383 rwhp, stock hx35, tons of fuel, what gives???

Nick,

Sorry man... I just saw this thread. I will try to post up the graph tonight.

Chris
 
Hammer said:
Nick...
You can have all the fuel you want,but,if you can not get on top of the charger to utilize it all your doing is making smoke and making your wallet beg for mercy.You will never see more than the boost your seeing due to the way to large exhaust housing.At 34psi with a 21cm exhaust housing your about the end of your rope.If you had used a 16cm it would net you around 40lbs and may shove you towards 400 closer.

All of your mods in your signature shows me your looking for full on smoke effect instead of tuning for power.With a 12v you need to have a balance of air and fuel to make the power you want down low without having to much to kill it on the bottom.You overfuel a 12v down low and not have enough charger to recover and your HP numbers suffer and torque will be made late in the run.Remember a hard hitting 12v on a dyno will make max power not far from where it made power from Cummins(2300-2600rpm)and if you can get the charger lit early to make power sooner torque goes up substantially.

Your trucks signature shows me the timing is good,injectors will work if the tips spray hit the bowl,A plate to control low end fueling should be used and some afc work on the jet to tune the low end fuel application.Its not all about being maxed out on everything its about how you make mods work in your tune.I have seen many trucks make more power with less parts than your and know of a 98 stick truck that did 330/998 with a plate,16cm housing and some tuning.

Good Luck and keep hunting because I can tell you it doesn't get any easier the higher you go in HP when trying to perfect your tune for the next HP plateau,trust me on that one.........Andy
Click to expand...


Hammer, make no mistake about it, all of this fuel is not intended for the stock charger by any means. I have purchased, installed these parts, and tuned for the addition of a 66mm charger or twins. Tuning could be better suited to make better power on the hx35 i'm sure but that's not what I care about at this time. Fact is I can't make the charger go over 34psi even when rolling into it in OD on the street (not like Brett did on the dyno, seems he flat smashed it hence the smoke show!). I have tuned the afc by flipping the diaphram washers, grinding the foot 1/8" past the bottom portion and flat (not flat with the shaft but removing the protrusion at the top), installed the light spring from the TST kit, backed the preload screw out till it was flush with the interior of the housing, and the starwheel full forward. I don't want to purchase parts two and three times to suit my hx35 which will not be around at the end of the day so I do understand you can't just go throwing parts at something. What I don't understand is how come I'm not seeing the boost those with much much less fuel are seeing, that's the answer i'm looking for. It seems fingers are pointing toward the transmission!
 
Nick..
I am not sure what you missed but your problem,while it may have issues with the transmission,is exhaust housing related.I have already said that and you looked right beyond it to the rest of the post.The 21cm exhaust housing is to BIG for you to make big boost numbers with in a single combination.IF Joe D lost 7lbs of boost on a HX35 way back then when he switched from the 12cm to a ungated 16cm how much boost on top do you feel you lost with your 21cm?.

You aksed why it wouldn't fall over 400hp and I gave my opinion and that was based on what I have learned throughout the years of whipping on mine and what I have seen on dyno-jets out of 12v's,I didn't just pull it from thin air nor did I yank it out of my azz.When your making power that late in a run(your exact rpm said was 2850) and your torque(again you said 2600 rpm) its shows the lag pig that the charger has become.I have hundreds and hunderds of 12v dyno runs here and can show you proof that most ALL of the strongest running 12v's made max power before 2800 and were falling like bricks dropped from a building above 3000.Those trucks all made max torque from 2000-2400 and above that it also drops like a falling brick.

Yes guys do run these motors over 3grand but how many do that efficently I have questioned for years.When the sled pullers are in the outer orbit rpm zone its done for them to gain the wheelspeed neccessary to get the sled moving,not for efficency.They could care less about efficency all they want is wheelspeed.If you drag racing and do not tune for your truck for maximum efficency then you loose out in ET and top speed suffers.

You aked for an opinion,I gave you one you didn't like and I will stand by it.Unless you change the exhaust housing your numbers will stay low and not show the boost you feel you can not find.........Andy

P.S.-IF the 21cm housing was a good piece do you not feel that the 1st generation owners would not remove them and Ma Mopar would have left them on the subsequent built trucks in the first place?.
 
People use the 18.5cm housing from the 1st gen trucks and have good success with it and they see 40 or over psi hence my reply. I know mine's larger but not that much. Don't take it personal man, was just giving you an idea why I have so much fuel and a stock charger (at the moment):)

Have a look at this thread here where others (also with lots of 12 v experience) seem to think my issue is related to something else other then the 21cm housing.

http://www.competitiondiesel.com/forums/showthread.php?t=25228

Replies like #22 really make me think there is something going on. Further, B18B1LS1 made good power with an 18.5cm turbine housing on his hx35!
 
too much fuel is never a good thing

if you put out the fire with too much fuel before you start building boost you will never get the most power out of your ride. Fuel and air equal power on a 12 valve only if its properly tuned....

Rick
 
If you are pushing your hx35 over 35-38 psi then its pointless, u need a bigger turbo and tuning for a 66mm and twins is completely different, that turbo is rated for about 400 if your tranny is slipping and it sounds like it then your probably seeing the right hp for your combo.
 
after 35 psi my dodge would fall flat quit pulling as hard but it was fun to see how long the hx35 would take 55 psi
 
Nick...
I am at a loss here and confused with you.
There are many more than me telling you its charger related and there is no way you could even think of comparing the larger housing to the smaller one and make it perform the same.Reduced boost pressures mean lower drive pressures due to the size of the exhaust housing.You could never take a 21cm housing and expect it to manufacture the same boost levels that the charger made with the 12cm housing,its impossible as there is simply not enough air available in the HX35.IF your truck is properly tuned to make the best use of the turbo with the large housing your numbers will come up.You can not tune the truck for whats to come later and expect the same performance now out of what you have.:bang:bang........Andy

P.S.House....I figured you were trying to make a point and I think it was missed,LOL.
 
Well that does it, i'm going to do a test then! I'm going to swap on the 12cm stock housing and plug the waste gate to see what I end up with boost wise. If I get 40+ psi then I'll point the finger at the 21cm housing!
 
I didn't think it spooled to slow on the dyno for a 21cm housing, I just think theres to much fuel too early between the Dv's and Sticks he has, It was pretty difficult to back up on the dyno since it was so touchy.

Brett
 
dzlfarmboy said:
I didn't think it spooled to slow on the dyno for a 21cm housing, I just think theres to much fuel too early between the Dv's and Sticks he has, It was pretty difficult to back up on the dyno since it was so touchy.

Brett
Click to expand...

I'm going to slide the AFC back a little and see if that helps some of the touchyness Brett. Like you were saying, the rack/governor arm may have a little bit of room between the AFC foot at these lower throttle spots causing some of this herky jerkyness!
 
Dyno Graph

Here you go Nick...

Nick knows, but in case any of you are wondering, on the 2nd run the reflective tape fell off at around 2800rpm, that's why the reading stops. If i graph it over speed, the hp curve is nearly identical to the first run, just a little lower.
 

Attachments

  • Nick F.jpg
    Nick F.jpg
    73 KB · Views: 37
Last edited:
c-hawk said:
Here you go Nick...

Nick knows, but in case any of you are wondering, on the 2nd run the reflective tape fell off at around 2800rpm, that's why the reading stops. If i graph it over speed, the hp curve is nearly identical to the first run, just a little lower.
Click to expand...

Thanks Chris, going to reply to your email here soon!
 
Hammer said:
Nick..
I am not sure what you missed but your problem,while it may have issues with the transmission,is exhaust housing related.I have already said that and you looked right beyond it to the rest of the post.
Click to expand...

I guess what you say must never be questioned, huh? :bang

If the transmission isnt loading it up, then it is hard to make boost. Im sure an 18.5cm housing would help him out a little, but i dont feel like it is hurting him much myself.
 
I guess what you say must never be questioned, huh?
Click to expand...

Nope,
Thats where your wrong.
You must be another one of those who feel I pulled those facts from thin air or they were just made up.Its a proven fact when you change the exhaust housing for a larger one you will loose boost.In this article Mr.Donnelly states that a owner who swaps out the 12cm housing for the 16cm housing looses 4 lbs of boost.He then also states that to go to the 18.5cm housing you will loose an additional 2.5 lbs of boost more than the 16cm(so lets see here 4+2.5=6.5lbs of boost off of his originally stated 40lbs with a 12cm=33.5 lbs of boost,which would be close to what he stated when he began this thread).He also states that there is little or no difference between the 18.5 and 16 cm housings but many older truck owners swapped out the 21cm because of poor throttle response.Hmm,Lag,I think if you look at his sheet and see where the power and torque are made it shows that right away.


I'll leave you a link to the article to read,maybe you'll learn something......Andy

P.S.-Can you figure out what his boost loss will be from the 12cm since he has the 21cm exhaust housing??????.

http://www.turbodieselregister.com/featurearticles/AirFuelPower.htm
 
Hammer said:
Nope,
Thats where your wrong.
You must be another one of those who feel I pulled those facts from thin air or they were just made up.Its a proven fact when you change the exhaust housing for a larger one you will loose boost.In this article Mr.Donnelly states that a owner who swaps out the 12cm housing for the 16cm housing looses 4 lbs of boost.He then also states that to go to the 18.5cm housing you will loose an additional 2.5 lbs of boost more than the 16cm(so lets see here 4+2.5=6.5lbs of boost off of his originally stated 40lbs with a 12cm=33.5 lbs of boost,which would be close to what he stated when he began this thread).He also states that there is little or no difference between the 18.5 and 16 cm housings but many older truck owners swapped out the 21cm because of poor throttle response.Hmm,Lag,I think if you look at his sheet and see where the power and torque are made it shows that right away.


I'll leave you a link to the article to read,maybe you'll learn something......Andy

P.S.-Can you figure out what his boost loss will be from the 12cm since he has the 21cm exhaust housing??????.

http://www.turbodieselregister.com/featurearticles/AirFuelPower.htm
Click to expand...

First off, you should realize, a lot of boost does not mean a lot of power.

I have a 16cm housing on my truck. I lost about 4psi as you stated. I didnt lose any power. It is just a tick slower to spool, but hits much harder than the 12cm did. With a 21cm housing, you would lose about 9psi over a 12cm housing as a rough estimate.

If he is that overfueled, then a 12cm that has the wastegate line plugged will easily make 50psi. So even with the 21cm housing, he should be making I would say at least 40-41psi. I make 40psi on a non gated 16cm housing and My truck is not too hot. Stock 215 injectors, tst 191 delivery valves,a 0 plate, and 4k with 16* timing on a 160 pump. So If I can make 40psi on a 16cm housing with the fuel i have. He should still be making 40 psi or so on the 21cm housing since he has much more fuel than me.

Now, Im sure if he puts the 12cm back on, that he will be making 40psi, but IMO 40psi is still a low number on a 12cm housing with the gate shut with that much fuel.

Im still sticking to the transmission slipping being the main culprit.

Now, what part of that do you disagree with oh great one? :poke:

By the way. I didnt read your link*bdh*

Eric
 
You must log in or register to reply here.
Back
Top