Engines under forced induction

[Shteifen]

ya suspension and all bushes have been upgraded.
got the 97 vr brakes, the 288m ones so they should do for now at least, can always upgrade later if i find they arent cutting it. gear box work would be on the cards too along with the rebuild.

-steve

[VR6man]

GT3082R is pretty big isnt it? i mean its not massive but its on the larger side of say the T3/T4 that comes with a kinetic kit isnt it? (i dont knwo much about different models or specs of turbos and compressors and whatnot btw)

-steve

Perfect size for a 6 cylinder around 3 litres, will boost quickly with its smaller turbine wheel and won't require a huge intercooler.
T3/T4 is a bush bearing and will generate way too much heat and is only oil cooled where the GT3082R is water and oil cooled required very little cool down time.

got the 97 vr brakes, the 288m ones so they should do for now at least, -steve

great, I'm using DBA slotted rotors with mintex pads and its made a huge difference

[Jarred]

Have a look on vortex, but i'm pretty sure GT30 is kinda the smaller side/ entry level size turbo on turbo'd vr's.

[Shteifen]

ya i thought the samllest sort of turbo i'd seen used on vr's on vortex was about a gt28. so i suppose a gt30 would be decent.
what rpm would something that size look like starting to spool and what rpm for full boost?
one thing i cant stand seeing or feeling for that matter, is puttin your foot in and gettin small power, then all of a sudden you can do nothing but wheel spin. thats useless. good to brag about maybe at dyno days, but useless for a daily.
you see it on videos on youtube all the time, they get to like ~3k rpm and hit full boost and wheel spin through 1st, 2nd and 3rd. useless. to me anyway.

the brakes on my vr feel SO much better than those of the 2.0 mk3 that i had before hand. massive improvement. may upgrade pads and rotors if i need to but these stop me ok at the moment

-steve

[mk1turbo79]

A gt3082R with a 1.06 exhaust housing on a 2.9L was starting at 2.8k an full boost by 4k. With a .82 exhaust housing it is about 400rpm earlier. The other option is a 0.63 exhaust but is getting a bit small and may choke up at high rpm.

[DubSteve]

Kinetic wont deal direct with people here cause our ecu's are different and they will not deal with people here on an individual basis . I'll have an Australian spec ecu available shortly . The stage 1 kits here will be approx $4500 with the current exchange rate .

Can you please elaborate on this?

What kind of turbo kit is it and what does it consist of?

[POLARBEAR666]

One point to consider is that turbo cars generally produce far more torque down low than N/A cars of similar capacity.

Therefore they don't have to rev as much and this places a lot less stress on the engine components in the heads. Revving high wears your heads out much faster than 100,000 of low rev action. The springs will be thrashed after 100,000 if they are revving higher all the time to get moving.

Most turbo cars also have a stronger piston/rod combination and usually better head studs as well. This means they won't be under much stress.

The question of longevity for turbo cars is tuning and boost. At a certain ratio of boost turbo engines longevity goes down a lot. Eg twice factory amount on subaru's and you have to start rebuilding the motor for head gaskets every 30k as a precaution so they don't pop.

A turbo engine is like an 80kg guy who does weights lifting 100kg vs an 80kg guy who does no exercise lifting 50kg. The guy doing 100kg will probably still do more exercise than the unfit guy (N/A). Like the turbo diesel toyota hilux's that get more than 500,000k's on their first motor before a rebuild. I know this as I used to work for toyota australia.

[Shteifen]

Seems to make sense to me.

How strong does a piston rod combo really need to be to deal with low to medium levels of boost? thoughts?
on a vr6, on vortex obviously alot of people are running vr6t's and sc's on stock blocks, and they seem to go just fine.
obviously thats not built for forced induction, but does an engine really need forged everything to be built for forced induction?

-steve

[jayjay]

forged internal components will be under the same stress as stock interals however due to different piston design - ie surface area shape and material, they will have a higher maximum allowable stress, and hopefully will not succumb to yielding from heat and the higher force generated from boost.

[Shteifen]

so for around stage 2ish, like around maybe 250-280whp (no i cant be bothered workin out what that'd be in kW), would forged rods and pistons be justified? or a little over the top for a fast street car?

-steve

[Mrk_Mickey]

I'm not actually sure about this so it'd be nice to get an answer...

I was always under the impression that forged internals were for cars making respectable power. That is, cars that aren't just a stage 1 bolt on turbo kit and exhaust. I'm thinking more a stage 2 with decent mods or a basic stage 3...

can someone confirm?

[Shteifen]

thats was i was thinkin too man
dont see the point in gettin forged super strong internals for making stupid power in a front wheel drive car anyway. 4motion on the other hand, hell yeah, go all out and make as much power as you want!
-steve

[DubSteve]

so for around stage 2ish, like around maybe 250-280whp (no i cant be bothered workin out what that'd be in kW), would forged rods and pistons be justified? or a little over the top for a fast street car?

-steve

What for I'm looking at a kinetics kit at the moment that is with a T3/T4 turbo looking at around 300whp without a front mount.

And all that is, is the bolt on kit.

[Jarred]

heaps of guys on vortex run big numbers with standard bottom ends.

I've heard things like 400HP, but not 100% sure. .. Anyone have some links??s

[Shteifen]

ya they run real big numbers over there. i was just wonderin if there is any proven way to make your bottom end stronger other than doing a rebuild, cos i already plan on that.

are there any sorts of bearings that would be more suited for forced induction?
any sorts of oils?
valves? (other than just big ones, i mean the metals they are made out of)
is it a bad idea to reuse on rods? i know they wouldnt be as strong as forged ones (actually i cant remember which parts of a vr bottom end is already forged, though im pretty sure something down there is. maybe the crank or something, i forget)

-steve