Anyone Had Stalling Issues Running A 3" Intake On A 4" Turbo?

[DaveO74]

Thanks mate,

I'll check if mine is 3 or 4" as well (can't remember)

[Harey]

ID Tag says this:

EI 0149J

GT2835-56T

700177-3

[Harey]

Cut and pasted from another disco post:

700177-2 ... GT2835 52T with 84T turbine

700177-3 ... GT2835 56T with 84T turbine

700177-4 ... GT2835 56T with 90T turbine

So is the -3 the one to get for a stock RB25? What ID's does everyone else have?

[tridentt150v]

I run the 4" Garrett 3076 with 3" reducer and have no issues. Now I know that the specs for the HKS are different and could do different things, but all things considered, I reckon you'll be fine with it.

[Harey]

I run the 4" Garrett 3076 with 3" reducer and have no issues. Now I know that the specs for the HKS are different and could do different things, but all things considered, I reckon you'll be fine with it.

Great to hear mate thanks for the first hand experience! So you run the reducer straight off the turbo then a 3" 45/90 deg bend to the afm?

[Fat_Tony]

Mine came with a reducer to the Intake pipe. I'm pretty sure its 4" on the turbo, definitely bigger than the intake pipe. I'll measure it on the weekend.

See thats the thing all the people on here that I have spoken to with the Pro S (joeyjoejoe, 75coupe and others) all have the 3" intake.

Are you sure the Pro S kits came with a 4" to 3" reducer at the turbo? As far as I know the Pro S kits have been discontinued and only the KAI is still made.

[Harey]

That would be great Fat_Tony, that would put the issue to rest.

Out of interest what results did you get from yours? Do you have a dyno sheet in the dyno thread?

[Fat_Tony]

That would be great Fat_Tony, that would put the issue to rest.

Out of interest what results did you get from yours? Do you have a dyno sheet in the dyno thread?

No sheet. 345rwhp on 18psi. I think its a little low but my engine old and tired. Almost dead.

[DaveO74]

I have 700177-3 ... GT2835 56T with 84T turbine as well harey, 4" at turbo and 3" intake with black reducer. I think we have identical huffers but your dump is a little different by memory??

Im gonna run the 3" intake, my tuner (Unigroup) reckons its not a problem

[Harey]

I have 700177-3 ... GT2835 56T with 84T turbine as well harey, 4" at turbo and 3" intake with black reducer. I think we have identical huffers but your dump is a little different by memory??

Im gonna run the 3" intake, my tuner (Unigroup) reckons its not a problem

Great to hear! My dump has been modified as the angle at the front pipe is different and there are lots of extra welds. My tuner is going to modify it.

[DaveO74]

Cool, can you hurry up though I want to see what it puts out....hahahaha (just jokes)

Mine is a long way off being bolted on and I'm just soooooooooo curious.

[discopotato03]

Don't trust my fallable memory because it could well be 100 and 80mm .

All GT2835 Pro S turbos (AFAIK) used the -3 cartridge meaning the cropped 84 trim GT30 turbine and the 56 trim 71.1mm GT compressor wheel . I think other HKS variants used smaller trim compressors or the 90 trim turbine but not the Pro S one .

A .

[DaveO74]

Hey disco it appears that although Harey and I have the same turbo we have slightly different dump pipes.

Do you know anything regarding the hks dumps, as in was there a revised edition with a slight design change?

[badhairdave]

No issue stepping up the intake as long as it has a reasonable length intake pipe.

I have installed one of the early proS kits on a mates rb25 with the supplied 3-4 inch adapter and 3inch intake pipe and there was no stalling issue there. Stock bov.

I ran my 3071 rb25 with a 3-4 inch step and no bov and it never stalled.

I ran my old hks t300s low mount kit rb25 with a 3-4 inch step and a very tight type r bov that didn't open unless there was 15psi+ behind it and it never stalled.

My old gcg highflow on a high mount manifold with very short intake pipe, 3-2.5 step down and no bov stalled like a mofo.