OK. Even though I don't plan on swapping until next winter, at the soonest, I want to get everything sorted so I can start pricing...

I have settled on doing a supercharged 2.4L TwinCam swap with the stock 4-speed auto. I am going to list everything I think I need, and those more experienced please add so I have everything I will need.

- 99+ LD9 2.4L TwinCam engine (99+ removed EGR and added high impedance injectors)
- 4-Speed Auto
- GM LD9 Supercharger
- 99+ LD9 ECM
- 99+ Wiring harness
- Fabricate mounts
- "Secret" cam swap (95 Quad4 intake cam, 94 Quad4 exhaust cam)

Please lend a hand so I know what I am going to need.

Hmmm....I can understand those who swap in a Quad4 HO, @ 180 HP, without a supercharger, but why an LD9? Doesn't have much in the way of parts, not a currently supported engine, etc. GM IS supporting the Ecotec with HP parts, 2.2L engines with low miles are now under $500 in a lot of wrecking yards, and SS Cobalt engines are now starting to become available in the yards ( still expensive, but a LOT less expensive than the supercharger you need to buy from GM for the LD9 )
Now, as to the swap, there was a getrag available for HO Quad 4's 89 - 94. Rare, but I found one last year. Will work with stock Fiero getrag cables and mounts. Has the right bellhousing pattern for the LD9. Even if you find one, it'll be at least 15 years old, and rpobably needing a rebuild. ( people tended to trash them back then )

For the Ecotec, Bates engineering makes an adaptor to adapt Ecotecs to the M6 ( GM FWD ) bellhousing pattern. You can use any FWD trans including the Isuzu 5 speed ( available as NOS on Ebay ) because that tranny is rated at 200 ft-lbs max. I wouldn't attach it to a v-6, though. Solves the problem of axles, VSS, shift cables and so on. Use the 2003 cavalier or saturn ion computer, or megasquirt it or roll your own for fuel/ignition. You get the latest design 4 cylinder, massive hop up parts availablity, light weight, etc. Plus, if you use the Fiero MT3 ( Isuzu 5 speed or is that MT2 ?- I forgot ) you can expect 35+ mpg freeway NA. what more could you ask for? Maybe later you could swap in the Saab or F40 six speed, insturments, etc. None of which are avalable for the LD9. What do you think?

So you think I should use a 2.2L Ecotec instead of the twincam? Do they make a supercharger for it? And didn't GM build up an Ecotec to around 1000HP at one point?

SS Cobalts are supercharged.

Do some research, mechanically, the swap you are contemplating is fairly easy. ( either Ld9 or Ecotec ) But Electriclly, difficult. How are you going to defeat the VATS? What about the VSS? How about the instruments?

Swapping the entire wire harness is not easy, and may not solve the problem with the ignition. Will you need to change the column?

At any rate, I wish you luck. If you have specific questions, this is a great place to have them answered.

For your information, try www.car-part.com. As with any wreckers, be careful and ask exactly what is included. Some will lowball to get you in the door, their price may not include anything but the block and heads.
Bates is at www.batesengineering.info They call the Ectoec the L850 under drivetrain parts the adapter for Ecotec to M6. I think it was $225 last time I asked.

That was one of the reasons I wanted to use the LD9. It is capable of being run by a Quad4 ECM, which is OBD1. That would eliminate the issue of gauges and ignition and such.

Ahhh...in the original post it was the 99+ ecm, but please check the position of the sync notch on the reluctor wheel on the LD9. On the LGO ( the 2.3 Vin A 180 & 190 HP version ) it had a 7 notch reluctor wheel on the crankshaft with 6 evenly spaced notches and the sync or seventh notch at 15 deg BTDC. On the LD9, I have heard that it was different, but I don't know what the difference is.

BTW, you can run any 4 cyl engine with any 4 cyl ecm, if you use the sensors, timing, injectors, throttle body, that match the ECM etc and the engines are close to the same size.

The ecotec also uses a 7 notch reluctor wheel on the crank, but the sync notch is 55 deg ATDC, so if you want to use the early quad 4 ecm, you need an externally mounted crank sensor and custom reluctor wheel with notches in the right places. Plus, I think camshaft timing has to be similar to the early quad 4's, in order for the fuel tables to work right.

W41 eproms are still available ( at least they are still listed at rockauto.com from acdelco ) I believe the code for the prom is AXRM for a 1991 Cutlass Calais International. Unfortunately, this ECM came only on 5 speed cars. All the automatics were of the low performance variety. Actually, I am thinking of doing this myself ( Ecotec swap using the early quad 4 ECM.) I have a couple of the right ECMs and various other parts, and I think that they will work with an Ecotec if I get the right camshafts and use quad 4 sensors and quad 4 DIS ignition module. You are right that this ecm will work with Fiero instruments. Uses 4000 PPM same as Fiero for the VSS so that solves the speedo / cruise control issue.
89 - 91 Quad 4 ECM = 1228707
Quad 4 Vin A = 2265 cc
Ecotec L61 = 2189 cc

A lot of people will tell you that OBD I ECM's dont have adjustability, and that is true, so if you are goiing to use the supercharger, it probably won't work with the Quad 4 ECM, as it came on a NA engine. Only the later OBD II ecms can be used with the supercharger.

The real reason I brought up the Ecotec is reliabilty. The early Quad 4's had a very high percentage of head gasket failures and cracked heads. It's why that eingine was redesigned several times, ending in the LD9 - which still experienced head gasket failures at a higher than acceptable rate, which is why it was finally replaced completly by the Ecotec. I believe there are several people on this forum who have Quad 4 equipped Fieros, but most were done years ago, I haven't heard of recent swap. Correct me if I'm wrong, Quad 4 swappers! On top of that, check out parts prices for LD9's and Quad 4's. Through the roof! you could buy TWO low milage ecotecs for what it costs to rebuild the Quad 4 based motor. ( either LD9 or Quad 4 )

I agree that it would be easier mechanically, most Quad 4's were swapped into Fieros without a kit.

quote Originally posted by niemann99: Hmmm....I can understand those who swap in a Quad4 HO, @ 180 HP, without a supercharger, but why an LD9? Doesn't have much in the way of parts, not a currently supported engine, etc. GM IS supporting the Ecotec with HP parts, 2.2L engines with low miles are now under $500 in a lot of wrecking yards, and SS Cobalt engines are now starting to become available in the yards ( still expensive, but a LOT less expensive than the supercharger you need to buy from GM for the LD9 ) Now, as to the swap, there was a getrag available for HO Quad 4's 89 - 94. Rare, but I found one last year. Will work with stock Fiero getrag cables and mounts. Has the right bellhousing pattern for the LD9. Even if you find one, it'll be at least 15 years old, and rpobably needing a rebuild. ( people tended to trash them back then )

The LD9 is a great motor to swap instead of the Quad-4. The TwinCam IS a Quad-4. The 2.4 TwinCam has balancing shafts to make it run smoother. With the "Secret Cam Swa" (silly name), it puts out 165hp. WIth the SuperCharger available from GM, you're looking at about the same power as a Cobalt SS.

The REAL benefit, however... to the TwinCam, is that it can actually be completely CONTROLLED by a Quad-4 OBD1 computer. Doing it this way allows you to retain the stock Fiero gauges (if that was the goal). Going with a much newer motor like the EcoTec, would require you to try to adapt the OBD-2 system in your car. This almost always ends with having to purchase a set of aftermarket OBD-2 compatible gauges, or using gauges from an OBD-2 vehicle.

The ENTIRE swap for the TwinCam can be done VERY cheaply. The most difficult part about it, is getting the GM Performance Parts supercharger for the TwinCam.


Both motors, the Ecotec and the TwinCam will give the end user excellent power, with superior fuel economy. A 2.4 TwinCam in a Fiero with the 4-Speed manual will yield around 32-35mph on the highway @65mph.

The Ecotec swap will be much more involved (simply for the entire wiring aspect of it).

Don't be discouraged, the TwinCam is an excellent motor to use.


www.Mantapart.com has anything you could ever possibly want to buy for the 2.4. Anything you can get for the Ecotec, they have for the 2.4 TwinCam.

I would be 100% gung-ho for the Ecotec, but I fully support a 2.4 TwinCam swap for no other reason than the parts are more currently plentiful (at cheaper prices) and that you can make 100% use of the OBD-1 Quad-4 computers. (Go with a 1993-1995 computer).

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 (3.2) 5-Speed
1984 Porsche 944 5-Speed
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

Thanks for reminding me!

That the amount of time effort and $$ put into any engine swap / body mods etc makes every mod very personal. Each has to find their own way and flavor, and information and opinions are always helpful.

I drove a Fiat 124 in the 70's which was not known as a trouble free car, in fact, everyone I ever knew who had one had troubles, especially electrical gremlins, and one guy I knew went through seven exhaust header gaskets in three years. I never had a single problem, but I wouldn't bet $1000
( or however much the swap costs ) that you won't have troubles with the LD9. Sure it's a version of the Quad 4 - but I already said that didn't I?

Everyone has their own priorities, and mine are: does it make sense, end result, and ease of swap. To me, putting in a motor that has known troubles is asking for trouble and doesn't make sense. We want to drive our cars, not work on them all the time. Oops! Did I really say that? What am I thinking?


That said, the LD9 is an OK motor, and yes, there are people who will reprogram the eprom. I've never had much luck with that, and I wouldn't trust the programming on a supercharged motor because once the eprom is in there, that's it, you can't adjust it on the run, as you can with the OBD II ecms.

quote Originally posted by niemann99: That said, the LD9 is an OK motor, and yes, there are people who will reprogram the eprom. I've never had much luck with that, and I wouldn't trust the programming on a supercharged motor because once the eprom is in there, that's it, you can't adjust it on the run, as you can with the OBD II ecms.

You certainly know your stuff, so I won't disagree with you. However, I am a big fan of the TwinCam. It has all the good stuff of the Quad-4, with many improvements. Most of the flaws that were inherent in the TwinCam can be eliminated or drastically reduced with a better and higher quality head gasket. True, I didn't have any problems with my TwinCam, but the TwinCam had vastly fewer problems than the Quad-4 did. They used the Twin Cam in Cavaliers and Sunfires for many many years.

That said, there are far better swaps (power for dollar) than any of these. The 4.9 will immediately put you in the mid 14s with an otherwise totally stock block and heads. It also weighs less than the stock V6 or the stock L4.

But, I think really, either engine is a great swap.

However, if you WANT to keep your factory gauges, as far as I know, the Quad-4 and TwinCam is really the best way to go. I only suggest the TwinCam cause it's more refined than the Quad-4.

If there really is a way to make the Ecotec run with the Quad-4 ECM, that would be very cool.

I have a VVT 2.4 Ecotec in my Solstice, and it's a great motor.

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 (3.2) 5-Speed
1984 Porsche 944 5-Speed
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

Thanks for all the info here guys. There's really some food-for-thought here.

I have a few reasons for choosing the Twincam over more powerful solutions. Mainly I want something that hasn't done hundreds of times before. If I cared too much about power or ease I would use a 3800 S/C.

But it is good to know people on here who can give me an idea of what issues I will hit when the swap starts.

But it definitely looks like I need to do a lot of research before I attempt this.

I've got a supercharged LD9 in my Cavalier. I keep saying that if the Cav ever gets rear-ended that the LD9 is going in the Fiero.

Some have suspected the head gasket was partially due to lower quality material. Also keep in mind that the compression ratios in the HO and W41 were quite high. 10.5 and 11:1. The LD9 is relatively low at 9.5 (LO Q4s were also 9.5:1 IIRC).

Other possible contributing factors to premature head gasket failure have been attributed to extended idling and Aluminum head mated to cast iron block.

The only other information I have is from experience. Mine has 98000 miles on it, and I have had the supercharger on it since the 65000 mile mark. Daggum thing just screams!

Honestly, if you are going to use the LD9 and have it out of the car, it might be worth looking into converting the LD9 (TwinCam)'s oiling system to the older Quad4 style, I think it was higher volume.

Oh, and I would avoid Mantapart, too many people had bad experiences with them over on www.j-body.org and www.quad4forums.com

Speaking of which, www.j-body.org and www.quad4forums.com are great resources (I'm squisher00z24 on both).

I have joined the Quad4 forums.

Have you ever dyno'd your cavy? I would like to know exactly what kind of HP you get from that motor and s/c.

But in the end, do you think it is worth the trouble to use this motor?

Never had the cavy on the dyno, but GM claims 190hp (I'm guessing at the crank)

Guys on www.j-body.org have achieved 220 or so with further tuning and a real exhaust setup (I'm running stock exhaust still)

I ran 15.1@90mph in the quarter at IRP in July of 2005. About 95 degrees in the shade, everybody was doing lousy, plus that was my first time drag racing ever.

Is it worth it?

Maybe, I like the motor myself, but I understand that it can be a challenging swap. If you already had the motor and blower setup, I would go right ahead and do it.

If you're set on doing it like this, check the classifieds at Quad4forums and j-body.org, sometimes people are selling used blower kits there. Be careful, as GM has also released a blower kit for the 2.2 Ecotec. In the long run, the ecotec may be a better option, but the TwinCam is still a decent motor.

The ecotec brings into question the OBD2 issues. While the Ecotec is deffinately a better motor, the required swapping of gauges is what is turning me off.

I think I may have to rethink the twincam, being so many people are against the idea. But depending on what I can find and at what price, it way still be a viable swap.

Ok, folks. I have the opportunity to get a full 96 Grand Am with the Twincam for $125 plus towing from PA to NY. This will get my the motor, tranny, wiring, and ECM. Do you think it is worth it to get this car?

How does it run? Mileage?

Also, the 96 will need a couple of modifications to run with the GM supercharger. ('00+ starter, and a couple of other things, there's a sticky for it on jbo)

However, if it runs well, and the trans is in decent shape, that's a pretty good buy. I wouldn't feel too bad about sinking some money into a forged bottom end for that guy and running a turbo on it instead of the supercharger.

It has 111K miles and needs a new head gasket. Thats all I know.

quote Originally posted by Shad0wguy: The ecotec brings into question the OBD2 issues. While the Ecotec is deffinately a better motor, the required swapping of gauges is what is turning me off. I think I may have to rethink the twincam, being so many people are against the idea. But depending on what I can find and at what price, it way still be a viable swap.

So many people are against the TwinCam, because they don't know anything about it. The TwinCam is a great motor. The TwinCam was teh RELIABLE Quad-4. There is nothing really inherently better about the "standard 2.2 liter" ecotec, from the 2.4 TwinCam.

OBD-2 is a real hassle to mess with. When someone offers an OBD-2 gage processor box, which allows you to adjust and hook up all your own factory gages to it, then I'd say go for it. But ALL that work and hassle you're going to go through, dropping a s**t underpowered 4 cyl into a Fiero, only to have to THEN worry about all the wiring... why bother?

The 2.4 TwinCam HAS been done before, and you'll get excellent fuel economy, excellent power, AND... it's OBD-1.

Don't get me wrong, I really like OBD-2... but not for swapping a new motor into an older car.

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 (3.2) 5-Speed
1984 Porsche 944 5-Speed
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

Yeah, that was the plan. The 95 Quad4 had a transitional motor so will be best to use with the Twincam. The only thing I am wondering is that I owned a 95 Grand am 2 years ago. It had a 3-speed auto. Were there other Quads that had the 4-speed so the ECM will be configured correctly?

OK, so it looks like I am going to stick with the TwinCam. But it is going to be a 99+ because of the upgrades it recieved for that year (EGR removed, better injectors) will support the S/C better.

So now that we have that out of the way, aside from motor mounts, do you see any other things that will require fabrication?

so whats wrong with these guages?cost me 65 dollars at the wreckers and a little bit of grinding and cutting and in they went.made my own plexiglass cover .somebody more talented than me could make it look better .i dont really care whether you like an ecotech or a Q4 ,but the eco is not that hard of a swap.and soon there is going to be a kit available

What is this about OBDII and gauge compatibility? What have you read that makes you think that's a problem?

Why does niemann99 think that OBDI computers can't be tuned?

quote Originally posted by Will: What is this about OBDII and gauge compatibility? What have you read that makes you think that's a problem? Why does niemann99 think that OBDI computers can't be tuned?

That gauge issue is due to the fact that any OBD2 motor runs the gauges digitally, whereas OBD1 or earlier gauges are operated mechanically. It would require that I swap out the gauges in order to use an OBD2 ECM.

quote Originally posted by wftb: the other thing everybody seems to forget is that you need an adapter plate to mate a Q4 to a fiero tranny.with the ecotec you just use the tranny from the cavalier and the fiero axles fit right in .and if you want to use a fiero tranny gm sells an adapter plate to do that.there are now 3 documented , running ecotec fieros .within a year there should be many more .why waste your time with a non production motor that will cost more than an ecotech.

I am not planning on using the stock Fiero tranny. I am going to use the 4-speed auto that comes with these motors.

[This message has been edited by Shad0wguy (edited 01-12-2007).]

quote Originally posted by Shad0wguy: I am not planning on using the stock Fiero tranny. I am going to use the 4-speed auto that comes with these motors.

What do you mean by "digitally"? They don't run the gauges off the databus for OBDII... that's MUCH later (like '05+) with the CAN bus. As OBDII came out, GM started to use computerized instrument panels, but they still take their input from the same sort of senders and sensors as the older gauges.

Besides, what's to stop you from installing the Fiero sensors on the engine and running the Fiero gauges? I don't get what you think the problem is.

Nice to see so many opinions. Those who do the work get to make the choices, all the rest of us can do is chime in and give atta boys.

Hmmm....Grand Am with the LD9 Twincam...maybe has a blown headgasket? That to me would be a big hint if it does.
OBDI can't be tuned? Don't think I said that, just that it's a PITA.
Ecotec? Can be done, but still not a well known option. Looking for a kit to come out soon....who's the most likely to make one?

Anyway, good luck. Anyone who's willing to go through the headaches and work of any swap to get what he wants out of the car....my hat's off to 'em.

quote Originally posted by wftb: so whats wrong with these guages?cost me 65 dollars at the wreckers and a little bit of grinding and cutting and in they went.made my own plexiglass cover .somebody more talented than me could make it look better .i dont really care whether you like an ecotech or a Q4 ,but the eco is not that hard of a swap.and soon there is going to be a kit available

There is nothing WRONG with your swap. It looks great, and I think it's very nice. But some people (like me), prefer gauges to look stock. I personally prefer the stock look, and that definitely doesn't look stock.

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 (3.2) 5-Speed
1984 Porsche 944 5-Speed
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

quote Originally posted by niemann99: Nice to see so many opinions. Those who do the work get to make the choices, all the rest of us can do is chime in and give atta boys. Hmmm....Grand Am with the LD9 Twincam...maybe has a blown headgasket? That to me would be a big hint if it does. OBDI can't be tuned? Don't think I said that, just that it's a PITA. Ecotec? Can be done, but still not a well known option. Looking for a kit to come out soon....who's the most likely to make one? Anyway, good luck. Anyone who's willing to go through the headaches and work of any swap to get what he wants out of the car....my hat's off to 'em.

OBDI is easier to tune than OBDII since the advent of EPROM emulators. OBDI boxes can be tuned on the fly without even having to shut off the engine. To tune an OBDII car you have to stop the car and shut off the engine to reflash.