quote Originally posted by jetsnvettes2000: whats the diffrence between the 3800 and the 3900? I was lookin on craigslist and I found a 3900 w trani for 400 bucks

just about everything.

They are both GM v6's. They might even have some of the same "universal" type sensors GM uses on more than one engine. Other than that, they have nothing in common.

The 3800 is a 90* V6 and to my knowledge doesn't really have anything in common with any other GM v6's. I've *heard* it's based off a buick V8 but never looked into it.

The 3900 is one of the newest evolution in the 60* v6 line. You know, like the 2.8's that came in fieros.

Thoughts on the HX35's? They are a dime a dozen.

Well, this is a kind of loaded question. My Fiero is modied, but not for "race". That being said, my LS4 Fiero has a respectable 0-60 time. But the sound is a great deal of the "experiance"
Realistically, there just is not a lot of cars on the road that can spank me. Not around here at least.

quote Originally posted by TheRealShadowX: Nope, no question mark.

You just didnt read it right........

quote Originally posted by jetsnvettes2000: whats the diffrence between the 3800 and the 3900? I was lookin on craigslist and I found a 3900 w trani for 400 bucks

60° DOHC vs a 90° OHV that's totally bulletproof.

what about the turbos in the saabs? too small? what if I ran 2?

quote Originally posted by jetsnvettes2000: what about the turbos in the saabs? too small? what if I ran 2?

You might want to use something like this calculator.

Just slapping turbos on an engine won't necessarily lead to optimal results.

[This message has been edited by Xyster (edited 09-01-2011).]

quote Originally posted by jetsnvettes2000: what about the turbos in the saabs? too small? what if I ran 2?

2 is dumb

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Turbo 3800 E85 5spd spec5
11.53@126.7

quote Originally posted by Justinbart: 2 is dumb

Can you elaborate please? Personally I believe, in some applications, twin turbos could be a better choice than a single. Heck, Bugatti even uses quad turbo configurations and BMW is toying with the idea of a tri-turbo M3.

quote Originally posted by Xyster: Can you elaborate please? Personally I believe, in some applications, twin turbos could be a better choice than a single. Heck, Bugatti even uses quad turbo configurations and BMW is toying with the idea of a tri-turbo M3.

Try making a manifold for a W16 that feeds into 1 turbo.....TT is just for the wow factor really. A single turbo system can support up to 2500HP. With the single turbo system you get simplicity in plumbing, less cost, weight savings, less....well everything.

quote Originally posted by 87antuzzi: less....well everything.

Except lag... if you want huge power, that is.

quote Originally posted by skuzzbomer: Except lag... if you want huge power, that is.

That's what I was hinting at.

quote Originally posted by skuzzbomer: Except lag... if you want huge power, that is.

2 stage and a half ass knowledge on what you're building. I was running a HX35 on a volvo 4cyl....with launch control the word "lag" does not even register. And with VGT turbos lag is a thing of the past. Full boost under 2k. Look at DH, and Justinbarts car. Both are blazing fast with 1 turbo.....

quote Originally posted by Xyster: That's what I was hinting at.

I know.

quote Originally posted by 87antuzzi: 2 stage and a half ass knowledge on what you're building. I was running a HX35 on a volvo 4cyl....with launch control the word "lag" does not even register. And with VGT turbos lag is a thing of the past. Full boost under 2k. Look at DH, and Justinbarts car. Both are blazing fast with 1 turbo.....

You were talking 2500HP... not 500. To get that power, you'd need a snail the size of the president's ego.

[This message has been edited by skuzzbomer (edited 09-01-2011).]

OMG...BUT HOW?!?!?! Making boost without going anywhere on a single turbo. IMPOSSIBLE!!!!

quote Originally posted by 87antuzzi: Simply said a single turbo could support 2500HP. I said nothing about the size of the turbo its self. Anyways, OP is not wanting 2500 HP out of his fiero. He is wanting a fast fiero. He mentioned TT and there are plenty reasons not to go with a TT set up. A HX35 will spool plenty quick and if properly built will destroy a lot of cars on the road. If you want to debate twins VS singles start a new thread.

I know and I don't, so that isn't going to happen.

You brought up the numbers from the outset... I didn't.

quote Originally posted by Xyster: Can you elaborate please? Personally I believe, in some applications, twin turbos could be a better choice than a single. Heck, Bugatti even uses quad turbo configurations and BMW is toying with the idea of a tri-turbo M3.

87antuzzi said it well. Sometimes I think that the term "Lag" was made up to determine the people that know turbos and those that know nothing. For instance; a supercharger is going to lag 10x more than a properly sized turbo.

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Turbo 3800 E85 5spd spec5
11.53@126.7

quote Originally posted by Justinbart: "...a supercharger is going to lag..."

Even though I have seen this so many times on stock L67s and know it's true; part of me still doesn't want to believe it.

quote Originally posted by Justinbart: 87antuzzi said it well. Sometimes I think that the term "Lag" was made up to determine the people that know turbos and those that know nothing. For instance; a supercharger is going to lag 10x more than a properly sized turbo.

quote http://en.wikipedia.org/wik...versus_turbocharging The main advantage of an engine with a mechanically driven supercharger is better throttle response, as well as the ability to reach full-boost pressure instantaneously. With the latest turbocharging technology, throttle response on turbocharged cars is nearly as good as with mechanically powered superchargers, but the existing lag time is still considered a major drawback, especially considering that the vast majority of mechanically driven superchargers are now driven off clutched pulleys, much like an air compressor.

[This message has been edited by Silentassassin185 (edited 09-01-2011).]

Lets quote wikipedia to prove a point against people that convert supercharged cars to turbo.... whoo!

Not trying to prove a point. This is how I've always understood it. If I'm mistaken in my understand I'd be happy to listen to how its wrong.

Ok so a single turbo but.... I was reading that some of the super cars like the avero aero run dual small turbos just because they spool up faster due to well it being a smaller mass to spin ? seems logical to me kinda?? what is a vgt turbo anyway ? im turbo dumb remember I needs sum schoolin!

quote Originally posted by jetsnvettes2000: Ok so a single turbo but.... I was reading that some of the super cars like the avero aero run dual small turbos just because they spool up faster due to well it being a smaller mass to spin ? seems logical to me kinda?? what is a vgt turbo anyway ? im turbo dumb remember I needs sum schoolin!

A correctly sized turbo wont lag out on you. Lets say some dude in a vette is revving on you at a stop light. You give him the good ol head nod and fire up the 2 step. Light turns green and you dump the clutch. You are spooling your max boost when the clutch dumps. In other words you simply "**** and get". So from a stop light you dont have any lag if your set up correctly. Now lets say the same guy comes up while on the freeway and you are scooting along. You look up and are on 1/4th normal PSI. You either brake boost or down shift. Regardless both are almost instant boost. From a lets say 60 to 140 pull I would start (my volvo) in 3rd gear and get on the brakes and floor it. Get the boost up, honk 3 times and it was a race. That was on a 4cyl Volvo so no matter what i was going to have a slow spool unless I went to a larger head. On the 3800 you are simply moving more air at once out of the exhaust. A VGT (variable geometry turbochargers) will change the turbines to increase boost at lower RPM. You dont need a VGT I was simply saying lag on a single turbo is a thing of the past.
This is brake boosting

I have an antilag button on my shifter that says "full boost" on it... I basically just hit the button, floor it, and release the button when I want to go.... very little to no brakes involved.

quote Originally posted by darkhorizon: I have an antilag button on my shifter that says "full boost" on it... I basically just hit the button, floor it, and release the button when I want to go.... very little to no brakes involved.

ok cool so how does it work?

quote Originally posted by jetsnvettes2000: ok cool so how does it work?

it wouldnt be fun competing for the fastest fiero if I gave away ALL my tricks...

quote Originally posted by Justinbart: 87antuzzi said it well. Sometimes I think that the term "Lag" was made up to determine the people that know turbos and those that know nothing. For instance; a supercharger is going to lag 10x more than a properly sized turbo.

Uhhh, no.

quote Originally posted by pmbrunelle: Uhhh, no.

Drive a car with a Centrifugal super charger and get back to me.

quote Originally posted by 87antuzzi: Drive a car with a Centrifugal super charger and get back to me.

Lag is not equivalent to manifold pressure as a function of RPM in steady state.

[This message has been edited by pmbrunelle (edited 09-03-2011).]

quote Originally posted by pmbrunelle: Lag is not equivalent to manifold pressure as a function of RPM in steady state.

"lag" is the time it takes to get boost. Not MAX psi. Superchargers dont produce boost at idle. So you have vac. Lag is the time the vac decreases and becomes positive. So superchargers and turbos both have lag.

quote Originally posted by 87antuzzi: "lag" is the time it takes to get boost. Not MAX psi. Superchargers dont produce boost at idle. So you have vac. Lag is the time the vac decreases and becomes positive. So superchargers and turbos both have lag.

In the turbo community....

Spool time = the time it takes to go from less than 1psi, to 1 psi of boost.

Lag time = The time it takes to go from 1psi to peak boost.

quote Originally posted by 87antuzzi: Drive a car with a Centrifugal super charger and get back to me.

You like to keep bringing up arguments no one else is talking about, like the 2500 HP engine and now this.

We are talking about fieros, that are modified, stay within that topic please.

Turbo's will lag with a manual off the line, unless there is some way to actually load the engine you'd like to share (note I said off the line), and since we do drive like normal people from time to time, I'm also not talking about revving the engine to 4,000 RPM and dropping the clutch.

If you are cruising in 5th gear, and just want some extra pull, a turbo will lag getting to max boost without the airflow of higher RPM's (and this is fine since we are cruising).

Drive a 1980's mustang SVO and get back to me BTW.

Roots and whipple supercharges I have always been told don't lag, you push on the throttle, it's making 8 PSI (or whatever it is set for). Now I haven't driven one, but if enough of you tell me it takes 3 seconds for that to happen I'll believe you.

Now what I have done is driving several turbo cars (including a twin turbo 300 zx, with GT series ball bearing turbos), and a few diesel turbos.

Guess what? Even the jetta TDI, and international 4900 (DT466e) had lag, not a lot, but I could feel the turbo spin up faster over a 1-3 second time frame. Now, this is driving like a normal person, not revving to 4,000 RPM and dropping the clutch, but seriously we can talk about normal driving as well as racing.

I won't get into centrifugal superchargers for 2 reasons, ALMOST no one has one on this forum, and it's a well known fact that the make more boost as the engine goes faster. So it's not terribly relevant to this conversation.

[This message has been edited by cooguyfish (edited 09-03-2011).]

quote Originally posted by 87antuzzi: OMG...BUT HOW?!?!?! Making boost without going anywhere on a single turbo. IMPOSSIBLE!!!!

It probably has an anti-lag device. I used 2 in my turbo 2.5 SOHC Mopar with a GT3582R. The 1st one was done by ECM. On decel it would retard timing and dump more fuel on a certain rpm window, this would create exposions and made the turbo spin out of control resulting in instant boost. The 2nd one I installed a spark plug between the head and the turbo and used a flame thrower trigger device activated with a button at the steering wheel. Both work great but the exhaust system couldn't handle the heat. Rally cars use it.

All this talk about turbo v supercharger and nobody even noticed that the electric turbo gives FREE boost and can make MASSIVE power....LOL

Lol oooo how about I just add a snorkle and point it into the wind and drive faster!

turbo ecotec 2.2 with wiseco pistons eagle rods 20G hahn setup :

i have run times on my scanner of 5.3 0-60 .still not tuned up for max HP but i really think a turbo 3800 auto is the best setup for 0-60 times .my car is built more for cornering , not straight line speed .with a little more tuning and some practice i will be in the high 4's .only running 10 psi as of now .