383 TBI buildup, lots of pics!

[billvill]

A couple of questions ?

Roller rockers are all over ebay for about $160.00. I have had the Crane golds years ago for another truck and actually transfered them to the 383 that replaced that 350. They had very little signs of wear after 60k of miles I paid $325 back then. (1995 maybe) I really don't see a sinificant difference between them and the no names i just purchased. Why didn't you go for the roller rockers. Maybe I am just getting cheap in my old age. Or don't you trust the up and coming small parts manufactures.

I see aluminum water pumps all over ebay as well for $50.00. I read the guys statement who makes them and I think they look good. That iron pump weighs a ton. Why ot go that way over the iron pump.

Just curious Billy

[billvill]

A couple of questions ?

Roller rockers are all over ebay for about $160.00. I have had the cranes years ago for another truck and paid the $325 back then. I really don't see a significant difference between them and the no names i just purchased. Why didn't you go for the roller rockers. Maybe I am just getting cheap in my old age. Or don't you guys trust the up and coming small parts manufactures that get national advertisement on ebay.

I see aluminum water pumps all over ebay as well for $50.00. I read the guys statement who makes them and I think they look good. That iron pump weighs a ton. Why not go that way over the iron pump.

Just curious Billy

[ImpalaGuy]

UPDATE: THE 383 IS (finally) IN!

I actually started the install two weekends ago at my friend's shop and buttoned it up a few days ago. The main reason it took two weekends was because the machine shop gave me crappy advice. He wanted me to buy a flexplate to balance the rotating assembly, and I said "I've got an LT1 one here, will it work on the truck?". He assured me it would. Well, as you can imagine, he was wrong. The truck takes the larger diameter wheel vs. the smaller one on the LT1s. I didn't know it until the new motor was installed, buttoned up, fluids topped off, and I turned the key. The starter spun in open air. We called it quit for the day.

So last weekend I pulled the tranny, replaced the flexplate, and bolted her back up. Fired up on the first try! Adjusted the timing and valves, did my best attempt at a program and took her home. Here's some pics...

I mentioned my friend's shop. His dad owns a 1000 acre cattle farm here in the hills of Kentucky and built a BEAUTIFUL equipment shop a few years ago. It's over an hour away but it's heated and has LOTS of space. An absolutely wonderful place to wrench. That's my buddy Chris in the pic -- I owe him a big thanks for his help and use of his shop. Check out the pic...



Here's a shot of the engine compartment with something missing...



And here's a shot of the new 383 and the old 350 on stands. (Can you believe this shop?)



Here's the motor nestled into position, but not quite ready to fire...




And here's a shot of the motor right now. Gotta love that sexy air cleaner, eh?




I got it running with my own program, but after several attempts I decided I would be better off spending $200 and getting Brian's help at TBI chips. He's been great. We've quickly realized that I need to put a higher volume fuel pump and I need to stay FAR away from full-throttle until then. I ordered it today.

I'll keep you guys posted.

[mrflames]

let us know what kind of power its putting out. when you get it to full trottle. i have a 383 stocker tbi in my truck also. i was glad to see you stayed with the stock tbi. i went with a holley and have had nothing but problems with it.

[jeep45238]

Impalaguy:

Where in KY is the shop/you located at? I'd love to kick back some bewskies and check out your truck, since it's pretty much what I'm aiming for engine wise with mine.

[GMC Sierra]

that thing looks sweet wanna build me one

[ClawSS]

Thanks Ron...It was fun and I enjoyed the time. Maybe now we can concentrate on Dad's '93 3500.

You enjoy and I will look forward to running your '95 383 against my '02 496.

[billvill]

Whats your address and don't lock your garage tonight !

Looks great. Nice combination.

[ImpalaGuy]

Originally Posted by mrflames

let us know what kind of power its putting out. when you get it to full trottle. i have a 383 stocker tbi in my truck also. i was glad to see you stayed with the stock tbi. i went with a holley and have had nothing but problems with it.

Let's take a look here...
Mrflames engine compartment:


My engine compartment:



Man, looks like I need to do some house-cleaning!

I had experience with a Holley throttle body on my Impala. I went from a bored-over stock unit to a Holley one and, like you, had all kinds of tuning problems. So I stuck with the extreme-fi 50mm stock one for the truck. So far, so good.

I got my fuel pump in, now I just need to drop the tank and get it installed.

[GreaseDog]

got a link for extreme-fi ?

[reeder5001]

www.xtremefi.com

[cedjunior]

I had heard that Holley started using Delphi injectors (same ones stock TBI's use) and that solved most of the problems people were having with them. Tuning a separate issue?

[mrflames]

Originally Posted by ImpalaGuy

Let's take a look here...
Mrflames engine compartment:


My engine compartment:



Man, looks like I need to do some house-cleaning!

I had experience with a Holley throttle body on my Impala. I went from a bored-over stock unit to a Holley one and, like you, had all kinds of tuning problems. So I stuck with the extreme-fi 50mm stock one for the truck. So far, so good.

I got my fuel pump in, now I just need to drop the tank and get it installed.

good i glad to see you did not go with a holley. i think this spring iam going back to a stock one. and remember clean and shinny dose not always make it go fast

[dieknow]

How is this thing running? lol!

[g9m3c]

Originally Posted by dieknow

How is this thing running? lol!

For real man, I'm curious!

[ImpalaGuy]

Originally Posted by dieknow

How is this thing running? lol!

Thanks for asking guys. It's running pretty good but the tune isn't done yet. I got the new fuel pump installed: Walbro 190 ltr/hr. Not a lot of fun dropping the tank in the cold but it's done.

I also found out that the stupid xtreme-fi adjustable fuel pressure regulator had my fuel pressure at 30psi! No wonder I was having flooding problems on startup! I didn't know it because I didn't have an adapter to measure the pressure with my gauge (I do now!) and just put the set screw in the middle of the travel.

I continued to backed out the set screw and measuring the fuel pressure, until it fell out. It's down to 17psi which is as low as it can go. That will probably work, but I'm not terribly impressed with the xtreme-fi AFPR.

So right now Brian sends me a new tune or two every day, and I capture datamaster logs and send them back to him. The $200 for his experience was well worth it. I still haven't tried another wide-open-throttle run. We need to get part throttle closer first. I do expect to pull a WOT blast in the next day or so. I'll keep you guys posted.

[Fast305]

Originally Posted by ImpalaGuy

I continued to backed out the set screw and measuring the fuel pressure, until it fell out. It's down to 17psi which is as low as it can go. That will probably work, but I'm not terribly impressed with the xtreme-fi AFPR.

You can use the stock spring in the Xtreme-fi unit as well. Mine was perfectly adjustable from 8-30 PSI with the spring supplied. The stronger silver spring worked from 15-45 PSI.

Originally Posted by ImpalaGuy

So right now Brian sends me a new tune or two every day, and I capture datamaster logs and send them back to him. The $200 for his experience was well worth it. I still haven't tried another wide-open-throttle run. We need to get part throttle closer first. I do expect to pull a WOT blast in the next day or so. I'll keep you guys posted.

LOL, I have been helping Kurt (OldRed95) for free. Nothing real special there. Just make sure you have enough fuel to cover peak demand and pull fuel at part throttle via BLMs.

[Domino68]

Are there any updates yet???

[ImpalaGuy]

Thanks for asking and sorry I've been so quiet. I've been crazy busy at work plus the truck has been frustrating so I haven't had much good news to report.

First here's my story on what comfounded me for the last several weeks: the dang thing would almost never start when cold. Here in Kentucky it was near 0 every morning and didn't get above freezing during the day so this got old REAL fast. Brian at TBIChips and I went through lots of programs trying to richen or lean it or change the timing and nothing had much effect. Checked fuel pressure, timing, injectors, nothing seemed wrong. Hot or warm starts were fine, and once it started it ran pretty good. Well to make a long story short it was the STUPID COIL. I used the same one as I had on the old motor so I never really suspected it, especially since it ran fine once it started. My clue was when I decided to check the timing while cranking the engine. I noticed that the timing light missed a flash sometimes. At the time I didn't think much of it and moved the inductive pickup closer to the distributor. Of course the timing was fine. It wasn't until later I started thinking about the intermittent flash and wondering why I had to move it.

I've always got to keep reminding myself not to ignore data. Too many times it's those little things that you brush aside that end up being the biggest clue to what's wrong.

In this case I think the coil just didn't have quite enough "oomph" when the battery was cold and the cold engine sucked more current to turn over. Once it started and the alternator took over the coil sparked fine. A warm battery/engine and it must have had just enough to spark. I think that the new distributor I put in there may have something to do with it as well. It may take more spark to jump from the pickup. At least that would explain why that old coil never gave me a problem on the old motor. Who knows. Anyway a new MSD Blaster coil fixed that problem real fast.



So that's old news, now for the new news...


Right now the truck runs fine in general driving or WOT but still has two issues:
Hesitation. Pretty bad when I smash over 50% throttle from idle. Sometimes it dies. I've combed the intake and TBI for vacuum leaks and haven't found anything wrong mechanically.
Poor running in open loop. It spits and misses and pops. Once it hits closed loop (3-4 minutes) it clears up almost instantly.

I think both of these are the tune, but I can't complain about Brian at TBI Chips since he's been very responsive. In fact he's sent me SEVENTEEN TUNES so far trying to work these things out. Sometimes even two a day. And the first 6 or 8 was chasing the stupid coil problem above and the fact that the xtreme-fi adjustable fuel pressure regulator won't go below 17psi.

The good news is that I put in a new fuel pump (Walpro 190l/hr) and at WOT it runs GREAT. Yank's Truck Thruster 2600 stall converator stalls around 3000 behind the 383, so the engine really jumps into its power band. I'm anxious to get it to the strip this spring.

So that's the scoop. I'll keep in touch.

[Fast305]

Originally Posted by ImpalaGuy

So that's old news, now for the new news...

Right now the truck runs fine in general driving or WOT but still has two issues:
Hesitation. Pretty bad when I smash over 50% throttle from idle. Sometimes it dies. I've combed the intake and TBI for vacuum leaks and haven't found anything wrong mechanically.
Poor running in open loop. It spits and misses and pops. Once it hits closed loop (3-4 minutes) it clears up almost instantly.

I think both of these are the tune, but I can't complain about Brian at TBI Chips since he's been very responsive. In fact he's sent me SEVENTEEN TUNES so far trying to work these things out. Sometimes even two a day. And the first 6 or 8 was chasing the stupid coil problem above and the fact that the xtreme-fi adjustable fuel pressure regulator won't go below 17psi.

The good news is that I put in a new fuel pump (Walpro 190l/hr) and at WOT it runs GREAT. Yank's Truck Thruster 2600 stall converator stalls around 3000 behind the 383, so the engine really jumps into its power band. I'm anxious to get it to the strip this spring.

So that's the scoop. I'll keep in touch.

Why are you worried about going below 17 psi? Assuming you stll have the stock 61 lb/hr 350 injectors, you should be worried about getting it up around 25 psi and tuning it from there.

The hesitation is lack of tuning in the AE department as well as the increased throttle body size and plenum volume in your intake. The requirements are drastically different from the stock sized TBI and the tiny heated plenum of the stock intake. I bet DE is just as bad with possible surging on deceleration.

Idling poorly in open loop is a sign that the VE tables or the timing is off.