odddoylerules

ok my stuff is all installed on my fiesta as i continue that nightmare, so I cant really help my friend out much.

He installed the same rv cam I have in my RS 350 swap in his truck and added vortec heads, but its not running right. He's fiddled with timing, and hes about to fiddle with fuel pressure, but I was like hold on, lemme see if we can figure something else out.

So i have my moates gear, but my wb and egt sensor and datalogging stuff are in use. do you guys have some basic information about how timing and fuel are effected by the new heads? I was reading about some ppl with zz4 cams and tpi, but that stuff is not entirely applicable.

Anyone know someone with a vortec head truck that has tinkered w tuning? Just some advice to get us to a good starting point would be appreciated, or if someone has a bin, all the better. In the meantime, im gonna continue searching

odddoylerules

how do u delete a thread i found answers to what i was wondering.... lt1 timing curve here we come!

Ronny

iTrader: (1)

You need to change/verify the BPC and do some datalogs to get fueling correct.

Dont think LT1 SA tables are correct. May be too aggressive(vortec=less timing), also truck heavy which means less timing.

See Fast355 for his Truck Vortec threads.

woody80z28

iTrader: (2)

I used both the iron-head LT1/auto B-body table as well as the LT1/T56 F-body table and got better results with the F-body table, but both were far better than the stock LO5 TBI table in my truck. If my truck was auto the B-body table might be a better match.

The stock OBD2 Vortec timing table is very conservative. I lost a ton of power when I tried it out. With the F-body table I'm sure I'm closer to detonation, but haven't had any issues yet, and I'm 9.7:1 on 87. In the summer hauling a trailer might be a different story and need some 93 splashed in, but I'd take that any day of the week over the power loss I had with the stock Vortec table.

Ronny

iTrader: (1)

GM vortec tables may be emishions conscious .

odddoylerules

he has steep rears and an s10 converter so i dunno if the weight will matter much

Fast355

iTrader: (2)

I had 3.08s and a S10 converter pulling around 5,500 lbs of boxy old school conversion van. B-car LT1 timing map is conservative on the Vortec heads and the F-car LT1 map a much closer match. My 8.9:1 TPI 350 Vortec loved 34* of timing @ 3,200 that the LT1 F/Y-car map delivers.

odddoylerules

sweet

odddoylerules

is there a stock bin for a vortec truck around? a screenshot of a working vortec fuel table or a stock vortec bin would be a real time saver at the moment. LT1 curves arent really making a difference in drivability, fuel is the bitch and my wideband is tied up elsewhere

odddoylerules

research indicates vortec head design was used in off road applications as early as 93. Wouldnt that be still using MAP? I also found a 8546 ecu for a 97 van that says it uses MAP based tables... anyone tried these on a TBI app? It's the exact same motor as my bud bought, so it sounds promising.