NOS... What would happen?

[2nd 392]

Come on man it was a cat with aviator head gear on starting it..

Give him a break— he didn’t ask “ what Carb should I get?” Don’t think I will ever forget that one.

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[old schooler]

NOS comes with T66 turbos and a motec exhaust system..

 

[Retrograde]

Best thread of the day!

Admittedly, I asked partly for the entertainment value, but partly because I was (somewhat) serious, asking theoretically/hypothetically...

Back in the day, if you ran giggle gas you also had to manually add fuel to the intake stream in sufficient quantity to make a burnable mixture as it entered the engine. And you had to do it within the confines of your compression ratio and the strength of the engine itself, because you got no timing mercy from your vacuum advance distributor.

But things are different now...

So let's back off the 'generous' shot and go a little milder, say a 100 HP shot. Would the exhaust O2 sensors pick up on the lean condition, and would the ECM then be fast enough with more fuel through the injectors?* Would the knock sensors & ECM back off on the timing sufficiently to keep the whole thing from grenading, or would they say 'fuck this' and just shut the whole show down?


*Side note: Does anyone know what the max fuel throughput/HP our injectors will support?

 

[2nd 392]

Admittedly, I asked partly for the entertainment value, but partly because I was (somewhat) serious, asking theoretically/hypothetically...

Back in the day, if you ran giggle gas you also had to manually add fuel to the intake stream in sufficient quantity to make a burnable mixture as it entered the engine. And you had to do it within the confines of your compression ratio and the strength of the engine itself, because you got no mercy from your vacuum advance distributor.

But things are different now...

So let's back off the 'generous' shot and go a little milder, say a 100 HP shot. Would the exhaust O2 sensors pick up on the lean condition, and would the ECM then be fast enough with more fuel through the injectors?* Would the knock sensors & ECM back off on the timing sufficiently to keep the whole thing from grenading, or would they say 'fuck this' and just shut the whole show down?


*Side note: Does anyone know what the max fuel throughput/HP our injectors will support?

Wouldn’t a blower be a better option? Available systems are dialed in, extra power at all times, once installed require little maintenance. And as you said this isn’t the old days, where you just put an extra fueling plate under the carburetor to get the extra shot.?

 

[AFD]

OP's headed to Race Wars? ?

 

[Retrograde]

Wouldn’t a blower be a better option?

Absolutely, blowers are are always the better option. But they're spendy. A bottle & a plate are only a few hundred bucks.

Back in the 80s & 90s when we were putting lumpy cams in TB injected Small Block Chevies, you could get about 300HP out of a TBI unit and then you ran out of fuel through-put. At 300 HP the mixture would lean out, the ECM would cut back the timing in response to the knock, and the whole thing would fall on its face. The work-around was a TBI unit & controller from a Big Block (more fuel).

But the last engine I built was in 1992, and I've not been into engine mechanics in 30 years. So in a broader sense, what I'm asking is, do these motors still work on those principles? "Nitrous" is just French for "more air", and if we introduced some into the intake of one of these engines, would the electronics try to adapt, or would it just decide something is outside parameters and shut down?

 

[2nd 392]

Absolutely, blowers are are always the better option. But they're spendy. A bottle & a plate are only a few hundred bucks.

Back in the 80s & 90s when we were putting lumpy cams in TB injected Small Block Chevies, you could get about 300HP out of a TBI unit and then you ran out of fuel through-put. At 300 HP the mixture would lean out, the ECM would cut back the timing in response to the knock, and the whole thing would fall on its face. The work-around was a TBI unit & controller from a Big Block.

But the last engine I built was in 1992, and I've not been into engine mechanics in 30 years. So in a broader sense, what I'm asking is, do these motors still work on those principles? "Nitrous" is just French for "more air", and if we introduced some into the intake of one of these engines, would it try to adapt, or would it just decide something is outside parameters and shut down?

This old timer build a 6-71 blown 350 for my CJ5 in the late 80’s and a B&M blown 454 (low 8lbs boost) for my V-drive Sanger in the early 90’s. Nothing in ~30 years also. This old guy is a tech idiot. ( heck, I don’t even know how to post a picture)

 

[Retrograde]

Give him a break— he didn’t ask “ what Carb should I get?” Don’t think I will ever forget that one.

I remember that. Actually, that was an interesting question... I was going to suggest an 800 CFM Carter AFB with mechanical secondaries. You could re-configure the secondaries to open up with a solenoid wired into the VVT circuit. Talk about a kick in the ass...

Kids these days don't even know what 6-71 means. I weep for the future.

 

[2nd 392]

I remember that. Actually, that was an interesting question... I was going to suggest an 800 CFM Carter AFB with mechanical secondaries. You could re-configure the secondaries to open up with a solenoid wired into the VVT circuit. Talk about a kick in the ass...

I ran two Competition Series 750 Carters because they fit inline on the 6-71 , Holleys had to be mounted sideways. Great Carbs!!! And Yes- the funniest thread ever, I suggested he also upgrade his ignition with points and a condenser.

 

[Retrograde]

I ran two Competition Series 750 Carters because they fit inline on the 6-71 , Holleys had to be mounted sideways. Great Carbs!!! And Yes- the funniest thread ever, I suggested he also upgrade his ignition with points and a condenser.

Sounds like a thing of beauty. You should learn how to post pics.

 

[BDinTX]

Wasn’t it the early 2000 Camaros/Firebirds you could inject nitrous in front of the MAF sensor and the ECM would increase fuel to account for the additional O2?
Feel like I read about that in Hot Rod magazine or something.

 

[2nd 392]

Sounds like a thing of beauty. You should learn how to post pics.

The latest generation Whipples are much more efficient, run much cooler and are low profile. But Nothing is More In Your Face With Power than a huge old GMC blower and carburetors sticking ~a foot out of the hood. ? Edit— Fortunately 392’s have weak, high compression, short skirt pistons. Whipple is only one hour south of me and does in house installs

 

[Retrograde]

The latest generation Whipples are much more efficient, run much cooler and are low profile. But Nothing is More In Your Face With Power than a huge old GMC blower and carburetors sticking ~a foot out of the hood. ? Edit— Fortunately 392’s have weak, high compression, short skirt pistons. Whipple is only one hour south of me and does in house installs

6-71 Jeep pr0n:

 

[Retrograde]

Wasn’t it the early 2000 Camaros/Firebirds you could inject nitrous in front of the MAF sensor and the ECM would increase fuel to account for the additional O2?
Feel like I read about that in Hot Rod magazine or something.

I've seen that discused. Apparently it's pretty common to spray in front of the MAF on the LS1 engines, but... one of the more interesting techniques I've seen is to spray after the MAF, and hack the IAT table in the PCM:

"The IAT trick essentially gives you two separate tunes. The PCM includes tables that modify spark advance and fuel enrichment in response to changes in intake air temperature. We take advantage of the fact that the range of these tables extends beyond normal operating temperatures and therefore parts of the tables are normally unused. We can modify the IAT tables in these normally unused areas to reduce timing and add fuel as needed during nitrous injection. When nitrous is activated, a relay in the IAT sensor circuit, forces the PCM to read a false temperature that falls in the modified areas of the IAT tables. Normally, intake air temperature is measured by a thermistor (IAT sensor) in the mass airflow sensor (MAF). When nitrous oxide is activated, a relay switches a fixed 300 ohm resistor into the IAT circuit in place of the thermistor. This forces the PCM to read a temperature of approximately 85 degrees Centigrade. The modified table areas then take over. The highest true intake air temperature I’ve seen is 59 degrees C, well outside the modified table areas. When nitrous is disabled the modified areas of the IAT tables have no effect and the normal timing and PE tables are used."

Link: https://ls1tech.com/forums/nitrous-oxide/1741872-most-you-ve-sprayed-front-maf.html

Hmmm...

But again, that's 20-year-old tech. I have no idea if our engines can be similarly hacked.

 

[2nd 392]

6-71 Jeep pr0n:

Hmmm- I could barely fit a 2” belt and put an electric fan in front of the radiator. Their engine is lower, my rear driveshaft wasn’t that short and I was running the heavier wagon/truck TC & a Muncie and mine was a short 63. Interesting ? (I think that was a stretch, but not sure) Oh yea— 50 state 392 Whipple only 6 lbs boost, performance model a whopping 8 lbs, pathetic. But that was a few years ago when I checked for the GC, new generation ones might be a little better, but same sh*tty pistons. Edit-The AMC ones stretched for their I-6 would account for the engine room, and their trans/TC possibility longer than my Muncie/Willys accounting for the short driveshaft. My old memory still works but is getting slower.? It clearly doesn’t have a “Willys” tailgate and does have a newer windshield.

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