Nicky,

I looked at a Zex system for the Charger and it looks quality. For $550 you get a 10 lb bottle and all the fixings for a two hour rendezous with the 12 second clock. Adjustable from 75 to 125 HP. And like you said, only works at WOT and has computerized management system, so you don't lean out. The ricers sure like this stuff...

[sm=confused06.gif] Maybe since it is computer controlled, it wouldn't be such a bad idea...



MN

 

I wouldn't run a 125shot thats like playing with fire on a stock motor. But with the modd's I know you have you should be in the low 13's as long as there is not too much tire spin off the line. And you'll get away with a 125shot but I would only do it once for a nice 12second run.

 

Thanks, Nicky,

Of course, I was guessing on the times, but an extra 75 or 100 in an 8 cylinder shouldn't hurt much -- once in a while at full throttle, like you say. I am very interested in this since as very few times a person would actually use it, it would give a nice punch. I can't believe what the ricers put into their engines and they still run...

I plan on headers, then Zex's Charger set up. Start with 75, get used to it, and move up abit. Running a 4,000 pound car into the 13's is a pretty good feat -- 12's would be be wilder, but if I want to get nuts, I should just buy another muscle car .

Heck, there is always someone faster and I really love the Daytona for just cruisin' and trips...

Thanks for the info.



MN

 

You should look into ported heads you could run a 125shot everytime you spray if you want but they are expensive. And with headers, chip, cai, and a 75shot you might be able to pull off a 13flat cause you would be close to 400HP, with a 125shot you would be deep into the 12's. And you would surprise alot of srt-8 owners. Also where did you find a zex system for the chargers?

 

Nicky,

Here's is where I found the Charger system: http://estore.websitepros.com/802805/Detail.bok?no=775

I also read that the stock 5.7 heads flow very well (from Hot Rod magazine). I have wanted to just swap a set of 6.1s onto the 5.7 block. Still thinking of that one, EXCEPT, I would have to put on 6.1 headers, not 5.7 headers... so I am still deliberating what I really want to do.



MN

 

Also with the nitrous system yo should get a purge kit as well. And can you PM me on where I can get these 6.1 parts.

 

Couple of cautionary notes to offer the NOS user. Call it weaknesses in the 5.7

The unit has slipper style pistons, designed by race engineers, and has a weight of just 413 grams. That makes the Piston heads light.. hard.. but vulnerable to burn-through. The Piston has a top ring of hard anodized that acts as a heat barrier, which spaced a mere 3 mm below the top of the piston, and directly behind that a resevoir grove cut to reduce pressure between the top and second ring. In another words this top ring is a substantial vulnerable point.

The 5.7 is regulated to 5500 rpm for a reason. Many of the counterweights and dampers on conventional performance engines are designed out for the sake of weight and unit cost. The crank has innerweights that are engineer to be offset by the exact weight of the piston & rods. The Serpentine belt on your unit has been designed to act as a torsional damper. Again for weight, cap bolts are used instead of through bolts. The stock Cam is partially hollow & has oversided journals and lobes to minimize the side loading on the roller lifters, All this to say that the unit has had pressures and stresses carefully engineer out of it to balance weight/performance/cost.

For the 6.1 SRT 8 & its increase of 3 MM head size, 20% in RPM, 23% increase in HP, and 13% in overall available airflow DCX has added oil squirters under the piston and a pressure relief valve off the pump, crankshaft dampers, billeted steel camshaft, premium valve springs and additional valve train dampers. Looks like DCX wanted to do abit more to the 6.1 due to likely stresses, possible in the stock 5.7.

You decide for yourself, but just understanding the differences between the 5.7 & the 6.1 gives me some clues to possible weaknesses in my unit should I take performance up substantially..... as with 100 shot of NOS, forced air injection, etc

Good luck out there.

 

Daytona RT,

That is nice you write a technical piece, however, what are you trying to say?

If I put on a 100 shot of wet NOS, I'll end up with a solid piece of metal? I know the 5.7 isn't a full race piece, but is it good enough to handle a 100 or 125 wet shot?

MN

 

MnBoy,

I've been *unofficially* assured that a 1/4 mile 100 shot will never be a problem for the stock 5.7. But.. with the lack of even flow through manifold, the unit *May* on multiple passes or extensive use, cause the intake to detonate, valves & piston rings to fail.

Purge kit alone will not avoid this potential. The us of duel Stage 100 & 225 shots, multiple passes or extensive use of the milk bottle, anyone that knows the forces, will tell you that even a tight engine is vulnerable to major failure. Like anything else, gross excess is the recipe to catastrophy.

The rings vulnerability is real. I'm told that the 6.1 piston heads and ring materials are substantially improved. I cannot tell you to what degree or under what stresses the top ring might fail, but two reports I've read recently mark the engineered set of top ring, pressure cutout and 2nd ring as a point of vulnerability for the unit under very high performance.

My only reason for the research and composition of this information is to have/give a better understanding of the 5.7 unit, it potential for expanded performance and the real issues that need to be addressed for Mod III developments. I passed the information only to give the cautionary note to those that may not otherwise know what and why the 5.7 was engineered to do.

I myself, am having Kelly @ heat performance develop the project for the Comp Cam, 6.1 stage II heads and 6.1 manifold. duel 80 Mill throttle body & the two stage NOS system to max with a 125 shot. So with that said, until I knew the issues to cope with, I couldn't make the decision to abandon the 5.7 topdeck & expand the exhaust to 2.75".

Pssst.. The 5.7 single turbo is available and staggeringly strong with the topdeck retro. Breakin the 12 second floor is an attainable goal, but at a daunting cost.

Again, my hope is that this information helps someone somewhere. Be safe out there.

 

Daytona RT,

I read the Hot Rod magazine in-depth report on the 5.7 just after I bought my Daytona. They loved the motor and especially the heads. The way the spark plugs and valves are configured, it allows much better air flow just from it's configuration. They liked the pistons, etc, etc, etc, but warned that if too much HP was being forced, the crankshaft wanted to climb out and leave. However, after their toying around, they were getting impressive HP on the dyno.

As you said, Dodge engineered the problems out of the 6.1, so that engine will tolerate more and produce more -- as you already know, in just 33 cubic inches, they forced out 75 more HP.

I have been egged on by my boys and their ricer group to try wet NOS on my Daytona. Of course, in my old school thinking, headers would go on first and free up the exhuast, but I'm afraid of re-awaking the dreaded DRONE dragon. They think a 100 shot would be plenty and with 8 cylinders dividing up the gas and extra fuel, they should tolerate it well. I will approach this idea very carefully (ie, probably let someone else be the guinea pig ). But that ZEX system, with its computer controlled system, looks idiot proof...

You provided interesting reading.



MN