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250 WHP Supernatural 3.4 Build by La fiera
Started on: 10-07-2017 11:04 PM
Replies: 447 (13018 views)
Last post by: La fiera on 02-15-2020 06:43 PM
La fiera
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Report this Post01-27-2020 09:27 PM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Blacktree:

And that's with a Rube Goldberg valvetrain.

There's a guy on the 60degreeV6 forum revving his engine to 8000+ RPM in his race car. Look for username veekuusi. He also has a YouTube channel (also named veekuusi).


I've seen this guy's build but he screwd himself on the intake. Way too much plenum volumve vs runner lenght and width. He had too much area and too little lenght for that displacement, specially when he was allowed only -2 barrells per cylinders amount. He should've been in the 300-315WHP @ 8000rpms with that bore and stroke combo.

[This message has been edited by La fiera (edited 01-28-2020).]

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La fiera
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Report this Post02-13-2020 08:10 AM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post
https://youtu.be/ppTIEd8YCcs

Accelerated plans due to this!
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pmbrunelle
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Report this Post02-13-2020 10:04 PM Click Here to See the Profile for pmbrunelleClick Here to Email pmbrunelleSend a Private Message to pmbrunelleEdit/Delete MessageReply w/QuoteDirect Link to This Post
I think you used too much NOS:
https://youtu.be/pB-bN-RkJLM?t=52

The same weekend that I finished installing a MegaSquirt 2 in my previous 2.8 V6 Fiero (original stock engine), I drove 180 miles to the military base where I spent my Mondays-Fridays.

That Fiero saw full daily driver Monday-Friday duty right away, at the same time as I was building up my tune from scratch.

Driving the car in the morning following a cold start (lets say 50°F), there were a lot of pops and bangs for the first month or two until I started figuring things out. Nothing broke though... but your fabricated intake looks more delicate than the stock piece.

[This message has been edited by pmbrunelle (edited 02-13-2020).]

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La fiera
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Report this Post02-13-2020 10:34 PM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post




I'll fix that problem with this part and also getting in the habit of having the throttle opened a bit at least at the first couple seconds of hitting the start button.
E85 also comes with its own oxygen so I believe that was also part of the problem.

The support from MS told me that that happens sometimes because when powering up the ECU it triggers the coils on re boot.
The problem is more pronounced since I now have DIS and E85, before with the distributor and gasoline it was less likely to happen.
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pmbrunelle
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Report this Post02-13-2020 10:56 PM Click Here to See the Profile for pmbrunelleClick Here to Email pmbrunelleSend a Private Message to pmbrunelleEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by La fiera:
The support from MS told me that that happens sometimes because when powering up the ECU it triggers the coils on re boot.
The problem is more pronounced since I now have DIS and E85, before with the distributor and gasoline it was less likely to happen.


I know that with default settings, the fuel injectors give a priming pulse on key-on. This can be disabled if you wish by setting the priming pulse to zero.

I never heard that about the ignition coil(s). I'm going to check that on my car, with a spark plug outside of the engine where I can see it, and a friend turning the the key on/off.

If what you're saying is true, that's a serious flaw. If the engine is running at WOT while the CPU resets, then a spark could occur at a not-so-good part of the engine cycle, which could break things. I'm thinking of a scenario where a poor +12V power connection causes a power loss just long enough to trigger a CPU reset.

[This message has been edited by pmbrunelle (edited 02-13-2020).]

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La fiera
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Report this Post02-14-2020 09:07 AM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by pmbrunelle:


I know that with default settings, the fuel injectors give a priming pulse on key-on. This can be disabled if you wish by setting the priming pulse to zero.

I never heard that about the ignition coil(s). I'm going to check that on my car, with a spark plug outside of the engine where I can see it, and a friend turning the the key on/off.

If what you're saying is true, that's a serious flaw. If the engine is running at WOT while the CPU resets, then a spark could occur at a not-so-good part of the engine cycle, which could break things. I'm thinking of a scenario where a poor +12V power connection causes a power loss just long enough to trigger a CPU reset.



You are absolutely right! But besides this mishap I've never had any other problems while the engine running.
But just to clarify the misfire happened when I hit the START botton, not when I re set the ECU. The ECU was already powered up and I took a while to start the car.
I will check the priming like you suggest. I don't remember if I have the priming off after the engine is warmed.

[This message has been edited by La fiera (edited 02-14-2020).]

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lou_dias
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Report this Post02-14-2020 03:09 PM Click Here to See the Profile for lou_diasClick Here to Email lou_diasSend a Private Message to lou_diasEdit/Delete MessageReply w/QuoteDirect Link to This Post
I know you are trying to save weight but that does look like it's too thin...

As for a solution...just add a blow-off valve.
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La fiera
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Report this Post02-15-2020 06:43 PM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by lou_dias:

I know you are trying to save weight but that does look like it's too thin...

As for a solution...just add a blow-off valve.


You know, that was the first thing that came to my mind Lou!

I wanted to take the manifold out yesterday but wasn't feeling so well, It turns out I got type A Flu!
So I'll be out for a couple of days.
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