I am about to fire, for the first time, my transplanted and completly rebuilt 1990 L98 5.7 TPI. Any precautions/suggestions??

I know it is a very general question but any advise would be apprecitated.

Alittle background...
Lunati Cam .510 lift .213 duration (single pattern)
Ceramic Coated Tri-Y headers
700R4
Pocket ported 113 heads
Balanced, line honed
Decked (w/plate)
Approximately 10 to 1
Stock HEI
Comp Ultra Pro Mag rockers 1.6 and 1.52
No EGR, no VATS, no emmisions required
True roller chain w/torrington bearing

Thanks in advance...

 

typical new start manually prime the oil pump look for oil pressure
check fuel pressure...
make sure you line up the rotor @ the exhaust valve of number 3 CYL
easier start
unplug your adv time... short A&B on your ALDL
warm up check for leaks set static to 6*

your going to need a tune... that's for sure

 

Thanks and I guess I forgot an important item...I got a custom PROM from Howell Engineering in Michigan. It was tuned to my specs.

Why is 6* so important for static timing. Can't I set it to 8*?

 

did he set your timing to 8* on your custom

 

What you are saying is I have to set the base timing to whatever was programmed into the PROM so I should contact them to get the info. right? Thank you for bringing this up.

 

UPDATE...I contacted Howell Engineering (the people who programmed the PROM) and he said since I'm running the #113 Aluminum heads I can set my base timing from 8 to 10 degrees. I understand this to mean the base timing in the PROM must have some wiggle room.

Any thoughts?

 

Ok I need some HELP please!!!

Fired up the motor for the first time and I can't get it to idle at less than 950. Idle screw is backed out away from the linkage and the butterflys are where they are supposed to be.

Prior to the initial start I set the TPS to .50, knowing I would be setting it again after I got things settled down, and I set the initial timing at 8*, with the spout disconnected, then reconnected. The motor sounds AWESOME but I need to get it on the road and get the rings seated so any help would be greatly appreciated. I did the IAC procedure (jumper A&B and disconnect the IAC etc. and heard the IAC motor move. Also check engine light is on.

 

OK I feel like I'm talking to myself...anyone? I do have an update though.

I got the base idle where it needs to be by re-jumping the ALDL and unplugging the IAC. Must have not completly jumped it correcdtly the first time. I also got the TPS set to .54. Now (as I previously said) the SES light stays on so I ran down the code to a 43 (electronic spark control circuit). It this either the knock sensor or the module in the distributor? The knock sensor is new!

 

Did your factory prom get these codes???
put your factory prom back in to see if you get the same ESCC code 43
check your connection on the KS....
you cant read the H.E. custom... so have them send you a printout of what they actually changed... did they balance out your timing from... 600 - 1000 rpm's ????
factory injectors??? you have a lack of info..... to really respond
any other mods....??? did you verify vacuum leaks??? have you even ran your mods on the factory prom
to make sure your base is working properly... idle should be fine.......

 

I guess a little more back ground is in order...
Never had a factory PROM
7730 computer came from a donor vehicle (checked OK)
24# bosch/denso injectors
no vacuum leaks (that I can find/hear)
painless wiring harness
this motor has been transplanted into 1985 GMC 4WD pickup
replaced EVERYTHING (I think)
Painless sent me a diagnostic flow chart to check the Knock so I'll do that over the weekend
Bored .020 over

Thank you for your help...

 

UPDATE---Per the diagnostic chart I checked resistance from the Knock sensor to the block and got 100. It should be between 3200 and 4500. BAD Knock Sensor!! Local auto parts place exchanged it and now no check engine light

I feel the idle is too high when warm...what should these TPI motors idle at when warmed up? (auto tranny)

 

do you know if H.E. modified the cold idle settings
factory cold idle will bounce around from 1800ish if i recall correct
once it reaches closed loop you should idle @ 850

P.S. now this is where GM should have installed A TPI motor... in a truck
a perfect match for low end torque... nice choice... I know you will be happy with that upgrade!!!
not sure the 700Weak4 will be so happy

 

I can't wait until I get all the bugs worked out...It should be a very nice combination!

H.E. seems to have gone cold turkey on responding to my e-mails but I'll keep checking with them. That said I don't know if they modified the cold idle settings. The motor runs faster on initial start then settles down, which is the way it is supposed to be, I think.

Thanks for the continued help