One more thing the later style fuel pressure regulator cover is not as easy to unplug. Its threaded part is just crimped lightly into the outer can with a blob of metal dropped over the screw. I followed the instruction for the early style not thinking there was any difference and the crimp came loose causing the whole assembly to just rotate and wobble. I have an aftermarket Jet cover coming tomorrow.
VAFPR_2_.jpg
After all the hassles, I fired it up today. It's still not completely together, but I wanted to make sure the lifters pumped up and the adjustments where correct before buttoning up the rest. It idles fine, even with the stock chip. Fuel pressure, slight min air rate adjustment were the only changes so far. I didn't mess with any other changes yet as I knew it would run well enough to check the lifters. The exhaust sounds good too.
Last edited by donf; 12-17-2018 at 06:46 AM. Reason: Spelling
On the stock chip that is about all I suspect it will do. Startup and idle well. As soon as you crack the throttle I bet it runs like crap on the stock chip. With Vortec heads I generally have to add ALOT of timing and atleast 50% AE.Originally Posted by donf
On the stock chip that is about all I suspect it will do. Startup and idle well. As soon as you crack the throttle I bet it runs like crap on the stock chip. With Vortec heads I generally have to add ALOT of timing and atleast 50% AE. For being such a small cam the 395' Marine cam really does sound good. Looking forward to seeing how much of a difference it makes. I am guessing you will put down around 240 hp to the tires if it is tuned well.
With the holidays and a new job, not much time for the van, but i did get it back together today and backed it out to run for a few minutes. It idles fine, even on the stock chip, but like I was told once the throttle is opened it starts going lean fast even with 20psi. I am not driving it this way, I have not even driven out of the driveway yet, but figured I would post an update. I was concerned a little about the ramjet cam as a few people said I may have trouble getting it to idle with the 109 lc. At least with the 1995 computer it idles fine even with the stock timing and fuel. I have done some very conservative changes to the chip now, but the fuel tables need to be dialed in better before loading it too much or driving. I ordered a mr gasket 180 high flow thermostat (Robert Shaw Copy) thinking it may be better for towing. I think that will have to be changed out before the van leaves the driveway. Too much trouble keeping it up the temperature in winter weather. As soon as it starts to open the temp drops by 20 degrees fast, so the temp gauge pogos back and forth every 10 minutes or so. It had a super-stat in it before, and it did fine in all weather. Live and learn.
I always have had good luck with the GM 170*F marine thermostats. Will see if I can find the part number. Should still be a good one.
Will also send you an Excel file with the VE table and Spark advance tables out of my Vortec with the Ramjet cam. Probably a better starting point than the TBI stuff.
Last edited by Fast355; 01-03-2019 at 12:49 AM.
GM 170*F thermostat without coolant bypass port blocker.
GM 10220957 or AC Delco 131-84
https://www.summitracing.com/parts/ado-131-84
FWIW, for anyone running a Vortec engine. The GM 170*F thermostat for it.
Has the coolant bypass blocker built on the bottom.
GM 19114467 OR AC Delco 12T19CJ
https://www.summitracing.com/parts/a...j/applications
Last edited by Fast355; 01-03-2019 at 12:41 AM.
Thanks for the advice. I just left the 180 mr gasket in there. Most all local parts houses went to Motorad for their supplier. Even Stant is a special order. I did not use the shim head gaskets after all. I just went with a .026 composite as the block had a tiny bit of pitting around the water ports. I know that may have hurt the end result slightly, but after 2 months of messing with crappy import jegs heads, I did not want to do it again for a long time.
I burned a dyno only chip to lock the converter very early and keep it in third and I put it on the dyno for about 15 minutes yesterday. No extended power runs, mostly just moving the throttle as slowly as possible while cranking up the resistance to see what block learn does. In the lower rpm ranges and the converter locked, I had to crank the eddy brake up a lot to hit some of the cells to lug the engine down enough to hit some of the lower rpm block learn cells at low vacuum, so I am hoping that means a little improvement in trailer towing torque.
On the dyno chip I did adjust the injector flow rate to account for the increase in fuel pressure, but kept the stock VE tables. The $20 generic fuel pressure spring I got off ebay, will not drop the pressure below 19.5psi even with the adjustable regulator backed all the way off making it rich at idle with the stock fuel table. FYI The ebay spring looks and feels real similar to a pack of springs a friend got from mcmaster carr. https://www.mcmaster.com/9657k521 Some of the cells on the fringes are not accurate. I hit those on decel after wot. Most of the the cells though were hit several times with no sudden throttle movements. I had a mostly stock vortec timing map in there, looking for any knock when lugged, it was fine so I can bump that up a little as suggested too. I did jump on it a few times and the wideband AF ratio on the dyno would lean out just for a fraction of a second (I will fix that) and go straight to 12.5 and hold that with no adjustment to the factory PE time tables. Next I need to read up on out how to do emulation to dial in the fuel and timing tables easier.
Last edited by donf; 01-07-2019 at 02:23 AM.
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