HTB62/14 + Technicooler = Higher EGT, Lower Boost

[B-52]

Already searched for any threads pertaining to low boost or high EGTs. Already done the basic checks for loose clamps and connections and found nothing obvious. I haven't yet pressure tested the intake system since I don't hear anything suggesting a boost leak. Did lots of research before choosing turbo, and expected slower spoolup vs. stock due to larger exhaust housing.

What doesn't seem right is that under steady cruise, EGTs (all post-turbo) now avg roughly 750-800 VS 600-700 previously on the same roads w/stock turbo. With mild uphill acceleration, I can now very easily push 1000-1100. Hard uphill acceleration I can see 1200-1250, still climbing and need to back out of it. The max boost I have seen under any conditions is roughly 25-28 PSI vs. 35-38 PSI on stock turbo. What I expected with the 62/14 were lower EGTs due to the less restrictive exhaust housing, and equal or higher boost.

As noted in my sig, I have been running the Quad XZT (tow box), straight-thru MBRP muffler, and AFE intake - all in place for over a year. Anyone with a similar setup including the HTB and Technicooler who can give me some impressions of what normal boost & EGTs I should expect?

I have a TST sitting here just not installed yet. Can't decide if it will make the EGT problem worse, or if what I'm lacking is more fuel to keep the turbo lit.

Any help and/or opinions would be appreciated.

Cheers,
Mike

 

[RMalone]

I would definately expect higher egts and lower boost while cruising with the bigger turbo. The issue with high temps while pulling hills, I would think you would see more boost and lower temp so that seems odd. What happens when you romp on it?

 

[B-52]

From a standstill, if I just get rolling then mat it, the EGT climbs about as fast as the boost. The boost peaks at about 25-28 PSI and the EGTs willl keep cllimbing until I back out of it at about 1250 deg.

If I'm climbing a grade - top gear w/ locked TC - and mat the throttle, about the same as above.

What I thought should happen, especially on a grade, was that once the turbo came in, the boost should ramp up quickly to something near the wastegated value of about 40 PSI - i. e. more air movement would help keep the EGT down?

By the way, I cannot generate even minor smoke under any of the scenarios mentioned above. Seems like if I had a boost leak or some other intake issue, the result would be overfueling and some smoke. Is this sound reasoning?

Thanks all

 

[WCounts]

You may not be fueling enough to spool the 62/14. The tst will give you enough fuel and the timing will cool things down. You should see 40-42psi boost with the tst.

 

[CBrabec]

I agree that your not getting enough fuel. Before I added my tst, with my sps 62 and my ez I would get to maybe 30 psi and egt's were a tad higher than stock, but when I added the tst to the mix, my psi shot up to 45 psi then mellowed out at 38 at WOT. Just be aware, that if you add the tst and run it on higher settings (more than 5x5), your egt's will climb even higher and quicker, at least that's what I experience.

 

[Rams-n-Hogs]

My truck acts the same way. I have to be pushing some fuel to make the turbo work more efficiently. My fuel mileage is also lower if I'm not running enough fuel.



Jim

 

[TCDiesel]

Already searched for any threads pertaining to low boost or high EGTs. Already done the basic checks for loose clamps and connections and found nothing obvious. I haven't yet pressure tested the intake system since I don't hear anything suggesting a boost leak. Did lots of research before choosing turbo, and expected slower spoolup vs. stock due to larger exhaust housing.



What doesn't seem right is that under steady cruise, EGTs (all post-turbo) now avg roughly 750-800 VS 600-700 previously on the same roads w/stock turbo. With mild uphill acceleration, I can now very easily push 1000-1100. Hard uphill acceleration I can see 1200-1250, still climbing and need to back out of it. The max boost I have seen under any conditions is roughly 25-28 PSI vs. 35-38 PSI on stock turbo. What I expected with the 62/14 were lower EGTs due to the less restrictive exhaust housing, and equal or higher boost.



As noted in my sig, I have been running the Quad XZT (tow box), straight-thru MBRP muffler, and AFE intake - all in place for over a year. Anyone with a similar setup including the HTB and Technicooler who can give me some impressions of what normal boost & EGTs I should expect?



I have a TST sitting here just not installed yet. Can't decide if it will make the EGT problem worse, or if what I'm lacking is more fuel to keep the turbo lit.



Any help and/or opinions would be appreciated.



Cheers,

Mike

Is a boost fooler installed.

 

[bmoeller]

What doesn't seem right is that under steady cruise, EGTs (all post-turbo) now avg roughly 750-800 VS 600-700 previously on the same roads w/stock turbo. With mild uphill acceleration, I can now very easily push 1000-1100. Hard uphill acceleration I can see 1200-1250, still climbing and need to back out of it. The max boost I have seen under any conditions is roughly 25-28 PSI vs. 35-38 PSI on stock turbo. What I expected with the 62/14 were lower EGTs due to the less restrictive exhaust housing, and equal or higher boost.

Cruising temps are normal.



When I went from my stocker, to the PDR 40, The cruise boost dropped from ~ 5-8# (@55mph), to 2-3#. Peak boost went from 30+, to 20. Only had the #10 plate as the only fuel mod at the time. The 370s were still on order. Cruise EGTs @ 55, went from 5-600*, to 6-800*.



Boost @ 70mph, went from 15# to 7- 10#.



370s got me to 30#. New transmission and T/C got me to 40# (could finally load the engine).



Sliding plate full forward and adding the 191 delivery valves got me to 45#, and this is after installing the ATS exh. manifold, which lowered the peak boost by 5#.



With now having bumped the timing 2*, and having the DDP4 injectors, I hit 38#.



In the process of buying a HTT 64/14.