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Discussion Starter #1
I'm shopping for a full kit (diy install) but as with most things mechanical a recommendation is favourable. I've come across (not literally, or at least not yet), and aquamist website that seems to look the ticket. Are there any UK owners out there who'd be willing to offer me advice and share a build thread at all in the spirit of petrolhead power hungry mania please?

Cheers.
 

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Well I'm not over there but
I went with the Nitrous Express kit before I SC because it had a contact switch I mounted on the gas pedal so it came on at about 95% throttle.





The only place to mount the small kit bottle was in front of the air filter.


There's a red low level light and a green when on light
I put here.



I decided to tap the WW bottle that holds 1 gallon at where the low level light comes on but it could be tapped lower.
I put the pump inside the bottom cover.






This kit would drop the IATs by 14-15 degrees like this ambient 69 intake 55
pic



After I put the Procharger on and went with a Snow adjustable boost controller it would keep the IAT's steady under boost instead of going up 20+ degrees.
I added a universal gauge pod I cut down and moved the green on light to it.

 

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Discussion Starter #3
Comprehensive thank you.
So does your meth kit (previoulsy) simply just squirt into the air intake the switch is made? I'd thought for some reason that a meth kit would piggy-back the injectors similar to an lpg install, eg meth injector per each fuel injector.
So have you used your washer bottle for the meth, and are you using this to clear the windscreen too :-D ?
Also is the kit as basic as a microswitch and a pump and was your intention to keep the cylinders cool and not complete the install as a direct performance upgrade?
 

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Comprehensive thank you.
So does your meth kit (previoulsy) simply just squirt into the air intake the switch is made? I'd thought for some reason that a meth kit would piggy-back the injectors similar to an lpg install, eg meth injector per each fuel injector.
So have you used your washer bottle for the meth, and are you using this to clear the windscreen too :-D ?
Also is the kit as basic as a microswitch and a pump and was your intention to keep the cylinders cool and not complete the install as a direct performance upgrade?
Not sure what you mean by not completing the install.
And yes I have tapped the ww bottle and use the same fluid to wash my windshield and back glass.
The Procharger comes with a smaller tank to make room for the boost hose.
I have a 1/3 drum of methanol I got from a racing buddy so I mix up my own 50/50 fluid.
Windshield washer fluid is 65/35 water/alcohol.
When I came to the forum after I bought my SRT in 2016 some other esteemed members who raced their SRTs recommended windshield washer fluid ie meth as having performance benefits on NA 392s and swore by it.
Keeping the IATs low gives better timing and more fuel plus the meth is more fuel as well.
If you don't have boost you need something to trigger it and a micro switch on the gas pedal is it.
When I did the Procharger I switched to a Snow controller that senses boost.
The meth kept the IATs constant.
But I still wound up breaking a piston.



 

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Discussion Starter #5
Thanks again, do you think you’d have damaged your piston without the meth, or was this purely due to the supercharger install?
I meant that you’d installed the meth to lower intake temperatures and increase engine longevity as opposed to chasing power gains, and had not completed the install purely as a performance upgrade on its own.
 

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Thanks again, do you think you’d have damaged your piston without the meth, or was this purely due to the supercharger install?
I meant that you’d installed the meth to lower intake temperatures and increase engine longevity as opposed to chasing power gains, and had not completed the install purely as a performance upgrade on its own.
I like fiddling with this kind of stuff.
It was power gains at first without the SC but after it was for engine longetivity.
The SC was only putting out 5 psi max and I wanted to up it to 6 or 7 as that was considered safe.
We figured to tune it without meth like when it was tuned before in case the meth ran out or the kit malfunctioned.
We turned off the meth for the tuner to retune it with a smaller pulley and it broke a ring land on the dyno at 4000 rpm.



The stock cast piston has a weakness for SC due to the valve relief.



Mahle pistons in the Arrington 426



 

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After using those piston, did you turn up the boost?


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Yes.
The 426 is 34 cu/in bigger than the 392, about 8% more displacement.
With the larger ATI harmonic balancer and the smaller 4" pulley on the Procharger head it came out to 7 psi with 542 awhp or about 620-640 hp at the engine
That's about it with the stock fuel pump.
If I add a boost a pump I can go more but while all this was being done which took 7 months I bought a 707 hp dealer demo 2018 Trackhawk with 10,000 miles on the clock so now the SRT is my winter car 😄







 

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Yes.
The 426 is 34 cu/in bigger than the 392, about 8% more displacement.
With the larger ATI harmonic balancer and the smaller 4" pulley on the Procharger head it came out to 7 psi with 542 awhp or about 620-640 hp at the engine
That's about it with the stock fuel pump.
If I add a boost a pump I can go more but while all this was being done which took 7 months I bought a 707 hp dealer demo 2018 Trackhawk with 10,000 miles on the clock so now the SRT is my winter car







Thank you, I have a 14 with a whipple and thinking about just going ahead and doing the cam, rods, and pistons. I have been looking at the meth kits too for added protection.


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Yes.
The 426 is 34 cu/in bigger than the 392, about 8% more displacement.
With the larger ATI harmonic balancer and the smaller 4" pulley on the Procharger head it came out to 7 psi with 542 awhp or about 620-640 hp at the engine
That's about it with the stock fuel pump.
If I add a boost a pump I can go more but while all this was being done which took 7 months I bought a 707 hp dealer demo 2018 Trackhawk with 10,000 miles on the clock so now the SRT is my winter car







Both rides look really good BTW! What springs are you on?


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Discussion Starter #12
Do I need a map/tune for when I add the meth? Your comment about leaving the ecu stock for when there is no meth is a good shout, but will I see any power gains without a remap?
 

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No retune required.
A dynotune is $350.00 or more.
I never tried to test it for more power.
WOT felt stronger or maybe I wanted to think so.
We're not talking about a big power adder maybe 5 hp.
The pcm will adjust the timing and a/f ratio based on the lower IAT.
After tuning for the forged SC 426 New Era Performance told me the meth wasn't really adding anything so I set it to come on at 6 psi instead of 2.
Lasts a lot longer before needing a refill.
Since I have it it keeps the IATs only 15-20 over ambient on WOT at that setting.
 

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Discussion Starter #14
Oh my goodness, approx 5hp isn't worth the trouble or expense so I'm grateful you've shared that info. I can add octane booster on each fill-up that I guess will produce the same un-noticeable results :-D
In the UK our air is usually dense/humid and our summer temperatures are laughable so I don't think I'm gonna struggle with high iat's.
Drag strip racing also isn't popular in my area unfortunately.
I've read heaps of internet garble regarding the meth and it looks like for n/a it's not beneficial. Youtube is filled with dreamers and people who tell porkies I've found.
A while back you said I should just save for a trackhawk and have the srt for what it is, I'm starting to belive that's my best port of call as the performance is brutal for a bus this size. Doubtful I'd sell the srt though, I'd like to 'mad-max' it by welding spikes and iron railings to its front end, an exterior roll cage and bars across the windows. Then straight pipe the exhaust.
 

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Oh my goodness, approx 5hp isn't worth the trouble or expense so I'm grateful you've shared that info. I can add octane booster on each fill-up that I guess will produce the same un-noticeable results :-D
In the UK our air is usually dense/humid and our summer temperatures are laughable so I don't think I'm gonna struggle with high iat's.
Drag strip racing also isn't popular in my area unfortunately.
I've read heaps of internet garble regarding the meth and it looks like for n/a it's not beneficial. Youtube is filled with dreamers and people who tell porkies I've found.
A while back you said I should just save for a trackhawk and have the srt for what it is, I'm starting to belive that's my best port of call as the performance is brutal for a bus this size. Doubtful I'd sell the srt though, I'd like to 'mad-max' it by welding spikes and iron railings to its front end, an exterior roll cage and bars across the windows. Then straight pipe the exhaust.
Other than air filters and catbacks which are only really sound performance there's not much worth doing for more power.
I had long tube headers put in at my local 3 miles away place with a dyno before the SC for $2800.00 and got 10-15 hp and a sweeter exhaust note.
SC the SRT was a big misadventure that took 7-8 months and cost $20k.
I wound up taking it to another much bigger place owned by the FCA dealer I bought the Trackhawk from to dynotune it because my local tuner and the 3-4 mechanics at the place who tuned it when I SC the 392 which worked good somehow couldn't get the 426 to stop stalling.
The FCA dealer offered up his tuning services when I told him about my troubles while purchasing the Trackhawk which he personally drove as a demo for 4 months.
They had about 40 cars they were working on at their multi building place.
Serendipity is my middle name :cool:
I found something I wasn't looking for (y)
New Era Performance got it a lot better and WOT tuned it but it still stalled occasionally on a slow turn like pulling into a driveway unless you blipped the gas pedal twice.
We checked all the hoses and vacuum lines.
Then after logging it stalling with HP Tuners numerous times to have my local tuner or someone look at it and driving it for 6000 miles it mysteriously fixed itself and stopped stalling :)
Hasn't stalled in 2000 miles.
It's running well now and I've put 8000 miles on it as my winter car :LOL: miles I've kept off the Trackhawk for warranty.
 

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Discussion Starter #16
Yeah thanks, I’ve read through most of your old posts regarding the build. The experience you’ve had has been very informative and it’s saved me thousands of pounds and heaps of frustration so thank you.
I’m impressed with the srt, so much so I’d get the trackhawk when I have some more pocket money.
 

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I take risks.
I have a lift and my own private shop in my huge industrial building to fiddle with this stuff and time to do it.







 
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