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139K views 238 replies 45 participants last post by  Capt Fiero 
#1 · (Edited)
Okay folks, it's getting close to crunch time with the turbocharger...Had you thinking, huh?

Anyways, this project is still a little off from actually starting, but I now have most of the pieces in place for the project to begin.

4.9 turbocharger, stage one indicates that the turbo will be placed on an existing engine/transmission combo without an actual rebuild. I will be running no more than 6 psi of boost, and will try to get away with not using an intercooler. We'll see how it works out. I am well aware what this might mean for my engine and tranny, but I feel that it will be good for tuning purposes in the long run for the second stage...

The 4.9 turbocharger, stage two, will include the 4.9 liter Cadillac engine (4.5 was considered for a split second) with ported/polished heads and intake; possibly more cam; new moly-chrome piston rings and general rebuild specifications. Overall, the stage two engine will be pumping around 260hp/300lb.ft naturally aspirated. I will add about 8 psi of intercooled boost which will make the engine perform in the 360hp range...I hope.

The second stage transaxle will be rebuilt and bullit proof and I will attempt to have a 3.73:1 final drive ratio. I have to study the tranny more, but I hope I can make those aforementioned changes.

So back to stage one. I have the following items for this project:

GM-3 IHI 6.5 liter diesel turbocharger. It is used and will probably need a rebuild in the bearing area, but for $76.00, I couldn't pass it up. I'll let everyone know if it needs a rebuild or not when I get it next week via UPS.

I have the MSD boost timing controll system with an MSD digital-6 ignition. These items will help combustion and timing while under boost.

I have two Deville exhaust manifolds (front and rear) and a cross-over pipe. They need some welding and an adapter fabricated for the turbo to attach to, but this won't be an issue...I hope.

Auxiliary fuel system minus the actual controlls (piggy-back ECM). I am going to do one of two things here: use an old TBI system for extra fuel needs; or I will make a new fuel log and use two or more auxiliary fuel injectors for fuel needs. An extra fuel pump and some cutting will be necessary, but they're taken care of...Minus the cutting of the fuel tank.

I am going to go with the Megasquirt system for now, which will set me back by a couple hundred (actually $140.00 for the complete DIY kit)...Unless someone hacks the Caddy ECM before I purchase it.

Extra exhaust tubing. I have plenty around in the garage I have just rented. It shouldn't be an issue.

That's it for now as far as supplies. I will also add a bypass valve so that the boost won't blow anything up when I take the pedal off the floor. And perhaps an electronic wastegateb to keep good controll of the boost I'll be running, which will be considered a rather small amount...We'll see how that works out.

As for the general reader: there are only a select few people here on this form who's technical advice will be heeded. They know who they are, and are welcome to help me out if possible. If you don't have anything positive to say, then don't say it: this is my project and I'll won't listen to your negatron views! :nyanya:

I am not concerned if people think this is a crazy idea: I don't care and if you don't have any good technical advice, read on...If you decide to flame or otherwise put this project down, I simply will not respond: your opinion won't even be considered valid. If you have valid advice and/or comments, type away. Remember, this is a community project that everyone will enjoy in the end. People want to see this done and IT WILL BE DONE!

That's it for now. This thread will be here for a while, and may even get burried due to my personal time constraints, but I'll keep everyone posted and will post pics of the items and project as soon as I recive more space for attachments.
 
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#203 ·
I read this thread as well I think you guys are over complicating it. This isn't 1985 people are putting turbos on everything imaginable. I guess your main obstacle is probably budget. I would look seriously at running a rear mount turbo. There is room to run a 2" charge tube back up alongside the exhaust and into the TB. On my 92 there is plenty of room for an underhood turbo where the airbox is, but bringing in the exhaust from both banks and then having room to run the turbo exhaust back out would be very problematic. I just don't see a lot of other paths to get a 2.5" pipe out of there. Even if you built your own manifolds which would be overkill for this application that wouldn't help. The rear mount turbo solves a lot of packaging and heat problems and since hte point (at least for me) would be to maintain the cadillac off idle torque and use the turbo to beef up the midrange and top end any increased lag is not an issue. Rear mounts are being used in all sorts of applications and while lag is slightly larger than a front mount its not a huge issue. Lag has never been a big issue on V8 turbo apps anyway.

With the CAd ecu tied into so many functions and it works so well with all its diagnostics, my plan would be to use a Megasquirt to run 2 extra injectors in the inlet tube before the throttle body. They also sell other standalone injector drivers, but you will need to interrupt and change the timing as well and the MS can do that as well, and give you some datalogging. Connect a wide band to it and you should be able to put a good tune on it.

Anyway, just rambling, I"m not gonna turbo my CAdillac because the whole point of it is to be a no hassle daily driver. I keep telling myself, hot rod your hot rod, and leave the Cadillac alone !
 
#204 ·
You're overcomplicating things yourself, seeing as how the stock injectors will support 300whp with a turbo. This has been proven by the guys with turbo 4.9's running 300whp with stock injectors.

Illumina doesn't come around here much anymore but the turbo Seville project is still being worked on as far as I know.
 
#205 ·
You will need larger injectors.

Reason: Under boost the injectors see boost pressure, so if you have stock 18 lb/hr injectors @ 43.5 psi, and you boost 6 psi, you have 16.7 lb/hr flow under boost. So you need to do a boost a pump deal or put in fatter injectors. But you will need to get 80 psi on the injectors to overcome the boost referenced reduction in fuel flow. 80. That is like 6 bar! Going up 1 bar is ok, but 3 bar? That is too much for stock parts and FPR.

So you WILL need fat injectors, at LEAST LT1 injectors to handle it. BUT you enter in new problems, you can't adjust the fuel injector constant on the 4.5L/4.9L PEFI ECM's (maybe Ed Wright has hacked it, or call Lyndon Wester). I haven't had time to mess with hacking it as I don't have a 4.9L car anymore (I do take donations!), so I can't hack away at it.

There is a lot of issues. Fuel is a dangerous one. Adding a MSII might end up being the best. My idea of a single extra injector in the airflow. Like add a injector TBI unit to the intake in place of the stock TB, and trigger it only in boosted conditions. You can add as much fuel as you could ever need. I personally would inject E85 in, but that is me...

Going boosted takes some serious thought. ANY amount of boost is a big boon to power. Even 2 psi is significant. Think of it this way, at BEST you can suck 1 BAR air into the engine, honestly a zillion factors here. But at even 2 psi boost, you are 1.1-1.2 bar, and at a lower rpm. So you are seeing your 300 cubic inches fully utilized at a much lower rpm (you don't see all inches used at anything less than WOT, if throttled, you are at less than fully used displacement...)

Can you turbo stock injectors? Yes, but I wouldn't without additional fuel delivery.
 
#206 ·
So I guess the guy with the turbo 4.9 Fiero who told me he was running stock injectors told me wrong? His motor, as of the last time I spoke with him, had made over 300 1/4 mile passes (and was making over 300whp and close to if not more than 400ft/lbs) and never had a problem with the motor.
 
#207 ·
He might be, but there is likely something he isn't telling you too. Either extra fuel adder somewhere or he isn't making the power he claims. Honestly, 300 hp on the rear wheels? That is a low 13 sec car. Or better. I would expect better than that. If not, he isn't making the power he claims. Have him stick a WB O2 on and make a quarter mile run and show you. Either he is running lean as heck, he isn't making near the power he claims (how much boost?), or he is running something extra like methanol injection to keep things sane.

My 301 Turbo pushed my 4030 lb Trans AM to 14.21@97.3 mph and that was a calculated 290 rwhp. Now put that in a lighter car, with more cam, a better turbo design (mine was awful), much better gearing, etc. That car should be darn close to 12's.

And you have to REALLY watch boost on stock hypereutectic pistons. They will crack. And what happens then sucks.... I melted #7 down on my 301 Turbo. And that was a well factory modified Q-Jet, 800 CFM, super rich "DX" rods and I STILL leaned out and lunched a piston.
 
#210 ·
I still am pondering turbo/E85ing my LT1..... $$....
 
#211 ·
Damn people!

I have not forgotten about this project, but it has been placed on hold because of many other things. In the last year, I have purchased a new home, I have been promoted at work, I have been trying to wrap up school, and have been dealing with other automotive related things not concerning this forum. I should also note that the transmission on the Seville took a nose dive to Hell and that has also been a factor in not completing this project; the tranny will be done with a nice LSD however!

Now for the good news...

Since I have become more settled in my house, I will be getting back to the project soon. I don't really want to put a time table on this because I have some home projects to do too, but I have all the pieces necessary to build this project. I'm not going to say what route I am taking either, but I will say this: everyone who gave me credible input in this thread will get credit where do! I want the final results to be a total surprise...I will give a small hint however: I do have a complete Allante intake setup, fuel injectors included... :D

Also, Tom, where the Hell are ya going dude??!! Hit me a PM and give me your new email before you leave if you'd like, I want to talk more about my ideas here!!!

All that said, please bear with me on this thing for a little while longer!
 
#213 ·
I wouldn't push the boost too hard with stock pistons. Even the LT1's only can handle 6 psi before things start coming out in pieces....And they were meant to be abused....

I would look seriously into o-ringing the block or heads. A big limit is going to be the stock head gaskets, no performance once available. Even the 301 Turbo V8's got o-ringed gaskets..... and I blew 2 sets of them....But I beat the Mustang both times..... :)
 
#214 ·
I really really really really REALLY wish that people would stop using words like "The ____ engine can only handle __ psi before it breaks." tuning is a HUGE part of whether or not something breaks and all turbos are NOT created equal. 6 psi on a GT12 is not the same 6 psi on a GT60. You need to think about VOLUME when you're describing or discussing turbos. That is why the flow maps are so important when you start turbocharging something that isn't normally turbocharged. Take one small T3 60 trim (largest of the Garrrett T3 before TO4B and TO4E) turbo on a 130-150 ci engine and you may see 300 hp on 18 psi at the point where the turbo is stretched thin and being overworked. Take that same engine and use a TO4B or TO4E and you may see 300 hp on 6-8psi with the turbo barely being used. Now that that same TO4B or E and put it on an engine twice the size and it's the same deal...you need engine to make boost and you need turbo to make power. A small engine isnt going to be too happy with a large turbo the same way a large engine with a small turbo is. Bottom line is that all turbos arent created equal and you CANNOT SAY that "___psi is the highest you can go on stock internals" unless you're describing WHICH TURBO AS WELL. Go back to my posts on the GM that he's thinking of using. The turbo itself maxes out at barely 440 cfm and is capable of running 20 psi but running that much boost on that small turbo will do one thing, create heat, and make it that much harder to tune. You really need to think of your HP GOAL before you think or buy your turbo.

As for what psi an engine fails at...they all fail at some point. I recently tuned a 1.6L B16 (Honda) engine that made 550+ hp on a GT35 turbo with stock internals. To some, the ignorant (still stuck on web forums being keyboard racers) are still stuck in the mindset of "The B16 can only handle 6 psi on stock internal and maybe 200 hp before the rods bend" well guess what...mine was on 26 psi. Tuning is key and knowing which turbo when you say things like ___psi.
 
#215 ·
I understand where you're coming from on this. Personally, I don't plan to run 33.4 psi because that is not what I'm after - I want about a 400 HP street cruiser that weighs 3500 lbs and can roll with most of what's out there while still riding and looking like a Cadillac should...with a few suspension adjustments to prevent rear-end squat and shit like that.

I don't plan on being one of those guys that has something unpractical for use, so when I say that I want 400 HP on a built engine, then I am likely looking at 7-9 psi of boost on top of an engine that has a mild cam, port and polish, Allante intake and other gadgets (I pretty much have the aforementioned items I need there at that)...

That said, the project is still taking a bit of time. House is going through quite a few changes, but I have a new 4.9 liter ($65 from junkyard half-price day!) that I am working on with a few neat surprises in store, including my device for forced induction. The transmission is also done and will likely get a run this weekend to see what needs to be done there - upgraded 3.33 FDR with an LSD, beefier internals, shift improvements, and a Superchip for this transmission combo that I actually found in a junkyard! It is from a 1992 STS with the 3.33 FDR...

Updates soon, I promise!!!
 
#216 ·
Cool! Killer price on the 4.9!

The idea is NOT to explode the engine the first time boost is hit. So with cast pistons and a bottom end never intending to see boost, keeping it low below 10 psi is crucial.

Illumina, I might have an intercooler for you, PM me.... It is in flux, but possible....
 
#217 ·
Again, not necessarily. The pressure being put in isnt as important as the volume of air being put in at that given pressure. You need to specify which turbo and which volume (how much CFM at given psi) when you're discussing which psi. If you have a turbo that doesnt flow enough volume no matter what psi you're run it at, you don't have much to worry about when it comes to pistons melting, cracking or rods bending. I'll give you this example using the stock MX6 2.2L F2T engine and the stock RHB5 VJ11 turbocharger. The max CFM that this engine is capable of at redline (6,000 rpm) is 235 CFM and that is at 100% VE. The turbo itself is barely capable of 200-250CFM per the flow map. The stock boost on this turbo is 8.7 psi but even if you raise the boost to 20 psi (max) it still isnt enough flow to reduce the AFR from rich to lean. Even at 20 psi the AFR is still pig rich in the 11's. Bottom line, if your turbo is sized accordingly, you don't have nearly as much to worry about. The GM series that he is looking at is sized accordingly for this engine, psi, engine CID, RPM, and target power output. You cannot say ___ psi will ruin the engine when you don't which turbo. Generically saying ___ psi, or "Stay under ___ pis and you'll be okay" doesnt work if you don't mention volume at that specified PSI.

I will say this, most engines can handle at least half an atmosphere (6-8 psi) which is a good start regardless of which turbo it is. I will agree with you there, but the rest no. We're kind of on the same page.

EDIT: PS- I don't come here often, WTF is Casino cash? lol
 
#218 ·
I got you.... I have heard the LT1 can only take 6 psi, more than that they have real problems with the hypereutectic pistons breaking.
 
#219 ·
Just mentioning I am still kicking around, I pop in hear and look around every now and again.

My 4.9 is still running great, however I am now getting ready to install my 8th yes eighth transaxle. I managed to blow up the Centerforce Dual Friction clutch I had in the car as well. I have a new Clutchnet clutch that is suppose to be able to handle 450lbs of torque. I am building a custom one off 4spd standard transaxle for the car, with much better gearing for the 4.9's torque. It has a 3.32 gearset with a .73 overdrive 4th.

I do still have a turbo sitting here for the 4.9 but am not sure if I am ever going to get around to installing "it". I still plan a Turbo at some point however the turbo I have is way too big for the motor. It was almost a gag joke that I got it. Its from a Kenworth Tractor. Yes as in long haul tractor. So it should be good for uhm 20-30psi on a 6L+ V8. The inlet is so big, it looks like it could swallow a wooden 2x4 and spit it out the other side.

As for the Turbo 4.9 Fiero. It was modified a fair bit, however for the most part, the engine and fuel system was stock. Custom ECM, and such. I know he had A LOT of passes on that motor and nothing ever failed, it was actually built for his wife and she ran the hell out of that car.

I belive it was a high 12 second car IIRC. I would have to double check the records to make sure. I think there car was in the 3000lb range.
 
#220 · (Edited)
Ok, so I'm bored and need to talk turbos on a cadillac...

What are you planning on doing for engine management? I ask because it would be real straigtforward and easy to install a MegaSquirt, especially since these cars are non-OBD-II which makes sensor feedback to the ECU a moot point. I wish I had my 1990 Eldo near me, it's 1000 miles away in storage as I'd set it up for all to see...

Easiest way to do it is a remote mount turbo, I'd use a Holset HY35 or HX35, 40, etc... series (on the HX you'd have to hog out the turbine split scroll header) for test purposes since they're cheap as dirt (good used one off a couple year old truck usually runs $250 range, only run oil as a lubricant/coolant (no bearings)), in line oil pump ($150), oil lines ($50) some exhaust piping ($100), weld on some hangars(or bolt on if welder not available). Return would be cheaper aluminized steel pipe ($50), for couplers use heater 'stick' hose ($50) for large diesel rigs instead of Silicone because it's much cheaper and much more durable, t-bolt clamps ($50), a cheap ($85) ebay intercooler up front, $300 to build your own Meqasquirt w/a 3-bar MAP sensor, stimulator kit (to bench test that it's working prior to vehicle install), and LC-1 Wideband O2 ($100). You'd also need an external wastegate if you only wanted to run ~5-7lbs of boost which will set you back another $100.

I'm surprised no one has bothered doing this yet, it's so easy it's comical, the turbo system would take a day at most to plumb up and install, the MS would take a couple hours each night x a week for a novice to build, prolly a few sessions like that to install, and then a few more sessions like that to get it idle and then tune. I can't begin to believe no one has considered this, it could be done for about $1300, definatley under $1500...
 
#221 ·
New details have emerged in that there is a 4.9 tuner that can pretty much eliminate about $1000+ worth of crap that was needed before hand.

I have just been busy with so many other things that I simply haven't had time to do this yet.

Please stay tuned as this whole thing will be a pleasant surprise!
 
#228 · (Edited)
Will have to look into it. Give me some time, I don't have a 4.9L to look at right now, need to scare up some good underhood picts.

The trans may not live long, swapping to a 4T65E-HD from a SC Buick would be highly recommended. A 4T80E would love the abuse even more....And we know it fits.

the question is how much the 4.9L can handle.....

http://www.drivetrain.com/frontwheeldrive/fwdpositraction.html will help a lot.

IIRC you don't need to remove the trans to install the diff, so if you (Illumina!) have a LSD to drop in, GO FOR IT!
 
#232 ·
Hey guys, long long time no chat. I'll start a separate thread so I don't jack this one, but figured you might like to see this link. He is one of our Local Fiero's with the Caddy 4.9 in his Fiero and is going to toss a 4.5 into one of his other Fiero's but the kicker is that it will be Turbo'ed, Page 4 has most of the Turbo related stuff. He was going to use a nice tiny turbo, for quick spool, however the 4.9 in a Fiero all most makes too much torque down low. So a tiny turbo would have been the wrong way to go, he has since decided on a much larger unit that won't spool until at least 2500rpms. Then keep the boost set around 10psi all the way to the top.

Well here is the link, http://westcoastfieros.com/forum/forum_posts.asp?TID=207&PN=1&TPN=4 http://westcoastfieros.com/forum/forum_posts.asp?TID=207&PN=1&TPN=4
 
#235 ·
mines already efi its a 90 4.5pfi . it seams to share alot of the same parts that the 4.9 dose all except for the trans is about the only thing i can think of that is different right off the top of my head . so now the question is could i just use a ecm out of a 91 and use an electronically controlled trans. but heck while im at if it would fit ide just throw a 4.9 in there and call it a day
 
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