torqueaddict

I have 3 injectors that are low (9.0,5.2,2.0) so I guess I will be buying a new set.

I have an 89 5.7 with 50k miles, with basically no mods other than a CAI and better coil, and wires and flowmaster catback.

So would better-than-stock injectors help? Also, I accumulate a little coolant and the front driver-side of the block where the intake meets the heads. Would putting a new intake gasket fix that while I have everything apart?

Also, I guess I have the upper plenum off, as well as the runners (and maybe even the lower intake) Any suggestions (under $1000) to get more power - just has to be emissions legal? I think the TPIS system is not emmissions legal.

thanks in advance for any help!!

iroc240_3

Ford/SVO 24# injectors would be a nice upgrade. I beleive your stock injectors are 21 lb.

torqueaddict

I see Accel, Ford, Holly, etc.. injectors that have slightly different dimensions. (as per summitracing.com product details)

Will I have to make any changes to have any of these injectors fit? (do they pop right in?)

Also, I think my injectors are 21 stock. If I go 23 or 24 will I be using an injector too large? (I hear this can cause power loss)

thanks!

torqueaddict

Been doing some searches and heard this is a new upgrade.

see : Bosch Fuel Injectors - Performance Parts - Ford OEM Injector Sets

Any opinions? Better than the Accel set? I was thinking that 24 may be too big (based on other threads) for my stock motor.

ROCITUP

I JUST ADDED LSI FROM 2000 VETTE AND WORK AWSOME. JUST BE PREPARED TO BRING YOUR FUEL PUMP UP TO PAR....MINE TOOK A MAJOR CRAP AFTER THE INSTALL......YOU MUST USE 22 LB INJECTORS OR YOULL REQUIRE REPROGRAMMING.......THAT'S WHAT I WAS TOLD.

torqueaddict

Where did you get the 2000 vette injectors? Just at a dealer?

thanks

ROCITUP

FROM THIS GUY OFF THE BOARDS. ONLY 50 BUCKS , BUT THERES MORE DETAIL TO IT. U CANT USE THE ORIGINAL CLIPS TO LOCK THEM , THEY PRETTY MUCH FLOAT BETWEEN RAIL AND INTAKE. SOME GRIND DOWN THE RAIL BUT THIS CAUSES OTHER PROBLEMS BEING TO CLOSE TO THE RUNNERS. ALSO THE INJECTORS MUST BE ABSOLUTELY IN THE RAIL THEN THE INTAKE IS SECONDARY. ALSO GONNA PROB' NEED AN AFPR AND A STRONG PUMP I HAVE IT SET AT 44-43 LBS.,WITH A NEW 255 LPH WALBRO. AS FAR AS I KNOW YOU CAN GET A GOOD SET FROM E BAY FOR BOUT 60-100 BUCKS. DEALER WILL RIP YOU .MUST BE FROM 2000 LS1 CAUSE THEY HAVE A LOWER PRESSURE RATING.

torqueaddict

Do the 2000 ls1 vette injectors require reprogramming since they're 26 lb fuel injectors? (from what I've read anyway)

I'm looking to keep near stock for now.

thanks in advance...

ROCITUP

NO, NOW IM NOT AN EXPERT BUT I DID LOTS OF RESEARCH....THE 2000 INJECTORS ARE BASED ON A FOUR BAR SYSTEM(DIFF MAP SENSOR) THE TPI IS A WEAKER THREE BAR (LESS) PRESSURE. THE RATING IS ON DIFF LEVELS. SO ON A TPI THEY ARE A 22 LB INJECTOR. THEY WORK FINE ON MY 383. EVERYONE TOLD ME THEYD WORK FINE ON A 350 TPI.... NO PROGRAM REQUIRED. IF SOME ONE HAS A BETTER EXPLAINATION PLEASE SCHOOL ME PROPERLY...............PS SEARCH THE THREADS TO FIND OUT MORE.

QuickStyle

torqueaddict - you would be fine getting 24lb ford svo injectors (stay away from accel injectors) as for your upgrades if you are looking under $1000 go for a better intake,runner,plenum setup. Search the board for the info on alternate intakes. you can find a bigger mouth base intake for under $200 and the runners for around the same price, i personally like as&m or tpis they are the same product with a different name. then there is edelbrock and accel runners also. also try a search on the SuperRam intake, i got mine for $300 (base,runners,plenum) on ebay, i got it so cheap because the guy selling it listed it wrong. those are the only "smog legal" intakes i can think of.

ROCITUP - From my research i have found the same thing, the newer injectors from GM are rated at 4bar(55psi) whiel the ones on our vehicles are rated at 3bar(43.5psi). im not sure exactly what your setup is but it seems to me that you are running a 383TPI with 4bar injectors? if this is correct then doing the math with your 2000vette injectors are rated at 24/lb @ 55psi while in a car with 43.5psi i get 19lb injectors. (24 x 43.5 / 55 = 19lb) too small for a 383. correct me if im wrong on your set up though.

AtomicTruck

In my opinion, you won't notice any difference in power by only changing the in jectors. The ecm will try to make the system produce the proper amount of fuel either way. Bigger injectors will be ABLE to produce more fuel to produce more power but the engine must be able to produce more power which would demand more fuel. Fuel injectors alone don't make more power.

Part of the thing with the injectors is to make sure the wire connectors are the same. Some of the newer ones have a different connector... You can call the guy at fiveomotorsports and ask. He is real good to work with...

To get more power you will need to upgrade a series of components that make the engine "system" more efficient. Parts need to match, better intake needs better exhaust (headers). Some of the parts mentioned above will definitely help but you need to be aware that longer runners will also change the rpm range where the power is made. So some of it depends on how you drive the car.

By the time you buy injectors, your $725 balance will only go so far. If you are a good mechanic and can shop around, you should be able to find enough parts to make a difference. Or you could stick with stock parts, do a full tune up, change the tranny fluid and start saving for a new set of shocks and tires.

ROCITUP

I DONT HAVE THE EQUATIONS BUT WHEN I RESEARCHED IT I READ THAT WITH ABOUT 46 PSI MY INJECTORS WOULD SUFFICE MY STOCK TPI SET UP ON A 383. IT IS ON THE THRESHOLD THOUGH AND I DONT GO LEAN THE WAY I WAS WITH STOC INJECTORS. NOW I REALLY BABY THE CAR AND ONLY DOG IT SOMETIMES BUT I ACTUALLY FELT IT RUNS FINE EVEN RICH SINCE I HAD TO BACK DOWN PRESSURE FROM 50 PSI TO 46. THEN AGAIN ALL MY LIFE IVE TUNED CARBED CARS BY EAR. BUT I AM RUNNING 'BOUT 46 PSI WITHOUT HANG UPS. PLEASE CHIME IN THOUGHTS ON THIS...THANKS FOR THE MATH IT IS THE ABSOLUTE PROBLEM SOLVER.

QuickStyle

you take the lph rating on the injector and multiply it by what fuel pressure you are running at then divide by what fuel pressure the injectors are rated at to get your correct lph rating.

seeing as you are running a stock tpi intake system on a 383 your power band is really low. and with those injectors in there it is probably running lean during engine warm up and WOT. while at normal operating temp your maf and ecu will compensate for the correct amount of fuel to give the engine which will make your BLM's off. and your injector duty cycle is probably really high. with your set up i would imagine that your engine would lose power after 4500rpm if even that high.

ROCITUP

HEY MAN THANX FOR KNOWLEDGE I KNOW THAT THE 24'S WOULD HAVE BEEN MUCH BETTER, BUT I DID NOT HAVE ENOUGH CASH FOR NEW INJECTORS AND THE REAL PROB IS GETTING SOMEONE TO REPROGRAM MY RIDE. MY INJECTORS ARE PROB WORKING AT 90% DUTY CYCLE BUT IF THEY CAN LAST TILL '09 ITS COOL. THE NEW CAMARO IS OUT......ITS ON. BUT REALLY REPROGRAMING IS THE REAL PROB SINCE I USE THE CAR DAILY I NEEDED IT UP AND RUNNING. BUT IT WILL RUN STRONG AND BURNSOUT SEEMS REALLY FINE.

ROCITUP

HEY MAN THANX FOR KNOWLEDGE I KNOW THAT THE 24'S WOULD HAVE BEEN MUCH BETTER, BUT I DID NOT HAVE ENOUGH CASH FOR NEW INJECTORS AND THE REAL PROB IS GETTING SOMEONE TO REPROGRAM MY RIDE. MY INJECTORS ARE PROB WORKING AT 90% DUTY CYCLE BUT IF THEY CAN LAST TILL '09 ITS COOL. THE NEW CAMARO IS OUT......ITS ON. BUT REALLY REPROGRAMING IS THE REAL PROB SINCE I USE THE CAR DAILY I NEEDED IT UP AND RUNNING. BUT IT WILL RUN STRONG AND BURNSOUT SEEMS REALLY FINE.

QuickStyle

ls1 injectors are 24lb 4bar injectors. you would be better off getting stock 350 injectors or even 305 injectors rather that the vette injectors. your best bet would be to get 24lb svo injectors or if you upgrade your intake then the 30lb's would be better. but if you are just hopeing they will last for a while, then best of luck to you.

and btw.... the burnouts are from low rpm, you will lack upper rpm performance with those injectors.

ROCITUP

I DONT KNOW HOW TO POST OLD THREADS YET BUT WHEN I SEARCHED I FOUND SOME DATA FROM RICH AT CRUISIN PERF., THAT SHOWED MY INJECTORS BEING ABOUT 22.9 LBS ON THREE BAR.