norcalz28

iTrader: (13)

Wanted to get some input from the community and see where I might be coming up short with my build. The engine started out as a ZZZ crate engine, brand new zero miles. I left the shortblock alone and I installed new afr 180's, new comp xfi 268hr13, double roller chain, the stock base manifold, accel runners, and stock plenum were all ported and smoothed by lingenfelter to near super ram specs, accel 24lb injectors, 52mm bbk TB, accel plugs and 8.8 wires, new dizzy with cap and rotor.
Car runs strong, but the club had a dyno event this weekend and I was surprised to see that it made of best of 253rwhp. My old B2L motor made 214 rwhp stock, 228-230 rwhp with headers and full exhaust. I have a base tune in addition to the factory prom, but it seems to have made little difference. The car ran a best of 13.8 on the factory tune with the mods listed, and ran about the same over the weekend with very poor traction.
I don't doubt that I can get my et's down with some better tires, but I feel like my combo is just down on power to begin with. I realize there is some to be freed up through the tune, but I'm looking for honest opinions from the guys running similar combos. What type of numbers are you making? Thanks fellas

Will

Orr89RocZ

iTrader: (20)

Dont expect much on stock tune. Thats where i'd start

RyanJB

This is also where I'd start.
I had a similar situation when I did my build. Only hit 240 wheel, but the car ran extremely rich. I started tuning and leaning it out and it made a whole world of difference. I don't have dyno or track results yet, however the car idles much better, and has BLMs near 128 throughout the RPM range. It's certainly worth looking into.

norcalz28

iTrader: (13)

That's reassuring to hear. I have no doubt that the tune is the weak link. The car drives great, idles well with either eprom, so I figured I'd be in better shape than most. I will have to look into data logging at length so I can get this figured out. Thanks guys

Will

RyanJB

You have two different proms?
You didn't mention if you had the prom adjusted for the larger injectors. I bet it runs a bit rich, which would cost you a good bit of power.

norcalz28

iTrader: (13)

Yes I have the factory eprom, which the car ran 13.8 with, and a custom tune for the larger injectors, fan temp etc, best of 13.9 with poor traction. I am running 45psi which the chip was calibrated for, but it no doubt needs more work

Orr89RocZ

iTrader: (20)

Mass air can run those mods ok enough for idle and driving. But wot could be way off

Kennerz

Find a good tuner or learn to tune (obivious)

I would look into your fuel pump to make sure youre getting enough fuel. It may be falling off at some point or tired. And take another look at your exhaust set up, you may have something that is limiting your power somewhere (Small diameter tube, crappy muffler for performance,etc..). Transmission health? TV cable set properly. All the sensors set properly(TPS,IAC,Base timing correct). Bad or weak maf? TPI's are the most sensitive cars to set up right by far. EVERYTHING needs to be right on, or they will not perform, and there can be power left on the table from not checking the details..

When I put my TPI back together a few mothns ago, all the oversize runner gaskets I bought ((TPIS(better) & Felpro for Accel over size runners(worse)) were overhanging the port quite a bit to the point of where there would have been an obstruction. I port matched the gaskets (a lil Time consuming) and it made a very noticeable difference.

Just saying check everything you can think of, then research more and ask questions.

norcalz28

iTrader: (13)

There really aren't any local tuners that are willing to work on obd1 cars up this way anymore. I'll most likely start doing it myself, which is what I had wanted to do all along, just couldn't dedicate the time to it.

As far as the items you listed, the walbro 255 has only about 10k miles on it. Exhaust is hooker 2055's, carsound 3" cat, 3" single in/out flowmaster catback. Should be more than enough flow for the setup. Sensors are all calibrated, maf readings are good. Intake plenum gaskets were oversized mr gasket variety and also cut to fit. TV cable is adjusted as well.

I'm guessing I've just hit a wall where tuning will really wake the car up. It's a very reliable combo, and I've put thousands of miles on it over the last few years taking some long trips down south and up north. Just need to dial it in to get the most out of it. Thanks

big hammer

If you aren't running a wide band AF gauge, you literally have no clue if it's too rich or too lean. Either will kill your power.

A good wide band and adjustable fuel pressure regulator could be your best friend right now to get your WOT AFR around 12.5

TTOP350

iTrader: (8)

Was this a 350 car to begin with??
Is the correct 350 knock sensor in it? (I don't run them in my cars)
Have the correct 350 ESC module ??
350 Chip as a starting point?

norcalz28

iTrader: (13)

I have an AFPR and air fuel readings on the dyno were floating around 12.0 at WOT. For tuning purposes sure, I could invest in a wideband o2 sensor. I was looking for input from similar combos to see if I am where I should be or what with the mods that have been made, as a baseline. The consensus seems to be that the tune needs to be adjusted. So that's where I'll start.

Yes it was a 350 car and yes the knock sensor is the same as is the esc

big hammer

I like having a wide band in mine. Little more accurate than a tail pipe sniffer and it takes the guess work out of it.

12.0 is on the rich side but not worth 50 hp.

Orr89RocZ

iTrader: (20)

Yeah theres some hp there but not sure its gonna add up to where i think that combo should be.

I would check for false knock and see if its pulling all the timing out on the run. My 305 car does this

Copperhead

My 383 6-spd is making around 300 rwhp, my engineer buddy says his desktop dyno suggests advancing the cam (XFI280) will give another 50hp. Haven't tried it yet though . . . just a thought. Drives really well as it is, 370 rwtq, but he doesn't feel the TPI or the tune are the restriction.

TTOP350

iTrader: (8)

Good. Base timing is at what?
Fill with 91-93 octane, fuel psi at 50ish, base timing at 10-12degs and unhook the knock sensor. I have had nothing but problems w them.

Then retest.

norcalz28

iTrader: (13)

Base timing is at 6'btdc now. I have played with advancing it some but I lacked the data logging equipment to see what difference that made, besides seat of the pants. I have 91 octane in her now, and the current tune has knock disabled. FP is set at 45-46psi with vacuum disconnected. I have had it set to 50psi before but did not feel that it was beneficial, ran real rich.

Definitely suspect the false knock to be an issue. These pistons are pretty noisy, and I understand it was a major concern for a lot of people early on which led to the redesign. The noise doesn't bother so much as the sensor thinking it's knock. But as I mentioned, this tune has knock sensor disabled.

Will

yaj15

iTrader: (3)

Have you contacted TPIS or Lingenfelter to see if they can come up with a tune?

norcalz28

iTrader: (13)

Haven't tried contacting them directly. I doubt LPE does much if any tpi stuff anymore, but I might see if I can get a hold of someone at TPIS. I think at this point the timing being pulled out at WOT is the most likely culprit. That would explain why I get out of the hole well, but just fall off down the track. Dyno chart also looks like an etch-a-sketch under WOT which is kind of suspect. Anyway, thanks fellas. I'll work on getting some data logs captured and see whats going on.

Will

RyanJB

If it has the knock sensor disabled I don't see why it would be pulling timing at WOT. It pulls timing based on knock counts and if the knock sensor is disabled it can't make any changed as far as I know

norcalz28

iTrader: (13)

I have two memcals and one has a base tune with knock disabled, the factory tune retains normal operation. Car actually runs nearly a second faster with the factory tune installed. So something is definitely off with the new one, at WOT anyway. It behaves well under normal accel and off idle.

RyanJB

Who made your new one?

norcalz28

iTrader: (13)

Scott Hansen

Steve Mack

iTrader: (5)

Go with the EZ EFI set up from Comp Cams.It's self learning and has a life time warranty.

norcalz28

iTrader: (13)

I'm trying to get the most out of this combo. That being said, I've barely scratched the surface. I need to stay emissions compliant as well.

Will

Street Lethal

iTrader: (16)

Will, you are exactly where you should be in terms of horsepower. Never look at the parts installed when determining the if's and why's in terms of how much power you should be making in comparison with another, but always look at your fueling. You are running 24# injectors, and assuming an 80% Duty Cycle, those injectors are good for 320-FWHP, and around 260-RWHP, which is where you essentially are. If you max the injectors and/or bump up the fuel pressure you may see a tad more, but not much. It's only a 268 cam...

norcalz28

iTrader: (13)

That's a real bummer to hear. I know the cam is on the smaller side, but I was expecting to be able to get this combo to the 300rwhp mark, albeit with extensive tuning. Maybe still achievable, but thank you for your input.

Street Lethal

iTrader: (16)

Will, there are two key things here that you would need to know ahead of time to achieve that 300-RWHP number with what you already have. One; where your injector Duty Cycle was during that dyno, and two; where your RPM peaked. If the injectors were going static (100% plus duty cycle), or if RPM was limited and not maximized and essentially being held back, then that means you are leaving a lot of horsepower on the table because you are either running out of fuel, or your timing is not where it should be. Increasing fuel pressure from 43.5 to 55 with 24# injectors will make them flow as if they were 27# injectors, which are in fact good for 300-RWHP, but you won't do that unless you know for sure your current tune's fueling is in fact going static. Double check your spark advance as some tuners will make it a little too conservative on purpose, and fix as needed. Then, check to see if the injectors are going static. If they are, then you need more fuel, then you can increase fuel pressure, tune the VE again, and do another dyno session...

Orr89RocZ

iTrader: (20)

I disagree!!!

This combo was never tuned!! Factory chip runs faster than his custom one
It will make more power when tuned

And 24lb will do 340-350 whp.

norcalz28

iTrader: (13)

That's great info guys. I'm sticking with the combo for the foreseeable future (baby on the way) I plan to do some tweaking this summer and see what I can accomplish. I will post changes as they occur. Again, thanks for all your input.

Will

Street Lethal

iTrader: (16)

The math does not lie. Assuming 415-FWHP to essentially cover 350-RWHP through drivetrain loss, 415-FWHP (or 350-RWHP) would need 32# injectors at an 80% Duty Cycle, and/or 26# injectors at a 100% Duty Cycle with 43.5 fuel pressure. One can disagree with this all they want but that is the math. If the engine is not calling for more fuel than it will not make 350-RWHP with 24, 34, 44 or 54# injectors, as it is what it is, that is its' air flow...

However, if then engine is calling for more fuel by way of a bad tune though, then the only way to satisfy that fuel requirement of 350-RWHP as opposed to his 250-RWHP with these very 24# injectors would be by running them at 100% Duty Cycle while upping fuel pressure at least 12 points higher making them flow closer to 27# injectors, in turn providing adequate fueling for 415-FWHP, or your 350-RWHP. I am not interested in this person did this and that person did that, I only care about the math used to calculate, and his math in terms of calculated horsepower with his injector size is spot on; 250-RWHP with 24# injectors at 80% DC, or 315-FWHP...

Will, spark advance can be looked at as your torque control. If by chance your timing in your tune is very conservative, then your torque will be down, in turn bringing down horsepower because horsepower is calculated torque. Correct the spark advance if this is the case, and power will go up...

Orr89RocZ

iTrader: (20)

I'll wait for you to explain bsfc values...

Regardless, duty cycle this /that and 24lb has nothing to do with why this motor isnt making power

TTOP350

iTrader: (8)

This^^^^^^^^^^^ I think 350 may be a bit optimistic buuuut it could do it.

norcalz28

iTrader: (13)

Ya, I have illusions about making unrealistic power. But the heads, cam, and hogged out tpi along with all the other things I have done should get me close to 300rwhp, which is where I want to be.

VincentZ28

iTrader: (2)

I know what you mean. I put together a TPI Vortec set up with a ZZ9 cam and it only made 290whp@4500 and 366wtq@4000. The manifold was opened up some and the 062 heads were ported too. The Edelbrock runners are hogged out. Using 27# injectors. All this through 700r4 Trans with 3.23 gears. Kevin91z did the tune. Gonna put a Super Ram on it to see what the difference will be.

Orr89RocZ

iTrader: (20)

I'm not saying this combo will do 350whp. Maybe with a single plane but 260 or whatever is way low. Full bolt on l98 does 250-260whp

Stock maf tunes will just about run most combos. They may start and drive seemly ok enough. But wot can be a different story

Case in point: my 383 hsr. Stock chip with very basic minor changes for injector size and idle rpm desired, drove and started really well. It needed idle work to be smoother and more stable but it worked.

However even with 40% added to pe enrichment, it was still 16-17 afr at wot! amazing it even ran.

Another combo, hsr 360 with afr 190's and 280xfi cam. Stock arap bin with again minor changes for idle speed and injector size, ran well at part throttle and idle. This time however it was pig rich at wot! 10:1 afr. I took out 15-20% in some areas and some timing tweaks, we got the car running from mid 8's at 82 mph to high 7's at 86-87 mph in 1/8 mile. Thats a huge change.

Get a wideband or scanner to read narrow band voltage and see what its doing. Should be closer to 290-300 whp imo

TTOP350

iTrader: (8)

My stock 89 350 chip is running a 400 stroker w a fairly good size solid roller, afr 245s and mini ram. 20-22 mpg too.
Yes, it needs tuned badly

norcalz28

iTrader: (13)

I agree with your assessment Orr, I think the place it is most lacking is WOT. I'll get some data logged and see what I can do to get a little more out of it with just adjustments, then I can start in on tweaking the tune

Will

MrWillys

If the op will datalog the car then I can help. Without data you're just guessing. 30% of logs I get they are pulling one or more codes. My favorite is can you program out my mass air flow sensor?

1MeanZ

iTrader: (9)

On the whole, I agree with much of what has been said here. I've tuned a couple cars built very similar to Norcal's, in fact one of my cars has a very similar engine to his.

I am skeptical of your ported stock base, and curious what headers you are running.

Without a wideband O2 sensor, you're completely lost. I like to use the Innovate MTX-L, I permanently install them in the car. The controller has a WB output for the gage and a NB output for the ECM, which I utilize. I completely get rid of the factory O2 sensor. (I do still have the factory plug on the car, and I keep a spare stock O2 with me that would plug right back into the car)

Hit up www.moates.net and get this. http://www.moates.net/apu1-autoprom-....html?cPath=64

Then the first thing I'd do is put the stock chip back in it and start from there. I DO NOT EVER disable the knock sensor unless I know for a fact I've got false knock. Also contrary to what some might say on here, I'd keep the WOT fuel in the low 12s to protect your converter, just my $.02

Steve Mack

iTrader: (5)

A stock ported manifold if done right can move more air than most people think it can.

1MeanZ

iTrader: (9)

I'm well aware of that, but over the internet I can't tell how well it's been ported, and he didnt post flow numbers. Were the port roofs raised? Was material welded in around the injector bungs? Even ported TPI isn't the best breathing setup so HP numbers are going to be pretty low. But I'll call to attention Vincent's torque numbers listed above. He's making roughly 450ftlbs at the flywheel out of a 350. Thats astounding and I'm sure it's a fun car to drive.

no new tires

Whys that?

1MeanZ

iTrader: (9)

Keeps exhaust temps down to help protect the converter from overheating during extended WOT pulls.

no new tires

How did you figure that?

Dyno Don

iTrader: (7)

I was running the dyno, I didn't see 450 tq from a 350.
My 355 makes 430 tq to the wheels.

1MeanZ

iTrader: (9)

It's common knowledge, or at least I thought it was.

1MeanZ

iTrader: (9)

Don, I said 450tq at the FLYWHEEL. Check my post again....

Dyno Don

iTrader: (7)

Yeah...I guess 366 would be close to 450 at the flywheel