Dad mentioned a motor swap project...

[Guest F14CRAZY]

Howdy folks. The age old question...

My dad mentioned that when we sell the Claret convertible (currently in autotrader) we should pickup a half decent Reatta (being that this is Lansing, they're not tooo difficult to find). One with a bad motor or tranny or obnoxiously high miles or something. Then have our buddy Craig Clark (who does stuff like top out crotch rockets and build Porsche powered dune buggies) do the swap for us. He'll have to do some fabrication and wiring but that's his problem, right? Will probably get a '90-1 to avoid the ECC.

Scrouge has a great RWD idea, but we'd keep this FWD/automatic to keep things kinda simple. But, what motor should be implemented? It doesn't have to be insanely fast but at least 200 hp would get the Reatta moving.

L67/3800 supercharged series II: I raced a '00 era 4 door GTP with my mom's Durango and blew it out, so I don't like this motor much . Would probably be simplest since it's the same block

3.5L DOHC Intrigue/ Aurora motor; 215hp

4.0L DOHC V8 Aurora motor; 250 hp would make things fun, but can a V8 fit in the engine bay?

Northstar; 300hp. For millenia, men (and women) have tried to gain more power. This would satisfy them . But would be bigger than the 4.0, right?

I swear I won't make another post about this again, but I just had to ask

Would seem easiest to use the tranny included with whatever motor

[Guest F14CRAZY]

Other thoughts...

Greg Ross' series 1 supercharged 3800 (Park Avenue motor?): would be most similar to the Reatta's stock motor. What's the HP rating of these?

3.4L DOHC; 90s W-body motor: I read that these were built to put out around 280-300hp but were toned down to a bit over 200 because of tranny problems. Can these be "toned up"? Said to be in the ECM.

3.8L turbo Regal GN; can these be modified to sit sideways?

[Guest F14CRAZY]

Cadillac 4.1, 4.5, 4.9?; not really performance tuned, but still a V8. 4.9L may be too big for the engine bay.

[Guest F14CRAZY]

Just looked up the old Caddy motors and they don't have enough power to justify the swap...

4.1L in the Allante: 170 hp (Reatta has 165 )

4.5L in the Allante again: 200 hp (probably too big anyway)

[Guest F14CRAZY]

Just read about newer Cadillac motors like in the CTS. 3.2L and a 3.6L DOHC

[Bob]

You like talking to yourself?

Have you ever drove a SeriesII SC? Real fun motor, great low end torque.

The Oldsmobile DOHC motors are a blast at high speeds and high rpms but have no low end to them.

Go test drive a Regal GS and I bet you can make a decision.

[juddev]

I believe that the reatta has the correct engine mount holes for the cad 4.9 already.

The 4.9 will fit fine and weigh less because it is aluminum.

Check out this page

http://www.tyre.serveftp.com/mycitations/

[Guest Robi]

One thing to keep in mind for this is the computer that will have to go along with the engine. In that same vein, ... keep the engine and transaxle together. The computer probably controls the transmission too so don't make it too difficult. My thoughts have always been, get the shop manual for the car the engine/transaxle came from and use it to figure out what sensors will be needed to get things to work properly and where ypou will need to put them in the new installation. I've been toying with this in the context of a Marauder Replicar CANAM car with a 300 HP Northstar.

[Guest F14CRAZY]

Haha it does sound like I'm talking to myself

Wikipedia article on Caddy V8s

This is what I'm getting my facts from...

The Caddy 4.9L would be at 200 hp and 275 ft/pounds or wtf you call them. My '89 3800 is rated at 165 hp and 210 ft/pounds. Hmmm...it's a V8 and indeed has more power. And it sounds like it'll fit. And consider that this was also used in the Allante (besides the 4.1L and Northstar), which is on the E-platform, which is the same as the Reatta so this would probably be more or less easy and probably why the 4.9 would bolt up to our present tranny.

And from the link a gentleman provided here it looks like forced induction is possible.

This may work. Any other comments? Thanks for the posts back

[padgett]

"Will probably get a '90-1 to avoid the ECC" - still have the problem of the digital dash and HVAC which require the BCM. It expects a specific 8192 baud serial data stream (P4 and NOT OBD-II) from the ECM with the info so to eliminate the computer issue you would need to also build a new dash and possibly (not certain) reprogam the HVAC.

Not impossible, just difficult. If you want to keep the dash best stick to a 1994 or earlier powertrain (hint: Northstar came out in 1993).

[Guest F14CRAZY]

But Padgett...say we go with the Caddy 4.9. Wouldn't the engine controls be handled by the ECM (donated from the appropriate caddy) and leave the Reatta BCM? Or do they communicate with each other enough that compatibility is a problem...?

If we went with an early 90s Caddy, would that have a digital dash? I'm not hoping for it to have the same connectors and be working perfectly in seconds, but I'm hoping that there's enough similarities between Buick and Caddy electronics of the same eras to make things no as complicated

[padgett]

The engine parameter displayed on the 90-91 dash are generated by the ECM and passed as a serial data stream (the ALDL link) to the BCM which creates the data display.

This is the same stream used by scan tools and the differences are why every tool requires you to tell it what year and engine code (and sometimes subquestions like car or truck) before it can display information.

[Guest F14CRAZY]

Would the '92 or so Caddy ECM have a significantly different data stream to the BCM compared with the stock Reatta 3800 ECM? I don't think GM would have dumped that much money into making totally different computer interfaces/languages

Never done anything like this before so I don't know exactly what's going on; apologies.

Caddys had auto climate control so I'd think that maybe the Caddy BCM would jive with it (my "easy" diagnostic manual, actually for Caddys, gives the same directions as for Reattas like how to extract error codes). Would it be possible for the Caddy ECM and BCM to work with the Reatta HVAC? And again, how about with the dash?

The other gentleman was right and a dealer service manual would help a lot right now

[2seater]

The Caddy 4.9 has been done before and it does fit. I don't rememember who had this conversion and it was a few years ago that it was on this forum.

[Guest F14CRAZY]

I searched and a 4.9L has been mentioned but didn't have much in details, except they did say it fit in nicely

[Guest tempest68]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">L67/3800 supercharged series II: I raced a '00 era 4 door GTP with my mom's Durango and blew it out, so I don't like this motor much . </div></div>

Based on just one race?

I like the 240 h.p. stock, and knowing that aftermarket to hop it up is there too. If you're into wrenching on your own car to improve its performance, this is a good motor to start with. Mid-to-high 14's stock, 13's are fairly easy for only alittle dough, 12's are obtainable for deeper pockets, and a select few have reached 11's and even 10's. Just check out zzperformance.com or intense-racing.com and read up on what this motor is capable of. Also see 3800performance.com for other goodies.

There is a good forum on clubgp.com too. The Racing section can be interesting to see who wins/looses to whom/what.

Just something to think about, anyways.

But whatever motor you select, I'm sure we'd all like to see pictures or even a video once its done. And even better if you (or your hired-hand) has the time, take photos/video of the entire process and document it.

[padgett]

It is not the data rate or speed - all P4 systems (roughly 1987 to 1994) are 8192 baud serial streams. It is eactly what order the bytes are in that changes for every model. On one car the first data byte might be the MAP. One another, the MAF.

A particular engine code may be the same from year to year (I have used an 88 cartrige to scan owr 90 Bonneville, the "C" engine data stram was the same) but different codes have difference sequences and it is just a string of bytes, no identifiers.

Keep in mind that the first C3 computers (1981-1988) used a 160 baud data rate and just did not have time for anything more than the data bytes. GM didn't change something that works.

[Guest F14CRAZY]

I was mostly just messin about the GTP . 240 hp versus a big 345 hp V8, whether in a body on frame truck or not...and there's tons of GTPs running around Lansing. Almost seems like a generic motor but since it would be in a Reatta it would be special anyway.

Padgett: I think I understand what you're talking about with the computer data bus.

And yes, I would fully document everything. I'm interested in the 4.9L idea since it sounds like it's a more or less bolt in swap. I could probably pull it off myself with a bunch of time. Most I've done before was put another transmission (manual) in my '92 Ford Explorer (4x2) which took a really long Friday, Saturday, and Sunday to pull off.

It sounds like the 4.9L is a durable motor and would take forced induction but I understand that there's a large after-market with the L67, though we're not looking to build an insanely fast Reatta. 4.9L would probably cost less (like from a salvage yard) since their a little older and probably plentiful. And the tranny being able to bolt up is a plus. Hell, would the 4.9L fit in the motor mounts and bolt in to the engine compartment? Again, I'm basing this on the fact the Allante had this motor and was also based on the E-platform. Maybe I'd need the Allante mounts. Hell I don't know. I'm talking to myself again

[Jibby]

Not to put a damper on things, F14, but that motor has had it notorieties. Now, anyone who takes care of their motor, knows, that it won't die. But that Cadillac V8, will die, if not taken care of, like it was your own child. The Cadillacs that they came in, died long before the motor did, anyhow. Just giving you a heads-up, on what I've experienced, as well as a few other select individuals. The Allante only survives, because it was a sound design.

[padgett]

Had some experience with the Allante message board. Think it survives because enough people are willing to throw enough money at it.

[VicW]

When I first got my Reatta I found an Eldorado 1990 with a V-8 at the junk yard. So mounts and things are accessable at not Allante prices. A donor car is probably easily/cheaply found. A Sedan DeVille would work also. Since they both had the Teves in some vehicles and the used market for old Caddies tend to not pay attention to the Teves with due diligence, wrecked ones are all over.

However, I wonder if that path is any easier than going with the 3800 upgrades available. Since you are currently looking for relatively modest increases, 20 to 50 HP the L67 path would yield an enhanced Reatta, not a cloned/ sexy Eldorado.

An aftermarket conversion/ interface module for the electronics might find a market (hint hint) and be an interesting learning project. Example a PDA programmed to plug into the ADL stream. Data in processed and injected back with the SC data. Since the Supercharger is only a few additional circuits a another small module and a "chip" could be added in for that. A project idea that life's requirements keep moving down the list.

Vic

[Guest F14CRAZY]

Hmmmm...

The best thing, if I was going to do the 4.9L, would be to have my dad's buddy (deals in used cars and collision) get me an Eldo or similar car from a wholesale auction. Hell can probably get one for like $500 or something (he once bought an '89 Rivi than ran and drove for $75; an awesome deal for some Reatta compatible parts). This would be easier than a junkyard since I'd have ALL the parts, and all of it in front of me. When I get done I could simply call the junkyard and have them take the rest of the wreckage unless one of you guys wants a 3800 powered Eldo

The jump from 165 to 200 HP would be a decent, feel-able gain along with the torque plus other simple mods like a chip, intake, exhaust, etc. But yeah the L67 has the aftermarket support which I can't at all deny. Though from what I understand, the L67 computer language is a lot farther off from the original Reatta data stream, than the 4.9L would be. And that motor is going to cost more (find me a GTP or Rivi for $500 ). I could probably mess with the wiring myself if I knew what I was doing or had a manual that said what to do (which doesn't exist). I'm in training to be A+ certified so I know electronics well, but this isn't plug and play .

Thanks for the additional posts. Last night I talked to my buddy Mario and he's selling his '95 Regal 4 door (with the coveted TPI) to buy a '96 Mustang GT. I'm trying to talk him out of it and get him to get a rare '96 Regal 2 door which would have the series II. Then he could upgrade to an L67. Then I'd probably have to upgrade to an L67.

[Guest F14CRAZY]

I googled and found a page that discusses the 4.9L and L67

some Caddy forum

One posted said that in the same car, the 4.9L and L67 (without mods) are about dead even

[padgett]

One other factor - the L67 requires premium gas, traditionally 20% more than regular.

[luftweg]

I don't understand that one couldn't use the existing engine and drivetrain (or one from an identical Reatta... say my '88 parts car) build it up with more performance in mind, and then add an external centrifugal supercharger?

All the old wiring would remain intact, and the only real big issue mounting the SC and routing it into the intake...

As long as the bottom/drivetrain was beefed enough, and the boost not too deadly, it should work out -- shouldn't it?

Of course, as Padgett I think has said, it would require a 'tuner' to tweak it...

K

[padgett]

ittle more than that, the advance curves now have to resond t boost as well as vacuum, the current MAF program tops out at 170 gm/sec and a bosted engine is liable to flow more, and some sort of wastegate control needs to be added.

For that reason I would begin with the 92-94 L67 computer which already has those things (and a digital egr) and tweak the data stream to match the installed BCM. Would need to remove the E-trans program unless going to use one as well (4T65E is stronger than a 4T60).

Not trivial but is doable.

[luftweg]

If it were practical, a group of 4 or 5 of us who are looking into doing an engine/drivetrain mod should combine efforts ...

For this to work best, we should pretty much do the exact same things to our cars...

For example, if it was a 3800 SC Series II and getrag swap, then we would ALL do that same swap....

All the difficulties could be shared and the costs could be lowered for all of us...

K

[Jibby]

Regarding Allante:

Bwa ha ha ha ha ha ha!

Somebody is trying to sell a DEAD one, around here. I can't remember where I saw it, could've been Jersey... I just remember that it looked like it had been "through the war of 1812 and back".

[Guest F14CRAZY]

I'd only mess with a Northstar Allante

[Machiner 55]

There's an excellent article on Cadillac's '06 440hp Supercharged 4.4L Northstar V-8 on pg 108 of the May 2005 issue of Hot Rod magazine. You may have to go to the local public library to view a copy since it's about 5 months old already.

[Guest F14CRAZY]

Probably a $10k motor

[Guest F14CRAZY]

I'm gonna do some more research on it, but I got thinking...if I were to actually do an entire motor/tranny swap, why settle for the 4.9L when I could use a Northstar? The 4.9's 200 hp is more than the Reatta's 165, but you're going to feel the difference between 165 and 300

[Songman]

You might find some good stuff over at Pennock's Fiero Forum. Just about every swap in the world has been done over there, from Quad4s to Northstars. I know the Fiero is a good bit different than the Reatta because of the digital gauges and stuff, but there are folks over there who have gone so far as to be running OBD III in their cars. One friend of mine who lives about 45 minutes from here is running a 3.5 Shortstar from a 94 Old Aurora in a Fiero. He uses all of the electronics from the Aurora and it is a beautiful install. The install looks totally stock and it even passed California emissions. (Picture attached)

Pennock's is at http://www.fiero.nl

[Franbev]

Didn't a guy in Minnesota put a Caddy 4.9 in a Reatta a few years ago? I remember it was for sale on this board.

[Tinker]

Here's a thread from summer 2001 about that 4.9 caddy in a Reatta .

[Guest F14CRAZY]

I did find that post in a search I made a while back. No writeup, no photos...doesn't help much except to show it's possible.

[tc11003]

to tell the truth , the one major thing we all have in common is the understanding that our reattas came with an almost bulletproof engine. this was no accident. at the time 165 hp and 220 pound ft of torque were excellent numbers. yes, today they are pale , but in 89 ( mine is an 89) that was terrific. in fact 0-60 times of 8.9 seconds were muscle car numbers in those days. to swap out our 3.8 for something else makes little sense to me, just my .02 worth.

[padgett]

Well I have no doubt the series II is a better engine, over 30 mpg on the road is common. That said the original 3800 was designed for the context of a 55 mph national speed limit and in the 50-60 mph range is superb.

Might not that the torque peak of the SII is about the same (210 lb-ft vs 220 lb-ft) and the higher horsepower results from moving the torque curve to a higher RPM and not any real increase.

[Guest F14CRAZY]

I agree that 3800s internal parts are great. They're long lasting engines. The bad thing is that with the age and milage of Reattas, everything else goes to pot (sensors, interruptors, alternators, water pumps, etc).

The series II with 200 some horsepower out of the same block and without forced induction is better yet. The Reatta would have been much better off if this motor existed when the Reatta was in production.

GM management cut the Reatta down a lot. Remember, that it was first conceived as a muscle car with the turbo 3.8 but got toned down. Which is why we're stuck with Teves

[89REATTAJIM]

May have found an engine for you: