Bad Dyno Numbers ~~~ HELP PLS !

WHats up guys.

Took my car to the dyno last night, got a diablo chip along with the run.. Car dynoed at 368 rwhp and 400 lb of torque @ 4700 rpm with major belt slippage.. The funny thing is before I took it to this guy when I had no chip in my car my car hit 420 rwhp @ 5k rpm, with belt slippage.. I wish I could post the chart to show you guys what it looks like but I'll do my best to explain it.. Basically we set the timing to 10 degres at Idle.. Fuel pressure was 11.1 .. He adjusted everything and I cant remember what the timing was at the end, but if you guys could post your numbers along with how they tuned it that would be great.. Also give me ur imput on what you guys think I should have got and what I could do to get to my goal which is 480-500 RWHP ... Thanks guys !

My combo consist :

331, sportsman block 8.8.1 compression all forged internals
185 AFR heads
crower cam 155122- (could be the problem)
1.7 cobra r.r
trick flow intake
vortech v2-sq stock pulley created 8lbs of boost
Power Pipe
80mm PRO-M meter
75mm accufab throttle body
42lb injectors
255lb Walpro Fuel pump
Vortech inline pump 190lb ( I believe )
A/C Eliminator
Smog Pump Eliminator
Denso spark plugs
BBK Long Tube headers
Dr.Gas X-pipe - No Cats
Sportsman Spintech Exhaust
Stock T-5 - could also be robbing me from making more power

I think your combo should be making 500rwhp minimum and realistically 550 rwhp. My Real Street car with a 306 makes around 550 rwhp. Kurgan Motorsports tuned my PMS for me.

Why haven't you done anything about the belt slipping?

That T5 is not robbing your power.

Havent done anything for the belt slippage yet.. Any ideas ? After last night, I think im stepping up to a 10-rib system.. Probably gonna put a 2.95 pulley set up on my S-Trim.. Since I only made 8lbs of boost with the 3.33, Im thinking the 2.95 should put me around 12lbs of boost or so ?? Not sure though..

Do you have your dyno sheet by any chance ? What was ur fuel/air ratio at ? Do you think the belt is the only thing stopping me from my goal ? I mean, my buddies 302 with just a novi made around 340 at the wheels.. I have a 331 with a s trim and im only making 361 rwhp.. Thats TERRIBLE !! All that money and have yet to see the power it should make..

Any ideas are very much appreciated !!

Thank you !!!!

Tighten the belt a lot more. I used to think my belt was tight, but I later found out that the belt tightness makes a world of difference. I tried out an S-trim on my motor and it made 18 lbs of boost with a 6.87/3.33 pulleys at 7700 rpm.

Well yea sorry to say those #'s are bad.

But man you have a nice soild setup, like RSNoiv said min 500hp. Once you do figure out your problem more than likey you will run into another. You need bigger injectors, and fuel rail and lines.

My S-trim 302 TFS heads, Holley SysteMax2 intake, B-31 cam, AOD 12psi dynoed at 474hp with 110 race gas, PMS tuned, and come to find out later my timing was way high 32 degrees total.


Brandon

I dont think I need bigger injectors to get 450-500 rwhp.. Im just a little curious to why the guy stopped the pull at 4800 rpm.. I mean regardless if the belt was slipping my motor alone could have put out more.. I honestly think it was the tuner.. Whats ur guys fuel pressure set at ? I think If I richen it up a little and take care of the belt slippage issue I should be good to go.. What do you guys think ?

Your injectors will be close to being maxed out at 500 rwhp, unless you are using an FMU. This should be easy to tell on the dyno though.

I typically run a static fuel pressure of 50psi on a boost sensitive regulator. We shoot for around 11.5 air to fuel ratio.

What area are you in?

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Originally Posted by 331stroker

WHats up guys.

Took my car to the dyno last night, got a diablo chip along with the run.. Car dynoed at 368 rwhp and 400 lb of torque @ 4700 rpm with major belt slippage.. The funny thing is before I took it to this guy when I had no chip in my car my car hit 420 rwhp @ 5k rpm, with belt slippage.. I wish I could post the chart to show you guys what it looks like but I'll do my best to explain it.. Basically we set the timing to 10 degres at Idle.. Fuel pressure was 11.1 .. He adjusted everything and I cant remember what the timing was at the end, but if you guys could post your numbers along with how they tuned it that would be great.. Also give me ur imput on what you guys think I should have got and what I could do to get to my goal which is 480-500 RWHP ... Thanks guys !

My combo consist :

331, sportsman block 8.8.1 compression all forged internals
185 AFR heads
crower cam 155122- (could be the problem)
1.7 cobra r.r
trick flow intake
vortech v2-sq stock pulley created 8lbs of boost
Power Pipe
80mm PRO-M meter
75mm accufab throttle body
42lb injectors
255lb Walpro Fuel pump
Vortech inline pump 190lb ( I believe )
A/C Eliminator
Smog Pump Eliminator
Denso spark plugs
BBK Long Tube headers
Dr.Gas X-pipe - No Cats
Sportsman Spintech Exhaust
Stock T-5 - could also be robbing me from making more power

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chris is right, this combo is good for 525-550rwhp with good gas... those injectors, if put at 50lbs base FP, will support 550rwhp..

Right now the guy set my fuel pressure at the turn of the key to be around 35lbs .. When we got into WOT I believe the fuel pressure was at 42lbs or so.. I thought that was low but the guy said he wanted to be conservative.. Whats ur guys timing at from the turn of the key to when u get to WOT ?

They mean run your base fuel pressure at 50psi at idle. With the car running pull the vacuum line off the fuel regulator and plug the hose. Turn the regulator untill the gauge says 50psi. Then re-install the vacuum hose on the fuel regulator and your set. Watch your fuel pressure to make sure it still raises under boost.

good luck.

Hey 86merc, how much boost are you running to reach those numbers ?
How come so much FP at idle ? How much boost do you go under when ur at WOT ?

I saw about 13-14#. I have a little belt slippage though. Timming was at 18 degrees for pump gas.

The higher fuel pressure will force the injector to flow more fuel. When it can flow more fuel it will be able to support more HP. *Side note: This is not always true. If the fuel system is not up to the task the fuel pressure will not climb with the boost referance. That would be a bad thing so make sure to watch it too.*

The added fuel pressure might require a little tweaking on the tune to get the a/f ratio right again.

U have an S trim right ? If so are you using the stokck pulley setup ?

It is a s-trim with a 3.33" blower pulley with a 8" crank pulley.

Damn thats what the v2-sq came with and u made that much boost ??? Chit ! Whats ur hole combo ?

The V-1 S-trim has a 6.87" crank pulley. I am sure the V2 has a simular size too. The 8" is a upgraded Renegade pulley.

The hole combo is too much too list. haha Here are some of the highlights.....

331, AFR185's, ported truck lower intake with a "Civil Wars" box upper, 55# injectors, 80mm Pro-M, 1 5/8" shorty headers, 2 1/2" full exhaust, TKO, and a 9" rear end with 3.70 gears. The cam is a Lunati (int/ext) 232/242 @50 and .544/.560 with 114 seperation.

A upgrade to a Holley Systemax II intake and Dart block are the plans for this winter. I would be happy to see 550rwhp on pump gas all said and done.

Nice combo.. Sounds mean... What do you run in the 1/4 ?

I made 18 with an SQ 6.87/3.33. Of course that was a 7700 rpm.

Quote:

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Originally Posted by 86merc

The V-1 S-trim has a 6.87" crank pulley. I am sure the V2 has a simular size too. The 8" is a upgraded Renegade pulley.

The hole combo is too much too list. haha Here are some of the highlights.....

331, AFR185's, ported truck lower intake with a "Civil Wars" box upper, 55# injectors, 80mm Pro-M, 1 5/8" shorty headers, 2 1/2" full exhaust, TKO, and a 9" rear end with 3.70 gears. The cam is a Lunati (int/ext) 232/242 @50 and .544/.560 with 114 seperation.

A upgrade to a Holley Systemax II intake and Dart block are the plans for this winter. I would be happy to see 550rwhp on pump gas all said and done.

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hi mike....

what was the injector duty cycle on your car, i forgot?? and what did i set the base fp at??

thanks

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Originally Posted by flyin_hawaiin

hi mike....

what was the injector duty cycle on your car, i forgot?? and what did i set the base fp at??

thanks

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Hey Bob,

The base fuel pressure was at 50psi. We raised it early on in the runs from 40psi when the duty cycle got high. I would have to take a look at the data logger for the last pass to be sure. I do know the duty cycle was over 95% at 6000rpm and 14# of boost.

331stroker- With the FMS extender and a piss poor suspension the car went 11.86 @ 124.49 with a 1.96 60' on a nitto drag radial. I have not run the car since the upgrade to the PMS. New suspension is going on the car right now. I am hoping for 10's on pump gas in full street trim.

Sounds good ! Im thinking about pulling out the chip the guy gave me and going to a new dyno tuner.. I mean, my first gear and second gear has NO power at all.. It feels like my stock 302, the guy tuned it soo when Im at WOT the car gets 42lbs of FP at the most, and that was at WOT in Fourth gear.. Every other gear he set it up so that its running 35 lbs .. You guys thnk thats the cuase of the huge lack of power in the lower RPM's ?

Quote:

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Originally Posted by 331stroker

Sounds good ! Im thinking about pulling out the chip the guy gave me and going to a new dyno tuner.. I mean, my first gear and second gear has NO power at all.. It feels like my stock 302, the guy tuned it soo when Im at WOT the car gets 42lbs of FP at the most, and that was at WOT in Fourth gear.. Every other gear he set it up so that its running 35 lbs .. You guys thnk thats the cuase of the huge lack of power in the lower RPM's ?

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where ya located?

San Francisco

Hey 86Merc, what spark plugs do you got in ur ride ?

UUUUMMMMMMMMMM.....hahahaha Its been so long sience I touched the car I don't remeamber. Damn winter!

I know I have used Champion RC9YC and Autolite 3923. I think the autolites are in the car. I plan to change them to AR3923 (cut back plug) in the spring.

see where I live, right now its pretty warm.. So Im thinking about changin out my plugs and putting on that 8" crank pulley..

So you think I should run my FP at 50lbs at Idle ? How about WOT, how much FP should I peak at ? How about ur timing ? Let me know how ur's was set up, so next time I go if he tries to pull a slick move ill jus do the adjustments myself..

Appreciate it Merc ~!!

I would talk to the guy that burned the chip for you first. You lost 52hp after he burned the chip right? Why? I would find out what he did to loose power. Or see if he will retune and burn the chip. I just hope he didn't hurt the motor.

You caould find another dealer to retune the car and make the nessassary changes. It will cost you more money but it might be worth it. Something is wrong as the car sits.

To save money you could pull the chip out and run strait timming at 17-18 degrees. The 50psi base pressure would be a good place to start with. I would HIGHLY recommend getting a wide band on the car to see what A/F ratio you would have. I would bet it will be lean with out a chip or a tuning devise. You might have to keep raising the fuel pressure untill the A/F ratio is OK.

The fuel pressure should raise 1:1 with a standard regulator. If the fuel pressure does not climb when your in boost you will have problems.

Shoot for about 17-18 degrees of timming at max boost and a A/F ratio of 11.5-12:1 to start with.

I hope the original tuner makes good and fixes the tune in the chip or at least find out whats wrong. Good luck man.

So i just got off the phone with my tuner, he said that he thinks the car didnt hit my old mark at 5k rpm cuz of the slippage issue.. From 3700 rpm you can see the line start to create divets until he stopped the pull.. That means slippage im assuming since before that its practically a straight line.. But the torque line starts the divits @ like 2500 rpm.. Why is that ? But im hoping that the cause of the 50+ was from the belt slippage. I told him about how the car feels slower at the lower rpm's and he thinks he richen it up too much an to lean it out, does that sound right ?

Im going to install the 8" on Sat morning then head over there in the afternoon and hopefully come back with a better story/numbers...

Please give me some ideas or things to check or do before, thanks for everything guys !

Merc ~~ Thank you !

Well thats cool he is willing to look into it. I wouldn't think he would have let the car leave in that state. Hopefully he will get you all strait again.

Bring tools to adjust the fuel pressure and the tension on the belt. Using a torque wrench tighten the belt to 175# or more using the stock Vortech adjuster. For dyno time you should be OK. (Renegade guys run way more tension on their belts). The belt will stretch too, so make sure to check it in between runs. Then loosen it up to 125# when your done tuning. You do not want all that pressure on the belt all the time.

Good luck man!

Quote:

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Originally Posted by 86merc

I would talk to the guy that burned the chip for you first. You lost 52hp after he burned the chip right? Why? I would find out what he did to loose power. Or see if he will retune and burn the chip. I just hope he didn't hurt the motor.

You caould find another dealer to retune the car and make the nessassary changes. It will cost you more money but it might be worth it. Something is wrong as the car sits.

To save money you could pull the chip out and run strait timming at 17-18 degrees. The 50psi base pressure would be a good place to start with. I would HIGHLY recommend getting a wide band on the car to see what A/F ratio you would have. I would bet it will be lean with out a chip or a tuning devise. You might have to keep raising the fuel pressure untill the A/F ratio is OK.

The fuel pressure should raise 1:1 with a standard regulator. If the fuel pressure does not climb when your in boost you will have problems.

Shoot for about 17-18 degrees of timming at max boost and a A/F ratio of 11.5-12:1 to start with.

I hope the original tuner makes good and fixes the tune in the chip or at least find out whats wrong. Good luck man.

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I do have an A/F ratio gauge but its from Autometer an all it does is jump around when I push in the gas.. At Idle thogh it holds steady, is that what your talking about ?

p.s.

He is using a wideband o2 when he is tuning the car right?

Ohh hey one more question.. What size or where did you get ur belt from when up uped the crank pulley ?

I dont think he is.. He didnt install a new 02 sensor on my car, the only tools he used was his labtop and his dyno machine.. Should I ask him about that ? If so what should I ask him ?

I got it at CarQuest. Off the top of my head I think it was 54". You might want to make another thread to find out for sure. Of call Vortech, they will hook you up.

If I put around 3-5 gallons of 114 octane and the rest 91 octane, will that help me out when I get under 12-14lbs of boost non intercooled ? I know they say not to run that much boost without an intercooler but im afriad with the 8" that I just purchased that its going to make that much boost.. Hopefully its around 10-12 lbs of boost and nothing more.. But how can you tell, u know.. So Im thinking that if I mix both octane's together that, that will compensate for intercooler, is this logic wrong ?

Do you always plan on running mix of 93 and race gas? If not I would tune the car just on 93. If you tune it for a mix and stop running it you can damage the motor.

I have a simular cambo that I see 14# out of. With a safe A/F ratio and timming you should be fine.

The tune is what will make power and keep it reliable. I just hope your tuner knows what he is doing.

Quote:

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Originally Posted by 86merc

Do you always plan on running mix of 93 and race gas? If not I would tune the car just on 93. If you tune it for a mix and stop running it you can damage the motor.

I have a simular cambo that I see 14# out of. With a safe A/F ratio and timming you should be fine.

The tune is what will make power and keep it reliable. I just hope your tuner knows what he is doing.

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god knows yours doesnt.. hahahah

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Originally Posted by flyin_hawaiin

god knows yours doesnt.. hahahah

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HAHAHAHA.....True! I was surprised he knew how to start the car let alone tune the car. :freaks: LOL

Well out here in CA, the octane is a whooping 91 !! BS !! Thats why I figure If I mix it or put about 3-5 gallons of 114 or 110 whatever it is that it'll mix an become higher then 91.. But I know what you mean about tuning the car to whatever gas you have in it.. If there was 93 octane I would be good to go..

Belt slippage should cause the power curve to flatten out, you mentioned "divots" which sounds more like your spark may be blowing out, or if the "divots" in the curve come in at 5500 to 6000 it may be valve float.