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I finally got my truck finished enough to start turning up the ams1000 and it seemed like it was needing a lot of dome pressure to make boost for my combo so i moved my fuel pressure sensor to one of the bottom wastegate ports and did a quick datalog.
relevant combo specs:
mostly stock 4.8 with tu0 cam
twin ebay t4 7268s with 3.5" downpipes, dual 44mm ebay gates with 3psi springs
2.5" tube out of turbos merge to 3" right before the ic, single 3" out of the ic loops around to the throttle body.
so anyway,
it looks like there is about 6 psi of pressure drop at 15psi. that seems pretty excessive. has anyone else used one of these intercoolers?
what is everyone else's experience with a budget liquid ic that will support 1000hp?
at the very least, i thought this was at least a little bit interesting.
In order to truly know how much of a problem this is, we also need to know the pre and post intercooler IAT's when the pressure drop was measured. Simply cooling your air causes some drop in pressure even without restriction. In this case, however, I doubt the news will be good.
edit-- Then again, is your fuel pressure sensor calibrated close enough to your map sensor at that pressure to know you are getting a valid comparison?
Post ic iats were within 10° of ambient so it's cooling well
I verified that both sensors read zero with engine off
The map sensor is a standard gm 3bar
The fuel pressure sensor has been compared to a mechanical gauge at base fuel pressure but I can re check that tonight to be sure the data isn't bad.
It wouldn't be a bad idea to test both sensors with compressed air and a regulator at pressure. Any 0-5V sensor will read 0psi at 0psi since that is the end of the range, typically 0.5V.
I'm interested to see what you find out. I ran the same cooler on a 13B rotary engine with a Borg Warner EFR 9180 and saw less power than I was expecting at the boost I was running. (540whp @25.5psi). If I was really in the mid 30s psi pre-IC, my exhaust back pressure would have been a lot higher and would make sense for the lower-than-expected power. Coincidentally, my IATs were also pretty low. I just had a GT500 pump and Roush heat exchanger, but IATs were under 100F doing 3 hours of 4th gear pulls on the dyno...
CX racing, frozen boost etc. all sell that same cooler. I've seen one from all three companies and the serial numbers where the same. Some company in china is making all of them. It can be had for $80 if you look harder on eBay. With that said 6psi is pretty high. Thanks for sharing the data.
It wouldn't be a bad idea to test both sensors with compressed air and a regulator at pressure. Any 0-5V sensor will read 0psi at 0psi since that is the end of the range, typically 0.5V.
the map sensor is absolute so it is not at the bottom of its range.
i plan to hook the fuel pressure sensor to the manifold and do a run to compare the graphs. they 'should' overlay perfectly. I believe that data should provide enough information to provide an accurate correction factor.
i also just ordered two egt sensors to put at the inlet and outlet of the ic. my efilive thing has two k-type inputs so i may as well use them.
Last edited by TrendSetter; Mar 31, 2017 at 09:03 AM.
How does the 4.8 do with those turbos? I have a pair of them going on a 4.8 as well.
its terrible, with 20psi on top of the gates its making 10psi at 6000 rpm.
that is why I looked into the pressure drop across the core. I just got this truck going yesterday so I am just beginning to explore ways to improve spool, but my initial impression is i messed up choosing either too small of a motor or turbos too large.
im going to give it the old college try though and hope to maybe even learn a little along the way.
and i thought my evo was laggy
Originally Posted by oscs
CX racing, frozen boost etc. all sell that same cooler. I've seen one from all three companies and the serial numbers where the same. Some company in china is making all of them. It can be had for $80 if you look harder on eBay. With that said 6psi is pretty high. Thanks for sharing the data.
I have heard treadstones are pretty good. are those different than the rest of the chinese intercoolers? i notice they sell water ic cores and might look into just making one.
its terrible, with 20psi on top of the gates its making 10psi at 6000 rpm.
that is why I looked into the pressure drop across the core. I just got this truck going yesterday so I am just beginning to explore ways to improve spool, but my initial impression is i messed up choosing either too small of a motor or turbos too large.
im going to give it the old college try though and hope to maybe even learn a little along the way.
and i thought my evo was laggy
hahaha dang that is pretty bad. I was going to run them on a 5.3 but its going to be the 4.8 for now. I should be up and running in the next week or so to see how they do. I have a Treadstone A2A on mine.
cheap turbos, cheap gates, cheap intercooler. surprised that there is problems? what surprises me is the use of the ams1000.
Im not asking for help as much as sharing my data and experiences with these parts and seeking similar from others with the same parts. but thanks for the useless input.
Thanks for the info/data! I picked up the T3 72/68’s to try on a 4.8 as well. (t3’s) So I'm super curious to see how this goes for you.
Which housings did you go with on the 72/68’s?
What 44mm gates? Pictures/link?
Have you measured turbo back pressure?
Converter type? What’s it stall to?
Gearing/tire sizes?
Fuel?
Those turbos are pretty large for a 4.8. Nice mild cam duration on the TU0 but I’d think the wide LSA would make it lazy down low. With a big twin setup on a small engine I’d want a nice tight LSA to help with low end. Loose converter, and bump the compression up to 10:1 at least. That was my plan anyway.
With only 3lb springs in the gate, those dome pressures aren’t crazy. Dome pressure can vary a ton with back pressure, and gate valve VS dome size. I’d be more concerned with turbo back pressure and pressure differential across the core. If 6psi is accurate, that’s huge! Can you put both sensors on the same side easily and verify the pressure readings match? If they do, pull the IC off and see how it responds at low boost. Should be night/day. 6lbs drop would be hard to believe. If the number are correct I’d send the IC back to CX racing and tell them to send you one that works.
Last edited by Forcefed86; Mar 31, 2017 at 12:39 PM.
Which housings did you go with on the 72/68’s?
What 44mm gates? Pictures/link?
Have you measured turbo back pressure?
Converter type? What’s it stall to?
Gearing/tire sizes?
Fuel?
exhaust housing is .96 ar. im not sure there were other options availabel in t4. if you know of smaller housings available id love to buy a couple to try.
wastegates are ebay wyntonm gates http://www.ebay.com/itm/44mm-4-PSI-T...-/172592801431
i havent measured backpressure, i assumed it would be very low considering the motor and turbos. i have full 3.5" dual exhaust. (maybe this is a poor assumption?)
converter is a billet 10.5 thats waaayyyy too tight. i was working on getting a new one when i realized i may want to approach the combo differently. right now i can stand on the brakes and only get 2000rpm at wot. im awd so foot brakes are as good as transbrake for this.
3.73s with 27" tires. it feels like it needs more gear.
93 octane pump gas
Those turbos are pretty large for a 4.8. Nice mild cam duration on the TU0 but I’d think the wide LSA would make it lazy down low. With a big twin setup on a small engine I’d want a nice tight LSA to help with low end. Loose converter, and bump the compression up to 10:1 at least. That was my plan anyway.
this motor is a pull-out from my single turbo gt45 t56 s10. i wrecked that truck and started on the full size. i originally had t4 gt35 6162s but when i got my evo i decided i wanted to push the truck harder so i got bigger turbos and planned to make the other needed changes as i go. so most of this mismatch isnt a big surprise for me, except the converter was supposed to be a lot looser than it turned out to be. i bought it used ¯\_(ツ)_/¯
With only 3lb springs in the gate, those dome pressures aren’t crazy. Dome pressure can vary a ton with back pressure, and gate valve VS dome size. I’d be more concerned with turbo back pressure and pressure differential across the core. If 6psi is accurate, that’s huge! Can you put both sensors on the same side easily and verify the pressure readings match? If they do, pull the IC off and see how it responds at low boost. Should be night/day. 6lbs drop would be hard to believe. If the number are correct I’d send the IC back to CX racing and tell them to send you one that works.
im going to move the pre-ic sensor to the manifold for one pull tonight to verify they read the same.
Originally Posted by 93camaro_zzz
Your dome pressure sensor seems all over the place in your log. You sure it's accurate?
its the original SSI sensor that comes with the ams1000 so its good quality, but i have not verified it. I am not running off co2, im running off a small air compressor with 1/2 gallon tank. This part has a little bit of room for improvement at the moment.
Oh man! Yea the .96’s are gonna be rough. They have .68 t4’s. REV-9 has a website. Might be able to contact them and try to buy housings only? The .8x T3 housings are massive, I'd stay away from those.
Never hurts to check, but yea… BP should 1:1 I’d guess. That cams not taking advantage of that BP IMO. But I get changing that stuffs a pain and expensive. Having an additional 6lbs of boost would be huge. That alone might fix it. But I’d address the converter next. 2000rpm is diddly. I told PTC to send me their $450 10.5” special. He said on a stock 4.8 (with my mild cam) it should stall to 4k on the trans brake.
Those minigates might have a relatively small dome compared to the valve? They look like the exact same housing on my 38mm gates. Wonder if they just tossed a larger valve and gate housing on it and used the same size dome as their 38mm line.
i moved the fuel pressure sensor and did a quick pull and got some comparative data. it looks like the fuel pressure is reading about 3.5psi higher than map. The line is pretty flat, so it seems to be more of an offset type error than a multiplier. so it looks like the pressure drop across the ic is peaking closer to 3.5-4 psi than 6. which is a good thing.
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CX Racing liquid ic pressure drop 
