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Mr_zero
05-19-2005, 02:46 AM
I have searched the forums. I have searched google. But I have not found the technical answer to my problem...

How does a v-mount help with cooling, power, and longevity of the engine? I know what it is supposed to do, but does anyone have numbers to prove it? Eg. temp lowers by 20F or something like that?

Also, I hear that supposedly the optimal running temp for a sr20det is between 170-180F (water temp). If this is so, why do so many drifters run v-mount setups (which @ speeds of 80mph plus, would lower this water temp well below 160)?

Like I said before, I am well aware of what it is supposed to do, but I have not yet found numbers, hp gains, technical stats etc. to prove that a v-mount actually does do what it should...

any help?....

Romeyo07
05-19-2005, 06:37 AM
from what I've seen and read, it's just not really worth the effort. I think if it ain't broke, don't fix it. Mounting your intercooler in front has worked for a bajillion people. No need to re-invent the wheel. I don't see anything wrong with v-mount, but I just hate to go through extra effort to reach the same goal.

the head
05-19-2005, 09:24 AM
v-mount will basically shorten your charge pipes and allow the radiator fresh air instead of air that has passed through and intercooler (and in my case also oil cooler) before reaching it. Also it moves the rad and IC inside the framework of the car diminishing the potential for damage to those pieces in a crash

Mr_zero
05-19-2005, 09:46 AM
Ok but in terms of cooling of the water, will the decrease in temp actually improve engine performance or life? Eg. if your engine runs at 140F because of the v-mount is that bad considering you are out of the "optimal range"?

krustindumm
05-19-2005, 10:36 AM
there is still a thermostat, which will regulate the temperature of the coolant.

Pepperoni
05-19-2005, 11:04 AM
Wow is it true "optimum" temp is up in the 170-180ºF area? Im usually at 150ºF. i dont think it really matters too much unless it's running way too cool. im in CA, using clutch fan, no fan shroud, KA radiator.. everything seems to be working just fine, engine runs strong

Mr_zero
05-19-2005, 11:47 AM
That is what is my main concern. Is it really that much worse to run cold and if so why do race cars, D1 drivers etc run a v-mount setup that will decrease temps so much? No one knows?...

the head
05-19-2005, 12:30 PM
race cars see sustained high RPM use therefore higher engine temps ergo they use a V-mount to decrease temp because thier operating temps are higher to begin with therfore needing the added cooling efficency of highpressure ducting and v mount arrangements

where did you get the info on optimum operating temps? also the t-stat will regulate temp in the engine more than coolant will.

TurDz
05-19-2005, 12:30 PM
Where did you get this info of optimal cooling temp? are there any disadvantages?

Cooling the compressed air as much as possible simply seems like the main goal, and I'd like to know if any harm can be done to the engine for having TOO cold air. I will ask my professor about this today too and post back if no one has an answer.

the head
05-19-2005, 12:34 PM
I would assume yes look at nitrous oxide technically all it does is supercool the intake charge and when you cannot add enough fuel to keep the car a stoich or close to it BOOM the shit is toasted

Angel
05-19-2005, 01:52 PM
You can cool the coolant too much, if the car runs too cool it will lead to accelerated wear on a few coponents, loss of power ( because some of the energy from cumbustion will be lost trying to bring the temp up ) and in most cases will keep the ecu thinking it is still in warm up ( if extrememly low )

So there is an ideal range let' say 170-190 more or less.

Now to TurDz- Cooling the intake charge is completely different and usually cooler is better , so long as your engine management is set up to handle it properly. In practice it is hard to get the temps to much below about 60f via normal intercooling methods. Using no2 or methanol and the like can bring it down further in some cases and there is power to be had from that alone if your ecu can make the calcs or is mapped for it... now this is also directed towards "the head" as well, a good part of the power gained from using no2 and meth is from the oxygen content in the case of nawz and the ability to run more agressive timing advance and more boost :) in the case of the meth.
Oh yeah, I know that nobody mentioned meth injection.... but I did, it's good stuff.

krustindumm
05-19-2005, 03:55 PM
Stock thermostat temperature is ideal for economy, emmisions, and longetivity. Personally, I'd keep that. I believe there is a Nismo thermostat with a slightly lower set temp.

I'll check my FSM later and see what the factory temp is, but my civic was 210*F, which should preovide a reference. Domestics (especially older domestics) tend to be around 180*F.

-Dustin

the head
05-19-2005, 03:58 PM
newer domestics are usually 210 as well

Nismo and Billion both make low temp stats for the sr

Johny5
05-19-2005, 04:08 PM
i know this thread is intentionally aimed at cooling temps so if i could share. some have seen drops as much as 7C (because no one rocks usdm shitty gauges showing F, haha) from their v-mount setups. and in an even better point of v-mount, no more longass hot and coldpipes, shorter air routes increase throttle response <3

TurDz
05-19-2005, 06:57 PM
Okay, intercooled air cannot get any cooler than atmospheric air (unless injected with nitrous).

I think it's safe to say that there isn't a temperature of air that is TOO cold...the colder the better. All it means is that the air is much more dense, therefore more power. There shouldn't be any harm to the engine either.

ghostuss
05-19-2005, 07:40 PM
But if you going at like 80mph, the air in the IC would be much cooler than the air in the atmosphere. There won't be any harm to the engine as long as the ECU is tuned for it. That's why daily driven high HP car sucks cause you have to retune every season or else it will performance like shit or at least not as good as what it tuned to be.

Angel
05-20-2005, 09:51 AM
Okay, intercooled air cannot get any cooler than atmospheric air (unless injected with nitrous).

I think it's safe to say that there isn't a temperature of air that is TOO cold...the colder the better. All it means is that the air is much more dense, therefore more power. There shouldn't be any harm to the engine either.


Unless you are using an air to water, maybe with ice or alchy. My old gsr powered civic coupe t3t4 running 26 psi would show a peak of about 65f on the haltech logs after a nine second pass and that was with just a bit of ice with plain old water in 90-110 weather. Of course air to water isn't really suitable for anything other than drag, dyno or top speed runs.

Angel
05-20-2005, 09:58 AM
But if you going at like 80mph, the air in the IC would be much cooler than the air in the atmosphere. There won't be any harm to the engine as long as the ECU is tuned for it. That's why daily driven high HP car sucks cause you have to retune every season or else it will performance like shit or at least not as good as what it tuned to be.


The air will be no cooler than ambient, it may feel cooler on your skin but it isn't. And high hp cars don't always have to be retuned if they were mapped correctly ( sometimes hard to do for all conditions ) I just spoke with an old cutomer of mine after about 3 years or so, and his 800 rwhp stock block and head supra is still running flawlessly on the original AEM map and still running 145 mph traps at full weight and a very simple and evidently reliable setup ( precision 74mm gtq turbine, greddy fmic, hks 272's, and 850 injectors )