L28e turbo w/76 ecu &stock injectors need help

[BrandonR.]

Hello I need some help. I have a n42 block, Dished Pistons, with n47 head, currently running a 1976 ecu,harness,& 188cc l28e injectors. Also have a bell adjustable rising rate fuel pressure reg. set to about 38psi and about 65psi at the rail WOT 4.5psi on the boost gauge

 

I dont have a wideband setup yet and will start building MSnS over summer.

 

The problem I have is I dont feel safe with the set up it does have a turbo AFM and a 280zx dizzy not from a turbo car. Also has the vac.advance.

 

I drove from california to ny with no problem purrs like a tiger so please dont post this setup wont work lol

 

I have the 260cc turbo injectors I would like to install so I dont run lean and pop a block while in boost but she runs piss rich.

Other than scrap my whole efi right now is there a way to lean out the turbo injectors using the turbo AFM and FPR eventhough im running a 76'ecu

Thanks,Brandon

Edited April 28, 2012 by BrandonR.

[Vonlam43]

Try adjusting the spring inside the afm

[BrandonR.]

Thanks ill read some more posts about that and and turbo injectors on 280z ecu

Edited April 28, 2012 by BrandonR.

[BrandonR.]

Thought about doing that but if I throw the bigger injectors in running 65-68psi at wot wouldnt I run rich even with that adjusted.

 

What are my chances of detonation with the small188cc injectors at 38psi idle & 69psi wot.

 

My distributor from what the PO told me was from a 280zx has a vaccum line running to it im assuming for advancing timing. Will this distributor damage my engine by not retarding the timing like the CAS based zxt distributor

 

Reason I ask is 5lb/boost is ok but iv had a electronic boost controller in it for a while only have not touched it after I found out what ecu it had along with it being a non turbo engine. I just want to bring it up to the stock 7psi of the l28et once I get a wideband installed but not if it blows my engine.

Sorry for all the questions im using a phone and im running low on phone time also hard to find similar engine setups that have not alreasy swaped to megasquirt or used the zxt ecu and harness

[NewZed]

I've seen a common recipe over on zcar.com for using the RRFPR with a turbo. It involves locking the timing on the distributor and using the RRFPR to dump fuel to prevent self-destruction. Crude, but apparently boost happens and the motor lives. You might get more help over there.

[Pyro]

I have been running a similar set up for 6 or 7 years now. Completely Stock 76 efi with a bell fmu and locked out stock ignition. But I use to 10-14 psi of boost (adjustable) and 28 degrees of timing with 7.4:1 cr and a NA cam. This requires a good efi pump (like a bosch 044) and 80 to 110 psi of fuel pressure (8:1 fuel pressure/turbo boost).

 

With the stock NA setup (8.3;1 cr) you can run around 24 degrees of timing with 7 to 8 psi of boost and 65 psi of fuel pressure. Use the vacuum advance as normal. FYI, stock turbo ignition timing is 24 degrees at idle.

 

In your case, I would use a P90 or P79 head to lower compression to 7.4:1 cr and use 8 psi of boost with 30 degrees of timing (locked out), and 65 psi of fuel pressure.

 

You need to pull out the distributor and disassemble until you get down the the mechanical advance slots. Once you get there, lock out the advance (rtv in slots, wire instead of springs, welding, lots of ways to lock it out).

 

Megasquirt is a much better way to manage a turbo setup but the fmu and locked ignition works OK with stock boost.

[BrandonR.]

Thanks for all the advice! I've looked in to locking the distributor some. Were you using the 188cc intectors or the 260cc ones.

Will 7-8 psi feed the 60mm TB thats on it, i think the fmic piping is only 2.25" & 3" exhaust

Also is that 24 deg. timing before of after TDC

 

 

Ill look in to a p90 after I swap the ecu but if i can find one id rather throw in the whole engine and run edis

[Pyro]

I'm using totally stock 76 efi and ignition. That includes the smaller NA injectors. No wait, that isn't totally true. I recent changed the stock fuel pressure regulator out for a Aeromotive fpr because the stock one starting leaking fuel, but I use stock fuel pressure.

 

The throttle body isn't the bottle neck. It is the small intake ports. stock of 60mm TD doesn't make a difference.

 

I'm using 2-1/2 exhaust with 2 inch from the turbo to the intercooler then 2-1/2 from the IC to the throttle body.

 

My car had a 110 mph trap speed in the 1/4 mile.

 

Yes, lock your timing at 24 btdc. Locked means it doesn't move when you rev it up (without the vacuum advance connected). But use the vacuum advance as you would normally.

[BrandonR.]

Nice (im about to check but do you have a build thread at all). I have one drag slip from the previous owner from 05 before the turbo swap ran a nice and slow 15.004 at 88.83 mph : D id like to see something better than a 15...im guessing your somewhere in the 13.5 ish area

 

 

When you say to lock the advance then to use it normally what do i do, lock it or leave it? Time to dust off/find my timing light

 

Thanks for the help though. I dont feel like my car has a bomb under the hood anymore : ) but ur 110mph compaired to my 88 mph..damn.. :-[ might be a little quicker now after the turbo swap but i wouldnt hold my breath.

[Pyro]

You need to open up the distributor to get to the mechanical advance slots and springs. Pull off the rotor, Pry off the star on top, pull the top plate, then you can see the springs and slots. Then you could take the springs off and use wire in their place, and maybe some rtv to fill in the advance slots.

 

Set the timing at idle to 24 degrees. Use 7 psi of boost with 60 to 65 psi of fuel pressure at full boost.

 

Then use the vacuum advance part of the distributor like normal. The boost will shut down the vacuum advance.

 

Should be able to hit 100 in the 1/4 mile with 7 to 8 psi of boost and intercooler.

[BrandonR.]

Iv got you all the way up to the using the vacuum advance as normal.(iv locked a distributor before so i know what you want me to weld/glue)

 

If i weld those weights in place wouldnt that make the vacuum advance part not function anymore. Making it useless to keep connected. Sorry for any ignorance im not too familiar with vac. advance distributor iv only played around with a GM distributor that only had mechanical advance

[SleeperZ]

No, locking the weights disables the centrifugal advance (mechanical advance with RPM). The vacuum advance is separate, and advances the timing with lighter load.

Edited May 1, 2012 by SleeperZ

[BrandonR.]

Thanks i finally found a post by pyro from 05 describing it i didnt know it had, mech. advance and vac. advance i understand a little better now just had to hit my head with a hammer a few times to get the brain cells firing again : )

 

 

just to be safe one last group of questions. If the mechanical advance goes by engine rpm and counter weights. What does the vacuum advance control i dont want to accidently lock that out(if possible)ill do more research you dont have to answer that . As log as all i weld are the mechanical advance "arms" i should still have vacuum advance correct.

Im grateful for all responses Thanks everyone for dealing with me. Had the car had the proper l28et & ecu swap i might not have learned something!

[ctc]

Research the Euro spec turbo cars. I believe they use a vacuum distibutor. There have been a couple threads on here about it or mentioning it.

[BrandonR.]

Lucky Eruopeans cool setup on that dist.

 

My distributor was already locked timings at about 24-25deg

wish i didnt have to travel 10miles to work on the the thing could have known last time i messed with it a week ago and saved a bunch of ppl trouble.

 

Is it all good to set my low and high boost setting on my controller to 7&10 or 7&9psi i dont need 10psi right now ill wait untill i get the rest of my gauges together for that