GDBSTi

Fitted the HKS GT-Type Top Mounted intercooler on my STi 8 (no cats, HKS s35i's Iridium plugs, Ecutek re-map, 255L/hr fuel pump) yesterday.

This top mount is seriously heavy and BIG. I reckon it is 2 x bigger than the standard STi TM. It is very well made and bolts on in 10 minutes. HKS claim its good for 500bhp. Much better than the work of fitting a FMIC.

It seems the VF35 is much more willing to boost higher now, as much as 1.5bar and hold 1.4 bar till 6000rpm !!!with the same duty cycles as per 1.35bar and 1.25 bar at 6000rpm with the standard intercooler. I presume this is a similar effect to overboosting when the ambient temperatures get colder?

Perhaps someone has an explaination?

Does this mean I can run the VF35 at higher boost since the intercooler is more efficient or is the limiting factor more that the VF35 becomes inefficient above a certain boost?

Ted Ed

GDBSTi

Where did you buy it from and how much.. any pictures.

Thanks

Simon

dowser

Increase in boost is bacause your new i/c is not such a big restriction to airflow.

I would recommend caution - get the car checked out with DD if not done already. Was you remap done to cater for 1,4 bar at 6k - how much boost was it holding before? If not catered for, you'll be off the load scale and into dangerous territory, even assuming intake temps are OK.

As for what is safe boost wrt the new i/c - I'd recommend fitting at least a temp probe in the throttle body (better one at turbo outlet too). With a tmic, what may be good on a single power run will cause intake temp problems after extended power use. The engine itself radiates a large amount of heat at WOT, which the tmic gratefully receives.

I should add that I also run a tmic

Richard
PS: get the car checked out ASAP - I seriously doubt it is safe currently

carlos_hiraoka

got any pics of this HKS TMIC ?

Carlos H.

GDBSTi

I can take some pictures with my digital , but not sure how to put them onto the forum? I can definitely email to individuals.

As for the 1.4 bar at 6000rpm. I was running 97RON fuel + 2 x bottles of NF Race Formula. Knock Link dead quiet and DD showed 4+ degrees of timing right through rev range. The scaling on my Ecutek map is adjusted for higher loads than 1.35 bar on a VF35 ;-). Obviously the IDC were a bit high :-( with standard injectors. Turned duty cycles down now using user tuning for the moment. I love user tuning!!


The less restriction theory makes sense I suppose though I thought the standard TMIC was pretty good.

I suppose a temp prob would give me more answers. Next task :-)

RT

How well does the HKS GT intercooler "interface" with the OEM rubber boot on the underside of the air scoop (on the bonnet)? The original intercooler's fins are slightly recessed so that the boot can fit in. Do you have to alter or remove the boot with the new IC?

Cheers.

GDBSTi

Funny you mention that as I removed the boot since it was just getting pressed flat against the HKS unit and the GT fins are a lot more vulnerable to bending than the OEM TMIC fins. The HKS GT TMIC is so close to the entrance of the scoop (0.5 -1cm) without the boot fitted that I don't think it is necessary to make up a boot. It also lines up evenly under the entrance with nether rear or front end higher or lower. It might be an idea though to make up a bigger entrance as the HKS GT TMIC is at least 10-15% bigger (Length X Breadth) than the standard TMIC. I will look into this soon.