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Discussion Starter · #1 ·
I have a spare H1C turbo that I'm going to rebuild. I read the " Turbo Tips" thread and started thinking about modding the turbo while I'm at it. Here's my plan- change the impeller and compressor housing to the 4" that the early 6bt's used. Then put a 12cm turbine housing on. I haven't checked parts prices yet, but it may be cheaper than buying an HX35, with the advantage of being rebuilt. A used HX35 is about $500.00 around here.
What do you think? Good, bad or ugly, let's hear it. Am I crazy?
 

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Making a hybrid turbo brings about a lot of consequences.

Setting one up with a smaller exhaust housing and bigger compressor, biases it towards low rpm boost. It also means you're going to have very high exhaust backpressures at higher rpm.

Hybrid turbos work best with wastegated exhaust housings. Otherwise your exhaust turbine isn't capable of flowing the air that the compressor can deliver.
 

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I agree with the replies. I contacted HTT [High Tech Turbo] and followed their advice, purchasing their Stage II compressor, which I think was 56cm. That will be used with my stock H1C 16cm exhaust. 16 will dump into full 4" exhaust with low restriction muffler, or maybe just a resonator.

This will give better boost, while keeping EGT's fairly low with 16 exhaust. I wanted better power but also low EGT towing capabilities. For more power without towing consideration you might want Stage III, and HTT can advise on a good setup. My stage II was only about $200 delivered, uses stock Holset parts, and converts H1C to HY35 as I recall? I need to call them to jog the memory as to what performance level Stage II provides, and haven't installed it yet either. Nice guys to deal with and a good reputation.
 

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Discussion Starter · #5 ·
In the "Turbo Tips" it talks about swapping turbos (HX35 & HY35) and modding the original H1C. I'm just wondering if there any other combinations.
That's why I asked if an H1C from an early Dodge would work. It has a larger compressor side,which would give more air, with a smaller turbine housing to spool faster. How does the compressors compare on the H1C, HX35, and HY35?
North of the border things are a little more expensive, but I do need to look around.
 

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In the "Turbo Tips" it talks about swapping turbos (HX35 & HY35) and modding the original H1C. I'm just wondering if there any other combinations.
That's why I asked if an H1C from an early Dodge would work. It has a larger compressor side,which would give more air, with a smaller turbine housing to spool faster. How does the compressors compare on the H1C, HX35, and HY35?
North of the border things are a little more expensive, but I do need to look around.

Such a setup will build boost earlier, but will also create a large exhaust restriction. Strangling your engine at higher revs.

It's all about compromise, pick your best operating point and build the turbo to suit it.
 
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