1fastmofo

iTrader: (3)

Ok truck in a 98 silverado vortech w a 383 stroker, edelbrock etec 200 alum head, eagle forged rot ***, h beam rods, fully roller.etc... 3 inch exhaust headers. My problem is that I am trying to run the stock cpi (central port injection) due to the fact that I dont know whats available for that style head. I have had the computer burned at fast and it still runs horrible. Rich at idle and then falls on its face when i hit it. What I would like to know is if anyone knows of a intake that would allow me to switch to a mpi setup. The vortec uses all vertical tappets for the intake bolts.... What does the Ls1,ls2,ls6, etc use. I have found that sdpc sells an intake to use tuneport but I have heard that tpi stops making power around 4800 or so. One of the biggest issues for this truck is the fact that they are not modded. I have used a holley intank pump from a lt1 so that I could use additional psi if needed., I have tried inline boosters.

To top all of that off the truck was built to run the whipple supercharger (which I have) but the engine will not recognize the boost. (whipple says its from the increased flow) Im not so much concerned with that $3500 loss but I dont want to have to change the heads and all that I would just like to know who knows what i can do. This is a fully built show vechile but I would like to be able to get in it and go and not worry rather im running to lean or rich.

firefighter

Look at the Holley Stealth Ram. You won't be able to run the Whip but you can get a complete system to run on the Vortec Heads with a stand alone ecm. I basically built a similar motor for a '65 C-10 should make over 500 at the fly. I should have the truck done in the next couple of months. Btw the system was about $2500 complete, if I remember correctly.

hog

You need to get a GM/Mercrusier Marine Intake, I am using 1 with 24 lb/hr injectors, teh stock truck intake is horrible and uses only 19 pph injectors which are only good for 400 hp, you are running out of injector for sure on a cam/head 383.

http://www.sfatek.com/images/efi.jpg
All the info is here, http://www.pacificp.com/forum/viewtopic.php?t=317

You can use your stock PCM to run any high ipedance injector you want.

James of this site is running a MArine intake on his ETEC 200 headed 383 with a Whipple blower.


If you are interested in marine install kit, they are around $750 and will pretty much drop in. I did my complete install including tuning for $975.

You can also use a Ramjet 350 intake.

peace
Hog

1fastmofo

iTrader: (3)

you said i think in another forum that you were almost one of the investors, are these guys gonna be selling these as kits? I was about to go with amagna charger setup based off of a new style chevy that they have come up w but i wasnt too happy w the price 6gs

you said that James is running a 383 w a whipple what kinda boost is he able to make? I called whipple and they told methat i had to spin my blower at 16k rpms to get 6lbs, and that it would not hold over 14.5k for a short period of time. I built my motor thinkin i could run a max of 10 lbs. which i am now finding is a feat in itself.

I like the deal of the marine intake but the tapping and whatnot of the intake kinda worries me. I am more of a body/suspension guy.

I have fought this setup from the get go that i decided to go 383. I have tried the edelbrock stand alone system that they offer for trucks designed with carbs running vortec heads. not a ba system but injectors are magnetti merelli pico injectors and they only had 2 sizes 29lb/hr and 46lb/hr i believe. And the little computer that it comes with forget it edelbrock himself woulda been scratchin his head.

I dunno but im looking for something cause i hate not being able to drive my truck worrying what kinda damage i may be during due to the fuel/air mixture.

thanks so far guys keep it coming

hog a little more on this setup of yours as far as how it comes.....
thanks

97sicksled

Hey 1fastmofo if your looking to buy a marine intake i got one that i am willing to sell to you 700 shipped to your door.

James B.

iTrader: (1)

This thread needs a better title, I almost missed it!

There have been two entirely different directions your motor can take discussed here, so I'll start with getting your current setup to run right.

The Generation of PCM we have in these trucks struggles with cams that reduce vacuum at idle. It affects everything in the low RPM range, especially throttle response and returning to a stable idle from a throttle blip.

With logging software of some sort you need to find out what the minimum and maximum kPa your trucks idles at. To find the maximum, put the A/C on high, turn on the headlights to high-bean and turn on any other electrical load you can think of then cold-start the vehicle and put into drive logging from that moment. Round the Maximum kPa you see up to the nearest increment of 5. To find the minimum kPa for idle, turn off all electrical loads and A/C and leave in park. Let the engine warm up and then log MAP. The round the minimum kPa you see down to the nearest increment of 5.

The Max kPa value need to be put into the table (BLM MAP Boundaries) for "mid"
The Minimum kPa value needs to go into the table (BLM MAP Baoundaries) for "low"

This is the first thing you need to do to fix the trottle tip-in problem. It will isolate the Trim values for idle into a cell not shared by the conditions encountered just off idle. Right now it's rich at idle but lean off idle causing a stumble. If those two points of MAP vs/ RPM share the same BLM cell you will have some conditions trying to lower Trim and some trying to increase it. They fight and make it impossible to be right.

You can run the 383 with the huge heads and a cam from the stock injectors with the stock PCM, it just need to be tuned right. I'm telling you right now, tuning these PCM is an absolute BITCH around idle, but it is possible with enough patience.

As for the Whipple, Yes, I do have a 1.6L Whipple on a 383 with E-Tec 200 heads, dual 3" exhaust and longtubes, cam, and the Marine Manifold with a 2Bar MAP and 36# (41 @ 4Bar fuel pressure) injectors and no Whippletronics. I have a 2.5" pulley on the Whipple and shift at 5600RPM. I am spinning this supercharger to 17,000RPM which is FAR past its readline. I only get 6psi of boost. On the 350 with the same setup I got up to 9. It desperately needs a larger displacement compressor but I have not decided which direction I want to go with that. I'd really like to see a 2.3 or even a 3.3L unit sitting top dead center on the engine with an intercooled manifold below it... Maybe some day when I grow up.

We can talk about tuning the Boosted setup with a 2Bar MAP sensor, but that is another thread. How's it run? Here's a teaser:
http://bertok.us/pics/383WOT.mpg

hog

More marine intake manifold in fo here.
http://www.pacificp.com/forum/viewto...?t=317&start=0

If you have any questions. fire away.

peace
Hog

litreddevil

iTrader: (4)

i didn't rear the whole post but i know eldborck makes a good mpi with 8 injectors and a throttle body looking deal on top and it also comes with the stuff to tune it real nice

1fastmofo

iTrader: (3)

already tried it thanks cory

1fastmofo

iTrader: (3)

no one else building 88-98's