Intercoolers are SWEET!

[R.O.R-2.0]

so, i recently added an intercooler from a mazda mellinia (has to be the smallest IC on the face of the planet) to my rabbit.

before i added it, the car would peak at ~25 psi.. now i see no more than 15 psi on a hard pull, so i imagine its restrictive to some point. intake used to get burning hot also, now it stays cool, i cant get the intake to heat up no matter what ive tried..

i really wish i had a pyro, so i could see the exact effects it had on my engine..

engine seems to be more responsive on the bottom end now. it was sorta laggy right after i added the intercooler, then i either got used to it, or the lag went away..

but it still has quite a bit more power than before. i like how less boost = more power.. i also turned up my fuel screw about 3/4 of a turn, thats probably where most of the new power came from. but it still smokes about the same as if it were non-intercooled, so i know the cool, dense air is helping out, just limited by the tiny intercooler is all..

next time i will probably be using one of those A2W IC's like what Josh bought from FROZENBOOST.. i like how compact those are, and its super easy to mount a 3/4" heat exchanger in front of the radiator.. alot easier than a whole intercooler core..

another thing ive been wondering..

do intercoolers improve mileage? they should right? since the engine is getting cool air..

[8v-of-fury]

Wont be increasing mileage with the turned up fuel and your heavy foot Kev

[bajacalal]

I have one from a Saab 900S on mine, it's pretty compact as well though it makes the air do a u-turn in it.  I think it makes a difference in peak power and engine heat, I'm not sure about mileage... Mine is also lagging until the turbo spools up.

How much fabrication is needed to fit that one?

[R.O.R-2.0]

I have one from a Saab 900S on mine, it's pretty compact as well though it makes the air do a u-turn in it.  I think it makes a difference in peak power and engine heat, I'm not sure about mileage... Mine is also lagging until the turbo spools up.

How much fabrication is needed to fit that one?

the way ive got it rigged up, it didnt take much fab work.. i mounted it so that i didnt have to modify my core support..

its not that pretty, but its functional.

[dodger21]

Is the boost point before or after the cooler?

I am thinking that if it is after, and you did NOT downsize piping to make the cooler fit, then it is working.

25psi of 380* hot air may have the density of air at 15psi with it being 120*...

In the Cummins world, guys were pushing 40+ psi with no cooler. After adding a large, stock cooler, they were lucky to see 30psi with the same charger.

[R.O.R-2.0]

Is the boost point before or after the cooler?

I am thinking that if it is after, and you did NOT downsize piping to make the cooler fit, then it is working.

25psi of 380* hot air may have the density of air at 15psi with it being 120*...

In the Cummins world, guys were pushing 40+ psi with no cooler. After adding a large, stock cooler, they were lucky to see 30psi with the same charger.

i read boost directly from the intake mani..

no, i already have small charge piping.. i didnt go any smaller, no.

i imagine i lost some boost because of the nature of an intercooler (makes the air smaller) but mostly because its restrictive..
core dimensions are like 9" long, 4" tall, and 1.5" thick..

like i said, its a tiny little bugger..

[RabbitJockey]

10psi is a big jump, are you sure that intercooler doesn't leak or something

[R.O.R-2.0]

10psi is a big jump, are you sure that intercooler doesn't leak or something

yea, im sure. boost leaks are very appearent on my car.. when its got a boost leak, the turbo barely makes any boost, and it takes about 5 minutes to build boost..

[dodger21]

That doesn't mean you might not have a pin hole or 2. Did you have it pressure tested?

For the sake of arguement. If the cooler doesn't neck down at all, all the clamps are good, you either have a really good working cooler or a couple of pin holes. The only reason it would be restrictive is either when it necks down, it is clogged, or you have holes.

[RabbitJockey]

yeah i just can't see a 10 psi different from just adding an intercooler even if it is restrictive, theres no way its that restrictive that it almost cuts your boost in half

[macka]

if its too small for the turbo, it will restrict flow.

[dodger21]

It is possible. What was the lbs/min on the Mazda? And whats the lbs/min on your turbo?

[R.O.R-2.0]

It is possible. What was the lbs/min on the Mazda? And whats the lbs/min on your turbo?

lmao? i have NO idea..

came off a supercharged miller cycle 2.5 V6 engine.. it does neck down from the size of the boost tubing tho.

i would peak 20 (25 psi on a hard long pull) usually.. now it peaks at 15-16, and is snappy..

when i added my volvo intercooler to my other rabbit, it didnt drop my boost 4-8 psi..

[blackdogvan]

I'd put some money on you having a boost leak. Have you tried a pressure test?

[R.O.R-2.0]

I'd put some money on you having a boost leak. Have you tried a pressure test?

i would put some money on me not having one.. i know what my car feels like with a boost leak big enough to let out 10 psi boost.. its laggy, and smokey as hell..

right now its snappy, and my boost gauge is still responsive.

i will check it out, but i really DOUBT that i got leaks. this intercooler is just super duper tiny. it only has 7 or 8 rows of cooling passages..



See, its tiny.. about 1 foot long, total length with tanks and everything. this is literallythe SMALLEST intercooler ive ever layed hands on..

what ya want for your PT loozer intercooler, Josh?