Made it to the track tonight. KCIR, MO. Temperature was about 85*, the high was a muggy 96*!!! Anyways, on to the runs. These were my two best:

60'.......2.370
330......6.000
1/8.......did't read for some reason
mph.....same as above
1000'...11.569
1/4......13.734
mph.....104.26


60'.......2.463
330......6.213
1/8.......9.216
mph.....82.49
1000'...11.791
1/4......13.954
mph.....104.45

I had a .506 and .524 reaction time on a couple of other runs!!!
I still have some major traction problems, I'm hoping some LCAs and relocation brakets help. I was also running pretty hot as well, around 200*. In trying to cool the engine, I left the fan on and my weak a$$ battery died, so I didn't get to make anymore timing changes or runs, but I think I could have broke 105mph with a little more fine tuning and a cooler engine. My throttle cable broke yesterday as well, so I had to jimmy rig it until the new one comes in, and I don't think I was actually able to go WOT.
I'm pretty confident I'll be able to break 106mph after a new chip and cooler weather. Hopefully, I can get those darn 60' times down as well and break into the 12s. Not t0o bad for a 2bbl TBI if you ask me. It's fun whooping up on those little Cobras too!!

 

Very nice times. Get those 60's down and you should see low 13's.

 

Your 60's look like mine. Although I wish my traps looked like yours Nice job man!

 

Is this an everyday driver car too?? What kinda gas mileage do you get with it? I was thinking of going with the 383 TBI also but with the lack of funds, I may just switch to a 350 TBI.

 

Thank you guys. Hopefully I'll have some new suspension next time I make it to the track. My goal for this season is to break the 12's and get a trap around 106mph or better. Then next year it will be time for a different injection set-up.
It's kinda an everyday driver, though I usually drive my beater truck to work, and try not to drive the 'maro everywhere. She is definetely streetable though. Best milage to date is 26mpg highway, average being 24-25mpg highway. Fuel injection + T-56 makes for nice milage for sure.....well that is except for city driving.... gas milage is usually around 13mpg in town, but I tink a lot of that has to do with a heavy foot.

 

Whats your launch RPM's and how hard do you dump the clutch?

 

Normally, I launch between 2,000-2,500 rpm. It was a little tricky this last time at the track though, because of the way I had to rig my throttle cable after it snapped. A couple of runs I actually bogged down. But my new cable is in and good to go. Now to invest in some copper header gaskets, since I blew another one on my first run!!!

 

Man suspension stuff is so worth it. I finally got around to putting all my stuff on and holy ****, its a new car. I cant get the ****ty Kumhos to break loose for the life of them.

 

Seems to me, a street engine shouldn't need copper gaskets. Maybe there is an issue with the finish/straightness of the block or head decks. Could be detonation... I'd tend to think the problem isn't the gasket itself.

 

Oh yea, Edelbrock makes a real nice Vortec adj. throttle bracket. You have to fab a housing up for the curise bracket but the throttle and tv work great.

 

Well, I think the problem with the gasket are that the bolts always back out. I retorque them regularily, but apparently that is not enough. And i'm not sure if the headers are 100% flat anymore. Anyways, I think $40 on copper gaskets is much more cost efficient than purchasing brand new headers, especial when as broke as I am.

 

argh

I misread what you wrote. Somehow I had it in my head that your HEAD gaskets were failing, not HEADER.

 

hey r90camaros what kind of induction sys do u have, where did u get it from. lil more specs, i would like a combo like yours in my monte.

THANKS

Albert

 

I'm using the Holley 670 w/ 85pph injectors. The ecm is the stock 8746. The intake is pro topline's version of the edelbrock performer. I'm using a 1/2" adapter with a 3/8" gasket underneath it. I also polished the TBI bores and smoothed out the openings, as well as sanded down the rough castings on the injector pod in homes of more air flow. I'm also using an injector pod spacer as well. I bought the holley unit for $300 from Auto Zone. The injectors cost me around $160 I believe.

 

IMO not a good MPH for that combo. Go carb, and see better times, bottom line. MPG might go down but IMO thats better then the MPH going low. Besides my 355 carb gets better mileage then my LO3 did anyday

 

Dude, you already stated that in another post yesterday. 25-26mpg is not bad, especially considering I run rich at cruising speeds right now because I need the extra fuel pressure for WOT. Not to mention that she's probably at about 350hp right now and capable of over 400hp once I get the 2bbl tbi replaced.
And no, I am not going to carb. That would be stupid. I will eventually go with a 4bbl TBI so I get the airflow my engine needs, while keeping the same gas milage and reliability. I do need my car to start in the winter.

 

What fuel pressure are you running and how much eprom tuning? Have a bin file I can comment on?

 

sigh .... why is it every time someone asks how to make their tbi faster/more effiecient, someone always comes out and says "get a carb" or "tbi sucks"?

don't they have a "get a carb, tbi sucks" board on here?

 

Currently i'm running 22.5psi. Unfortuantly, any more fp and the spring bottoms out not to unlike yours was doing. Unfortuantly, I have only had one chip burned since the fuel pump was installed, but it is off primarily because my knock sensor is going haywire and was on the winaldl data i sent brian, so he really didn't have that much to work with. Haven't figured out why, my guess would be either the sensor was over torqued or my open exhaust is causing false knock. A dumby knock sensor is the temporary answer and what I have been using. BLMs are currently range from 118 to 122 when cruising. One day I hope to get into prom burning, but the commander 950 seems sooo tempting as well.

I hear ya about the carb thing. A guy I know was talking trash about my n/a tbi and how his carbed 350 z28 was going to eat me alive with his 125 shot. He only got me by .5sec and 2mph in the quarter and he sprayed from the 60' mark. Give me a 125 shot
Granted he only has a 3 speed, but he only gets 10mpg on the highway. But hey, brody knows all, tbi sucks and carb rules!!!lol

 

They should.....

 

 

At least my carb idles good. My TBI would just die for no reason. Generally ran like a model T. I replaced everything on my TBI and it didnt help anything. Switch to carb and Ive been happy since.

 

The way I see it, going to and sticking with a carb is for the people who are too stubborn and unwilling to learn. No if, ands, or buts. A carb may be the simple answer which is fine if you are a simple person. But if you are willing to learn, and want maximum performance throughout the entire spectrum, fuel injection is the way to go. It's proven, and doesn't take rocket science to figure out.

There really shouldn't be a "get carb, tbi sucks" board. It should be the other way around. If as much time and effort was spent on tbi tuning as there has been on carbs over the years, then tbi would by far pass anything a carb had to offer. But unfortuantly, too many people want the easy quick results, instead of a more time consuming process even though it would lead to better results. But it is their loss. Thankfully, more people are working with tbi as a performance injection, and making giant leaps with strong numbers, and in my opinion, are starting to make the people that have switched over to carb feel insecure about their choice.

Oh, and I promise, my tbi runs nothing like the Model T (which ironically was obviously carburated

)

 

WOW, I couldn't have said it better myself.

 

I don't feel that TBI has the flow potential of carbs. Fuel injection however is much better I give you that. MPFI is what I want. Not TBI. The two barrel TBI is choking that 383.

Most people are always looking for fast results? Some of us don't want to take the time or spend the money to get prom burning equipment, scanners, ect. I don't think a 670cfm TBI would be enough for your motor? If you wanna spend the money and take the time to tune that TBI to your motor thats fine. Ill get my vacuum gauge and spend the next 10 minutes tuning my carb...total cost of tuning equipment...15$ for a vacuum gauge.

But if you wanna stay TBI thats fine. I at one point thought I wanted TBI...I went carb and haven't looked back since.

 

Sure it does. That is why there are 900cfm tbi's. Anymore than that the car probably wouldn't be streetable. Theoretically, you could use a dual 4bbl intake with two 900cfm tbis for 1800cfm though. You're right, but unfortuantly all after market mpfi systems are too expensive for me, including all the aftermarket parts needed to make tpi flow. TBI is the perfect middle ground for those who are budget minded. Perhaps oneday, I will have a stealth ram or something of the sort, but for the time being, tbi is working out great for me. I have said that many a time. I just hope to settle all the debates as far as how much power the 2bbl tbi can really support. Next year a 4bbl tbi is going on there.
My first custom chip cost me $30, and $10 for any mods/chip changes after that. Winaldl is free, and it only takes 15 minutes to data log. Changing the chip takes 2 minutes. The longest it has taken a new chip to arrive from tbichips.com was 5 days. I will more than make up for the cost difference in gas as well.
That's because all of the tail lights are now in front of you.

 

All right everybody. The reason for this post was not for a carb-tbi debate. It is for those who plan on using tbi, and the numbers achievable out of it. If you are for carb, then fine, but go post in the carb board instead of wasting our time over here. It is unfortunate where this post has gone, but oh well. I hope to have new and improved times and traps for all you tbi'ers soon though.

 

How you figure? The car is much faster now...

 

EXACTLY

this is the tbi board

it's for people who want to get more out of their tbi.

people who want to switch to carbs can go to the carb board.

i don't think there's anyone on here who wouldn't agree that a carb is easier to tune and flows more air than a tbi.

the point is, tbi is what we have. i have a yearly emissions test to pass and am not interested in having to swap back to tbi every year. my only option is to remain emissions legal. that means tbi or (gasp!) tpi.

i'm going to get as much out of my tbi as i can before i give up and go to tpi. period.

if the people who've switched to carb are so happy about it, then go to the carb board and crow to your heart's delight, but don't sit here and snipe every post from some poor schlub trying to make what he has a little faster.

just my opinion.

 

Let me save you some time and money. I've already tried it. You can't get enough fuel in the engine w/the injecters that are available (not big enough to support 400hp) the only 4 inj. TB you can get is the Holley and it stinks.
So I gave in and got the MPFI system.
Just trying to give you some insite here.
Don>>>

 

Why do you say the injectors aren't big enough? I'm currently running two 85pph injectors and have plenty of fuel, just not enough air flow. The holley 900cfm TBI comes equipped with 4 85pph injectors which is supposed to be good to for 500hp. I'm guessing I'm currently around 350hp or so with just the two. I'm not banging, just curious as to how you came to your conclusion.
I have looked into mpfi systems as well, but unfortuantly the vortec heads limit my possibilities, as do most of the prices. Perhaps one day....

 

I had a 454 TB 95# inj. and they were maxed out on the chassis dyno w/383 @5000rpm's and showing 15-1 afr w/WB02.
The combo was w/ZZ4 cam, ported Sportsman II heads, 1 3/4" headers and 3" cat back ex.

 

What kind of fuel pressure where you running?

 

!5#

 

If you were only running 15lbs of fuel pressure through those injectors that would be why it was maxing out. People on here with fairly built 350's like JPrevost with the 350 HO is running 28psi IIRC. You had a 383, I'm sure you needed more fuel pressure.

 

The problem is, they are TBI injectors designed to run at 15#psi.
Jacking the pressure to combat a wrong situation doesn't seem like the right thing to do for me. I don't remember the formula right now but IIRC it would take something like 105#phr injectors to produce 400 HP @5000 rpm's, so that is why you need 4 85#phr inj. in the Holley unit.

 

The GM (Rochester or Delphi) injectors will easily go over 30 psi. IIRC, they have been tested up to 60 or 70 psi before they start locking up.

I ran 350 injectors (org/blk's) at 30 psi for a couple of years. I also run BBC (drkred/drkblu) injectors and run these at 16 psi.

Keeping the RPM down also allows more time for the injectors to flow fuel.

This whole TBI vs carb debate is BS. If GM had produced 4bbl TBI's like they did quadrajets it wouldn't even be mentioned (but then again many folks hate quadrajets too. . . .).

RBob.

edit: four 85#/hr injectors are good for 578 HP at 85% DC and .5 BSFC.

 

And r90camarors, nice times, good job. With a little more traction (as you mentioned), a tad of tuning and I'll bet you will be in the 12's.

RBob.

 

I'm looking into building a 383 for my TA, and I've always wondered if TBI could support a healthy 383. So I will be following in your footsteps, probably. Keep us posted on the progress.

 

I challenge any mail order or on the shelf tbi (even using winaldl) to outperform on my car. I'll also challenge anybody that has a 550cfm 4 barrel carb or 670cfm 2 barrel carb to bolt it onto my car and drive the car faster my current setup.
Dude, that 383 is beyond winaldl tuning. You need to DIY or waste your money and time. 5 days shipping is a lot for me, in 5 days I could make enough money to pay for the tuning tools avail to the public and get your groove on. My car runs on 87 octane all the time now and for that reason alone I wouldn't trust somebody touching the tuning unless it was Bob. People have their abilities, mine is patience, hence TBI. Hopefully with the release of the promulator there will be no need for a burner! Just plug in and update your configuration, what a dream come true. Even with flash proms it's a mess programming away from home. Having extra power supply, wires, a couple flash proms, lots of software.....
Seriously, get into burning your own eproms ASAP and even though it is semi expensive the rewards are worth it. Just look at my gas milage and soon my new times. I'm not doing any rocket science here, just using data.aq and even with winaldl as your only source you can do wonders.
Here is a personal example for you. You say open headers might be causing false knock, so burn an eprom with 10 as the number of knock counts required before timing retard. Then even with winaldl you'll be able to pinpoint your problem.
Oh, and the 4 barrel tbi is going to eat carb guys up from the track to the street, through inspection to sitting in traffic, it's going to be interesting to say the least.
Why I don't like mail order eproms: They killed this board and many cool projects. They stop people from thinking and profit from information that was given to them for free. It's a scam and the only person it hurts is you the buyer.
Even I am reluctant to release information outside of my own personal loop for fear that someone might get hurt by it.
Picture this, guy wants rev limiter and code 43 patch added to his chip so he gets it done by somebody. That somebody can take that persons money and claim that it isn't there fault for any damage it might cause to the motor or the buyer.
BBW, DIY or go carb for the meantime (only applies to somebody with more than just exhaust and intake work).

 

Thank you for the compliments guys.
I hear ya jon. I definetely need to get into prom burning, and burn a chip to perfection. I know it takes numerous chips to get it close to perfect, which is another reason to diy. I guess I have always been worried to do it-which is pretty bad considering I am 3 classes from my cis degree....
I will never knock Brian or tbichips.com, because not only is he extrememly helpful, he offers an inexpensive alternative in a chips that definetely make for a good starting point, and only improve with each change (my situation was lack of time and money because of my little girl). However, jon is right. Burning your own chips not only makes for more timely and exact performance, it makes for more potential tuning tips and tricks.
And ahhhh....the promulator would be very sweet. Is it seriously in developement?

 

edit: four 85#/hr injectors are good for 578 HP at 85% DC and .5 BSFC.
So...does that mean then that 2-85# would be good for 290HP (578/2=289 @ 85% DC?) Then how much would 2 95# @ 28psi
be worth in HP? 350-375 maybe? And how much more fuel can you get thru that small opening by jacking the pressure?
What I am wondering here is are we letting the facts fall by the wayside here in sake of a good arguement?
Don>>>

 

DynoDon,

its a simple math formula, ends up being 318 lbs of fuel from two 95lb injectors at 28 psi (they can be pushed to higher and the same math applies)

which btw is good for 540 hp at an 85% duty cycle.. way more hp than the tbi is capable of supplying effectively airflow wise anyways

 

Wait a minute...if 4 85's are good for 578HP how do you get 540 HP out of 2 95's did I miss something here?

 

yes you did, 95s are rated at 10 psi, you said 95s @28 psi in your question above,
95 lb injectors at 28 psi is like 315 lbs of fuel per pair, i posted a link to the math for that

 

Yes you did. "two 95lb injectors at 28 psi" meaning 95pph rated at X psi then bumping the pressure up to 28. Upping the fuel pressure basically increases the flow rating of the injector-exactly what the fomula says.
Quite a bit actually. You would be surprised.

A couple of other thoughts. 1) Our BFSC isn't .5 or 2) Holley's flow ratings on the delphis are underrated. I say that because if I am running 22.5 psi, I have a flow rating of about 91pph(per formula and based off of the delphi's 21psi rating). At 85% duty cycle that only comes out to 309hp. However, I am confident I am making more power than that, and never have any problems going lean at WOT.
When I ran the 57pph injectors(@21psi) on the 305, I was running around 14psi, which only equates to about 40pph-that of the stock injector, yet it ran very rich.....

 

The GM (Rochester or Delphi) injectors will easily go over 30 psi. IIRC, they have been tested up to 60 or 70 psi before they start locking up. I ran 350 injectors (org/blk's) at 30 psi for a couple of years. I also run BBC (drkred/drkblu) injectors and run these at 16 psi. Keeping the RPM down also allows more time for the injectors to flow fuel. This whole TBI vs carb debate is BS. If GM had produced 4bbl TBI's like they did quadrajets it wouldn't even be mentioned (but then again many folks hate quadrajets too. . . .). edit: four 85#/hr injectors are good for 578 HP at 85% DC and .5 BSFC.

Here we are talking about high pressure or was this low pressure?
Me thinks me is getting what used to be called

 

ok, i'm confused.

here's how holley say you calculate the effect of increased fuel pressure on injector flow rate, uning the example of injectors rated at 24lb/hr @ 43.5 PSI and raising the fuel pressure to 55 PSI:

Rated flow = 24 lb/hrRated fuel pressure = 43.5 PSI

New fuel pressure = 55 PSINew Flow (F2) = (24 lb/hr) x ( 55 PSI) = 26.98 lb/hr....( 43.5 PSI)

Raising the fuel pressure of a 24 lb/hr injector to 55 PSI raises the flow to 27 lb/hr.

when i do the math, i get 30.344 lb/hr, not 26.98

doing it pablo's way, i get the exact same thing.

what gives?

 

You need to state your question better. Everything I posted is true. Even GM runs the TBI injectors/units at pressures of 18 psi & 30 psi. No BS.

(if your question was about the 4 85#'s good for 578 HP, that is at whatever pressure they flow 85 #/hr: 4 * 85 = 340 #hr total, 340 / .5 BSFC = 680 HP at 100% DC, 85% * 680 = 578 HP @ 85% DC).

RBob.

 

Change of flow through an orfice due to change in pressure:

NewFLow = OldFlow * sqrt(NewPress / OldPress)

24 lb * sqrt(55 / 43.5) = 27 lb/hr

RBob.