Jump to content
SAU Community

Recommended Posts

Recently I performed some intake temperature tests. They are not dead acurate but are atleast an indication of when heat soak is affecting your engine. I used some digital thremometers from jaycar for the tests.

The car: 1993 R33 GTSt, 3" turbo back exhaust, 8psi (stock) boost, stock intercooler, pod filter with cold air partition (95deg neoprene heat shield).

Ambient temperature: 17degC

1st Test: Cruising at 110km/h

Pod = 15deg

AFM = 15deg

Engine Bay = 35deg

2nd Test: Stuck in traffic (45km/h max.) (heat soak had set in)

Pod = 35deg

AFM = 37deg

Engine Bay = 55deg

3rd Test: On boost hill climb and high speeds

Pod = 14deg

AFM = 12deg

Engine Bay = 33deg

4th Test: Heat Soak

After pulling up at a set of lights from cruising at 110km/h, it took 3 minutes to reach full heat soak as shown in the 2nd test. It took 7 minutes of driving at 110km/h again to fully get rid of it.....

5th Test: After idle for 3 mins

Pod = 40deg

AFM = 43deg

Engine Bay = 60deg

Link to comment
https://www.sau.com.au/forums/topic/21359-r33-gtst-intake-temperature-tests/
Share on other sites

pod filter with cold air partition (95deg neoprene heat shield).

rb25 - do u have a cold air intake?? e.g. a tube rigged from somewhere front of your car to feed your partition steady supply of cold air? Of course, not much use at idle.

*Very* interesting results, about time somebody got scientific on this :P

Those that take their skyline to the strip should take note. Obviously sitting there idling as you wait to get your run (can be 20mins), gradually moving forward - its just like traffic unfortunately. Even if u regularly turn your engine on and off heat soak is going to set in and its going to effect your times.

A suggestion: Can u at all do plenum temperatures? Obviously you've got some good before intake results, but the most important thing is the actual temps going into your engine..

Interesting results...

Now all u need to do is *borrow* someones carbon fibre bonnet with the vents in it and see how much of a difference it makes (obviously weather and traffic conditions would be hard to keep accurate).

Interesting. The people driving around with pod filters but without partitions should take note of the air temps they are sucking in.

What thermometer model did you use?

I tried to buy thermometers from Jaycar 2 weeks ago to perform similar testing with my own partition (http://www.endusk.com/skyline/caip/caip.html) but the dumbasses couldn't find where in the shop they put them.....

When I get some I will add some notes on the temp differences between using just neoprene and using aluminium + neoprene stuff + sealing rubbers.

I forgot to mention that without a duct forcing air into the partitioned area the heatsoak reduced at 60km/h and above, even in traffic.

predator666: I dont have a duct rigged up to it at the moment. I will do some plenum temps very soon (end of this week/early next week)

Sil8ty: I got the heatshield from Century Foam and Rubber. It's about 8mm thick, sort of like neoprene and has a reflective foil on one side. My partition cost 2 hours of time and 4 dollars.

kjb_r33: I've been informed that the clutch fan on the engine from the factory is excellent in its efficiency and i think that at high engine speeds it pulls alot more fresh air int the engine bay thus making it cooler.

sewid: boxhead has a similar partition (made from metal) and it gets red hot. Metal partitions in my opinion suffer from heat soak and would lengthen the times to get the intake temps down.

I've posted a pic of my setup below. I know its rough, but it seals to the bonnet and the top of the wheel arch and right up to the back of the headlight and it works really well.

Originally posted by rb25

sewid: boxhead has a similar partition (made from metal) and it gets red hot. Metal partitions in my opinion suffer from heat soak and would lengthen the times to get the intake temps down.

I have thought about that as well. Now the aluminium is insulated with foam it gets warm but never hot/red hot/too hot to touch.

To solve the problem of getting the heat out of the aluminium i was thinking of thermal epoxying on some aluminium heatsinks on the cold side.

I dont know if this would worsen the problem of heatsoak however in the long term or increase the effective heatsoak time to beyond average lenght of time spent stopped thereby negating it.... Only way to find out is to experiment.

Or could just remove the headlight and poke the pod out the front :D

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Yup. You can get creative and make a sort of "bracket" with cable ties. Put 2 around the sender with a third passing underneath them strapped down against the sender. Then that third one is able to be passed through some hole at right angles to the orientation of the sender. Or some variation on the theme. Yes.... ummm, with caveats? I mean, the sender is BSP and you would likely have AN stuff on the hose, so yes, there would be the adapter you mention. But the block end will either be 1/8 NPT if that thread is still OK in there, or you can drill and tap it out to 1/4 BSP or NPT and use appropriate adapter there. As it stands, your mention of 1/8 BSPT male seems... wrong for the 1/8 NPT female it has to go into. The hose will be better, because even with the bush, the mass of the sender will be "hanging" off a hard threaded connection and will add some stress/strain to that. It might fail in the future. The hose eliminates almost all such risk - but adds in several more threaded connections to leak from! It really should be tapered, but it looks very long in that photo with no taper visible. If you have it in hand you should be able to see if it tapered or not. There technically is no possibility of a mechanical seal with a parallel male in a parallel female, so it is hard to believe that it is parallel male, but weirder things have happened. Maybe it's meant to seat on some surface when screwed in on the original installation? Anyway, at that thread size, parallel in parallel, with tape and goop, will seal just fine.
    • How do you propose I cable tie this: To something securely? Is it really just a case of finding a couple of holes and ziptying it there so it never goes flying or starts dangling around, more or less? Then run a 1/8 BSP Female to [hose adapter of choice?/AN?] and then the opposing fitting at the bush-into-oil-block end? being the hose-into-realistically likely a 1/8 BSPT male) Is this going to provide any real benefit over using a stainless/steel 1/4 to 1/8 BSPT reducing bush? I am making the assumption the OEM sender is BSPT not BSPP/BSP
    • I fashioned a ramp out of a couple of pieces of 140x35 lumber, to get the bumper up slightly, and then one of these is what I use
    • I wouldn't worry about dissimilar metal corrosion, should you just buy/make a steel replacement. There will be thread tape and sealant compound between the metals. The few little spots where they touch each other will be deep inside the joint, unable to get wet. And the alloy block is much much larger than a small steel fitting, so there is plenty of "sacrificial" capacity there. Any bush you put in there will be dissimilar anyway. Either steel or brass. Maybe stainless. All of them are different to the other parts in the chain. But what I said above still applies.
    • You are all good then, I didn't realise the port was in a part you can (have!) remove. Just pull the broken part out, clean it and the threads should be fine. Yes, the whole point about remote mounting is it takes almost all of the vibration out via the flexible hose. You just need a convenient chassis point and a cable tie or 3.
×
×
  • Create New...