New injectors wont do anything.

Maybe you can block off your return line some how and let the thing prime to see if she can even build pressure of more then 15psi. Things I can think of is the FPR not doing it's job or maybe a block in the line or kink, could try blowing out the lines.

 

The lines are only 2 yrs old and look in damn good shape.No kinks in it and I blow them out when I changed the filter and checked the pump.I have an access hold so I can easily change the pump from my trunk.

Ill have to try block the return line and see if that helps hold the pressure.If not..either my pump is lazy or something with the fuel pump assembly is stuck open and doesnt let pressure build.

 

its a new fpr..using the kirban unit.but before that i was using the holley fpr and it was the same pressure but it was an unstabble regulator..the holly would drop pressure sometimes.the kirban unit works as it should so far. Maybe my fuel pump is going...it was a cheap ebay unit.

 

Defiantly sounds like something is going on between the FPR to the fuel pump. Since you have a access hole might be worth it to check the rubber line from the pump to steel line in the fuel tank, could have a crack or one of the hose clamps loose. Could also check your voltage to the pump also if you haven't already.

 

yea i think ill be pulling the pump out again and see if anything is gone wrong..wouldnt be the first time that the pump came off the clamps lol.Voltage to the pump is good..its read the same as the battery on my scanner.but i heard there is supposed to be a check valve somewhere and that it could cause this issue.

 

TPI based systems need 48 psi.
You need a fuel injection fuel pump, not a high performance carburetor one.
Make sure your whole system can handle the (much) higher pressure.

 

15 psi is fuel pressure lowest limit where engine runs.When my camaro pump went bad I check fuel pressure ,and when it goes below 15 psi engine stops.

 

the fuel pump in my car is a whalbro knockoff 255lph for ls1's,lt1's,tpi's and it has been working fine the past year and half. my main concern is that even if the pump was the wrong pump..it does not hold any fuel pressure when you prime the system.it hits 15-20 psi and then drops right to 0.I asked a friend of mine who is a pretty old mechanic and says that he recalls a check valve being in the tank on one of the lines. Told me to pinch the rubber return line just below the tank..then pressurize the system and then turn it back off.If it holds pressure then...then the checkvalve is stuck open.he also thinks my pump has either come lose again and im only getting 15-20 psi because of the pressure in the tank its creating...says its common with cheap parts.Im going to try to check ti out tonight since its nice outside.

 

Knockoff pumps are known to fail. If its not holding pressure, and the injectors are not leaking, it could be a bad valve in the pump and thus the pump needs replaced.

Check voltage to the pump to see if its getting enough. Should see atleast 13 volts hopefully.

 

volatge to the pump is .4 volts off from the battery so its pretty good.what you say makes sense aswell.Sucks that pump decided to fail right after my hsr swap lol...now the question is..how can I verify the valve on the pump is bad..and its not a bad pump assembly?

 

The way you described above is a good indication if you did pinch the line enough. It shouldnt drop down if you pinched off the return line.

 

*I FOUND THE BUGGER!!!*

So after replacing everything under the sun to figure out my fueling issues,it was under my nose the entire time.I got home last night and went to town tearing my trunk apart and took out the pump assembly.Everything appeared to be fine from certain angles anyway. I got smart and said..why not test bench the pump assembly with a bucket of sum fuel and see what happens.

I supply 12v to it and fuel just streamed everywhere but the feed line..well..barely through it..but where the aftermarket pump supplies the assembly,the cheap 2 inch foamy rubber line was gushing under the clamp that wore through in one spot. So I got a piece of high pressure efi fuel line and used steel clamps on it..slapped it back together..primed it and low and behold..25psi..re-primed and then i saw 60psi of fuel and held for 45 mins.I knew then..my 383 was going to wake up for the first time in month of this build.I fired her up and she had alot to say while burning 3rd gear down my street.

Without the advice of all you guys.. I wouldnt have been able to narrow my issues down..all the responses lead me here to a now finally happy 383hsr owner.Now i can do some tuning basics and hopefully my 32# bosch 3 injectors will be on my door tonight and i can slap them in and go for a long awaited cruise.

heres a pic of the culprit.

 

About time you got her running right

Now get us some track times!

 

lol yea its about time.. now i that i can drive it i gotta play with the tv cable..its shifting way too early for my liking..as in..if i punch it while in first..it will shift to second early and feels like the tq converter is on and then pulls like mad haha.

 

yeah id like to see some numbers too (track,dyno,ect) because i have a very similar build as yours and im not too satisfied with it. i can barely hang with bolt on ls1's and bolt on mustang gt's. kinda frustrating if you ask me lol

 

"and hopefully my 32# bosch 3 injectors will be on my door tonight "

Glad you found your problem. I will be running the exact same injectors on my new motor. I have the extended version by FIC to fit my TPI system.

 

I have some bad news for you. It is going to happen again if that is EFI line intended to not be submersed in fuel. You need special EFI submersible line. Regular EFI line in a tank will also deteriorate. Post the SAE numbers for that EFI line you put in the tank.

 

Thats a very good piece of info that I will look into..I very much appreciate the tip.Was not aware that there is 2 types of efi fuel line.Now I know what the problem will be when it does happen.

As for hanging with ls1's and mustang gt's..Im not sure this combo would exactly beat them unless you got a good pair of slicks and run from a dig..but it should surprise them enough to make a interesting race..thats all I can ask for.Now that Ive had my car out for a few lengthy test drives I wish I had invested more in the build but funds didnt permit it.I wanted to port the hsr as much as I could..gasket match everything and step up to the xfi292 cam ...but the xfi280 is just enough to drive easily on the street and have vacuum for brakes.

If you are frustrated with the way yours performs keep digging..maybe something is off..I know mine isnt 100% yet...might never be but Ill keep playing with it for now.I need to figure out why my shift points are off and why the car bogs in 3rd.but for around here..the sound of my car will scare off most of the imports..the domestics Im not trying to even compete with,finding a stock ls1 to run against is near impossible..same for stock mustangs.Your motor does look like quite the show piece though ..I love the polish look..but after having my tpi fully polished..and valve covers...pullies..I like to just hoes the motor down andw wipe the water off the painted pieces instead lol..call me lazy

 

YOur combo once tuned up and running in tip top shape should handle most cars you will come across. Mild cam only LS1's shouldnt outrun you unless they have big cams Even then I dont think they will walk you that hard. LS1 cars arent the lightest cars out there. I know of a few that dyno strong but just dont run the numbers you'd expect.

 

"I know of a few that dyno strong but just dont run the numbers you'd expect.

I have seen that myself. I thought I was the only one.

 

My 383 HSR was outrunning most of the cam only setups that dyno'd as much as me and there is even a heads/cam car that doesnt run on par with the 383 I had. The few guys with 408-440 inch lsx motors around me dont even run that well for what they are. Low 11's at 120-125. My buddy's 406 miniram motor ran 10.6's on motor at 130 and still has more in it. (t56 car haha)

Local texas guy here with a 360" L98 based motor with 280 xfi would kill my bolt on LS1 trans am. His car feels strong and its using old style 190 AFR heads and fairly low compression.

 

Yeah.. cammed ls1 can put down nice numbers..but they are heavier than our cars..Im sure more and more Ill bring out the performance of this build..and the tune seems to be decent for now.Once i think its dialed in enough,Ill be adding my 10lbs bottle of giggly for the "just incase" races I may encounter

http://www.youtube.com/watch?v=QMrdqZXk4N4
http://www.youtube.com/watch?v=lFYIKUH2mkg

 

hi there i also have a 383, afr 195, compcams extreme 08-0408-8 cam, with 10:1 comp,36lbs inj, arizona tpi ecm,headmen elete coated headers, built 700r4 with 2500 lockup converter, 373 motive gears.
i'm having the same problem with this set up. it seems to be low on power bogs down once in second gear. Power surges when lite on the throtle pops throught the exhaust when under load. the fuel pressure is set at 45psi. dont know what to do to fix this problem. I have been thinking of switching over to the ez efi or the ez xfi setup from fast.
You seem to know alot about what to do with these cars. hopefuly you can shed some light on this for me.
oh yah the car is a 1991 z28 1le.

 

Not that Im exactly happy to hear that others are experiencing the same problem but it gives a bit of relief.With my motor as I dig more and more on fine tuning things..I can feel power being brought into life.My biggest issue I see right now are 2 things that would make the ecm pull power all the way through the band.1st is the motor still has knocks from the day it was built so every few seconds...I get a knock count and the ecm pulls timining for a second or so.2nd is that I think there is an air pocket in the cooling system because Im seeing a 40* variance in temp between the ecm reading around 180* and the guage on my dash(factory guage) reading around 140-150* when hot.The car never over heats but sometimes it seems like the ecm thinks the motor is still cold and keeps the idle high at around 1000-1200rpm.I dont exactly remember how to burp the cooling system to make sure its got no air pockets..but my water pump is fairlyy old and maybe its not pumping anymore.Other than that..i think I have chased down everything else in my path aside from having it dyno tuned.

 

Probably tuning issues if you are having some problems with this cam. Its a nice running setup with good valve springs to control the lobes and ona 383 its not too aggressive so it shouldnt take much to get it to run smoothly.

Speed density can be abit more picky to tune but in the end there is no reason that setup should run poorly if all the mechanical aspects are in order. If the motor has a problem, you cant tune that.

 

Exactly what Orr said is true.My car runs fairly smoothly for the pcmforless tune that it has..Im aware of a few snags that will hinder the performance still but I think this combo will be a good street motor to surprise most people for what aged technology is behind it.Its not the TPI torque monster it once was but still has more than enough grunt off the line..makes it easier to hook in my opinion and has the topend to keep up lt1s and ls1 if fully ported etc.

Also Ive noticed a huge difference between using different octane grades of fuel.94+ octane seems to really make the motor run uptop from what I can feel on the butt dyno lol.I used octane boost on a fresh tank of 94 and it loved it..short lived tank of fuel though..cant imagine why

 

I checked the fuel pressure today by priming the system and it doesn't hold pressure unless its running. I don't know if this is normal or not I would hate to have to drop the take to get at the pump to make sure nothing has come loose.
I tried the timing also but I dnt know what the ecm is set at I will call arizona tpi tomorrow and ask.
I set initial at 30* it seems to like that. Total appears to be 45* with or without the ect wire hooked up. That seems is way to high to me.

 

30* Initial timing is way too high. first off.Find out what the ecm is set to for base timing..it will be around 8-12* would be a safe guess.And the car should hold pressure just turning the key on without starting it,if not then you have a problem somewhere..mine was right in the tank..hopefully you have a leak elsewhere but dig deep to solve this since its a vital function.How much pressure do you get with it running with the vacuum line disconnected?