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padgett

Very interesting

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I liked that he used OBD1 and probably just used the excisting harness. So the dash probably works fine. The only thing is how is he using a computer controlled trans? maybe it is a PCM from a 91? that way he can have everything work and still have the perameters for the "E" trans. I bet that thing hauls ass!

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Just about everything is on the L67Swap page (be patient, it often took a couple of tries to come up but worth it). I have sent some e-mails and we will see what happens. I do believe that the 94-95 PCM is the place to begin particularly for an engine with the linear EGR or needing more than 170 gm/sec MAF readings.

The thread is pretty much a step-by-step on what needs to be done mechanically to put an L-67 (supercharged 3800) into a 1989 Reatta. I knew this was possible just never had the time (or the need) to go through all of the steps) and is hard to work on a car that is usually 1500 miles away.

Have considered a couple of times just finding a car and doing it but my wife cannot afford for me to retire yet.

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I don't like this conversion because he axed the ECC. F dat. Supercharger series II or not, to me, the ECC makes a Reatta feel like a Reatta.

Like my dad's '90 drop top; it just doesn't feel right.

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A really good question that I'm not sure he could answer is: Could he integrate everything electronically to allow for proper function of the CRT? I wish the car owner had pushed for this...then we might have an answer. Does anyone here think this is possible for a reasonable $$ amount? I would love to do this swap as long as I can keep the CRT. Personally, I think this is a very neat and unique feature on these cars and everyone that gets in the car with me comments on it.

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I'm sure the series II would be a lot more difficult compared to Greg's series I.

Is it really true that the old supercharged 3800 had like 20 HP over the naturally aspirated one? Well Greg's got a sticker anyway

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I really think using the 94-95 L67 computer is a cleaner answer since all of the engine management and sensor values are already right and the "E" trans programming is already there

Turns out the gentleman kept the ECC at least initially but is missing tach and coolant temp displays (and I suspect the engine is getting the wrong speedo information) and the a/c is not working properly.

For Greg's we were able to use the 88 Computer so the data stream was right but there are still a few elements that are not right (we also learned a bit about spark advance curves and boost).

NONE of this is impossible, it is just a matter of reprogramming the PCM the match the Reatta ALDL communications, is how it "talks" to the BCM which controls the displays. Since the Reatta has built in MPG and scan tool capability, this is a whole lot more complicated than putting a 3800 in a Fiero, that is if you want everything to work.

This is part of the reason I am trying to build a simulator but is *very* time consuming - time which, as yet, I have not been able to find.

However it is possible and will happen just as soon as there is enough motivation, just not yet.

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<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> (we also learned a bit about spark advance curves and boost).

</div></div>

And an expensive lesson it was! (damaged Piston Pic attached)

After making the timing chart/ retard values changes I was stupid to not immediately start using that modified PROM. Ran for most of a year on the old '88 n/a timing charts and repeatedly saw Knock Counts pile up. Last Fall I started chasing a phantom miss, swapped plugs, wires, ignition Module, etc. Finally did a compression test and found #1 and #3 low. That Oil Change showed emulisfied oil so I took her off the road and ordered parts, assumed I just had a blown head gasket. Once the engine was out and heads off I had a badly carboned up #1, pulled that piston and found a broken ring/ broken ring ledge.

Sent the short block to a machine shop/ racing engine builder. Once torn down completely for clean-up and inspection the second broken piston was found. Block was fine so a set of pistons, rings, and top to bottom bearings were ordered. Light hone to promote ring seating and reassembly and I got her back on the road this week about $1500. poorer. The engine builder blamed the damage on Knock. Works good now though!

I had about 75 k miles on that engine so she now has a new lease on life.

And relating to this thread, I'm convinced having the benifit of full screen function and diagnostics intergrity is worth the effort. I also believe as compared to the original stock 150 hp I've gained at least 60 hp and have the potential to add that much again. In the meantime I drive the Reatta with manual 5-Speed and spunk I always wanted. smirk.gif

Have cake and eat it too! laugh.gif

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<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I really think using the 94-95 L67 computer is a cleaner answer since all of the engine management and sensor values are already right and the "E" trans programming is already there

Turns out the gentleman kept the ECC at least initially but is missing tach and coolant temp displays (and I suspect the engine is getting the wrong speedo information) and the a/c is not working properly.

For Greg's we were able to use the 88 Computer so the data stream was right but there are still a few elements that are not right (we also learned a bit about spark advance curves and boost).

NONE of this is impossible, it is just a matter of reprogramming the PCM the match the Reatta ALDL communications, is how it "talks" to the BCM which controls the displays. Since the Reatta has built in MPG and scan tool capability, this is a whole lot more complicated than putting a 3800 in a Fiero, that is if you want everything to work.

This is part of the reason I am trying to build a simulator but is *very* time consuming - time which, as yet, I have not been able to find.

However it is possible and will happen just as soon as there is enough motivation, just not yet. </div></div>

Hello, I am the person who did the L67 swap into the Reatta featured in the webpage link provided earlier in this thread. Allow me to answer some of the questions that have come up in this thread thus far.

The owner of this vehicle approached me a while back about doing this swap and said he wasn't too concerned if the ECC became non-functional since he had interest in upgrading to the later IPC/BCM setup that comes in the (1990?-91) Reatta's.

I went ahead and did the swap using the 94-95 Bonneville/Riviera 3800 PCM since I have tuned many of these PCM's to work with the Series II SC engines. I also re-used the original Reatta engine computer harness and just changed connectors and added wires for the electronic trans. Yes, the IPC and ECC does still function; but as mentioned earlier, the temp and tachometer gauges don't work, nor does the fuel mileage computer function. The A/C doesn't work either because the ECC sends out an A/C request command over the serial data bus, but the 94-95 PCM's never had this function available (94-95 Riviera's used a seperate a/c request wire). I do have a plan to wire in a simple toggle switch in the ashtray or other owner preferred location as a last resort IF the PCM-serial data communications issue cannot be resolved. The speedo and odometer register correctly because these functions got a 4000ppm signal input from the original ECM (which the 94-95 PCM also supplies).

At some point the owner intends to switch over to the newer Reatta IPC/BCM/HVAC head, etc. If at that point we could not get the 94-95 PCM to interface with these components, we could always swap in the 92-93 3800SC PCM which will work with the 4T60-E trans and the (90?-91) Reatta IPC/BCM/HVAC, etc. The only difference would be the EGR valve type. Worse case scenario, I could have an adapter plate made at a machine shop so the early 3-solenoid EGR could be used on the Series 2 engine.

Until we get to that point, I am still doing research to see if anything can be done with the 94-95 PCM to get it to communicate with the earlier Reatta electronics. I have emailed <span style="font-weight: bold">padgett</span> all the info I have on ECM/PCM serial data message schedulers and perhaps something can be found. But as of right now, the owner is enjoying his new-found power and the 94-95 PCM's serial data line is NOT connected to the Reatta (otherwise the IPC and ECC will flip out because of a miscommunication error).

I would be happy to answer any questions about this swap any of you may have.

-Ryan G.

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<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Just the Northstar engine and trans = big bucks

4.9 engine and tran = about 600-1000

</div></div>

Not to bash either of these engines but people who have done the Northstar swap into Fieros have experienced PCM issues because currently there is NO tuning out for them. Without the other caddy electronics present, the engine tends to operate in limp-mode so full power cannot be realized. Those who have worked around this in the Fiero community have only gotten the Northstar engines to perform on the same level as a stock or near-stock 3800 Series II SC engine in the same type of vehicle.

The 4.9 caddy engine has also been done, both fuel injected and some have even elected to go carbed. However, most I have seen have only churned out performance numbers marginally better than the stock 2.8L V6 that comes in the Fiero. Certainly not as fast as a stock Northstar or 3800IISC. There are a couple of people in the Fiero community who have managed to get custom cams made and even added turbos to the 4.9, but still the fastest ones cannot touch a highly modded 3800 Series II SC.

For now it appears the best engine [in my opinion] (most reliable and most power potential) to use for a swap is the 3800 Series II SC. Cheaper to come by than the Northstar, and much cheaper to mod and install into a Reatta than either caddy V8, it would be my engine of choice for a swap...unless of course you can't live without the V8 sound...or horrible gas mileage that comes with it smirk.gif .

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<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> The engine builder blamed the damage on Knock. </div></div>

This is exactly why experienced GTP/Regal GS modders will tell newbies the first "mod" to be purchased is a scan tool to monitor knock. It seems modding the Series II S/C motor is all about making sure you eliminate/reduce knock as much as possible, and check for any changes after each mod made.

So far, I havent touched mine yet. But CAI, new downpipe/u-bend delete, colder plugs, and either a 3.5 or 3.4 pulley would be a good start if I could get the dough together.

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<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> <div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> The engine builder blamed the damage on Knock. </div></div>

This is exactly why experienced GTP/Regal GS modders will tell newbies the first "mod" to be purchased is a scan tool to monitor knock. It seems modding the Series II S/C motor is all about making sure you eliminate/reduce knock as much as possible, and check for any changes after each mod made.

So far, I havent touched mine yet. But CAI, new downpipe/u-bend delete, colder plugs, and either a 3.5 or 3.4 pulley would be a good start if I could get the dough together. </div></div>

I don't understand why so many in the L67 community choose to ignore the lessons learned over a decade ago by the Turbo Buick community. One of the first mods any of those guys do (including myself) was to purchase and install a Casper's KNOCK WARNING gauge kit. This gauge has several LED's that light up sequentually whenever a knock is "heard". For the L67, you will need to purchase the "stand-alone" knock gauge kit. However, I believe it is worth it. Not like you can watch a small number on a scan tool while you are performing a WOT excursion...much easier to stick a gauge near your line-of-sight. http://www.casperselectronics.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=gp38sc

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I have nothing against boosted engines, just believe they belong at 30,000 feet. That said we made several PROMs with different advance maps to use for experimentation. One had the same advance curve as the 94 L-67 PROM, another had a slightly more aggressive one.

We also had the evidently mistaken belief that the built in knock-retard function would compensate for detonation. I suspect that it was but the damage was being done in the cycle that cause the detonation as the knock retard only occurs after the first few detonations are experienced.

Thanks to GMTuners I now have both ECM and BCM data streams for what looks like 88, 89, 90, and possibly 91. I had some of this before but not the BCM pieces. Thank you very much.

So we have just made a quantum leap forward in data but it still must be reduced to information which is not a trivial task.

As for the a/c issue, it might be possible to drive the compressor from the BCM rather than the ECM using the Twilight Sentinel relay (which the Reatta does not use). Of course my idea to use the TCC line to control the s/c bypass did not work at all so no promises.

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<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">

We also had the evidently mistaken belief that the built in knock-retard function would compensate for detonation. I suspect that it was but the damage was being done in the cycle that cause the detonation as the knock retard only occurs after the first few detonations are experienced.

</div></div>

Yea, thats the whole problem with the system. Detonation must occur BEFORE the PCM can retard timing. And to add a litte bit of info on your timing tables, keep in mind the 94-95 SC engines have a taller block and longer connecting rods than the Series 2 engines, therefore the piston dwell time at TDC is longer which has an effect on ignition timing. Also, the Series 1 engines have less effecient flowing heads than the Series 2 engines. I have compared stock timing tables between the Series 2 SC and Series 1 SC engines and they are different. The Series 2 engine appears to not want as much timing advance as the Series 1 engines.

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"The Series 2 engine appears to not want as much timing advance as the Series 1 engines."

That would go along with better chamber filling leading to faster flame propagation.

Spark advance has always been a somewhat mystical function that tries to create peak chamber pressure at the "sweet spot" around 12 degrees ATDC. *Everything* going on in the engine focusses on that one event. *Everything* going on in the engine affects where that is.

Is hard enough for a normally aspirated engine but is multipled when you start talking about boost. And that is just about power.

Detonation is a whole 'nother ball of wax since there are two main differences in octane:

1) how fast the fuel burns (at standard conditions)

2) at what temperature/pressure does "spontaneous combustion" occur

This means that an engine designed for 87 PON will have less hp with 93 PON since the "premium" fuel burns slower and needs more advance.

You aggravate both (temperature and pressure go up) with boost.

Things get a lot more involved fast but those are the basics.

GM used to have what was called "Standard test #20 - Maximum power and detonation" where you found out on a carfully instrumented dyno just where the limits for the advance curve and then they would back off a couple of percent for longetivity since an engine will not last long there (but will feel great while it does). Of course the marketeers usually used the test 20 figures in the advt's.

So how you build an engine depends on what you want. For me that means 200k miles on 87 PON for my street cars which is one end. The Judge is a wee bit closer to the limit. Must admit that my sole experience with boost was a Fitch Sprint quite a few years ago, have always believed "There ain't no substiture for cubic inches." (must admit that some of the rice burners today are impressive - 1000 hp from 2 liters seems incredible. Once ?)

Then there are four different supercharged 3800s (not even going to get into turbos though intercooling is easier with a turbo) ? 92-93 Series 1 (digital EGR), 94-95 Series 1 (linear EGR), 96-02 OBD2, and the new series III ?

Imagine I would know more if was a real mechanic instead of a hobbyist.

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Dont know much about that knock warning guage, but the scan tool will allow you to track more than just knock, and download results for later analysis and comparison to previous runs. Scan tool will show you throughout your 0-100 mph run (or whatever speed you choose for the run) when knock occurs and how much. And being able to look at other parameters can clue you into what might be happening, not just "do I have knock or not". autotap offers a scan tool for either linking into a laptop or your PDA. LS1M also works with PDAs. Given the price of entry for these is only $110.00 more, I know which one I'd choose.

I'm not sure what lessons the L67 crowd hasn't learned. Look at ZZPerformance , 3800 Performance , or Intense Racing . All of these vendors have figured out various aspects of the L67 to the point that there are actually step-by-step recipies for properly modding an existing L67 car depending on how far you want to go.

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<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Dont know much about that knock warning guage, but the scan tool will allow you to track more than just knock, and download results for later analysis and comparison to previous runs.

</div></div>

Very true, BUT you have to be watching the scan tool readout to know WHEN you are getting knock. Try focusing on a relatively small number on an LCD screen while you are blazing down the road at WOT. Not very safe. I prefer to actually have a gauge with bright LED's light up when something is happening. The knock gauge I use looks like this:

3gauge.jpg

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">

I'm not sure what lessons the L67 crowd hasn't learned. Look at ZZPerformance , 3800 Performance , or Intense Racing . All of these vendors have figured out various aspects of the L67 to the point that there are actually step-by-step recipies for properly modding an existing L67 car depending on how far you want to go. </div></div>

No offense to any of the vendors you mentioned but each have spent a lot of money in trial/error finding out what works and what doesn't. Most of the time they are reluctant to give out this info, rather they would prefer you just buy their product without explaination. Furthermore, most haven't even tried different ideas or even acknowledged the lessons learned by the Turbo Buick community over a decade ago. I know this because I have talked to a few of these vendors directly. The most common response I got from them was "thats a different engine that what we are using so what works for them, won't work for us". I don't know about you but thats a pretty poor attitude to have towards history when the engine you are using is based off that technology.

Don't get me wrong; ZZP, Intense, and the others have brought some very useful products to market for the 3800 that we would not otherwise have. All I am saying is, at least up until recently, NONE of these vendors advocated the use of a knock warning gauge. Go over to turbobuick.com and ask around and you will find out that is one of the first upgrades to get applied to a Turbo Buick after it is purchased. In my opinion, shortsightedness and ignorance of history is bad for business.

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