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I have a jeep I plan on swapping a 4bt into I have a engine allready with a TH400 it has a H1c turbo on it now nothing wrong wit hit but some say it will suck performance wise? I plan on running 3.73 gears and 37-42" tires the jeep will weight around 4000-4500 lbs it will be a daily driver and weekend wheeler I think i have a 18-21 exhaust housing some say i should swap to a 12 or a 9 CM unit on the back of my H1c compressor im asking for more advice will the 9CM be too small? I see dodge 5.9 autos used them I dont need upper rpm power just want it to accelerate hard and pull up to its 2800 gov speed some say the 12 will give me the best of both worlds just want t oknow anyones personal experience wit hany of them?
 

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I have a jeep I plan on swapping a 4bt into I have a engine allready with a TH400 it has a H1c turbo on it now nothing wrong wit hit but some say it will suck performance wise? I plan on running 3.73 gears and 37-42" tires the jeep will weight around 4000-4500 lbs it will be a daily driver and weekend wheeler I think i have a 18-21 exhaust housing some say i should swap to a 12 or a 9 CM unit on the back of my H1c compressor im asking for more advice will the 9CM be too small? I see dodge 5.9 autos used them I dont need upper rpm power just want it to accelerate hard and pull up to its 2800 gov speed some say the 12 will give me the best of both worlds just want t oknow anyones personal experience wit hany of them?
i think the gears should be 4.11
 

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I run 4.56 gears with 37s and love it. Anyway, about the turbo. I ran the stock H1C, a WH1C with a 12cm, and now a HY35 with a 9cm. The HY35 with the 9cm is by far the best, spools fast, makes 35 lbs of boost and the EGTs are great.

The H1C with a 12 would prob be ok, mine spooled ok with the stock 16cm. But with the little bitty impeller it ran out of breath on the top end fast
 

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I'm running 4.88's on my TJ on 35's... Too steep.

need 3.73's or MAYBE 4.10's....

No tach yet, but I'm getting 600km/city, and only 400km/hwy...

Revs too high, however, the turbo spools nicely and away we go.
==Scotty
 

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My Jeep was running the 3.73 with 33" tires and it did good. I have upgraded my turbo to a 14 cm3 turbine housing and a 54mm compressor. I am getting max about 26 psi of boost and around 1250 degrees of EGT. I am in the process of upgrading my Jeep to the Dana 44 Front and rear axles with the 4.10 gears and have also put 35" tires on it. Hopefully this week I will have it out of the garage and can give you a better report on how it is doing.
 

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the stock turbos don't suck at all IMO, there is just a lot more out there.. I ran my stock turbo for at least a year and was pretty happy with it, particularly with a wide-open exhaust... Hope it helps..
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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3.73 would give about 2290 at 65 with 37's or about 2000 at 65 with 42's, go with the 42's and keep the 3.73's.
3.54s would be ideal.
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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Discussion Starter #10
this is PERFECT info!!! I really thank all for the quick responses. I see the ones that are using alot of manual overdrives can go steeper like 4.11 and 4.56, and if I had a OD I would now doubt choose 4.11. I dont have any probs with a manual just that sometimes when im 4 wheeling in sand or mud getting that truck 5 speed to shift fast is about imposable. plus the 4bt only spins 2800RPM or 3200 with the spring change , I am leaving those settings alone due to the fact i like it to be conservative I use the rev limiter alot on the 2.5 and I kinda like it there so i cant get to stupid and :nuke: it up.
I also talked to a bread co. mechanic and the trucks that had the SM465 and turbo 400s and the ones with big truck 5 speeds all 1.1 final drive ratios said max speed was 60-65 and they were running 4.10s and roughly 31" tire he also noted that the trucks would pull the higher gear like a 3.50.

sounds like i might be looking for a HY35 turbo setup now :dustin:
 

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The HY35 with the 9cm is by far the best, spools fast, makes 35 lbs of boost and the EGTs are great.
Still have the WG hooked up and working, or welded shut?
 

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Only thing that I would question with the HY35 is how it would act during those higher RPMs (3000'sh)?

I don't know much about turbo's but I'd be concerned about it falling flat on it's face.
 

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Only thing that I would question with the HY35 is how it would act during those higher RPMs (3000'sh)? I don't know much about turbo's but I'd be concerned about it falling flat on it's face.
They are used on 6BT truck engines, so why would you think it would be a problem for a 4BT?????
 

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Check out the Piers Diesel HX35. Modified housing and pinwheel spools up fast as hell and cools my EGTs a bit. Very popular for the 300HP 6bt crowd.
 

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Very popular for the 300HP 6bt crowd.
Not sure if it would be the best match, seeing as how we have two less cylinders. It would be nice to see some real world experience.
 

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Aurora 2000

I was reading about the ATS Aurora 2000 in an old TDR. It seems like a good candidate for our 4bt. I kept thinking it would be a great Turbo for the 1/4 mile pile. Obviously real world experience would be great here, and the turbo is spendy.
 

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Only thing that I would question with the HY35 is how it would act during those higher RPMs (3000'sh)?

I don't know much about turbo's but I'd be concerned about it falling flat on it's face.
My HY35 spools good all the way up to 3200. Motor pulls hard until the gov.

When I was using the stock H1C the top end fell off hard!
 

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HTT, High Tech Turbo has some nice H1C [and others] turbo upgrades and reasoable prices. They have compressors, turbines etc. form most anything, plus compounds and hybrids. I got a Stage II from them, but looked on their web site today and didn't see it, only Stage III, IV. Might give them a jingle and ask them.
 
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