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Is that swap worth it over just an OEM opti?
I’d say that’s a decision you’d have to make. For me and what I’m planning with the car, 100% worth it.
If you're staying stock I wouldn’t spend $1800 on it. You can buy a lot of optis for that.
The swap can help defer its cost if the pcm uses a ... fully enabled Aussie operating system ...
 

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The stock LT1 PCM was never designed to handle boost. There are two ways to back-door it, but you have to know what you're doing. The other thing is that it opens up the tuning window to HP Tuners and guys familiar with that. Although these Gen2 LT1s need more advance than LS motors so a tuner who doesn't understand that will leave a lot of power on the table.
 

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24x can be done cheaper than the TorqueHead kit if you're not afraid of wiring and junk yard parts and with my very aggressive cam the 0411 PCM has some additional parameters such as dwell which allowed me to achieve much smoother operation at low throttle low speed conditions.

-Brian
 

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24x can be done cheaper than the TorqueHead kit if you're not afraid of wiring and junk yard parts and with my very aggressive cam the 0411 PCM has some additional parameters such as dwell which allowed me to achieve much smoother operation at low throttle low speed conditions.

-Brian
Don't you lose sequential injector control with the 4x crank-only conversion, which then precludes your ability to delay injector timing until after exhaust valve close at idle?
 

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Is that swap worth it over just an OEM opti?
First, I am a big Torqhead fan, and I love mine.

However, my answer to your question is "NO, not at all".
If you can still get a good mitsubishi sensor optispark, if you haven't gotten frustrated and stranded by multiple opti failures, if you don't have a complex set up (power adder, etc.), if you aren't looking for big horsepower, and most of all; if you don't require finding someone to "tune" the car, then you have no need for a Torqhead conversion.

Finding someone to tune our old cars is difficult, and that gets exponentially harder if you require a special tune. When I checked my area for tuners, no one wanted to touch my car (at any price). Knowing I planned on leaning on my motor AND using a power adder, I did not want to go with a mail order tune. My only choice for a reputable local tune was to upgrade the PCM to an LS style computer. Since I don't understand wiring at all, the Torqhead kit made this task easy for me.
 

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Ehhh, how many miles would you have to travel under lean cruise conditions to make a noticeable cost savings?
Based on my driving, which is mostly city / metro / urban, but includes 500 miles a month of highway driving in mostly 4th with a lil bit of 3rd, and slightly tweaking the enleanment conditons for a lil more enleanment than the Aussie op sys originally allows ...
... using a Tahoe ...
25 months, assuming the discipline to stay under 75MpH.
B- & D-bodies (lighter and less bricklike than Tahoes) would get into Lean Cruise sooner and stay in Lean Cruise longer than Tahoes.

However, with 8 coils and a 12200411, even without ANY Lean Cruise enablement, better MpG is possible, if the initial tune is calibrated with real-time refinements specifically for that purpose.
Is that swap worth it over just an OEM opti?
Strictly in terms of MpGs, I would say, it depends on how the car is driven, how long the car continues to use the conversion, and whether or not - or to what extent - the initial tune is refined to take advantage of its potential.
 

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Previous post strictly focuses on fuel economy savings.
Is that swap worth it over just an OEM opti, one coil, and a pcm more tuners will soon avoid?
(Quote edited by me, duhr.)
OBVIOUSLY there are TorqHead conversion benefits which cannot be quantitatively measured.

There are some ... people ... who think tuning of the original pcm is not 'worth it'.
Although 16188051 or 16214399 tuning (without real-time fine-tuning refinements) may not yield MpG improvements, there are other good reasons for even a mere mail-order tune (that the 'un-tuned' choose to ignore, at their losses).

I think of those reasons as analogous to the reasons why one might do a TorqHead conversion.

Everyone gets to decide for themselves of course - duhr.
Had I any LT1 car (B- D- F- or Y-), already in good (or better) mechanical shape, and the money to spare for a TorqHead conversion, I'd consider it a long term investment worth making - unless I had reason(s) to think I wasn't keeping the car for at least another few years.
 

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Don't you lose sequential injector control with the 4x crank-only conversion, which then precludes your ability to delay injector timing until after exhaust valve close at idle?
I did the cam and crank sensors. (EFI Connection). I already HP Tuners for my GTO so I figure my spend was ~$700 in parts and another $2-300 in tuning. What's a good Opti replacement cost these days?

-Brian
 

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I’d say that’s a decision you’d have to make. For me and what I’m planning with the car. 100% worth it. If your staying stock I wouldn’t spend $1800 on it. You can buy a lot of optis for that.
If you have any questions re: tuning, I may be able to provide some help through my experience learning the 0411 tuning side
 

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Discussion Starter · #33 ·
If you have any questions re: tuning, I may be able to provide some help through my experience learning the 0411 tuning side
Appreciate it! I do have a few questions with Hp tuners and what’s readable as pids.
 
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Hi Blueallie. I'm strongly considering doing the same Torqhead/Meziere conversion on my wagon. After a few months, how do you feel about each of the parts? Are you happy you spent the time and money?
 

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Discussion Starter · #36 ·
Hi Blueallie. I'm strongly considering doing the same Torqhead/Meziere conversion on my wagon. After a few months, how do you feel about each of the parts? Are you happy you spent the time and money?
Absolutely happy! No issues at all with either. WP actually runs a little cooler than what the car did before. Curious about how that’ll affect my heater this winter though.
 

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H2Opump actually runs a little cooler than what the car did before.
Curious about how that’ll affect my heater this winter though.
Does your heatercore still have its foam ring that prevents air from sneaking past it intact?
Do the rest of the hidden ducts and pathways behind the dashboard operate properly?

Are you using a 160F , 180F , or 195F tstat?
 

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Discussion Starter · #38 ·
Whatev
Does your heatercore still have its foam ring that prevents air from sneaking past it intact?
Do the rest of the hidden ducts and pathways behind the dashboard operate properly?

Are you using a 160F , 180F , or 195F tstat?
I haven’t touched anything on the heater parts inside. I’m guessing it all there. Haven’t dropped the lower access panel to check. Stock tstat. Engine runs cooler now. I did knock the gunk out of the block, flushed with Theroflush when changing the knock sensors to obd2.
 

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... haven’t touched anything on the heater parts inside.
I’m guessing it all there. Haven’t dropped the lower access panel to check.
Stock tstat. Engine runs cooler now.
I did knock the gunk out of the block, flushed with Theroflush when changing the knock sensors to obd2.
Then you can simply check that it all works as it should, by, for example, jamming a meat thermometer into a random vent with the temp selector knob set @ 'hottest'.
If the air coming out of the vent reaches 115°F / 46°C, then it's all working as it should.
If the air coming out of the vent exceeds 130°F / 55°C, then you should be damn proud.
 
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Absolutely happy! No issues at all with either. WP actually runs a little cooler than what the car did before. Curious about how that’ll affect my heater this winter though.
Cool, thanks for replying. I suppose you could swap out your thermostat if heater performance suffers, but I bet it will be fine with the stock one. I've heard from a few people with other engines that their electric pumps keep things about 10 degrees cooler and I'm hoping that the pump will let me run a little more advance on the timing. I would assume that the higher average coolant flow rate keeps the head temps lower and the block temps higher for any given engine temperature, but there may be something that I'm missing.
 
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