This is why you don't buy someone else's project. They will go out and spend $900 on pistons and other parts and leave the stock connecting rods. This motor was FAR from stock, and couldn't daily drive. Took me a good week just to take it passed half throttle lol!
Heres how it happend... Lined up against a 06 GTO cammed out. First race ever since I had the swap. I had a good 2 cars on him without shifting hard or red lining it, shifted to 3rd and the car started acting funny. On the way back to our hangout spot my oil pressure started dropping. I turned the car off and let it sit for a good hour letting it cool down, and check the engine out. Only thing I found wrong at the time was the vac line going to my fuel pressure regulator blew off. It was 3AM and I wanted to get the car home (>2miles away) and deal with it the next day. Started her up and got a slight knock. Drove it out of the lot and got onto the main road going 20mph babying the car. Shut it off 3 different times within a mile cause the knock was getting worse. I turned it off at a stop light while it was red. Started her back up, going about 5mph threw the light when I hear a loud "clunk", then the car comes to a complete stop. Motor was locked up
So with no more motivation for the car, it sat in my driveway for a good month without me even touching it lol. Well, I got the motor out yesterday and found this

At the time I was running a 3.0 pulley on water/meth injection

My plans now are to get a low low mile SIII 3800SC, leave it basically stock. Get the air ride on the back along with a clean paint job and rims. That way I'll have a very clean 12/13sec Fiero I can daily drive.


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My build thread:
https://www.fiero.nl/forum/Forum1/HTML/059538.html

[This message has been edited by greengoblin0129 (edited 08-12-2007).]

Oh Ouch! Sorry to hear about you car. So it was a stock bottom end or were there some upgrades?

Nolan

I guess a rod decided to make a timely exit?

quote Originally posted by Sourmug: Oh Ouch! Sorry to hear about you car. So it was a stock bottom end or were there some upgrades? Nolan

Had comp bolts to 20 over forged diamond coated pistons. All the mods are in my sig

You are running a 3.0" pulley and no intercooler- IMO a formula for disaster. Events like this are the reason that I always stress scanning, scanning and more scanning. Then you can clearly see the KR numbers and with HP Tuners or DHP software you can adjust the fueling and timing accordingly. Now your engine did have water/alcohol injection and this would seem your safeguard against detonation, but it seems like the system didn't quite get it done.
The 3800Sc engine is a very reliable and strong engine, but detonation can blow apart even the strongest of engines. It sounds like detonation did this engine in so a regular scan and a PCM adjustment might have saved you oodles of work and lots of money. Even with a new stock 380SC engine scanning is a good idea.

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87GT 3.4 Turbo- 0-60 5.2 seconds
2006 3800SC Series III swap in progress
Engine Controls, PCM goodies,
re-programming & odd electronics stuff
" I'M ON THE LOOSE WITHOUT THE JUICE "

It could have been detonation. Its also making a lot of power on stock rods which could also been the cause of failure. I'm a fan of tuning on a dyno for this reason. When you know its not detonation that killed it then you can figure out what the weak link was in the engine.

Good kill, the GTO not the motor

[This message has been edited by crzyone (edited 08-12-2007).]

quote Originally posted by Dennis LaGrua: You are running a 3.0" pulley and no intercooler- IMO a formula for disaster. Events like this are the reason that I always stress scanning, scanning and more scanning. Then you can clearly see the KR numbers and with HP Tuners or DHP software you can adjust the fueling and timing accordingly. Now your engine did have water/alcohol injection and this would seem your safeguard against detonation, but it seems like the system didn't quite get it done. The 3800Sc engine is a very reliable and strong engine, but detonation can blow apart even the strongest of engines. It sounds like detonation did this engine in so a regular scan and a PCM adjustment might have saved you oodles of work and lots of money. Even with a new stock 380SC engine scanning is a good idea.

I had previously had some pcm issues. It kept loosing the tune, had recently got that problem fixed a week before this happened. I had the scanner on it earlier that day for a good 60 miles. Everything looked great and it was running perfect, so figure it was good to take it out that night. I ran the 3.2 pulley without the water/meth, and the 3.0 with it.

Honestly though, you knew you were losing pressure, you knew you had a knock, suck up your pride, call it a late night, and have the thing towed. Could have saved your motor.

i forgot what happens if your vac line falls off your regulator you get a bunch of gas or very little plus then you had a vac leak. I also have to say water/meth injection is useless on a 3800 motor. there is a reason no one runs it. (no one in the top 100 l67 times anyway)

the stock bottom end holds up way over your power level i think you have to tear it down before you have any idea what happened

If you lost the reference line for the fuel pressure regulator, you would have been running very lean under boost. This would have caused detonation and the destruction that followed.

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62 Buick Special
86 GT, 5-Speed
87 GT, 3.4l DOHC Turbo 415 HP @ wheels
88 Toyota Supra Turbo

quote Originally posted by Matt Hawkins: If you lost the reference line for the fuel pressure regulator, you would have been running very lean under boost. This would have caused detonation and the destruction that followed.

Actually, the vac line just lowers the psi when the motor i idle. I did a little experiment with my swap for just this reason, my car runs like 5-6% rich at idle and perfectly fine at wot, with the FPR line off. Its not like a "FMU" its just a variable regulator that GM thought would be needed for a nice idle. the L67 injectors were the largest they have ever put into a car (they still are IIRC aside from direct injection stuff), so the regulator just turned it down at idle.

His pulley size was MORE than large enough for his setup, without intercooling or anything. My friends with just XP cams have no problems daily driving on 2.9/3.0's.

More pics of the damage

wow that thing really grenaded.... holy mackrol....

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WOW!! i have to say thats the first time i have seen that makes me rethink the rods i was going to put into my build

quote Originally posted by darkhorizon: Actually, the vac line just lowers the psi when the motor i idle. I did a little experiment with my swap for just this reason, my car runs like 5-6% rich at idle and perfectly fine at wot, with the FPR line off. Its not like a "FMU" its just a variable regulator that GM thought would be needed for a nice idle. the L67 injectors were the largest they have ever put into a car (they still are IIRC aside from direct injection stuff), so the regulator just turned it down at idle. His pulley size was MORE than large enough for his setup, without intercooling or anything. My friends with just XP cams have no problems daily driving on 2.9/3.0's.

The reason for the manifold pressure reference is to keep the same delta pressure at all times. If absolute fuel pressure is meant to be 45 psi, you will have less at a "gauge" reading when idling. This would show a pressure lower than 45 psi. If the engine was boosted to 10 psi, the fuel pressure reading would be 55 psi. If this came off, you would have less fuel pressure and less fuel in the engine. Engine go bang.

WOW! What kind of HP were you getting out of that engine before it blew?

quote Originally posted by Formula88: WOW! What kind of HP were you getting out of that engine before it blew?

As most of you remember, this is the engine from the "3800SC Fiero runs a 10.90" thread that 99% of members on here called BS lol. The guy snapped the timing chain, and I purchased the motor from him and put on a new chain, valves, and gaskets/seals... and cleaned it up a LOT. It was estimated at 400HP/450TQ.

[This message has been edited by greengoblin0129 (edited 08-14-2007).]

is there any way they where using a l36 block and rods?

hmm when ever you're running below a 3.25 best bet is to have an IC its constantly flowing and its a sure thing.

yes you can run a 3.0 with a cam but why chance it, best to just safe guard yourself and have an IC. Specially on those blistering 90+ degree days. I've been running a 3.0 for a couple years now and I'm not exactly easy on the car.

I'm still skeptical on the whole water/meth injection. You pay to play, IC's aren't cheap, but they get the job done and effectively.

sorry to hear on your luck.. does suck to pop a motor.
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3800 SC/IC Formula whines more than your girl...

[This message has been edited by LoW_KeY (edited 08-14-2007).]

quote Originally posted by chrisgtp: is there any way they where using a l36 block and rods?

I looked at the #'s on the rod that broke, and they are the same as the rods in other L67 motor. From what I've heard, the L32 rods are stronger?

This whole issue comes from an highly modded motor that was untuned and possibly not put together correcty. The bottom end of a L-67 can handle up to 600HP and that has been proven by a few vendors. I am willing to bet this started from denotation and it went down hill from there. Good luck with the reuild.

quote Originally posted by MstangsBware: This whole issue comes from an highly modded motor that was untuned and possibly not put together correcty. The bottom end of a L-67 can handle up to 600HP and that has been proven by a few vendors. I am willing to bet this started from denotation and it went down hill from there. Good luck with the reuild.

It was put together my Hoosier Performance, a shop in Indianapolis that pretty much only touched 3800 motors. The guy went cheap on the timing chain and connecting rods, the shop just put it together.

I talk to Morad Parts Company today... They are shipping my new engine out this week!!!!!!!!!!!! It's out of a 2002 Buick Regal with only 40K miles on it!!! Leaving it bone stock for the most part, daily driving it, and finishing the rest of the car. Meanwhile building up another engine.

quote Originally posted by greengoblin0129: It was put together my Hoosier Performance, a shop in Indianapolis that pretty much only touched 3800 motors. The guy went cheap on the timing chain and connecting rods, the shop just put it together. I talk to Morad Parts Company today... They are shipping my new engine out this week!!!!!!!!!!!! It's out of a 2002 Buick Regal with only 40K miles on it!!! Leaving it bone stock for the most part, daily driving it, and finishing the rest of the car. Meanwhile building up another engine.

I think that was the Miller "Call of the Night". (Hey, football is back!)

It should make for a great daily driver, and you should be able to "play" at the track (occassionally) too!

Greg

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The pistons in the car were just able to handle the knocking, and the rods were not. I would imagine that if this was a normal stock bottom end, a piston would of failed before the rod did.

Pistons are never an reason to justify running a poor setup, you will just find the next weakest part when you start knocking. If you were not going nuts on that car when you were scanning/tuning, as you mentioned this was the first time you got on it hard, then it comes at no surprise that it exploded. Tuning XPZ's have been considered some of the hardest things to do even by experienced tuners with 2 years experience under their belt.

I HIGHLY doubt that the vac line falling off caused this damage. It was either severe knock, or oiling, neither of which would be directly caused by EXTRA fuel at idle (unless the trims adjusted enough to subtract alot of fuel at wide open).


Weak connecting rods are not the cause of this failure, it was another reason, mostlikely knock or bearing failure.

[This message has been edited by darkhorizon (edited 08-14-2007).]

I have been told that there is a HIGH failure rate on block rebuilds on 3800sc engines. That's why people like ZZP uses the stock bottom ends. Are you selling your mods, like the cam and heads?

quote Originally posted by vallen11: I have been told that there is a HIGH failure rate on block rebuilds on 3800sc engines. That's why people like ZZP uses the stock bottom ends. Are you selling your mods, like the cam and heads?

Yep. My GM Goodwrench rebuilt long block from the dealer lasted less than 10,000 miles before blowing smoke bad on decel. JUNK.

Now I'm building a slightly used stock engine.

MOBILE

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Member MN Fieros Forever
Self Installed SC3800/getrag. 13 years in Car Audio and Car Electronics Experiance........ 19"s.. w/ 13" Brakes all around.