Just a few HT 18S-2S questions
#1
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Just a few HT 18S-2S questions
I've been looking around this site and various others with little or no luck of finding real info about this turbo besides it is from the 2nd gen TII's. I did read in some post that it is similar to a T3/T4 setup, but it is much smaller than any hybrid i've seen before, so maybe I just misunderstood it.
Also what is stock boost on these engines. I'm planning on using a 18s s2 on my 87 325 custom low boost setup. I also need to know what exhaust flang i'm going to need to match up with the hot side of the turbo. If it's really a t3, than i won't have to go about finding a stock turbo manifold and hacking it up.
Also what is stock boost on these engines. I'm planning on using a 18s s2 on my 87 325 custom low boost setup. I also need to know what exhaust flang i'm going to need to match up with the hot side of the turbo. If it's really a t3, than i won't have to go about finding a stock turbo manifold and hacking it up.
#3
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Originally Posted by avus_e30
Also what is stock boost on these engines. I'm planning on using a 18s s2 on my 87 325 custom low boost setup. I also need to know what exhaust flang i'm going to need to match up with the hot side of the turbo. If it's really a t3, than i won't have to go about finding a stock turbo manifold and hacking it up.
You'd be lucky if you see any boost until 5,000RPM...
The inlet and outlet flanges are all proprietary Mazda stuff - no, it doesn't fit anything else out there.
It all needs to be custom made.
Seriously, go look elsewhere for a turbo application for your needs.
Look at eBay - there are a LOT of T3's being sold there for cheap.
If not, we got a T3 "60" for sale for $400 brand new...
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-Ted
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Originally Posted by avus_e30
Also what is stock boost on these engines. I'm planning on using a 18s s2 on my 87 325 custom low boost setup. I also need to know what exhaust flang i'm going to need to match up with the hot side of the turbo. If it's really a t3, than i won't have to go about finding a stock turbo manifold and hacking it up.
You'd be lucky if you see any boost until 5,000RPM...
The inlet and outlet flanges are all proprietary Mazda stuff - no, it doesn't fit anything else out there.
It all needs to be custom made.
Seriously, go look elsewhere for a turbo application for your needs.
Look at eBay - there are a LOT of T3's being sold there for cheap.
If not, we got a T3 "60" for sale for $400 brand new...
![Smilie](https://www.rx7club.com/images/smilies/smile.gif)
-Ted
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Hmmm, a/r being too big? Isn't the rotary engine like a 1.3L? If anything I thought that it would be too small. It's going on a 2.5L inline 6. Can someone explain this to me a bit more. I just didn't think the rotary could flow that much air with such a small displacement.
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Originally Posted by avus_e30
Hmmm, a/r being too big? Isn't the rotary engine like a 1.3L? If anything I thought that it would be too small. It's going on a 2.5L inline 6. Can someone explain this to me a bit more. I just didn't think the rotary could flow that much air with such a small displacement.
The 1.3 liter 13B runs like a 2.5 to 3.0 liter 6-cylinder, *but* due to it's strong exhaust pulses, it's able to run large A/R's without a penalty to turbo response.
-Ted
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How big and A/R are we talking here? Also how much is a rebuilt 18s worth to people in the rotary world, like I don't want to be stuck with a setup i'm unhappy with.
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How big and A/R are we talking here? Also how much is a rebuilt 18s worth to people in the rotary world, like I don't want to be stuck with a setup i'm unhappy with.
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Can the turbine housing be ditched for another more favorable T3, or is that another thing that can't be done do to it being a mazda only applicable turbo?
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I don't think the stock HT-18 turbine wheel will fit into a standard T3 housing.
The Garrett turbine housings bolt onto the Hitachi center, but that doesn't necessarily mean the turbine wheel will work correct or spin freely.![Frown](https://www.rx7club.com/images/smilies/frown.gif)
-Ted
The Garrett turbine housings bolt onto the Hitachi center, but that doesn't necessarily mean the turbine wheel will work correct or spin freely.
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-Ted
#13
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Hmmm, I think the best bet is to just try another turbo, i'd hate to try and make it work and hack up a basically new Ht 18. Thanks for all the help and the quick replys.
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