HKS Intercoolers

[madman]

I can't get a definitive opinion on this subject, so want some comments.

Got R33 GTR Vspec, HKS Cams,HKS pulleys, HKS exhaust, HKS super power flows, Nismo clutch, engine oil cooler etc.. etc.. and it runs quite well.

But obviously not fast enough. Certain people have suggested that fitting an HKS intercooler (the cheaper one, not the expensive GT thing) will lower the charge temp sufficiently to add between 20 and 25bhp and enable me to the up the boost from 1 bar to 1.1 bar. (adding another 15-20bhp) as the turbo will be suffering slightly less thermal stress.

The people who service my car say NO! Not if you want to keep the turbos. But I have heard a lot of others saying YES.

Now I am sure i have read of other users running ceramic turbos over 1 bar. And I live in the UK and a hot day is 20 degrees C out here! Not like hot Australia...

[Gtr2.7L]

You could possibly post 20-25hp out of a 700-800HP engine....but you won't post those numbers (20-25 gain) on stock turbines....probably more like 4-6. The stock intercooler is VERY good up to 600-650 or so. 1200 bucks is halfway through an HKS turbine upgrade kit....might as well go with the 2530's and put your other upgrades to use.

[madman]

The problem with putting new turbos on though is the lag. I really dont want extra lag.

If upgrading to say 600-700bhp then the lag would not matter too much. But say i now have 425bhp, and i change the turbos, run a bit more boost and get 500bhp with HKS turbos, the lag will affect my performance to the point that my 100-150mph time may be much quicker, but in normal driving my 0-100 will hardly change. And my reaction time when i slam my foot to the floor will drop significantly.

And replacing the turbos is a big spend for a very small amount of power. (unless i want to change my injectors, head gasket, etc.. etc..)

I guess what I want is increased performance as opposed to absolute power.

[SkylineUSA]

N2O

With a small shot and new turbos, you will be in a rocket.

[Gtr2.7L]

The increase in lag with 2530's is hardly noticeable. If you go with the 2510's, it actually decreases. I'm just letting you know that unless you're engine is capable of high amounts of horsepower, you're not going to get much of anything out of a new intercooler.

[madman]

whats the difference between a 2510 and a 30?

I have sort of considered changing the internals of the stock turbos to a steel/nickel composite. I am told that lag then is hardly noticeable compared with ceramic. It will cost me about $1100

I have seen reports on bhp figures with steel internals and have seen figures creeping towards 500bhp with them (and all i would need to buy additionally is new injectors which are cheap)

What surprised me though, is that the cars still werent running above 1.25 bar.

I think i messed up when they recently rebuilt my engine. They said "do you want us to fit a steel head gasket". I said "I'll never need one, I don't need more power" duh!

I wonder how many BHP it takes to blow out the standard one. I guess I'll soon find out ....

[R33]

Madman, if your ambient temp is 20 degrees C and you are running stock turbos, forget about the HKS intercooler! The larger HKS IC would just make the charge pressure drop and along with that , your horse power.
I was running 1.02 bar on my stock turbos before. But ambient temp here is around 35 C. So, with a view towards high horses later, I put in the HKS GT IC. Absolutely no power gain! But of course the GT IC is needed for my current 2540s.
I am always against altering the stock turbos as I fear it won't be reliable. If you just change the impellers to steel, that sounds okay to me and what that does is, it enables youn to run more boost than the stock turbos. But if you start altering the turbo housing in the process, that would result in a thinner housing and in my climate, that might induce crack in the housing. If you want better performance up to between 450-500 horses without any substantial increase in lag, I would recommend the 2510 and the metal head gasket. With all your current mods, especially the cams and pulley, the 2510 would really make full use of them.
That's my 2 cents worth.

[meggala]

I've been in a gtr with 2510's if you really want respones that is the way btw with engine work this car ran mid 11'second 1/4 miles to do it the other thing to consider in the n1 replacemant turbo's they are quite good as well.
meggala

[Gtr2.7L]

2510's and 30's only differ in size and flow...which leads to output
(the following are "recommended by HKS"...but have and often are pushed higher)
2510's are good for 280PS each (total 560)
2530's are good for 320PS each (total 640)

The 2510's are the same as stock except Ball bearing, steel compressor wheel....etc. I believe the housing is the same as well...Garrett and HKS are comonikered somehow. The 2510's designed for same max output but for high stress circuit running.

The stock head is good until 600 or so....but even on a completely stock car, they only last around 100k kilometers or so.

I sympathise with the low boost high output gang
My last dyno showed 42(x) at the wheels at 1.1 bar.

A buddy of mine took his GTR camping and bottomed out the front....right into a big a** rock. Cracked his bonnet and stock intercooler. Replaced the intercooler with a Greddy 3-Core (which was only two hundred more than stock). Of course he went running down to the dyno, only to post 3ps more (he's running around 500 to the wheels). He was a tad dissapointed....but figured at least it's there when he decided to go for the T88
I think the Intercooler inadequacy is one of the classic GTR myths.

[madman]

Firstly i think UK average temp is probably closer to 7 degrees or something rediculously low. Always good cool damp air (Bad to live in, but superb for a turbo).

When I last spent money (Downpipes, cams, pulleys, chip, nismo clutch cover), some of the competitors said.. "Don't do that, but an HKS intercooler + hardpipe kit and the downpipes".. The company who fit the stuff (Middlehursts if youve heard of them) said that they wouldnt go with the intercooler thing..

The chap who quoted on the turbos was offering to change the impellors to steel/nickel and fit 360 degree thrust bearings.

If i could run at 1.2 - 1.3 bar with them, then that wouldnt be far from 500bhp (to my reckoning).. Again providing my head gasket could stay in place and at a very low price without sacrificing reliability..

[madman]

If the 2510's are similar to stock then having mine rebuilt to similar spec should be as good. (steel imellors and 360 deg thrust bearings)

All I am after is the magic 500bhp figure..

So how much boost would you say is the limit of 2510's (or stock with steel innards) with my car. I have seen figures of 475-485bhp. But only running at 1.25bar. I can therefore only assume that there is some reason that this person didnt push more boost through.

If necessary, i guess I dont mind replacing the head gasket ...

Finally as you seem in the know. What exactly are the standard turbos. The sales brouchure says Hybrid T3/T25. Which is suitably vague.