EK20renn

okay, so i have a good understanding of how turbos and intercoolers work, but here's my question:

at low psi - let's say no higher than 6 psi - is an intercooler or blow off valve really necessary?

i am piecing together a turbo kit for my b16, looking for around 200-220 whp. this seems relatively attainable with a t28 or t3 super 60 turbo at 6psi. boost will be properly controlled with a tial wastegate, and the car will be properly tuned.

would i really gain that much from having an intercooler, and would a blow off valve really be necessary? i'm thinking the IAT's wouldn't be that high at 6 psi, and the pressure wouldn't be enough to kill the turbo especially if it's a ball bearing t28.

i have no desire to boost any more than 6 psi, i just want a little more midrange torque. if there's no great necessity to have an intercooler or bov at 6 psi, i'd rather not spend the time and effort.

justYncredible

iTrader: (1)

Then I guess you don't want to go turbo

How is the turbo going to cooled?
How will the intake pressure be released?

EK20renn

all intercoolers do is cool the intake air after it exits the turbo... not the turbo itself.

at 6 psi will the turbo get hot enough to significantly raise intake IATs?

the intake pressure will obviously go back into the compressor but at only 6 psi i am unsure if this will damage the turbo... multiple factory cars came without any kind of blow off valve or bypass valve and run without issue. multiple factory cars also came without intercoolers and run fine too.

Khnemu

iTrader: (1)

lol

EK20renn

sick post brah


guess i'll wait for people who actually understand how turbos work to post.

grindpunk16

if you are worried about the sound of the bov recirculate the pressure back through the intake and will cut down the sound pretty nicely..... most cars that dont have a bov dont have a traditional bov, where it is mounted on the actual turbo itself. look at the borgwarner efr turbos

Ash J. Williams

There are OEM turbo systems on cars of the past and today that don't use a blow off valve nor an intercooler. My old Datsun had such a system.

grumblemarc

iTrader: (4)

You keep saying "many factory cars" but none of them were Hondas. Stop making that comparison.

Ash J. Williams

Incidentally, if you do say a water or alcohol injection, an intercooler isn't needed at all.

doood

iTrader: (1)

the old basic greddy kits didnt include intercoolers or bov's. people ran those with no issues on very low boost.

EK20renn

what would it matter?

EK20renn

i guess i'd basically be building one of those.

not using an intercooler or blow off valve cuts my cost down by almost half and really simplifies the work i have to do.

i'm more worried about not using an intercooler, the worst that could happen not using a blow off valve is i'd have to buy a new turbo and then a blow off valve. used t28's aren't that expensive. i really don't think 6 psi would snap compressor blades or something like that and ruin my motor.

grumblemarc

iTrader: (4)

You're right Forgot all about it.
Then why the need for the comparison? If it didn't matter.
Why do people post asking for help when they are dead set on doing whatever it is they're going to do anyway?
You got your answer from Dood.

EK20renn

do people not ever have technical discussion on hondatech?

a turbocharged piston engine is a turbocharged piston engine.

not using a bov and/or intercooler on a datsun is no different than not using the same on a honda.

i'm not dead set on doing it, nor have i gotten my answer.

tepid1

They are just being retards because they don't know themselves....

It can be done and has been done successfully. Even recently.

In most cases you will need to spray something into the charged air. IE: fuel, nitrous, etc....

Ethanol is gonna have to be run though. Gas creates too much heat.

TheShodan

iTrader: (14)

Umm. wrong on both counts on that one. Most of the bypass or diverter valves are recirculated so you don't here them. And yes, though small and hidden (possibly side mount intercoolers, yes, they have them.

You need both for longevity, regardless of whether or not it is just 6 psi.

I've owned everything from a '83 Turbo Datsun 280ZX to a '90 Eagle Talon, to a 2006 Turbo mini.. ALL have BOVs, ALL have intercoolers from the factory..

No bov or diverter valve means you will cause the turbo to revert and damage it, no intercooler means higher IATs.

Attempt at your own risk to "save cost".

Ash J. Williams

I hate to contradict you man, but the Zcar didn't have a blow off valve and an intercooler. It did have a pop off valve.

EK20renn

obviously most, if not all, newer cars have recirculated valves and most have hidden intercoolers. i'm not that stupid.

this is good reading with regards to not using a blow off valve. it actually mentions the Z.
http://www.rx7club.com/single-turbo-...-valve-884695/

cost isn't really the main issue, simplicity for a low boost setup is. i may try a simple setup like this out of curiosity and if my IATs are too high while tuning it and i'm getting bad compressor surge, buy an intercooler and blowoff valve.

i'd like to hear about the setups that have been successful with it. although ethanol or any injection is not an option for me, unfortunately.

wantboost

iTrader: (2)

The problem you'll have with no blow off valve is compressor surge which will eventually kill a turbo's thrust bearing.

No intercooler means elevated intake charge temps which means decreased performance and fuel milage as well as an increase in the likely hood of detonation.

Even the cheapest of eBay intercoolers and blow off valves is better than not having one

Let's be realistic for a moment lol

LightningTeg

You can get both for less then $100 on ebay that will be fine for what you want despite their cheapness.

Ash J. Williams

Bought a kompact blow off valve from turbosmart for less than 100 and bought an srt4 intercooler for 50.

wantboost

iTrader: (2)

I even have quality valves and intercoolers I'll sell you for a stupid good price. I just don't want to see you damage your turbo and potentially your motor because of an improper setup

EK20renn

i don't want a cheap BOV that will stick open or cause me other problems. multiple people in that thread on rx7club have run no BOV for 20k+ miles with no problems. no reason that shouldn't hold true here, especially at 6 psi.

as far as intercoolers, people on other forums are saying my IATs will only be ~100F greater than ambient at 6 psi which is less than some have seen even with DSM side mounts at higher boost. obviously the tuning would be very conservative.

TheShodan

iTrader: (14)

Actually people didn't. That was the only way at the time that they were able to sell a kit in California legally at the time. It was up to the consumer to purchase intercooler and BOV. Now for those the didn't run an intercooler, the blue box at the time ran 5 psi for the 18G (41lbs/min) because IATs were high enough to cause an alarm. but even shops that sold the kit said that SOME BOV was a MUST, and should be used with the kit... (God, was 1997 that long ago for the GReddy kit? Wow.. )

TheShodan

iTrader: (14)

Intercooler was hidden on the side mount. The "pop off valve" was the same as a BOV. I owned it from my step-father in 1990.

The 1981 model did not run an intercooler for a brief period in the US market, using a Garrett TB05 turbo unit. (I remember taking that apart for a science project when my uncle destroyed one back in the day). That issue was remedied with the Borg-Warner turbo unit in 1982-1983, and a side mount intercooler was used. Nissan engineers kept wondering why they had to keep power down with timing on the L-series motors. The first thing to change was the intercooler.

Yes, you're right in 1981, they did not use an intercooler. But like I'm saying now, even the engineers then agreed; its best to run some type of heat exchanger to keep the car alive and make power.

I think that's what we're all trying to say here. So we can split hairs from the 1980s if we want, but the point is, its not a good idea to run one... Even the OEM can be wrong once in a while.