Turbo Charged 4.0L BII Build

[Will]

Of course there is, colder air is denser air...cooler charge air is denser than warmer charge air......intercooler means cooler charge air (if done post turbo preintake) and denser air is good.

Yes, but there is a lot of resistance in an intercooler, and a lot of volume is added. So the balace point where the air is getting hot enough that it's actually worth cooling it is about 10psi. If you don't run over 10psi in 90% or your driving, you are wasting your money buying and installing one--and you will see worse throttle response and less power at less then full power because of the added resistance and volume.

Some contruction equipment where throttle response needs to be very crisp doesn't use an intercooler even with much higher boost pressures.

 

[nate12346]

Yes, but there is a lot of resistance in an intercooler, and a lot of volume is added. So the balace point where the air is getting hot enough that it's actually worth cooling it is about 10psi. If you don't run over 10psi in 90% or your driving, you are wasting your money buying and installing one--and you will see worse throttle response and less power at less then full power because of the added resistance and volume.

Some contruction equipment where throttle response needs to be very crisp doesn't use an intercooler even with much higher boost pressures.

The main reason why I didn't pick one up and they were all too big lol

 

[crazy horse]

I no nothing about what you're talking about with the turbo stuff, but I do know that the ford racing 19lb. injectors will fit, that's if you are looking to add bigger injectors.

good stuff going here

 

[burningRANGERtires]

Yes, but there is a lot of resistance in an intercooler, and a lot of volume is added. So the balace point where the air is getting hot enough that it's actually worth cooling it is about 10psi. If you don't run over 10psi in 90% or your driving, you are wasting your money buying and installing one--and you will see worse throttle response and less power at less then full power because of the added resistance and volume.

Some contruction equipment where throttle response needs to be very crisp doesn't use an intercooler even with much higher boost pressures.

where did you get 10psi.. it would completely depend on the engine and turbo. on sentras at 6 psi from a t28 we needed a intercooler, but it was one hell of a small one. i agree theres resistance but also theres a lot to gain from a intercooler. just dont buy them huge ricer intercoolers.

also im trying to think of any factory turbo'd car that isnt intercoolered.

The main reason why I didn't pick one up and they were all too big lol

why didnt you pick on up from like a audi 1.8t or an old probe gt (theres always a few on craigslist in my area for 20 bucks). their pretty small and go on the driver side of the bumper (i dont know if this applies to the BII but on my ranger i have a tranny cooler on the passenger side).

 

[nate12346]

where did you get 10psi.. it would completely depend on the engine and turbo. on sentras at 6 psi from a t28 we needed a intercooler, but it was one hell of a small one. i agree theres resistance but also theres a lot to gain from a intercooler. just dont buy them huge ricer intercoolers.

also im trying to think of any factory turbo'd car that isnt intercoolered.



why didnt you pick on up from like a audi 1.8t or an old probe gt (theres always a few on craigslist in my area for 20 bucks). their pretty small and go on the driver side of the bumper (i dont know if this applies to the BII but on my ranger i have a tranny cooler on the passenger side).

When I was at the junk yard I found an Audi and the intercooler was too big for my app. I had a 1999 VW passat for a while and it had a driver side wheel well mounted intercooler that seemed really small... Ill look for one again, but for now we will see how it does without one.

I know all the turbo Chryslers didn't run intercoolers

 

[Evan]

Of course there is, colder air is denser air...cooler charge air is denser than warmer charge air......intercooler means cooler charge air (if done post turbo preintake) and denser air is good.

An intercooler is used to stop detonation. It nets you no power. A 5-psi system with an intercooler will produce the same power as a 5-psi system without an intercooler. Now, if you wanted to dial up to 10-psi and experienced detonation, you'd install an intercooler. The intercooler would keep the air being forced into the cylinder cool, and therefore decrease the likelyhood of early detonation.

Cooling the air between the turbo and the engine still yields the same amount of air.

From Superchargersonline: "Essentially, run an intercooler when only when running peak boost (i.e. any more boost would cause detonation) for the octane of fuel you use."

 

[86freebie]

now i am no expert, but i know colder air does give you more power.
i saw a show where they piped a\c air through the intake on a diesel truck and it was impressive how much more power. until the a/c could not keep up any more.
that is why dragsters are happy with cold air

 

[Evan]

now i am no expert, but i know colder air does give you more power.
i saw a show where they piped a\c air through the intake on a diesel truck and it was impressive how much more power. until the a/c could not keep up any more.
that is why dragsters are happy with cold air

Cold air at the initial intake (before the MAF) gives you more power, as the air is less dense and allows you to fit more molecules through the same volume. But an intercooler sits between the turbo and engine.

 

[JohnnyU]

also im trying to think of any factory turbo'd car that isnt intercoolered.

"Intercoolered"?

Many of the early Mopar turbo 4cyl's were not intercooled. The first generation of Dodge Diesels and were not intercooled. Many of your high-end, high-dollar pulling trucks/tractors are also not intercooled. Water/meth injection sure, but no ATAC.

 

[nate12346]

We are all arguing the same answer lol.... YES Denser(colder) air is more power. Im turbocharging a stock internals 4.0L. Not some massively built Subaru STI engine. The turbo forces more air into the same amount of space.... More Oxygen = More power.

Whatever oxygen my intake pulls in, is how much is going into the engine. Since I'm building a snorkel it is going to be as cold as it can get. Yes when you compress air heat is made...Heat from the engine bay as it goes to the throttle body could expand it more.

SO! In theory I am getting the exact amount of cold dense air that is sucked in, but it would be in higher boost levels because the warmer air expands once it has been pressurized.

Im not too worried about the small amount of power loss due to heat(expansion). And its not going to be nearly hot enough to make the engine detonate.

 

[Bent Bolt]

also im trying to think of any factory turbo'd car that isnt intercoolered.

1980 Firebird with a carb'ed 301 turbo

 

[nate12346]

HAHA I just figured something out. It has been pissin me off. My boost gauge never really sat right at zero. It is always a little below. I kept tapping it to see if it would go back to zero. Then I looked at where it was made (Mexico). They are pretty much at sea level in most places. I am up at about 7000 feet. They zeroed the gauge down there and when it got up here the less pressure dropped it below zero lol

 

[turbo cat]

hey man i got your message over there. I joined up to see what you can do with that sucker. Oh and yes a 4.0 can hold up to high boost here is my 91 4.0 single t3 pushing 15psi

it needs to be tuned for the 15psi as i cant lay into it hard at 15 but at 5psi it drives great everyday with no detonation. i do need new remanufactured heads as i think mine are starting to crack again

 

[nate12346]

hey man i got your message over there. I joined up to see what you can do with that sucker. Oh and yes a 4.0 can hold up to high boost here is my 91 4.0 single t3 pushing 15psi

it needs to be tuned for the 15psi as i cant lay into it hard at 15 but at 5psi it drives great everyday with no detonation. i do need new remanufactured heads as i think mine are starting to crack again

SWEET MAN! Good to have you over here!
This guy has been helpin me with a few of my questions. Thank you for the help

 

[Evan]

it needs to be tuned for the 15psi as i cant lay into it hard at 15 but at 5psi it drives great everyday with no detonation. i do need new remanufactured heads as i think mine are starting to crack again

Cool!

Do you have the turbo connected to just the driver's side exhaust?

What kind of HP gain do you see with 5-psi? It would be interesting to see a dyno sheet.

Looks good man!