Turbo help

[llukejp 10]

Hi guys iv searched and searched to try and find out as much info on turbos as poss and all have is a slightly better understanding and a headache. I am running a vr6 turbo set up at the mo which I have only just finished a couple of months ago. Now I have it running and set up I'm want to start upgrading stuff and the first thing on my list is the turbo, I am running a cheap Ebay turbo gt35 copy at the mo ( I know they are poop) but like I said it is a set up/ test build if you would. Anyway I have been offered a holset hx52 11cm turbo that is in good condition and ready to go but I am currect in thinking its to big for the engine and boost would kick in to late in the Rev range. I'm so confused with exhaust housing sizes as again if I'm right that's the part that contradicts when the boost kicks in. Any help would be awesome.

Cheers luke

[llukejp 10]

Oh yeh I'm currently running 300bhp and I want to hit around 400bhp mark if that helps

[VEEDUBBED 0]

I've got a twin-scroll kkk.28 for sale that would be more or less the equivalent of a Garrett gt40, you could always use the turbine housing off a Bmw 735 turbo (originally equipped with a kkk27 turbo) that would spool reasonably quickly.

The Holset offered sounds huge, a hx35 is already quite big also, i find that its not easy to understand the A/R's of the Holset range of turbos either, more simple using Garrett, .48, .63 etc.

The ideal situation would be like I've done and many others, fit a small nitrous set up to kill the lag, you'll only need it for a small amount of time when boosting, various benefits include cooler inlet temps, and more power low down.

Also playing around with the cam timing would help the engine to boost earlier but on the vr it's not as simple to do as, for example a cossy engine. Also tweaking the ecu (programmable?) def. helps, advancing the timing off boost, bigger diameter exhaust down pipe etc, ball bearing cartridge'd turbo, modified exhaust wheel such as a 4/5 degree cut back on the wheel's blades.

I personally think that a gt series Garrett would do the job or if you can afford, the Borg-Warner range of twins-scroll EF series turbos, night and day difference when compared to other turbos but at a price.. and to reap the full benefits of said turbo you'll also have to add on a twin-scroll manifold to match..

[llukejp 10]

Spot on bud thanks for the tip the hole thing has been a home build and on the job learning so any info is good info.