you can see from the various 3400/3500 build threads. For the horsepower they gained, those people should have just went the 3800SC route and saved time, money and ended up with more power.

[This message has been edited by lou_dias (edited 11-29-2013).]

quote Originally posted by lou_dias: I have my knock sensor disabled on my 7730 swap that I eventually did to my V6.

I suspect that I will be doing the same thing, at least at first.

quote Originally posted by lou_dias: Actually, I took a 3400 and rebuiit it with 3.4DOHC pistons to get the compression back up and stuck Fiero iron heads and intake on it. So it's a 3.4 with a roller cam block like what Fierosound did. You can find all the details on my thread "Project 3400 roller cam block". No ECM change was necessary since I'm using all Fiero hardware. The advantage of using a 3400 is the roller cam and the starter holes are on the correct side unlike a Camaro 3.4. The stock roller cam is superior to most Fiero street cams. I had the machine shop drop the long block off and my entire swap was done by a regular mechanic in weeks rather than the months I see for full transplants from other members here. I used the 3.4 DOHC pistons to get the compression up to 9.9:1 ... If I was planning on a future turbo I would have stuck with the regular Camaro pistons at around 9:1 ... The stock 3400 pistons would have netted about a 7.3:1 ratio on iron heads. I don't recommend a full 3400 swap as that's a lot more work as you can see from the various 3400/3500 build threads. For the horsepower they gained, those people should have just went the 3800SC route and saved time, money and ended up with more power.

thats cool, l like that, much easier to maintain the stock look too.. you do the re-tune on the ecm yourself or just get someone like darth to do it?

quote Originally posted by stickpony: thats cool, l like that, much easier to maintain the stock look too.. you do the re-tune on the ecm yourself or just get someone like darth to do it?

Darth did one tune on the stock ECM where I made that power but was rich on the top end so there was still more power to be made, but then I saw my peak was at 4150 rpm (but damn 187rwhp) and I switched to the Trueleo+7730+DIS which actually lowered my HP by 10-15 because it provided too much air flow for a stock-ish cam and slowed down my air velocity.

So now I sent my old intake to be DAWG-modded and just got it back and I'll be putting that back on and hopefully get my power back and then some.