I need a some help deciding on my new project build on which direction to go on the FI system for my new 383 510hp (not installed yet).
Right now i have a mild 350 TPI with #22 injectors with 58mm TB with the stock ECU (stage2 chip from Harris Performance)
the questions is, should i stay with the TPI system or go with a Stealth Ram, or even the Pro-Flo 4XT Kit using Edelbrock's ECU system with the new 383 motor?
I've read that the TPI makes decent numbers on 383's but can have it's issues due to the long runner design.

I'm leaning towards the Pro-Flo 4 XT Kit (below) but would like to hear from you guys on your 383 EFI build
https://www.summitracing.com/parts/edl-35810


85 IROC, Full Spohn Suspension QA1 Coil Overs, Long Tube Headers, 700R4 2400Stall

 

I'm no aficionado but from what my reading has found, I'd never turn down a stealth ram for a port injected sbc unless I really care more about midrange torque than actual hp. Especially on a 383. If long runner, dump the factory style base and go to a FIRST. Mini ram for max HP or more cubes. The proflo doesn't get much attention. When it does it seems to need more work than it's worth compared to other manifolds. Not saying it can't be a good manifold but it wouldn't be on my radar.

Being you have an 85, I wouldn't use the original ecm in any fashion but if you keep the electronics use EBL-P4. If you want to redo more and have a newer interface etc, I'd look into Holley efi. I have no personal experience but it seems to be the go to system for people that know their stuff. That might not be the choice I make at the end BUT I would look deep into it.

 

I love me some shorter runner intakes to maximize power. Stealth ram with a holley efi ecu would be the best. Or a single plane efi with the same

i dont know anyone using Edelbrock ecus. The intake would be good but rather see it with some form of holley efi ecu

 

Appreciate the feedback
Maybe i go with the HSR intake and fuel rails with #36 injectors, seems like a good price point for just the intake and rails.
would i benefit if swap to a 90-92 TPI ECM # 1227730 w/matching harness and run the EFI in that manner instead of the old 85unit?

Reason i like the Edelbrock Pro-Flo is, one it's a complete kit (ECM, injectors, disty, manifold, TB, etc...plug and play.), seems like a pretty straight forward install.
Second is the price point, there's no other EFI system that includes all this for around $2K, not unless you start mixing parts which im not i want to do.

Even if went with the new 90-92 harness+ECM, #36 injectors, HSR intake, new small cap disty, and tuning, that will still total around or above $2K

If i go aftermarket, say the HSR ECM, how do you control the TCC lockup on the 700r4...assuming an aftermarket controller as well or tog switch?

 

Larry’s electric has the sd harness, ebl p4 or I have used 730s.
hsr new I think is $700. I’ve tuned the 165 if you upgrade to that a 425 hp engine but the maf is a restriction.

 

i like the idea of the 730 w/ HSR and Larry's pricing is not bad compared to the Painless kit.

how much do you want for a used 730 unit (i'm seeing them go for $50-100 online)?
my 383 build is 510hp crank so MAF is probably not a question if i stay stock ECM's.

 

$65 shipped in the states for a used 730, I have a few choices for memcals at a extra price.
would want to get some equipment from moates.net about $200 for everything you need.

 

Any idea what vacuum you will have at idle ?

 

Yeah dont use an 85 setup. Go 730 or later 165 with 6e but rather go speed density

holley efi you can setup and output to activate lockup. Simple speed switch or get creative with tps % and speed. Theres ways to do it im sure

 

And yeah even the terminator 4bbl kits are 2300 ish. Holley hp stealth ram or single plane kit is 3400. Holley hp with 4bbl for carb manifold retrofit is 2800 ish and run a manifold of your choice

 

I do not, the motor is still in the build stage, what factor would this vacuum play part of in EFI?

 

seems like a good deal, i will PM you if i decide to buy it 730unit
i'm going to contact Harris Performance about the memcal since i purchased my 85 chip from him, i believe he will let me swap them for a low cost difference.
i will also check out moates
thank you!!

 

i think i will go 730 speed density + HSR intake only, and try to keep this "original" and burn a custom tune.
HSR full kit $3400 is high but considering its a complete kit t's not a bad deal, i think i can get this done for about $2K or right around that number using a 730 ECM
i already have a 58mm TB so that saves some $$.

 

Unsteady manifold vacuum or anything below 14hg is a bear to tune. Although I’ve done one engine with 10hg at idle . Had to force open loop and idle wasn’t quite right but ran decent otherwise . Orr May have some suggestions as well.
Can always rework the 870 85 harness to save some. I think I have some 730 ecm pigtails. The complete hsr is insanely priced. There is a used hsr in the classified section or the weiand isn’t to bad price wise it’s the rails that are the expensive part.
If brian Harris does exchanges you might ask if the 730 memcal is a v6 or v8. The v6 conversation ones don’t have a functioning knock sensor if that matters to you. Some sell these and don’t change cylinder select so they never run quite right like Jim’s performance.

 

You certainly don't need to buy a new HSR. Plenty out there. Even a few in tgo classifieds right now. Example https://www.thirdgen.org/forums/engi...am-intake.html

 

Short runner manifolds are interesting to tune for accelerator enrichment...

What you may want to do if you go 7730 is start with my Miniram start bin. Other people have used it and said it got them pretty close as a good starting point to dial in the rest.

Email me at ultm8z@yahoo.com and ill send it to you.

 

Larger overlap low vacuum at idle cams can be tricky. I think folks expect it to run like stock but that’s simply not the case. With 730, it is definitely a good idea to disable closed loop until like 1200-1300 rpm. Let your idle end up around 900-1000, some guys dont like going that high but faster idle will stabilize easier and make more vacuum for power brakes. A good 500 ish hp cam will have enough overlap to be good at 900 rpm. I liked locking timing out around all cells in which it may idle, although some tweaking there can help produce stabilizing effects but too much can cause surging of rpm.

it takes some time to perfect it depending on your preferences and expectations and near impossible imo to do without being there in person to mess with it. You can get close over emailing tunes and logs. I really like code with closed throttle fuel and timing tables for more resolution and fine tuning. I’ve run some nasty stuff on 730/59 stuff. And my buddy had a pretty nasty 406 miniram on 730, enough cam to go 10’s on motor so it can be done

 

----TUNED PERFORMANCE---
are you in Colorado?
if so, i live near the denver area, maybe once i get this motor in can you burn me a custom tune?

 

from everything i'm reading i think im headed in the 730ECM with a new harness and some small add on goodies below:
Probably going with with the Weiand ]Stealth Ram+Rails setup (might pull the trigger on that used unit today):
#36 injectors
Wideband (i already have the 3w heated O2)
Speed Sensor 4000pulse
Small Cap w/remote Coil
Moates (maybe)
... anything you think i might need to get this party started?

say by by to the TPI, she's been a fun ride while it lasted ;-)

 

just sent you an email

 

Download Tunerpro and get the S_AUJP v6 to start with in order to get the .xdf and .adx files. Extra goodies in there over the standard AUJP, including the features necessary to log WB data. Do a search for S_AUJP v6 and look for the thread started by 84Elky.

You'll also want to run a HEI module test to validate how your ignition module handles spark latency before doing any tuning as well. Start at post #54 and go from there...

https://www.thirdgen.org/forums/diy-...y-table-2.html

If you run a factory AC Delco ignition module, chances are it's correct (when ran the test with a Delco, it was pretty much spot on). But anything non-factory, I'd run this test to verify... you can see how far off my aftermarket ones were.

 

Thanks, will do, i have some serious learning to do when it comes to tuning since i'm new to this side of the build spectrum.

 

I’m in Cotopaxi,co so alittle ways away. I haven’t tuned live in awhile but can help refine with datalog tuning.

 

i will keep that in mind when things get closer to that stage

 

What do you guys think about the Holley Sniper EFI system?

My 383 is coming with a single plane intake so maybe i just take advantage of it and do a 4bbl EFI conversion, much lighter on the pockets too.
https://www.holley.com/products/fuel.../parts/550-511

 

The TBI style EFI systems probably aren't as good on throttle response and driveability as a true port EFI set up is.

But, if the ECU has self-learn capability and is more user friendly than a 7730, and you're completely new to tuning, there may be an advantage for you on using that system.

 

I'm also going to be sending you a spark latency test bin. Every spark parameter is set to 20 deg. In the link I posted earlier, use this bin to check your ignition timing per that process. Don't unplug your EST connector to run the test though.