wullysmith
New Member
.
The HOLSET Thread
- Thread starter dale_b
- Start date
thebe
Member
It was easy and cheap to make. First time making one and it hasnt failed.
KetsMcLets
New Member
Great thread! Took a while and fell asleep couple of times but great read!
Currently: forged RB25DET with original manifold and internally gated Holset HX32 from Compressor Racing. Turbo spools fast and delivers me 423bhp/506Nm @ 1.4 bar, but lots of backpressure and egt's are high. A lot to gain through better timing but no E85 readily available here.
This is my last power build in my life and I wanted to crack the 500/550bhp mark this time but I bought the wrong turbo I guess, was looking for great spool but made a rookie mistake of getting too small a turbine and sacrificed a lot of top-end..
Now I'm looking @ getting me an HE351 with a decent twinscroll manifold, big downpipe and progate instead. What ballpark bhp figures will this give me you guys reckon?
(supporting specs are EV1000's, 455lph pump, R8 coils, NZ wiring trigger kit, big IC, freddy with Q45 tb, no headwork and oem cams, Link G4+, fpr, 3" exhaust, 3" ic piping)
Currently: forged RB25DET with original manifold and internally gated Holset HX32 from Compressor Racing. Turbo spools fast and delivers me 423bhp/506Nm @ 1.4 bar, but lots of backpressure and egt's are high. A lot to gain through better timing but no E85 readily available here.
This is my last power build in my life and I wanted to crack the 500/550bhp mark this time but I bought the wrong turbo I guess, was looking for great spool but made a rookie mistake of getting too small a turbine and sacrificed a lot of top-end..
Now I'm looking @ getting me an HE351 with a decent twinscroll manifold, big downpipe and progate instead. What ballpark bhp figures will this give me you guys reckon?
(supporting specs are EV1000's, 455lph pump, R8 coils, NZ wiring trigger kit, big IC, freddy with Q45 tb, no headwork and oem cams, Link G4+, fpr, 3" exhaust, 3" ic piping)
thebe
Member
Hey!
I have rb30/25det with a he351 holset (14cm) running 553 HP at ~1,5 bar. Stock head too. You should be able to get similar or a bit higher HP figures with the 25, propably just a bit higher in the rev range (I've limited mine to 6800rpm).
I posted a bigger spec list and dyno graphs here ~2 years ago. Page 85 here
KetsMcLets
New Member
Hey! Thanks for replying! Yes I saw your post, very interesting! I compared your graph and spool isn't very different except you have 500 more cc's offcourse. The turbo I'm looking at has a 16cm turbine though, this might be a bit too laggy for me...I don't know..I'll see when I get to it I guess next year somewhere, but I'm contemplating my options. I LOVE my Holset and would love to stay with the brand :-) Right now budget is leaning towards the respray which turned into a semi-restauration..
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stevieturbo
Member
spraying from where exactly and when ?
genuine, off a daf truck, came with 21cm2 housing, i have put on an 11cm2 one from compressor racing
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stevieturbo
Member
sounds fucked then.
Presumably you've checked the obvious, impeller wheel/shaft for excess movement etc ?
Ensure oil return is good ?
Presumably you've checked the obvious, impeller wheel/shaft for excess movement etc ?
Ensure oil return is good ?
Yeah all that is good. I've been told it could be seal? I'm going to see if I can get it repaired for cheap
oil return is god, do i need to fit a restrictor, been told it could stop leak
what size do i need?
Im unning 14cm on a 1jz vvti seems to pretty laggy. Not 100% sure if the setup is bad or an issue somewhere.
1jzgte vvti
walton manifold
Link Ecu
Injectors 630cc
50 Turbosmart gate
3 inch downpipe
HTX4064b2 single scroll 14cm (hx40 holset equivalent dual ceramic ball bearings)
Compressor side:
1jzgte vvti
walton manifold
Link Ecu
Injectors 630cc
50 Turbosmart gate
3 inch downpipe
HTX4064b2 single scroll 14cm (hx40 holset equivalent dual ceramic ball bearings)
Compressor side:
- Compressor wheel: in-house made, reinforced 64/79mm 10+0 blades machined from the solid aluminium;
- Intake: 101mm (4");
- Air outlet: 63mm (2.5");
- Bearings: dual ceramic ball bearings;
- Cooling: water cooling with 2 x M14x1.5 ports;
- Lubrication: AN4 oil inlet with integrated oil restrictor;
- Housing: single scroll, 14cm2 / AR: 0.82;
- Turbine wheel: custom design 76/64mm 10 blades
- Flange: T3 single scroll;
- Exhaust connection: 3" V-band clamp;
Hey folks,
I just wanted to say thankyou to the many people who have contributed to this thread which is frankly a font of Holset knowledge unsurpassed anywhere else. You've built a lot of awesome cars over the years.
Hoping to add to that list myself, I don't have deep enough pockets or the correct drivetrain setup for drifting, but I thought I'd ask here because of all the knowledgable people.
So, the plan. It's a Volvo T5, specifically the 2.5 found in the Focus ST as well as various Volvo/Ford models. Will be forged, likely with cams too, and all the usual supporting bits. Stock compression ratio, so 9.0:1, and it has dual inlet/exhaust VVT on Tesco's finest pump fuel. Will be running a maxxecu with EGT and likely backpressure sensor too.
Turbo of choice is a HY35W, brand new, 9cm2 housing. Single scroll. Will be fitted to a tubular manifold, and likely either sized up to a 4 inch downpipe or do as others have done in the past and cut the back of the turbo off to go straight to 4 inch. I'm undecided on the exhaust, it's currently got a 3 inch Milltek which sounds great and isn't too loud so I can do trackdays at Thruxton etc quite easily. I suspect eventually it'll have a 4 inch system custom made if one can be done quiet enough.
My main questions;
1. Holsets are well known for having shite internal wastegates. This seems to be primarily aimed at the twin scroll turbine housings though, where the wastegate only affects one scroll and therefore only half the flow. With this being a single scroll, is it possible that the wastegate will be okay? I am looking to cap torque at 400lbft, so whilst I'll still be at 18-19psi in the midrange I will be venting some off, although towards redline I'm sure it'll be up in the 20s.
2. I already know that with a 2.5 litre with VVT and a 9.0:1 CR it's going to spool well, I'd like it to be by 3000rpm, but what do we think about its chances of hitting 500 peak? I don't really care - the idea is to make 400lbft (about the maximum I can transmit to the road) across as wide a rev range as possible, so making a peak power number is secondary, but I wonder if the backpressure of using it with a 2.5 litre and the 9.0:1 compression ratio will scupper me. I know there's that saab that made 488 wheel with a 2.8 litre engine, but they were running E85, which is scarce here. I guess there is a positive point in that being a single scroll housing it'd flow a little better than the usual twin scrolls.
I just wanted to say thankyou to the many people who have contributed to this thread which is frankly a font of Holset knowledge unsurpassed anywhere else. You've built a lot of awesome cars over the years.
Hoping to add to that list myself, I don't have deep enough pockets or the correct drivetrain setup for drifting, but I thought I'd ask here because of all the knowledgable people.
So, the plan. It's a Volvo T5, specifically the 2.5 found in the Focus ST as well as various Volvo/Ford models. Will be forged, likely with cams too, and all the usual supporting bits. Stock compression ratio, so 9.0:1, and it has dual inlet/exhaust VVT on Tesco's finest pump fuel. Will be running a maxxecu with EGT and likely backpressure sensor too.
Turbo of choice is a HY35W, brand new, 9cm2 housing. Single scroll. Will be fitted to a tubular manifold, and likely either sized up to a 4 inch downpipe or do as others have done in the past and cut the back of the turbo off to go straight to 4 inch. I'm undecided on the exhaust, it's currently got a 3 inch Milltek which sounds great and isn't too loud so I can do trackdays at Thruxton etc quite easily. I suspect eventually it'll have a 4 inch system custom made if one can be done quiet enough.
My main questions;
1. Holsets are well known for having shite internal wastegates. This seems to be primarily aimed at the twin scroll turbine housings though, where the wastegate only affects one scroll and therefore only half the flow. With this being a single scroll, is it possible that the wastegate will be okay? I am looking to cap torque at 400lbft, so whilst I'll still be at 18-19psi in the midrange I will be venting some off, although towards redline I'm sure it'll be up in the 20s.
2. I already know that with a 2.5 litre with VVT and a 9.0:1 CR it's going to spool well, I'd like it to be by 3000rpm, but what do we think about its chances of hitting 500 peak? I don't really care - the idea is to make 400lbft (about the maximum I can transmit to the road) across as wide a rev range as possible, so making a peak power number is secondary, but I wonder if the backpressure of using it with a 2.5 litre and the 9.0:1 compression ratio will scupper me. I know there's that saab that made 488 wheel with a 2.8 litre engine, but they were running E85, which is scarce here. I guess there is a positive point in that being a single scroll housing it'd flow a little better than the usual twin scrolls.