I have a grunter 1, front mount, enlarged plenum 10mm non compensated pump. Can I adjust the boost to 18psi and wind the fuel screw in fully myself? Or would I be best to get someone to tune with a AFR gauge because of variances across engines and pumps
How much boost can 1HZ-T handle? (4 Viewers)
- Thread starter nick4jc
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I personally like simplicity. Not really a whole lot that can go wrong with A2A.
And thanks it will get sorted out.
You would be crazy to just crank the fuel up without a boost comp and proper tune. This is how people blow up their trucks and say 1hz don't take well to a turbo.
XXi are running a HZT with 23psi on a Gturbo with their w2a & air box, video and stats freely available on FB. FWIW my 1HDT w/GT3071R runs 32psi, unfinished XXi tune, holds 20:1 up to 25psi@2000rpm, leaning off to 30:1 at 30psi/3000rpm. Spools from idle, and boosts hard. No dyno figures yet (ran out of time), but once I have a spare week, will be going back to fix the fuelling issue & run 20:1@32psi. Will post dyno figures then, but even now, it's sight out of mind better than when it was untuned on 15psi with just the fuel wound up a bit. Post turbo egt's never get over 400 even in 5th uphill on 30psi, intercooler works amazingly well, easily over 60 deg cooling (100+ down to 40ish)
Yeah post turbo EGT aren't any use as the harder the turbo is working, the bigger temp difference between pre and post readings.
Have you done anything to strengthen your 1HZ internally? Or are you after a good time, rather than a long time? Plenty of people have shown that power from a 1HZ isn't the problem. It's power with longevity that is hard to get.
Have you done anything to strengthen your 1HZ internally? Or are you after a good time, rather than a long time? Plenty of people have shown that power from a 1HZ isn't the problem. It's power with longevity that is hard to get.
what do you figure will let go?
Rings? Pistons?
Rings? Pistons?
That's the $10,000 question.
My money is on post turbo melt down , #6 ring lands. I wouldnt be surprised with all the questionable data on pre-post probe that the tuner is actually holding back on a full on tune . What does the tuner say the actual pre turbo egt's would be under full load compared to your actual post turbo readings . if it was me and i had your settup i would want the most i could get instead of guessing .
1 an 6 will always be the hottest one due to the manifold design
I see the AFR setting of 22:1 being a safety as the 1 and 6 will be slightly richer.
I still haven't seen the td42 vs 1hz pistons. We have oil squirters under the pistons of the 1hz.
As for post egt vs pre egt this will fluctuate between turbo types and their efficiencies.
In the end the "scientist" will not release intercooler comparisons with names or identifying supporting data. Reason being they don't want you buying their products. My eyes see it as if you truly have the best product, all so others can verify your claims and support them. I would love to see exact product comparisons.
I see the AFR setting of 22:1 being a safety as the 1 and 6 will be slightly richer.
I still haven't seen the td42 vs 1hz pistons. We have oil squirters under the pistons of the 1hz.
As for post egt vs pre egt this will fluctuate between turbo types and their efficiencies.
In the end the "scientist" will not release intercooler comparisons with names or identifying supporting data. Reason being they don't want you buying their products. My eyes see it as if you truly have the best product, all so others can verify your claims and support them. I would love to see exact product comparisons.
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Has anyone here been able to track down head studs for a 1hz? Plan on 30 psi plus and want to keep the head on
you shouldn't have a problem with the stock ones honestly. There are guys boosting that without stretching those bolts.
mudgudgeon
Resident galah
Agreed. New, OEM bolts should be capable, they've certainly been tested.
Honestly I wouldn't bat an eye running a 1HZ at 25lbs assuming the supporting modifications were in place.
Thats Clutch, intercooling, turbo and proper pump fit to match the job. I can't stress how important these and a proper tune is for longevity.
I will say to anyone though that it will be cheaper to buy a 1hd-t for $5k and do an engine swap though if you want to do the turbo route.
Thats Clutch, intercooling, turbo and proper pump fit to match the job. I can't stress how important these and a proper tune is for longevity.
I will say to anyone though that it will be cheaper to buy a 1hd-t for $5k and do an engine swap though if you want to do the turbo route.
Yeah I already had the motor built to turbo spec and have a 12mm pump with a manualised auto behind it so my only concern is the head staying on.
Tell me more. A442f? I'm not aware of a valvebody (or documented modifications) that would allow this.
Yeah A442f electrical box, you dont need a valve body to do it.
Although a lot of places will tell you that you can't do it without the valve body they are wrong, it's just because if they tell you how to manualise it they can't sell you a valve body.
Is this an actual factory 1HZ-T? Perhaps this will quiet the naysayers who don’t think such a motor ever actually existed.
EDIT: realize it says 1HD-T in the description but the valve cover looks 1HZ to me. Thought 1HD-T valve cover was smooth/no ribs in the casting. But I’m far from an expert on such things!
EDIT: realize it says 1HD-T in the description but the valve cover looks 1HZ to me. Thought 1HD-T valve cover was smooth/no ribs in the casting. But I’m far from an expert on such things!
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It's a 1HD-T.
Injectors are a dead give away. That's 100% a 1HD-T
mudgudgeon
Resident galah
1HZ and 1HD-T share the same valve cover.
Valve cover changed with the 24 valve engines
