Injector Size
Thread Starter
Racer
Joined: May 2004
Posts: 476
Likes: 0
From: DFW TX
Injector Size
Getting ready to start my tear down on my 86 L98, wondering what size injectors you guys are running or recommend with 6 to 8psi of boost without using a FMU on a supercharger (SN93 Paxton). Would 42's be about right?
Here is the basic's of my setup.
Superram manifold, plenum & runners
214/224 112LS flat tappet cam & 1.6 roller rockers
Stock alum. heads with 2.00/1.56 valves, double springs and porting
fuild damper/true roller timing chain
52mm throttle body
Headers/high flow cat/catback system
2600 edge stall
MSD 6AL
Tuned on dyno
Here is the basic's of my setup.
Superram manifold, plenum & runners
214/224 112LS flat tappet cam & 1.6 roller rockers
Stock alum. heads with 2.00/1.56 valves, double springs and porting
fuild damper/true roller timing chain
52mm throttle body
Headers/high flow cat/catback system
2600 edge stall
MSD 6AL
Tuned on dyno
Pro
Joined: Jan 2004
Posts: 503
Likes: 0
From: Forney Texas
Your setup is very close to mine. I have been consulting with Greg @ Blowerworks and he recommended going with 24# injectors. As I have retained the stock ECM, I was told it could not handle injectors any larger than 24# and this size injector would meet my requirements.
I have not gotten everything ready to run so I can't give you first hand info. I can only give you the advice of a guy who has been running this type of mod for quite some time and has nothing to gain by recommending the 24# injectors if they are not going to give the performance the system is designed to produce.
Good luck.
90Indy
I have not gotten everything ready to run so I can't give you first hand info. I can only give you the advice of a guy who has been running this type of mod for quite some time and has nothing to gain by recommending the 24# injectors if they are not going to give the performance the system is designed to produce.
Good luck.
90Indy
Melting Slicks
Joined: Dec 2000
Posts: 2,719
Likes: 60
From: Fremont Oh
Vetster 86,
wth the 24's you will need to use an FMU. Your clculations are correct ( 42#) but I've been also told it has to do with the way the injectors "fire". You would also get better atomization of the fuel running a smaller injector and higher fuel pressure...
I also agree check with Greg, he will not steer you wrong...
My $46 dollars
Mo
wth the 24's you will need to use an FMU. Your clculations are correct ( 42#) but I've been also told it has to do with the way the injectors "fire". You would also get better atomization of the fuel running a smaller injector and higher fuel pressure...
I also agree check with Greg, he will not steer you wrong...
My $46 dollars
Mo
Thread Starter
Racer
Joined: May 2004
Posts: 476
Likes: 0
From: DFW TX
I'm already working with Greg from Blower Works on some other things.
I'm using a FMU on my 94 supercharged Camaro, to me the FMU is just a bandaid for tuning and they can fail. The stock ECM should handle up to about a 50lb injector with the right tuning. To much pressure on small injectors can cause them to lock at wot. Just wanted to know what size injectors others are running without using a FMU.
I'm using a FMU on my 94 supercharged Camaro, to me the FMU is just a bandaid for tuning and they can fail. The stock ECM should handle up to about a 50lb injector with the right tuning. To much pressure on small injectors can cause them to lock at wot. Just wanted to know what size injectors others are running without using a FMU.
Melting Slicks
Joined: Dec 2000
Posts: 2,719
Likes: 60
From: Fremont Oh
ok i thought you were talkng about a 86Corvette, I agree on a 94 yes you would be at about 42 pounds, I'm running 36's...
You could also talk to Greg about his superpumper.
Yes depending on the type of injector you are using pintle type injecotrs can handle higher pressures...
Mo
You could also talk to Greg about his superpumper.
Yes depending on the type of injector you are using pintle type injecotrs can handle higher pressures...
Mo
Thread Starter
Racer
Joined: May 2004
Posts: 476
Likes: 0
From: DFW TX
I am talking about my 86, I was thinking of using the Ford Lighting green top 42's. I don't see why my stock ECM wouldn't handle them with the right tuning. I'm tring to get away from using a FMU like I have on my 94 Camaro.
Intermediate
Joined: Apr 2000
Posts: 47
Likes: 0
From: Woodstock IL
Originally Posted by vetster86
I am talking about my 86, I was thinking of using the Ford Lighting green top 42's. I don't see why my stock ECM wouldn't handle them with the right tuning. I'm tring to get away from using a FMU like I have on my 94 Camaro.
Only issues I see is the MAF of 255gsm limit and lack of ability to sense a rise in boost pressure. Running a piggy back injector system would be the next best options such as the ones offered by aquamist or blowerworks. Followed by changing to a different ecu code. In keeping with the 165/808 ecu you could run the $5d code from down under and split the ve tables to handle 2 bar map or change the ecu all together. The 7749/7730 ecu with $58 or $60 code both can run a 2bar map and can be adjusted to operate up to 3 bar sensor.
ps
Don't forget to address your fuel pump.
Thread Starter
Racer
Joined: May 2004
Posts: 476
Likes: 0
From: DFW TX
Originally Posted by ED89
Only issues I see is the MAF of 255gsm limit and lack of ability to sense a rise in boost pressure. Running a piggy back injector system would be the next best options such as the ones offered by aquamist or blowerworks. Followed by changing to a different ecu code. In keeping with the 165/808 ecu you could run the $5d code from down under and split the ve tables to handle 2 bar map or change the ecu all together. The 7749/7730 ecu with $58 or $60 code both can run a 2bar map and can be adjusted to operate up to 3 bar sensor.
ps
Don't forget to address your fuel pump.
ps
Don't forget to address your fuel pump.
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Burning Brakes
Joined: Dec 2002
Posts: 1,088
Likes: 0
From: Lakeland fl
With your planned mods, your stock injectors- if in good condition should work fine. Ive got an 85, with a 10 lb kit and mine is fine on the WB02 using an FMU and the stock injectors. Now, ditch the FMU and you will need larger injectors and tuning.
*** sorry, I just noticed you said WITHOUT an FMU.
*** sorry, I just noticed you said WITHOUT an FMU.
