I've bit the bullet and am installing a LX9 3500 into my 86 GT. The local yard had a motor with 19k miles for $300 - I couldn't beat that price for a 3400. I've got the motor in my garage, have some last minute questions. Hopefully I can consolidate my questions into this thread.
I will be using the 7730 computer and the Fiero timing cover and accessories. This will allow me to keep my alternator and a/c pump, prevent me from custom fabricating a/c lines, keep my coolant plumbing on that side of the engine, and prevent notching the decklid. Also, going this route means I can't use the 24x crank sensor for OBD2 - but to me it's worth it. My goal is to make this swap successful, and document it step by step and make it an easy swap for others to use at minimal cost and fabrication.
I'll be using this crank trigger kit, which Marc from British Car Conversions says will work with the Fiero. RWD Crank Trigger Alternatively, I believe the 2.8L DIS setup would accomplish the same thing like found here. AFAIK the external trigger wheel meant for FWD pulleys will not work with the Fiero accessory drive system.
A thread which contributed a lot of information to my decision is found here. Thanks to Bob (cerulean) for the link.
A discussion on a LX9 short block and iron Fiero heads can be found here and contributed to my decision to use the entire motor.
Questions for now: 1 - I plan on running a 3100 fuel rail and regulator at 55 psi (stock) - Should I use 3400-style fuel injectors, or keep my 3500 injectors? 2 - Will a stock clutch be strong enough, or what would you recommend for a clutch? For a 5-speed Getrag transmission.
Thanks everyone! Pictures and progress to come.
[This message has been edited by masospaghetti (edited 02-23-2013).]
Keep the 3500 injectors, there is too much variety in the size of the injectors to ensure you are getting the right ones, or step up to 3800sc injectors right away.
Personally if your going with an OBD1, I would actauly use the 7165 ecu and run OSE12P there is a thread here about it. It would reqiure the least wiring stock fiero plugs can be used. There are base maps to use for V6 engines and tuning is very easy on it.
[This message has been edited by FieroWannaBe (edited 02-22-2013).]
Keep the 3500 injectors, there is too much variety in the size of the injectors to ensure you are getting the right ones, or step up to 3800sc injectors right away.
Personally if your going with an OBD1, I would actauly use the 7165 ecu and run OSE12P there is a thread here about it. It would reqiure the least wiring stock fiero plugs can be used. There are base maps to use for V6 engines and tuning is very easy on it.
The stockclutch will not hold up. Ive had trouble with parts store clutches on a stock 2.8l. I would run a clutchnet unit, I have read good things. I have a spec stage 2 on my 3.4 DOHC (about the smae power as a LX9).
Keep the 3500 injectors, there is too much variety in the size of the injectors to ensure you are getting the right ones, or step up to 3800sc injectors right away.
So the injectors are electrically compatible? Aren't some injectors high impedance and some low impedance?
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Personally if your going with an OBD1, I would actauly use the 7165 ecu and run OSE12P there is a thread here about it. It would reqiure the least wiring stock fiero plugs can be used. There are base maps to use for V6 engines and tuning is very easy on it.
I would like to keep EGR though and the 7165 does not natively support EGR. Chetw77cruiser says this could be gained back through the programming "somewhat". The ease of this swap is certainly appealing though.
[This message has been edited by masospaghetti (edited 02-22-2013).]
I would like to keep EGR though and the 7165 does not natively support EGR. Chetw77cruiser says this could be gained back through the programming "somewhat". The ease of this swap is certainly appealing though.
I believe people have been able to make EGR work with OSE12P, you would hav eto check delcohacking.net to be sure. But the option to program it is there. [ http://delcohacking.net/for...topic.php?f=27&t=356 ] The injectors should work fine, In GM's, low impedence injectors are usually TBI units, most port injecectors interchange well enough.
I applaud you for using the aluminum heads, the injectors will work fine, Please take lots of pictures along the way, and don't hesitate to PM me with any questions. there are a couple of 3400 and 3500 swapped Fieros on 60degreeV6.com, Me, Caffeine, hookdonspeed, Kaiju Senso. and Mars are the first ones to come to mind. I started a "Fiero owners group" over there, so if you join the site, be sure to PM me(same username) and I'll get you in.
Keep us posted on the progress of the swap! ------------------ we're in desperate need of a little more religion to nurse your god-like point of view...
The stockclutch will not hold up. Ive had trouble with parts store clutches on a stock 2.8l. I would run a clutchnet unit, I have read good things. I have a spec stage 2 on my 3.4 DOHC (about the smae power as a LX9).
Maybe it's a freak clutch, but I put in a slightly used 4-speed stock clutch (2.8) when I swapped my 3500 and 30,000 kms later it hasn't slipped yet. I've done plenty of drag racing and some autoX with the car as well and have also used a 75hp shot of N2O a few times. I don't know what brand the clutch is but it was installed by Canadian Tire about 2000 kms before I bought the car and I figured I'd give it a shot. I'm glad I did. However to the OP, if you don't plan on keeping the engine stock, now is the best time to install an upgraded one.
if you are using your stock fiero front engine mount, make sure you tell that to Marc, the holder for the crank sensor uses the same bolt holes in the block, and may mis-align the sensor to the wheel. I ran into this problem with my FWD external crank trigger.
the 3100 FPR should be 45 PSI not 55.
------------------ we're in desperate need of a little more religion to nurse your god-like point of view...
Not 100% apples to apples but for my GT 4 speed Muncie, a stock, Federated Auto Parts, clutch holds up to my 3400 no problem, before and after the WOT Tech "Strip" camshaft was installed.
If you do go the route of 3400 injectors for whatever reason, you might as well grab the 3400 fuel pressure regulator as well. My 3400 was running on stock, 3100 fuel injectors and FPR (to match the 3100 computer I was using, to avoid any possible issues tuning). I have since upgraded to the 28# Trailblazer injectors (which involved a connector swap). I can't prove if my stock LNJ 3400 injectors could have been used though.
With the external 7x crank trigger, I didn't notice any misalignment issues?
Not 100% apples to apples but for my GT 4 speed Muncie, a stock, Federated Auto Parts, clutch holds up to my 3400 no problem, before and after the WOT Tech "Strip" camshaft was installed.
If you do go the route of 3400 injectors for whatever reason, you might as well grab the 3400 fuel pressure regulator as well. My 3400 was running on stock, 3100 fuel injectors and FPR (to match the 3100 computer I was using, to avoid any possible issues tuning). I have since upgraded to the 28# Trailblazer injectors (which involved a connector swap). I can't prove if my stock LNJ 3400 injectors could have been used though.
With the external 7x crank trigger, I didn't notice any misalignment issues?
The front motor mount spaced my sensor mount away from the wheel, so it no longer lined up with the wheel, Marc sent me a mount designed to work with the front engine mount to replace it.
He has a 3500 in his car and it is working well. He may be able to answer most of your questions with real world results to back them up. we did a 7730, I think he used $a1 code.
I didn't have any issues with the FWD trigger but mine is the adjustable style and the new ones are non-adjustable. The OP already indicated he was buying the new RWD trigger to work with the Fiero timing cover, since the FWD trigger won't be a bolt-on.
You can't use the stock LX9 injectors with a 3100 or 3400 fuel rail, however you can use an AFPR or vette fuel filter with the 3500 rail. If you are able to pick up a return-style rail with suitable injectors though, that's probably the best option. Ive always had a rich idle with the vette fuel filter setup. Others have had issues with tuning the stock injectors as well, but it CAN be done .
If I was to do the swap again, I would keep the FWD timing cover for the nice serpentine belt setup but low mount the alternator and use the stock dog-bone setup. I recommend poly transmission mounts as well, though stock should suffice for a while. I recently broke one of the stamped steel trans mount brackets into three pieces the other day, so if you can weld it might be a good idea to reinforce the mounts.
One more thing comes to mind: use locktite on the trigger wheel/mount bolts. I had mine work loose a few months ago and it caused all kinds of strange ignition problems until I heard the sensor rubbing on the wheel and figured out the problem!
My point is that the RWD mount is probably designed to bolt directly to the block, as most RWD applications don't use a mount that bolts to the front of the engine. if you put the front motor mount on, it will move the sensor further away from the block, and messing with the alignment.
Edit to add pics of what I'm talking about
[This message has been edited by ericjon262 (edited 02-23-2013).]
I would like to keep EGR though and the 7165 does not natively support EGR. Chetw77cruiser says this could be gained back through the programming "somewhat". The ease of this swap is certainly appealing though.
If you live in an area where emissions testing is needed, then you will need the egr to function. With this engine and a good tune, I wounder if the egr will even be needed. Since your car is older than 1996, I believe that emissions testing is not needed, unless the county requires it. Safety inspections are, and don't tint your windows darker than 35%. Either way, the mounting flange for the linear egr on your engine is nearly identical to the stock egr valve. The mounting bolt holes may be at a different spacing, but without either on hand to take some measurements, I am not for certain. We can get egr going, but the function will be fairly similar to how the earlier duke engines worked. Basically rpm and vacuum dependent, but at least those are adjustable using the 7165.
My point is that the RWD mount is probably designed to bolt directly to the block, as most RWD applications don't use a mount that bolts to the front of the engine. if you put the front motor mount on, it will move the sensor further away from the block, and messing with the alignment.
Edit to add pics of what I'm talking about
From your pictures, that could be an issue. Time for a cut and weld. Or a thicker washer between the trigger wheel and harmonic.
Ericjon262: Isn't that the FWD style crank trigger? The RWD style has notches cut into the balancer. Nevertheless, I agree it would be a good idea to tell Marc, and i"ve sent him an email.
Are any of the 3100/3400 fuel regulators 55 psi, or are they all 45?
bcampbell: You can't use the stock LX9 injectors with a 3100 or 3400 fuel rail, however you can use an AFPR or vette fuel filter with the 3500 rail. If you are able to pick up a return-style rail with suitable injectors though, that's probably the best option.
What would be suitable injectors with the stock 3100/3400 rail?
chetw77cruiser: I wanted to keep EGR mostly for fuel economy benefit, if possible. The car is old enough it no longer needs emissions inspections.
Thanks everyone for the replies! I really appreciate the help.
What would be suitable injectors with the stock 3100/3400 rail?
Having never delved into the 3500 swap before, I can't say for certain, but it sure looks like the 3500 injectors are quite a bit shorter, to clear the upper intake plenum- has somebody fit the older style 3100/3400 injectors and rails into a 3500 intake setup before?
Having never delved into the 3500 swap before, I can't say for certain, but it sure looks like the 3500 injectors are quite a bit shorter, to clear the upper intake plenum- has somebody fit the older style 3100/3400 injectors and rails into a 3500 intake setup before?
My crank trigger is a FWD unit. also, My 65# injectors fit under the plenum fine, and they were longer than the 3500 injectors.
The FWD trigger won't bolt to the Fiero balancer. I believe the RWD trigger kit will work with the Fiero because the notches are cut into the balancer, which is fairly thick; I imagine a 1/4" piece of steel won't place the sensor too far out. But I agree with the others, check with the guy who sells them before buying. Do NOT buy the FWD trigger unless you are prepared to modify it or use the FWD timing cover/balancer.
Also here is the crank trigger I'm using, it is the old adjustable style from TCE. This is the old FWD style, not intended for the Fiero timing cover swap. There really isn't any misalignment issues. (sorry the pic isn't that great, but it's all I have right now)
For the coil pack bracket on both my 3500s I drilled and tapped 6 holes in the 3500 ICM bracket and it works fine. Edit: you have to drill a couple other holes as well to clear some protrusions on the 3400 ICM.
[This message has been edited by bcampbell (edited 02-23-2013).]
Since there's an issue with the crank trigger wheel in that area, be sure to get the balancer retaining bolt torque correct, the crank timing gear is a loose fit and the high torque on the bolt is intended to make sure it doesn't slip (shear the key) and ruin the valves.
Post PRE 2000 ("small port" 3100), but the physical rail doesn't matter. Use whichever one you want, the injectors and regulators should be interchangeable for the most part. You will need to do some trickery to get the regulator to clear the 3500 upper intake plenum though. (I forget if this was mentioned anywhere)
Trailblazer 28# injectors and 3.4DOHC 24# injectors seem to be popular choices when using a 3400 rail. Higher the fuel pressure the more power they should support; as a general rule anyway. Depending on the injectors you go with the 43.5 psi regulator might be fine.
Out of curiosity, what would be the gain of using the stock 3500 returnless fuel rail when not running OBD2? Isn't the tune going to be custom enough that any benefits of the returnless system are negated? If this is the case, whats wrong with going the easy route of a bolt on return style fuel rail?
Out of curiosity, what would be the gain of using the stock 3500 returnless fuel rail when not running OBD2? Isn't the tune going to be custom enough that any benefits of the returnless system are negated? If this is the case, whats wrong with going the easy route of a bolt on return style fuel rail?
It's just convenience. You can use the stock rail and later model injectors that came with the motor, or go retro and use the earlier injectors.
Sorry, I had a typo in an earlier post (which i edited and scratched out the wrong word). I was using 94-99 complete fuel rail.
94-99 3100 injectors are different from 2000-2004 3400 injectors (different wire connectors and dimensions are most obvious). I do not know if 2000+ injectors were shared on 3100 and 3400 engines.
In my opinion any of the gen 3 660 injectors will work because you'll need to do some tuning with the OBDI computer anyway. I can not comment on if any set of injectors have a better spray pattern.
I have a 3100 rail I can send you (just pay shipping) minus the injectors. I would get injectors slightly larger than necessary to make room for future upgrades.
If staying with 3x00 injectors I would grab a 3400 set and use them with the 55psi regulator simply to have the ability to supply more fuel. 3100 injectors with a 43.5 psi regulator may be close to maxed out on a 3500. Maybe even maxed out.
Not sure, but I think the 3100 injectors are 19lbs. At least the ones I bought( 00+ Malibu ) were. The DOHC 3400 injectors have a different spray pattern designed specifically for the DOHC valve design. Joseph Upson brought this to light on page 2 of my build thread( 3500(LX9) into a Fiero ) on the 60degreeV6 website. http://60degreev6.com/forum...p-into-a-Fiero/page2
I'm pretty sure the 3100/3400 injectors are not going to be compatible.
[This message has been edited by flimbob (edited 02-24-2013).]
Not sure, but I think the 3100 injectors are 19lbs. At least the ones I bought( 00+ Malibu ) were. The DOHC 3400 injectors have a different spray pattern designed specifically for the DOHC valve design. Joseph Upton brought this to light on page 2 of my build thread( 3500(LX9) into a Fiero ) on the 60degreeV6 website. http://60degreev6.com/forum...p-into-a-Fiero/page2
I'm pretty sure the 3100/3400 injectors are not going to be compatible.
Not compatible with what? As long as they're used with the 3100 or 3400 rail, they're fine. As stated earlier, the 3500 rail requires an external regulator anyway. 3100/3400 injectors are too long for the 3500 rail. Plenty of swappers have used the 3100/3400 rail with a 3500.
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