500 rwhp without intercooler posible?

I would like to know if that is possible safely without an intercooler... I am planning to run 9psi... I am doing right now 392 with lack of fuel and a crappy cam... Cam was changed already and 9 psi is next...

I would love to get to 500rwhp without the need of an aftercooler.

Is it possible or most likely or impossible?

THanks

500rwhp without an after/inter cooler is easily attainable. (IMO just not possible with your current compressor)

Well, if your not goin to use an after cooler are goin to at least run some kind of cooling agent like a water/alky injection or n20?.

My car right now is running 18+ psi of non-intercooled boost, according to the dyno guys, at around 6000rpm, and once we get the fuel problems solved, it should go till around 6700 rpm. We are also putting on a larger pulley to bring the boost down to around 13 psi so we don't have to remove nearly as much timing, and it should still yeild the same hp results as the 18 psi with a bunch of timing removed. Once everything is sorted out, we expect it to make in the neighborhood of 480-500rwhp. This is done with a t-trim and no cooling method of any kind. Obviously cooling of some sort would be very beneficial in my case, and I am looking into it, but this is how I bought the car. My point in all of this is that with a proper tune, the proper engine components, and running high octane pump gas, you can obtain 500rwhp without an intercooler. btw, my engine is a 355 with forged internals, a custom ground 'blower' cam, and a few other goodies.

i've been tossing around the idea of single turbo or a 9# vortech s trim no inter/after cooler, some bolt up stage 1 heads real wild blower cam plus boltons. could i see 500rwhp with that setup? thanks



doug

Well.. no.. I got 447 yesterday... :mad:

I did some major mods like changing to an S-trim, fuel pump, bigger injectors, LTs!!! and a better cam...

All I gained was 50rwhp bumping from 393 to 447

Originally posted by The Highlander
Well.. no.. I got 447 yesterday... :mad:

I did some major mods like changing to an S-trim, fuel pump, bigger injectors, LTs!!! and a better cam...

All I gained was 50rwhp bumping from 393 to 447

F-bud: what (exactly) was changed? That would help in figuring out if that's a reasonable hp gain or not. In terms of analyzing what is going on and if that's really what your combo is capable of, that's tough to do without a lot more data. But just a shot in the dark: it is very common with an LT1 is to have the computer pulling huge amounts of timing. I finally disabled the knock sensor on mine after being unable to deal with the false knock. It was pulling 10-12 degrees of timing and I was losing ~50rwhp as a result.

Rich Krause

Ok... here it goes

I changed the supercharger.. from the paxton sn93 to the vortech s-trim

I am seeing the same IATs at 9psi than at 4.5 the other time.

I changed from the shorties 1 5/8 to the 1 3/4 2300º ceramic coated hooker and a nice y-pipe...

I did the upgrade to a 255lph in tank pump GSS340 with the racetronix harness...

and I did change from teh 215/220 533"/544" CAM TO

224/236 114 lsa XE 3300 series

I was running total advance as seen on the logger with 36 and retarding 2º/boost... If I go down on the retard I will get some spark retard at around 4krpm and no more spark retard after that...

I dont get it though... but maybe my problem is timing...

I was hoping to reach the 500rwhp mark with it and I am a bit dissapointed to get only 450.

Street renegade cars make over 800rwhp with no intercooler so yes it is possible, even with 310cid:)

Originally posted by The Highlander
Ok... here it goes

I changed the supercharger.. from the paxton sn93 to the vortech s-trim

I am seeing the same IATs at 9psi than at 4.5 the other time.

I changed from the shorties 1 5/8 to the 1 3/4 2300º ceramic coated hooker and a nice y-pipe...

I did the upgrade to a 255lph in tank pump GSS340 with the racetronix harness...

and I did change from teh 215/220 533"/544" CAM TO

224/236 114 lsa XE 3300 series

I was running total advance as seen on the logger with 36 and retarding 2º/boost... If I go down on the retard I will get some spark retard at around 4krpm and no more spark retard after that...

I dont get it though... but maybe my problem is timing...

I was hoping to reach the 500rwhp mark with it and I am a bit dissapointed to get only 450.

Don't get me wrong, I am not saying it's is safe to run more timing (and I am also not saying it's not) but you do not have enough timing. You are running 18 degrees of timing. Somewhere around 30-32 should be optimal and I bet you would see another 40-50rwhp with that degree of timing. Put in some race gas and try it.

Rich Krause

I used to run 36º with my previous setup... I dont see a way of doing so now... I wish I could run 32!!! As a matter of fact.. My current goal is 25.

I mean.. with 9psi and 9:1 CR I think it is attainable.... So.. Why am I getting knock if I turn it up a bit???

I do think my valvetrain is a bit noisy but I do have the lt4km....

Dont get it

Check this run that I did today:

http://netdial.caribe.net/~highland/32deg.uni

or

http://netdial.caribe.net/~highland/32deg.zip

if you can check them out let me know


That tune seems lean but on the dyno I was getting 12.6 afr... and in that tune its showing 880mv more or less...

Let me know what I could do.. I will start by going even more conservative on the timing to TURN DOWN the msd dial and build up from there till I get 0 knock...

I have some race gas which I will try soon and go to the dyno again...

Originally posted by The Highlander
I used to run 36º with my previous setup... I dont see a way of doing so now... I wish I could run 32!!! As a matter of fact.. My current goal is 25.

I mean.. with 9psi and 9:1 CR I think it is attainable.... So.. Why am I getting knock if I turn it up a bit???

I do think my valvetrain is a bit noisy but I do have the lt4km....

Dont get it

Check this run that I did today:

http://netdial.caribe.net/~highland/32deg.uni

or

http://netdial.caribe.net/~highland/32deg.zip

if you can check them out let me know


That tune seems lean but on the dyno I was getting 12.6 afr... and in that tune its showing 880mv more or less...

Let me know what I could do.. I will start by going even more conservative on the timing to TURN DOWN the msd dial and build up from there till I get 0 knock...

I have some race gas which I will try soon and go to the dyno again...

If it's not too lean, with 9:1, your cam, and race gas you can run 30+ degrees with no problem. Put the race gas in and adjust the AF ratio to ~low 12's:1 range. Turn off the boost retard function and disable the knock sensor (in software). Start at 20 degrees and move up to 24 degrees. If it makes more hp go to 28, then advance by 2 degrees per run until the hp increase flattens off.

Back off a few degrees from where you get max hp with race gas then do a run with the KS activated and the fuel you will run on the street. That should put you in the ball park.

Rich Krause

Perfect.. that way I can determine if it is true or false knock.. this is the first time I encounter this sort of problem.. actually the knock on that run, if you saw it, wasn't there yesterday...

But the other question is... I should be running 30+ timing.. ok.. but... with 200F IATs?????? My idle IATs in a point where as high as 160... Something was not right... The other thing is.. I am seeing the same psi but on the scanner I am not seeing the same AFGS from the maf.. I maxed out my maf quite a few times and now I am not able to do that.. maybe I have a leak on my intake side of the supercharger that is making my car leaner...

Hmmm... After writing it.. I thought it, and I think it could be a possibility on why my blms are way lean now and not as lean yesterday... got to check...

burger made 540 rwhp w/ a 10 lb non intercooled s trim on the 355 that is going in my TA (along with another s trim).. so it can be done without a ton of boost too.

Originally posted by aram
burger made 540 rwhp w/ a 10 lb non intercooled s trim on the 355 that is going in my TA (along with another s trim).. so it can be done without a ton of boost too.

Do you have a way of knowing his IATs???

Let me know

Thanks

Highlander:
For my own curiosity,
What kind of injectors are you running? 50#?
What PSI of fuel are you currently running?

Thanks,

8 30# svo's
2 90#MSD's and 1 34.8 siemens (theese are on the superfuelers)

PSI should be 43

I have no problem with fuel as I have been able to get to lower than 10:1 AFR at 6krpm

Originally posted by The Highlander
8 30# svo's
2 90#MSD's and 1 34.8 siemens (theese are on the superfuelers)

PSI should be 43

I have no problem with fuel as I have been able to get to lower than 10:1 AFR at 6krpm

Good to know....I thougth that you might be running out of fuel with the Air fuel ratio going upto 12.6 to 1 but thats good to know that I shouldn't have any problems running the same Walboro pump and 50# injectors on the rail to achieve the same results as you are getting.

Thangs again,

I do have a lightly heavier cam though... I prefer the route of the 30s and superfueler because its easier to get better gas mileage...

As of right now I am doing about 7 mpg....

I will be changing to speed density today to see if it aids a bit of a problem that I might have with the intake... I was maxing out my maf in the beginning at 9psi and now the most I was getting was 441g/s so there may be some air comming via somewhere else rather than the MAF...

I will try and rich it up more and see if I can advance a bit more to get to the 500rwhp

Its possible.. did them today!!!!

501rwhp!!!


Now onto the bad news... the car doesn't feel as a 500rwhp car...


I raced my father on his z06 and I couldn't beat him..heck.. he has 360rwhp....

Damn

The gig??? Well.. I uninstalled one of my O2 sensors to install the wideband... and the car ran in open loop... hence how I tuned it... now.. the car is running in close loop and its not performing.. anyone got an idea??? Shouldn't the car run by tables??? It has happened to me twice with 2 different cars.. the car will not run the same in open loop as closed loop... WHY?

Out of curiosity again :D

Where you still only using your Walboro 255 intank pump only?
And did the car run lean at all while trying to achieve 501HP?

Thank,

I raced my father on his z06 and I couldn't beat him..heck.. he has 360rwhp....

Are you putting the power to the ground? In other words, have you done anything to the suspension? I ran door to door w/ a Z06 a half dozen times w/ just the Procharger, Metcos and ET Streets. :confused:

I was in third, I didn't want to race, I double clutched to 2nd and slipped... i had to let go... and started again and then missed 3rd.. but the car wasn't running quite as it should because:

To measure the AFR on the dyno I had to disconnect one my O2 sensors and the tunning was done in open loop.. on the street.. there was no tune, because the O2 come back in and the car is in closed loop and a different table is used. :(

I changed gasoline and finally was able to hit better timing with higher heat...

Another thing though.... I did the 501 with the car cooled down... IATs were 120 at full boost, as opposed to 487 when they were 170-180

Judging by your description of MAF readings and experience with open vs. closed loop, I'd say that you have an air leak after the MAF.

You see, the BLM will change to compensate for an air leak. These computers will adjust your WOT injector pulsewidth based on the BLM at part throttle. In other words, if your BLM is anything other than 128, then the computer is changing your fuel settings while at full throttle in closed loop.

You can either fix the leak or lock the BLM on 128 using LT1Edit or TunerCAT.

I had an exhaust leak that caused a similar condition in my car. My left BLM was 128, and right was 144.

Mike

I fixed that.,.. it was an air leak...

Now I have a huge problem!!!!

After 5400rpm the AFR will climb no matter what I do... am I maxing my injectors or is it that I after reaching the 471gps?

When I turn off my superfueler, my A/F ratio climbs after the MAF maxes out (about 5200 rpm). So, any additional fuel the engine needs after the MAF maxes is supplied by the superfueler.

Essentially, my superfueler does nothing until the boost passes 8 psi.

Either your superfueler isn't adjusted properly or your fuel pressure is dropping off.

Mike

Well... That remains to be seen.. my superfueler is set up to produce after 7psi...

I have it MAXED OUT at 9-10 psi!!!!

I have 2 90s and 1 34.8 which I will substitute for another 90.

Let me know what you think...

According to my calculations, your 8 - 30's, 1 - 35, and 2 - 90's will support over 600 rwhp easily, so you have enough injector.

If the superfueler is on max, then the 8 main injectors must not supplying their rated fuel flow. This could be due to either not enough fuel pressure, or the computer not telling them to increase pulse width. I can think of the following things to check/try:

1) Check the fuel pressure under boost at high rpm.

2) Check the tach wire to the superfueler to make sure it's hooked up.

3) If 1 and 2 are OK, then go into the computer using LT1Edit or TunerCAT and adjust the PE table upward where you're experiencing the lean condition. This will increase main injector pulse width and richen the mixture.

Mike

I will check the fuel pressure under boost.. I have a racetronix fuel pump with the harness I have the high pressure.. I have the fuel pressure set at 55psi... Any other suggestions??? I have a flatline at 12.5 but when I max out the maf it will go up no matter what.. I have the PE tables already at 50 with tunercat...

Let me know.. I have seen on datamaster 150% duty cycle :confused: anyways.. maybe the bigger injectors are not flowing what they need... when I had 393rwhp I had 3 34.8 siemens up top and they were maxed out...

Sounds like you need some 42's and to start adjusting your VE tables...

Jack :cool:
Racetronix

But as set earlier... shouldn't I have enough injectors to run 600rwhp?

I am barely getting to 500's

No matter how much I put up my PE tables after 5400 I will still get that change in slope in the AFR at the same spot...

I have set them at 50 with no change... other than that they are at the 30s.

I will try and up the pressure.. but... how much is enough and how much is it a good idea???

I thought that with the Superfueler i wouldn't need that much pressure...

I will up the pressure today when I get a break.. I will go racing tonight so to be safe it would be a good idea ;)

Based on your current DC you would need a ridiculous amount of FP to fix your problem. Keep in mind as you increase FP the pump's volume drops off. Too much FP makes it harder for your injectors to open thereby compounding your problem.

Best to use a 1:1 FPR and get a properly sized set of injectors based on your HP requirements and motor's RPM range so that at max RPM your DC is 80%.

Jack :cool:
Racetronix

I understand that...

I have the high pressure version of your pump, which I loved the harness :D

Anyways... I thought that the 30# would be good enough to 400 rwhp and the additional injectors could supply the additional 100HP to the wheels... THeyare 2 90s and one 34.8.

I haven't checked my fuel pressure but I think its dropping off right when I get to 5200rpm or so...

I thought that the GSS340 would supply easy to 500rwhp and with the harness could be even more...

Now my question is wether I am lacking fuel or not with this pump ??? I just installed it :( but I am sure it should be enough since rskrause has a bosch 255lp/h and a boost a pump and he makes 733rwhp.

I have an accel fuel pressure regulator and I thought that regular fuel pressure regulators acted as an FMU of some sort of 1:1

With 400# in injectors I shuold be able to do 600rwhp...

One possibility is that my MSD's are damaged or so since I took 2 from a car that damaged 2 of them and those where the healthy ones... I did checked them with an injector pulser and they worked fine...



Let me know...

Until we know for a fact that the FP is dropping we should reserve judgment. The HP system can easily support 500RWHP+ so I doubt it is a pump issue. If the FP is dropping then perhaps it is the signal going to your regulator? If you are running a base pressure of apx 60PSI+ manifold pressure rise (80+PSI) then perhaps you are causing a problem there. The supplemental fuel system you have will require large fuel volumes as much of the fuel is wetting the intake system instead of being fired directly at the valve. You are best off getting a properly sized set of injectors and a good ECM calibration. The money and time you will spend trying to get your external fueling system right is not worth it. I have seen all too many people fiddle non-stop with those fueling systems and at the end of the day the results are mediocre at best. They do not have the capacity to compensate for adverse engine conditions etc and run blind of the ECM’s sensor data.

Another solution to your MAF problem is to rescale the VE tables and use a two bar MAP sensor or change the MAF sensor (use a frequency divider or translator) and rescale your MAF tables. Unfortunately not too many tuners are willing or able to do this.

There are too many possible scenarios here and I do not have enough insight into your setup to be able to make an accurate diagnosis. Bottom line is that you should not be running a DC of 150% and excessive FP in order to achieve your desired A/F ratio.

Jack :cool:
Racetronix

Highlander: I need to step up to 72# injectors and I have my 50# MAD's for sale at $375 if it is interest.

Good luck.

I went to the dual in tank pump from Jack as well as a FAST - although I'm having my own problems with the WB O2 sensor.

I agree that my duty cycle shouldn't be what it is, but that is what datamaster reports...

I think that going to a 2 bar map sensor will make tunning harder as this will rescale everything to 1/2 including the VE tables... now instead of a 10kpa jump I will get a 20kpa jump so fueling will be done in larger chunks... that is why I haven't done the 2 bar map sensor... Actually... with a 2 bar map sensor I could precisely know what is my boost under what conditions since it is logged via Datamaster...

I do my own tunning and I haven't messed with rescaling my MAF tables, so my question regarding the maf tables is this... it it a PCM limitation or a MAF limitation? If it is a PCM Limitation you could trick the PCM on thingking that 471 is some higher value or so.

When I was on the dyno the guy controlling it told me that fuel pressure would go down... but I am that trustful of that FP gauge that I have installed because it fluctuates a lot, since it is not oil filled, and it is positioned right before the injectors. Now if memmory serves me well... the more flow the less pressure it will be? so... that means that pressure should fall slightly when those injectors are applied but should stay there no matter what...

I dont know my duty cycle but I know that it is commanding 27ms of injector time...

I know I have enough injector if all comes out well.. and I do like the system, although yes, it is blind, I like the fact that there is no additional fuel pressure per se and I control it accordingly to boost since I dont want too big injectors as it will hurt fuel economy more than what it is.. My best mileage has been 8mpg on the city, so putting bigger injectors would mean that I will need a pump station's hose soldered in my tank with a 2 mile long hose so I can drive around...
``

BTW I dont think its the pump either

8 mpg :eek:

I get about 13 -14 with my set up.

We have customers’ cars that are getting close to factory mileage with large injectors. A milligram of fuel is a milligram of fuel regardless if it takes a 2 or 4ms pulse width to get it. Injector sizing should not have a dramatic impact on your mileage provided you don't run them at lower than normal pressures which prevents proper atomization. My Buick runs 55's and I get 20+MPG on the highway w/o a lockup converter. Even the new SC Mustang has 42lb injectors (300KPa rated) in it from the factory which I believe runs at 400KPa. Rescaling the ECM's VE or MAF tables is not a big deal as the firmware interpolates between the table values. You must however edit the ECM control constants for items such as EGR control etc. We have one customer who makes 500RWHP with 42lb injectors, Racetronix LT1 pump system, 1:1 FPR, rescaled PCM on a supercharged non-intercooled 383 and he is static at just over 5500RPM.

Your FP should be stable and track the manifold pressure signal. If you boost drops because your motor is pulling more air than your blower can provide your FP will drop as well. I can think of MANY reasons as to why your FP would drop that are not related to a defective or undersized pump.

If you chose to keep your present fueling system the way it is then you are building your own brick wall and you will have to learn to be satisfied with the operational quirks it produces.

If you have trouble with the fuel system maintaining pressure after you have tested for a stable signal to your regulator please email support@racetronix.com and we will guide you through some basic steps in order to diagnose your problem

Good luck!
Jack :cool:
Racetronix

Im not building my own brick wall.. dont misunderstand my point... I will try out the 42lbs then and I will use the bar map sensor that I have laying around... (I first need some $ and then I will try that out. My brick wall is $ so I got to solve on what I have as of now... )

Another thing is that I didn't know it interpolated between fields... never thought it did... That is a big plus...

I like my setup for various reasons... I dont see extra fuel unless I get boost... It will cool down a bit the intake charge and that is a plus when you are non-intercooled and in an extreemely hot weather.

Its a better idea to use the bigger injectors and let the pcm control everything... It will see boost and I can log it and tune it with the logger then and on the dyno too... its better to mess with only one system than with a few, i know that.

I hope I install the fuel pressure gauge and I'll let you know.. then again.. I dont think its the fuel P.

I agree with Jack that the injector size doesn't affect gas mileage.

If you're running 55 psi fuel, it should definitely rise 1 to 1 with boost pressure. The regulator should "pinch" the fuel return line to make the pressure stay at the setpoint regardless of what the injectors are flowing.

Check your injector constant. 55 psi fuel pressure makes 30# injectors into 35.2#. If you didn't change your injector constant to 35.2, the computer will decrease pulse width to compensate.

You should have enough fuel system to run the power levels you describe. For some reason, though, the fuel isn't getting there. As you said, maybe some of your injectors aren't working.

Mike

I pulsed the injectors and they were ok (the 3 up top) but maybe they are not flowing what they are supposed..

I should have more than enough... I was just getting the jump up when the MAF hit 471