New ole guy

[Jobo]

Hello everyone, im trying to gain some knowledge about how to get my 87 g20 van on the road again after a lt1 cam swap. Some posts on other sites say it'll run on a stock tune but so far no luck for me. If i would have known there would b a domino effect i would have thrown a carb on it but im so close now that i have to see this through. I kno nothing about computers wich is why it took me so long to post my first thread. Thankx for having me & i hope your forum can help me getting my buggy going again.

[dave w]

I understand the domino effect of swapping parts on an EFI engine. I would agree a stock chip will get the engine running, likely not very well but running.

Is the engine starting and running?

If the engine is starting and running, please post a TunerPro RT data log; see attached screen shots from a TunerPro RT data log. Data logs are essential for figuring out a "no luck for me" comment.

A doctor uses a EKG strip to monitor a heartbeat. EFI requires data logs, it's how tuning is done.:thumbsup:

dave w

[Jobo]

Thankx for the reply, how do i get a data log? Excuse me if this is posted twice, still tryin to navigate this site.

[dave w]

Thankx for the reply, how do i get a data log? Try this link https://ls1tech.com/forums/lt1-lt4-modifications/1298009-tunerpro-rt-v5-tutorial.html

It's for a different engine, but setting up TunerPro RT is still the same.

dave w

[steveo]

Some posts on other sites say it'll run on a stock tune but so far no luck for me.

i've never seen such a mild cam swap throw a tune out so bad that it wont run and drive around the block. you're missing something, it's NOT the tune

[Jobo]

Thanks for the help Dave, ill save ur thread in case i find someone who knows how to turn a computer on. Ur comment
That its not the tune will urdge me to dig into it again. The only thing im not shure of is the tps. It checks out good but think the volt setting needs tweeked. It starts right up, idles good but dies when u give it gas. I tossed a flat tappet in before this (420-443 110lsa) it ran&drove but died if i wasnt gentle on the gas. Ill try the tps again today & c what the result will be.

[dave w]

"find someone who knows how to turn a computer on."This is an all to often comment about EFI, it's unfortunate but true. Tools are tools! I would never attempt to use a sledge hammer when the correct tool is a torque wrench. Computers and EFI system are equally challenging when attempting to use a sledge hammer when a torque wrench is required. The correct tools for EFI are an ALDL Cable http://www.aldlcable.com/products/aldlobd1u.asp and a TunerPro RT Software (a suggested $39 donation) a very modest price for the "Ultimate EFI Tool". TunerPro RT is more than just a data logging tool, it's also the "BEST EVER" TBI Scan Tool!

Sometimes the following statements are true:

The more you know about EFI, the less you pay for EFI.

The more you know about EFI, the better you can GOOOOOOO with EFI.

dave w

[Jobo]

Thank u again Dave for informing me of the cable. Im in process of locating someone who can handle doing this. Ive heard of someone u send your prom to & they reprogram it according to what mods u have. Kno anything bout that?

[Fast355]

Thanks for the help Dave, ill save ur thread in case i find someone who knows how to turn a computer on. Ur comment
That its not the tune will urdge me to dig into it again. The only thing im not shure of is the tps. It checks out good but think the volt setting needs tweeked. It starts right up, idles good but dies when u give it gas. I tossed a flat tappet in before this (420-443 110lsa) it ran&drove but died if i wasnt gentle on the gas. Ill try the tps again today & c what the result will be.

Sounds like you need to check the basics to me.

I ran a 204/214 @ .050 cam in a 305 TBI in a G20 van on the stock chip. Ran a 204/214 @ .050 cam in a 350 with older 601' 305 carb heads. Also ran a factory LT4 cam in a TBI 350. All 3 were run on the stock ECM chip and injectors for that size of engine. All 3 ran very well and were absolutely driveable with good power gains over factory.

You need to start with the basics. Fuel pressure, Timing advance, firing order. I have seen the fuel pressure regulator springs break as well as the fuel pump insulator (spongey rubber hose in the tank between the pump and sending unit) fail. Both will result in very low fuel pressure and exhibit symptoms close to what you are describing. Fuel pressure should be 11-14 psi for the engine to run well with 13-14 prefered. Your base timing should also be checked with the EST bypass connector disconnected. Factory timing spec is TDC or Zero at idle speed. With a mild cam you will want to bring that up to 4-8* in most cases and possibly as much as 10* depending on how it runs. When you shut the engine off, remove a battery cable for 30 seconds, plug the EST connector back in and restart the engine the timing should jump up 16-20* higher than the base timing at idle.

[stew86MCSS396]

I just want to clarify that we are talking gen II LT1 and not the ole school solid lifter LT1 but then again who would use that cam ina heavy vehicle, no?

[dave w]

Thank u again Dave for informing me of the cable. Im in process of locating someone who can handle doing this. Ive heard of someone u send your prom to & they reprogram it according to what mods u have. Kno anything bout that? There are members here that I've helped with a "Starter" Chip. There are some changes required to a Chip if the engine has been modified. I think the "Myth" has be busted that chip can be programmed that is plug-n-play ready "Tuned" with only the information about the modifications. The reality is, knowing the modifications will get a chip programmed that is closer to a "Tuned" chip than a stock chip. Is closer in the "Ball Park"? Is closer down on the playing field of the "Ball Park" or maybe closer like in the back of the parking lot of the "Ball Park"?

The best way to tune a chip is with data logs.

dave w

[Jobo]

Hi guys, once again i thank u for ur imput. To fast, ur news is encouraging, lil info on this motor, 1987 350 i converted to roller with a 96 camaro cam. 447-205, 459-207, lsa. 117. Kemso 340lph pump, stiffer reg spring at 15lb. & is adjustable. Corrected iac. passage, spacer & velocity stack air cleaner. Im at 8° right now. To Dave, i fully agree with u & is somthing i definitely want to do. Goin out now to check bacis again. Ill let u kno if i get anywhere.

[Jobo]

I did find a leaky o-ring on an injector, maybe a loose lifter, i got thoes used, ill do a running adjustment this time & c if that helps. I also want to swap out the ign. Module again with known good ones to c if that makes a difference. Ill post after im done.

[Fast355]

I did find a leaky o-ring on an injector, maybe a loose lifter, i got thoes used, ill do a running adjustment this time & c if that helps. I also want to swap out the ign. Module again with known good ones to c if that makes a difference. Ill post after im done.

Unless you know the full history of the van check your injectors for part numbers and make sure you actually have 350 injectors and not something else. Alot of guys run out into the junkyard grab a pair and do not know they were offered in about 10 different flow rates.

[Jobo]

Thankx for imput fast. Im (c) owner & kno motor was all stock (till i got my mitts on it.) I have 4 spares & r from 350s. All have a good conical spray pattern to me. It may take some time between post as my time allows me to work on project. I value any & all imput!

[Jobo]

Sorry for delayed post, been buzy with docs&hosp. but i did the running valve adjustment & gave it a blip after i was done & it responded.

Sorry for delayed post, been dealin with docs&hosp. but got running valve adjustment done & gave throttle a blip before i shut it off & it responded. Today i hope to remount the real valve cover, replug everything & c how it runs. I think the used roller lifters had a home at 1 turn & i had them set at 1/2 like the hp. guys suggest. Ill let results known soon.

[Jobo]

I just received a new set of genuine GM lifters yesterday & i will post the results after they are installed. Thanks for your interest.

[steveo]

setting up hydraulic lifters can definitely be bitchy the first time. too loose shouldn't affect how the engine runs, but if they're way too loose they'll be noisy or smash the clip out. if your engine wouldn't rev up, you probably had one too tight, maybe because it was collapsed and you couldn't tell you were adding too much preload.

one thing to consider is that you should set them up right now with the intake manifold off, you can find cam base circle and zero lash so easily when you're staring at the lifters themselves.

you may even consider making yourself a round feeler gauge with a bent tip that you can put between the clip and the lifter to actually measure your lash, it should make things really obvious. i think 0.040" would be a good starting point for most sbc lifters but you might want to look that up.

[Jobo]

Thankx for the tip Steveo. Never heard of adjusting lifters that way! Nvr too old to learn. Makes sense to me. The running adjustment i did, didnt go as usual as some clacking was present when done & afterwards died on test ride up a steep hill.

[1project2many]

i think 0.040" would be a good starting point for most sbc lifters but you might want to look that up.

Hydraulic lifters are intended to be preloaded. .001" is a "loose" lifter preload setup for racing. Typically they'd be set around .015 to .020 based on commonly found internet instructions. (1/2 turn after 0 lash on 3/8 X 24 TPI results in 1/2 of 1/24" or 1/48" movement, equal to .0208"). Most lifter manufacturers actually recommend .020" -.040".

[Jobo]

Thankx for info One Project. Cant really do anything outside between 8.5" of sno the first day of spring & now 5 days of rain. Think ill go for .020 preload when i get a break frm the weather. Thankx for everyones imput.