hey guys! i'm building a 383 for my '92 and i'm getting Lloyd Eliott LE1 heads and cam. I was wondering what size fuel injectors i should use. thanks!!!

 

Depending on how much horspower you are planning on making....

You would probably be in the neighborhood of 30 pounders...

Mo

 

A lot of SUPER running 383s, 396s, 406s and 434s running 24# injectors.

These cars are all sub 11s and 10s cars. No need for more.

Bigger is not always better when dealing with cars. Almost always you want a good balanced combination. Overkill in areas, leads to less efficiency. Less efficiency leads to less performance.

A motor is simply an air pump. The amount of fuel a motor needs is based on HOW MUCH AIR IT CAN MOVE. If a 434 CI motor running 10.2 with the best 23* heads and intake on the market today can run for YEARS on 24# injectors, there is no reason that a 383 can't.

 

At least a 30.

Loyd reccomends at least a 30 w/ LE1 on a 350 car.
http://www.eportworks.com/LT1LE1.htm

 

Talk to whomever you get to do the tuning. Let them decide.

 

basic rule is horsepower PER CYLINDER divided by 2.04 = injector lb/hr for recommended 80% duty cycle...then its up to the ecm program (tuner) to make things happen at the right time

if you have a 572 bb that you only want to rev to 4000 rpm and make 250 hp---250/8 = 31.25...31.25/2.04 = 15.32 lb/hr, so a 16 lb injector would be plenty.
if you have a 305 sbc that you somehow will get 3000 hp from---3000/8 = 375...375/2.04 = 183.82 lb/hr, all yuo need is to find an injector that big (somebody probably has em somewhere) and pump to match,etc.

 

With all due respect, the 383-434s I have mentioned above are ALL making way more HP than this "loyde whoever" and that is without the ** by the HP claims.

Again fuel is the easy part of the motor makeup. Getting the most air you can efficiently pump through the motor is the hard part. CI is merely the air potential displacement of a cycle of the motor.

Some say to go with what the tuner says, some say to go with joe blow, the smart thing to do is go with what WORKS.

Lots of good running cars use 24# injectors. Here is a 420ci motor that is still a little fat with fuel on 30# injectors that could be running 24# that runs 9.7s



Lots of others also seen here run 24# injectors.

http://www.azzatochips.com/AzzatoChips/Testimonials.htm

Go with what works in similiar combos. There is no better or safer way.

 

I think the issue we always seem to encounter is that BOTH larger and smaller injector sizes (to a reasonable degree, depending on the engine combination) have been proven to work. In the end, the tune winds up being the determining factor.

As vader86 said - let your tuner decide.

 

Jesse,

Your arrogance never ceases to amaze me. "Loyde whoever" happens to be Lloyd Elliot, one of the best LT1 head porters out there. His heads happens to be on some of the fastest z28's in the country.

OK, maybe some of his customers do not have cars as fast as your "creation" but he has created many combos that, as you say, "WORK".

If you cars are sooooo great, why do you not have as loyal of a following as Lloyd?

Before you go insulting someone's name, why don't you do a little research and see what this "Lloyde whoever" is all about.

 

Who knows how high the fuel pressure is, that they are running these #24 injectors with. Furthermore, how high is the duty cycle, surely not 80% but rather 100%???

 

I'd think some SVO 30#. Good choice w/ LE also.

 

Think what you may about my comments, but this lloyde I had never heard of in my many years of being here. Perhaps its because he deals with LT stuff, and for the record I did click on the site and his testimonials etc said "soon to come". That is as far I went.

Besides, since when did someone porting a head, make them an authority on injectors?

Again fellas I was just trying to point out to the guy asking the question that there are MANY good combinations here on the forum that outperform 95% of the cars here with 24# injectors.

As always some of you do not like what I say because it is based on REAL world results, but that is what most people care to see - not because someone else, whoever it is says something should work.

I believe in the old addage: Don't tell me about it, show me.

Which is what I do in my advice. If you don't like it, don't read it. And don't come here looking for fights with me about stupid crap like this.

And do you honestly think that we would be putting together the setups we have, travel hours to the track weekend after weekend trying to better our setups, and leave the EASIEST thing to get (fuel) out of the equation.

Common fellas, you don't have to like what we say or what we do - but give us more credit than that.

Its all good though, differences of opinion on things are what make us all think and stay sharp - and your "proof" we are doing something wrong in our setups is always welcome. Never turned down the offer to make more power

Have a good weekend guys, and hope the original poster can see the light of reason.

 

I think Elliot is probally one of the top 3 in head porting right now. Hes been around for at least 4 years that I've known. Hes extremely popular and has done some fantastic work. His packages are some of the first I remeber seeing that would do over 400rwhp on a stock LT1 shortblock.

Real straight shooter also.

 

I run a Lloyd Elliot setup but won't bring that into the fray.

I would bet that an LE1 combo would do wonderfully on some LT4 (28# @43psi) injectors.
If you could get some then it would mean less ECM/PCM adjustments. It would probably be just "plug 'n play". The LE1 will only need minor fuel/spark tuning in the 5000rpm+ range compared to the stock program. The stock program is pretty darn good (at least in '96).

My LE2 combo (on a 350) and 37# Racetronix injectors needed major PCM adjustments. I'm still fine tuning.

 

I’m going to jump in here with some objective data for a change.

First…..Who in the hell do you think you are to insult people just because you haven’t heard of them. The world must spin around you.

Second….yes you can run a smaller injector but at what fuel pressure?? You supplied no factual data at all.

Third….using a fuel pressure of 43 psi Haltech used one of my former cars as a mule to develop an engine managements system. Using OJECTIVE IMPERICAL (not trash talk) they found in a 350ci motor using 24lb injectors with ported heads and 306 cam making 395 rwhp….. the injectors went static @ 6000 rpm. Based upon that data in a six speed car, I say when you approach the 400 rwhp it’s time to start data logging comparing the data with a wideband 02 sensor.

If you’re a hardcore hot rodder and don’t believe in dyno’s (like some fools on this list) then you read the plugs.

Fourth…… in a car 12.5 to 1, 398 ci motor making 465 rwhp again using 43 psi the car went lean on the dyno around 6500 rpm with the fuel table maxed out. Replacing the 30 lb injectors with 42 lb injectors solved the lean problem but did not make any more hp.

Based upon that data is a six speed car using 30 lb injectors and making in the 450 rwhp range, it’s time to start thinking about larger injectors.

How about a little less trash talk and a little more objective information to back up the trash talk??

 

D48m,

Look, there was no insult on anyone name....the name posted I was not familiar with and when I went to the site it did not have anything there in the way of showing me that this guys recommondation was valid or not. As stated the testimonials and the everything else for that matter was under construction. IF the guy does good work - great but that doesn't convince me that anyone needs bigger injectors.

The comment I made was you don't need to look any further than the forum here and the good MANY cars here in the CI range that the original poster had asked about.

There are MANY very GOOD examples of very LARGE CI motors running in some of the more CREDIBLE forum members like:

RALPH (406)
COrkvette (434)
Beachbum (383)
85vette (383)
corvette0096 (383)
My 406 (406)
and I am sure there are others that ALL run 24# injectors with a GREAT DEAL OF SUCCESS.

ALL these cars above are making great power, and running 11.5 and less down to 10.2sec ETs. That alone sets the record for what is TRUELY needed to make good EFFICIENT power.

Now if you want to argue something which I could care less to do - explain to us how all these cars are cranking out this much power and weekend after weekend if they do not have enough fuel?

As I said all these above guys drop tons of $$ on performance for their cars, do you honestly think any of them would skimp on a lousy set of injectors that cost 300 dollars if they thought there was a need for them?

And not to mention the good majority of the cars above have TONS invested in intake and head setups and solid roller cams MUCH MUCH larger than the setup in question will have.

If you want to see A/F do some searching it has all been posted before. My DFI WB data is posted all over the sight if you care to look. As is corvette0096 dyno readouts with A/F data showing perfect fuel ratios all through the entire RPM range.

A motors efficiency is what dictates the power it will make and the amount of injector required(BSFC). If you have a 383 that is sucking the injectors dry, then you should NOT be looking for a bigger injector - you sould be looking to see what is causing the inefficiency. Just because you can drownd a motor with fuel doesn't mean it will make power.

Your own statement here is a PERFECT example of what I just explained above:

"Fourth…… in a car 12.5 to 1, 398 ci motor making 465 rwhp again using 43 psi the car went lean on the dyno around 6500 rpm with the fuel table maxed out. Replacing the 30 lb injectors with 42 lb injectors solved the lean problem but did not make any more hp."

Now we have 434 CI motors making over 600hp with 24# injectors and running the same ones for coming up on 5 seasons in Corkys car. His car sees at least 6 passes on average a weekend and LOTS of street miles. I would love to know how he does it with 1/2 the injector your SAYING won't work.

Corky and I went down this same exact path with the guys that swore up and down that we could not run 10s with stock MAF on our cars. It went on for months about them claiming foul play just as you allude to here. That is until a few of them showed up at some of the tracks we go to and inspected the cars. We openly welcomed the suprise visit/inspection - and then happily showed them on the strip what they could do, which at the time was .3sec quicker than thier EXACT same setups with speed density. At the end of the year and now we have extended the gap in our setups to over 1 FULL SECOND quicker. Because we continue to recognize the areas of potential power, and these guys continue to play with things like bigger injectors thinking their motors will majically make 100hp more with doubling the injector size.

As with them, I welcome you or anyone else that would like to see the cars run with EXACTLY what I say above. Its not voodo majic we are pulling. Its what I always say it is:

Well balanced components that compliment one another from air filter to exhaust tip.

Have a good weekend

 

hey guys! thanks for all of the input! i really didn't mean to start anything though. i have another question now. it may be put up in a new thread also. i've been doing a lot of research on the forum and off. i need a new tranny for this build becust the stock one won't cut it. i have a 700r4 with a littl over 160,000 miles on it. i saw the Raptor Transmissions from www.transmissioncenter.net, i was also told about www.pro-built.net and www.rosslertrans.com (i think that's it) by ski_dwn_it. my biggest thing is cost. I only have like $1500 - $2000 to spend on the trans. i can't see that the 383 that i'm building is going to make more than 450hp. if it does, then i'll be stupidly impressed! that being said, which 700 would anyone recommend in my price range (including the torque converter) to mount behind the engine? thanks again!!!

 

Nothing should have gotten "started" in the above thread, so you have absolutely NOTHING to appologize for.

Trannies are another thing I see alot of people getting burned on. You do not want to skimp on the trans. Its not fun to replace and costs you a ton to do it, both in time and shipping etc.

Pro-built.net has probably one of the best reputations I have ever seen for 700r4 trannies around. I ran one for ~2 years and never had a single ounce of problems. It saw many runs and worked flawlessly.

Rosslertrans.com is another that is above and beyond in the reputation department. Nearly every super stock car you see has a rossler trans sticker on the side, and the guy that owns the place is an avid racer. Most places you call and tell them that you will be racing, tell you then there is no warranty. Carl will tell you that is what its built for, do what you like with it - you won't hurt it.

Both places are very good places to deal with and you have no worries you will get exactly what you want - A GOOD, DEPENDABLE transmission.

85vet just ordered and got a rossler 700r4 after going through several last season from another vendor. He would have perhaps current costing for you. I will ask him if I talk to him and forward you the information.

 

hey ski! thanks for the info! that's something that i definitely agree with you about. i'd rather not have to replace the trans EVER after it goes in. if the cost is on the topside of my budget, then whatever. i'll do it right the first time. if you talk to 85vet soon, it would be greatly appreciated. thanks everyone!!!

 

Farscape, for injector sizing, I would use whatever your tuner recommends.

On injector sizing I would like to point out 3 examples from the pros on this matter.
1. GM built the 92 with 23.8lb injectors rated at 43lbs. When they built the LT4 they used a 28lb injector rated at 43lbs. Obviously they seen a need for a bigger injector for the additional power output of the LT4
2. Holley offers the stealth ram mpfi systems for small block chevys. The kit is rated with 24lb injectors to work with 300-385hp. The 30lb kit is rated for 385-480 hp. and Ill bet that these are flywheel hp and not rear wheel hp nos.
3. My car has the mods shown in my signature. As you can see it is less agressive then yours will be. It has been mailorder tuned and dyno tuned by Alvin at www.pcmforless.com I am still running the stock injectors but Alvin has them at max. duty and we are still going a little lean on top end. Alvin suggested I go with 30lbs but I have not had the time to do it yet. Also I am considering other mods to the car at this time.

One other point I want to make is I do believe that whatever injectors you use will require a retune of your car. The reason being is the speed density is a lot less tolarent of changes then the maf systems are.
When I first did the work to my car I had a so called tuner do a custom chip and he did little or no mods to the fuel tables, spark tables, etc. As a result it ran very rich at idle and part throttle. After 3 attempts at reprogramming he kept telling me the problem was my car. IMO he just did not understand or know how to programm a speed density car.
At any rate I got a mail order tune from Alvin and the car ran great. Idles smooth etc. Then about 1 month latter I went to a shop where he was dyno tuning and he fine tuned it a little but only got 6 more hp out of it. Thats how close his mail order tune was.
As far as what transmission you use I dont have a lot of info to offer on that. I currenty have a transmission rebuilt by a friend. He put kelvar bands, and red alto clutch packs in it. Also he used a superior shift kit. For some reason he didnt want to use a transgo. But I believe a lot of that just comes from personal perference. Also I am running a yank converter 3000 stall.
The one thing that has not been mentioned here is with the power you are running you will probably need to upgrade to a dana 44 if you are still running the 36. The 36 is a weak link when you start making alot of power.
Good luck with your motor and let us know how it turns out.