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HT18S-2S turbo on SR20
Posted: Fri Aug 19, 2011 9:57 pm
by Riekert
So i bought this turbo... not i need to know if it'll be suitable for the SX
50mm intake and a 58mm exhaust.... said to be rated till 350bhp
came off a series 4 rx7
any infi will be awesome,
@ Enzio - see u are running something simmilar??
Re: HT18S-2S turbo on SR20
Posted: Sun Aug 21, 2011 5:47 pm
by BigKriss
R, anything off a rotary will have a much too large A.R turbine housing to be of much good I think..
Re: HT18S-2S turbo on SR20
Posted: Mon Aug 22, 2011 8:30 am
by Enzio
Riekert, that is a Hitachi turbo you've got there. I run a Mitsubishi (MHI) TD04HL-16T.
I'd suggest you do some research for specs and a flow map, but I would guess that BK might be right with respect to the turbine AR.
Re: HT18S-2S turbo on SR20
Posted: Mon Aug 22, 2011 10:31 am
by Riekert
Some pics:
Here are some specs:
“The twin scroll turbocharger concept was developed jointly by Mazda’s Department Five and by Hitachi, and is manufactured by Hitachi having been designated HT18S-2S. It’s turbine-side bearing area is now water-cooled, and the main body is further protected by high temperatures by a dual-skinheat shield. The 1 blade turbine, of impact design, is 64 mm (2.52 inch) in diameter. It’s scroll area, the nry path for exhaust gas, is divided into two passages separated by an integrally cast wall; one, called the secondary scroll, has a trap-door-like gate operated by intake vacuum. The turbine thus has two cross sectional area factors, A being the scroll’s smallest area as used in calculating turbocharger performance characteristics: 6.00 sq. cm (.93 sq. in) for the primary path and 9,48 sq. cm (1.47 sq. in) for the secondary. The other factor is R, the distance between the turbine-shaft center and the center of area A: 59.4 mm (2.34in) for the primary path, 60.4 mm (2.38in) for the secondary. Thus the twin-scroll turbocharger has two A/R ratios: 0.4 for the primary and 1.0 for the primary and secondary combined.”
Re: HT18S-2S turbo on SR20
Posted: Mon Aug 22, 2011 11:00 am
by Riekert
oh and some more info:
Mazda Series 5 RX7 HT-18, split pulse, Exhaust a/r 1.00, Compressor a/r .88.
"Ran an S5 HT-18 on my old SR20.
What a mistake....
Laggy and not particularly powerfull
Custom Manifold kept cracking, and exhaust housing wears where the wastegate actuator rod connects, rattles like fuck and dont seal properly.
Dont do it."
Re: HT18S-2S turbo on SR20
Posted: Mon Aug 22, 2011 11:04 am
by Riekert
so pretty much not the best deal then

haha damn

Re: HT18S-2S turbo on SR20
Posted: Mon Aug 22, 2011 11:23 am
by djtreble
Exhaust housing is WAAAY too big!
Re: HT18S-2S turbo on SR20
Posted: Mon Aug 22, 2011 11:44 am
by Riekert
jip

sigh....
so can I possibly change this out with one from a t25/t28/t3 ?