Ok I'm still in the process of installing everything but I'd like to know if others on here have had any difficulty tuning said combo in. I have talked to others through PM's but I'd like to start an open discussion about this because I see it becoming more of a popular swap for us 305 guys. So where should I start? Does anybody have any old ZZ4 timing table that can be used? I'm thinking about staying with the 55lb injectors but kicking up the psi to about 22-28 due to what the EBL utility tells me to get the horse power I'm looking for. 1hp for every cubic inch so do the math,lol. So lets have at it, any thoughts?

 

you will never get the thing tuned if you don't stop changing parts so much

Get the heads ported and then have them bench flowed. After that, use the numbers and all other info like gears, weight, etc and talk to a cam company to give you their recommendations. Once you have a cam, you will know the power band and how much cfm the tbi needs to be. Then bump the FP up to what you need it to be, and maybe add a VFAPR to help with dropping FP at idle so injs are at a good spot if the duty cycle.

Man, have to say I am impressed with all that ya have done. You started tuning right after I got my EBL. Ya probably know more about it than I do. Keep us posted!

 

ZZ4 are fast burn aluminum right? I would use an iron Vortec table to start with.

Comp Cams XE 262 H. Hydralic flat tappet computer cam 218/224 @ .05 114 LSA

 

The heads already have a mild port on them but I never got a chance to get them flowed. As for a cam the ZZ4 is already in,lol I'm telling you, getting the timing cover back on was a bitch!!!

 

These values work with the D port '113 heads. Which GM used on the ZZ4 engines. Although there is a slightly different head that was used on the earlier engines.

The latency table is for the GM 369 (396?) ignition module.

RBob.

 

Hey Bob, what's the part number for that module? I like where this is all heading, let's keep it going.

 

To make timing cover R&R easier on a small block you can take some tin snips (or better yet a dremel with a metal cutting wheel) and cut the ends of the inner flange that go around the front pan gasket off at a 45 degree angle.
When you re-install the cover (with the pan still bolted firmly in place)you insert the bottom of the cover first and then roll the timing cover into position while pressing down firmly. Use LOTS of sealer in the corners.
An old circle track racer showed me that, and I used it many times to do driveway cam swaps without crawling underneath to loosen the pan. Not "proper" but it works. I've had about a 80-90% success rate of not having leaks this way.

 

Full part number is: 16139369

Although, from a 'net search it looks like it has been superseded with this number: 19179578

What I do is to walk through a u-pull-it yard and check the trucks. The module will have '369' stamped on the top. The other 4-digit number is a date code.

Only takes a few seconds to pop the distributor cap off and check the module number.

Picture of the module showing the numbers here:

https://www.thirdgen.org/forums/diy-...ncy-table.html

RBob.

 

Ok everything is up and running and the car sounds mean!! Anyhow, What initial SA should i run? I set it for Zero and the idle sounds a little sluggish. From what I guess from searching is around 5.98 is good. I advanced the timing with the ESC disconnected to 4 and it seemed to run better but I set it back to zero to be safe. What do you guys recommend?

 

Base timing setting is only for cranking and limp mode. Engine running timing is to be set in the calibration.

RBob.

 

ok, should I leave it at zero? I'm not quite understanding?

 

Good job. Sounds mean, even better.

If it runs, 0 is good.

If you add 4° at the damper, then set 4° in "initial SA" calibration it will result 0° advance at idle.

If adding 4° in "SA-Idle State SA", the idle will have 4° more SA. This is probably were you could need the added SA you describe.

Under load use the main SA table.

 

Well I bumped up the timing to 6 advanced in both the balancer and the EBL and the car seems to be ok. As I thought the car most definitely needs some VE learns, it's loping like a beast and i'd like to calm it down a touch through tuning. here's some datalogs of what I have so far. I installed some 61lb injectors and set the BPC to 86 per the utility for 25psi. I don't think my current spring can handle it so I might get one from TDS this week. I noticed that the car has begun to surge after a couple of learns. I thought I had Asynch disabled but when I look at the WUD the car is going into Asynch. Tell me what you think

 

Ok I have a quick question

In regards to these 2 tables How do I set these up for sure?

DGB Injector flow scalar

INJ MPG injector flow constant

Do I just input the Size of the injector or do I input the size of the injector at it's current psi?

 

To set up for different flow rate injectors https://www.thirdgen.org/forums/post...012-post4.html

 

It appears scaler is a relationship between CID and injector size/flow rate. Set it forget it. Injeector flow constant is for the MPG feature on WU.

I found this:

My friend found some 454 injectors before the ECM got back from socketing. It should be here monday or tuesday.

From the website above, the injector flow rate is 80.51# an hr, so what I came up with on the BPWC was 118.

BPWC=Scaler* (cyl vol/ flow rate)
Scaler=1461.5
Flow= 10.144 gms/sec
Cyl Vol=819353 L

If all want to double check and make sure that's right, please do so. Now any tips on the first thing I should be looking at when we begin the tuning on this car that I might overlook. I'm hooking up the wideband and going straight to the v/e tables.
Thanks

 

Well I guess I set it up right



DGB Injector flow scalar 60.47 (rounds off from 61.00)

MPG INJ Flow Constant 79.65 (due to what the utility says for rate per psi)

And if I hope I set this up right, Thomas I actually copied and stored that same "calculator" last night through searching,lol

61/79.4 = .77

so hopefully I can get this thing to run alittle better. it's being a beast to tune at this moment. How do I adjust cruising pw?

 

If replacing #55 with #61 injectors @ 25 psi FP, 55 / 84.6 = 0.65, if I understood right.

I never changed "DGB Injector flow scalar" and "MPG INJ Flow Constant"

Looking forward to learn something new.

 

Sorry I forgot to mention that I changed my psi to 21. What would cause surging? I know I have alot of learns I need to do but it's pretty brutal. It mellows out for a bit but comes back. Here's a little datalog to show you.

 

surging where? idle? cruise at 60 mph?

 

Everywhere, idle and cruise. If I give it a little gas it kind of clears up but it's still there.
it doesn't seem to want to clear up even with learns.

 

If during cruise in closed loop you can rule out fueling. Some say surging is lean and that could be the case at idle if in open loop. I would remove some timing in those cells you see the surge and then smoothen the table. Disable asynch if you have adequate fueling WOT. Moving in out asynch may cause a surge.

 

DGD Injector flow scalar, is only for digital dash cars. As noted in the doc's.

MPG INJ Flow Constant, is only for the WUD Trip display, as noted in the doc's.

Surging is due to a lean condition.

RBob.

 

Really? So how does the EBL know what size injectors it's running?


Also I've been playing with my Open Loop AFR RPM&VAC Tables since I only run in open loop and I would like some opinions, how does this look for the table?

80 70 60 50 40 30 20 10 0
6375 12.80 12.80 12.80 12.80 12.80 12.80 12.80 12.80 12.80
6000 12.80 12.80 12.80 12.80 12.80 12.80 12.80 12.80 12.80
5600 12.80 12.80 12.80 12.80 12.80 12.80 12.80 12.80 12.80
5200 12.80 12.80 12.80 12.80 12.80 12.80 12.80 12.80 12.80
4800 13.00 13.00 13.00 13.00 13.00 13.00 13.00 13.00 13.00
4400 13.50 13.50 13.50 13.50 13.50 13.50 13.50 13.50 13.50
4000 13.80 13.80 13.80 13.80 13.80 13.80 13.80 13.80 13.80
3600 14.00 14.00 14.00 14.00 14.00 14.00 14.00 14.00 14.00
3200 14.10 14.10 14.10 14.10 14.10 14.10 14.10 14.10 14.10
2800 14.20 14.20 14.20 14.20 14.20 14.20 14.20 14.20 14.20
2400 14.30 14.30 14.30 14.30 14.30 14.30 14.30 14.30 14.30
2000 14.40 14.40 14.40 14.40 14.40 14.40 14.40 14.40 14.40
1600 14.50 14.50 14.50 14.50 14.50 14.50 14.50 14.50 14.50
1200 14.60 14.60 14.60 14.60 14.60 14.60 14.60 14.60 14.60
800 14.70 14.70 14.70 14.70 14.70 14.70 14.70 14.70 14.70
400 14.80 14.80 14.80 14.80 14.80 14.80 14.80 14.80 14.80
0 14.90 14.90 14.90 14.90 14.90 14.90 14.90 14.90 14.90

 

RBob how could he be lean if he is in CL running at stoich?

Maybe BLM pegged to max at 160?

EBL knows the injector size. BPC is how...If you use a VAFPR likewise it can use the appropriate BPC in VAC table

 

Actually Ronny I only run in open loop.

 

Subscribing. Cant wait to see how this turns out! Good luck on the tuning.

 

Well I got lucky and decided to use some VE tables I got from BronYur and it's gotten me into the ballpark somewhat. It was REALLY rich but smooth. (sounds like a pudding commercial,lol) I'm almost done leaning it out abit by trimming down the Open Loop AFR vs CTS table. Once I get that closer, I'll start with some more VE learns to try to dial it in a bit more. I'll tell you what even on this weak tune it pulls MUCH harder than before. I can't wait to get it finished.

 

ok it's been awhile since i've posted anything up but i have a couple more questions.

I have since added an Edge 3200 stall to the mix, what can i do in the tuning department to utilize it more effectively?

I'm running PIG rich in the WOT area. like 10.5-11.2. Do i have to reduce PE or would it just be better to lower the VE in those areas? Plus I'm wanting to play a little more with the timing to see if I can get all I can out of this engine before it gets swapped out for the LT1 383. (Hell I figure I've been working on it this long I might as well finish it)



I know my car LIKES to run a little fat. It doesn't seem happy unless the AFR's are like 13.7 0r a touch lower.

 

Maybe, add some SA in the SA-launch for the converter.

I vould reduce VE, if still too much fuel reduce fuel pressure.

 

If you are locking out CL and running exclusively OL how do the VE tables come into play?

I dont think VE tables are used unless you simulate NB with a WB in place of. A good reasonto use CL as well as gas mileage considerations.

 

The VE tables are always in use.

RBob.