I thought folks would like to see my results, and I'm interested in feedback. This is with my LT1 383:

-LE2 heads
-PAC 1518 springs, replaced the 918's from Lloyd, same setup.
-LE3.2 cam installed at 108 ICL (that's just how it worked out).
-VRE Shortblock
-Compstar forged crank/6" H beams
-Splayed 4-bolt
-Mahle flattops
-12.52:1 SCR
-8.84 DCR using the IVC numbers measured at .004, but I don't know if that's the right cam point to use. DCR is higher using IVC at .006, of course.
-Original stock 84k lifters @ 1/4 turn preload, engine running method.
-58mm Summit TB, modded IAC
-Pacesetter LT's, Flowmaster 80 series, 3", cutout under rear pass seat area.
-Stock W.P.
-M6, 3.42 10-bolt.
-Moroso CAI
-Autolite 104's gapped at .035
-Fuel Pressure 47-48 driving at WOT, 43ish connected at idle.

I went to Vector Motorsports last Thursday for the tune, on a Mustang dyno. This was after about 300 break in miles. We got:

Cutout Open
417 SAE RWHP at 6200 RPM
391 SAE RWTQ at 4700 RPM.

Cutout Closed
405 SAE RWHP at 6200 RPM
377 SAE RWTQ at 4600 RPM.

There are 3 different runs graphed below. The first two are cutout open on the final tune. 3rd is coutout closed. Note the second one (11:49 AM) is a little lower peak. The more concerning thing to me is that for that 2nd run, power fell off much faster after peak, then picked back up a little.
------------Run1 Run2
6200 RPM---417---416
6300 RPM---417---404
6400 RPM---415---376 (Down 39 HP!)
6500 RPM---410---378
6600 RPM---------388
6700 RPM---------381

What do you guys think about that? Video of that run here:


Tuner thinks it is valve float, but it didn't happen on the first run, so I hope we didn't hurt anything. There was some non-magnetic, silvery and golden metal in the oil at the 40 mile change, and still some but less in the oil at the next, 300 mile, change. That was by checking the bottom of the drain pan after letting the oil set for a couple days. Filter only had a few flecks inside at 40 miles, didn't change it at 300. Magnetic drain plug was almost clean at the 2nd change. #3 valvetrain is a bit ticky ever since start-up, and I've lashed 3 times starting at 1/8 and working up to 1/4 preload. Should I worry?

Cutout open 1st run:
[IMG][/IMG]

Cutout open 2nd run:
[IMG][/IMG]

Cutout closed:
[IMG][/IMG]

I'm pretty happy with the numbers. Torque curve is as flat as I have ever seen, and the cam drives great. Surges a bit, but I can drive at 1700 RPM or so in 1st gear, and less in 2nd, as long as I'm on the gas a little. Idles great at 850 RPM with a nice lope, but only after I drilled the TB IAC hole (3/16) and also connected the IAC passage in the TB to the intake. Big improvement! IAC at 20-30 AC off, and about 80 AC on.

I'll post the idle sound later, in a separate thread.

The WOT tune seems ok, although I still have some high/low/split BLM's at less than WOT. More on that later when I can log again - Freescan quit working on me.

With the base tune there was up to 12 degrees knock retard, but it dropped to 1-2 degrees on 97-98 octane mixed with 16 os. of Torco Accelerator in a tank of 93, so I'm sure it was mostly or all real. Total advance after dyno tune is 20 degrees on 93 unleaded. Only knocked 3 degrees as tuned on dyno at WOT around peak torque, but on the streets I get up to 5 degrees or so at part throttle, and sometimes up to 7+ off-idle. Again, got better with Torco added, but still there. Hard to tell precisely since with Freescan not working I'm stuck using an Actron while driving.

I had ignition break up at 4500 RPM when we started, but I wiggled the ICM connector and moved the coil wire away from it, and cured the problem. Looked great after that.

All tuning was at WOT, maybe 8-10 runs total. Can WOT tuning also properly tune for part throttle, especially regarding timing tables and knock? Tuner said A/F was good, gradually ramping up to 12:1 at peak power to be safe. But, he couldn't record the data, realtime only. Wideband was clamped to the cutout, so there was some reversion affecting the readings sometimes, but he said it worked fine that way for tuning.

I'm planning to go to Milan Dragway on Aug 9, if I decide all is OK with the motor. Old street tires and light flywheel, with no practice yet, so I'll warn you now that MPH will be a better indicator for me than ET.

Thanks for reading and pondering my results!

 

Did you check the installed height on your springs when you swapped them out? And you need to figure out why you are getting 5 degrees of knock retard on 93.

 

did I read that right, that you kept your stock 84k mile lifters? Shouldn't the lifters need an upgrade with an LE3 cam?

 

Are you running 1.6 rockers with that LE3.2 cam like your sig says? I have the same cam, and Bret told me it was designed for 1.52s, so thats what I'm running...I'm pretty sure that with 1.6s that cam has too much lift for your springs, what installed height are your springs at?...maybe Bret will chime in with his input on this....

 

I have some of those PAC 1518's coming in the mail . Looks like you would have around 450RWHP on a Dynojet, Great numbers

 

The LE3.2 has more than .650" lift?

For the OP, I think there is still some left in the tuning. You need to get rid of the detonation so you can full out tune the car. I'm running 12:1 SCR, and I can run the car with full timing on pump gas (93) and at 175-180*F. 12:1 is too rich. What was your WOT timing advance? Nice numbers first time out.

 

No, I did not. I kept the same install height that Lloyd had set up for the 918's. I understood the 1518s were direct drop in. Do I need to re-check? I kept the valves in the same places, but not retainers or keepers.

Yes, I did. Per Lloyd/Bret, assuming they were clean and undamaged, that was OK. In hindsight I wish I had replaced them, just to eliminate concern. Next time intake is off I will. Hopefully not soon!

Yes, 1.6 NSA RR ProMagnums as recommended by LE/BRE. I understand they give me .600 at the valves.

Good, I think there is room to improve the tune, too. Maybe I need a better tuner. WOT advance is only 20 degrees. The remaining few degrees of knock could be false...I just realized that with my tune I am getting MORE knock on 98 octane than I did before the tune, even though there is less timing. That doesn't seem right, unless false knock has increased a bit. I guess I should dump in more Torco, to get 104-ish octane, to make real sure the knock goes away entirely, and thus is real. Maybe mechanical noise levels in the motor are increasing, causing false knock to develop the more I drive it. That wouldn't be good. I'll look for exhaust hitting something, I know the system could have moved around a bit.

Thanks all for the feedback so far.

 

No, but I was instructed to set-up my 918s @ 1.75" for that cam, so if I was running 1.6s the lift would be a little too close to coil bind for my personal comfort

Bret told me that this cam was designed for 1.52s and should not be run with 1.6s. I'm no cam expert so I don't know what the primary reason for this is, I just figured that I'd share that bit of info...

 

There must be 2 versions of the LE3.2 cam then. Mine said right on the box "LE3.2 1.52" and like I said Bret instructed me to use 1.52s.

The lift of my cam with 1.5s is .586, and with my 1.52s ends up being .593, and 1.6s would put it at .624....so something is different here....

 

20* @ WOT?? Are you running a coil pack per cylinder type ignition system?

He's running the PAC 1518's, which don't coil bind until 1.080". The 918's are equivalent to the PAC 1218's, which coil bind at 1.140". His springs are fine.

Also, the stock lifters are fine.

 

Ahhh I see I was thinking the coil bind would be the same as mine


On a side note, now I'm really curious as to why his cam is different than mine

 

Did you have a wideband hooked up?

What are your springs set up at? I'd heard a few stories of which the springs were set-up all over the place. If you're running a .600" lift cam you can install those at 1.750 to give you some more seat pressure, but I think Lloyd sets them up there anyway. I would double check.

You should try throwing some race gas in it and see if your power hole goes away. Might be the computer pulling some timing.

You can try giving the lifters another 1/4 turn of preload to see if that quiets them up. Your lifters seems to be the weak point in your valvetrain. It wouldn't hurt to replace them.

 

I would check to be sure, my springs were all over the place, I found one at 1.8" and a few at 1.78" ect.

 

How does that happen?

 

383s and 350s may require different valve timing even when using the same heads. The "3.2" really is a family of grinds with different ones specific to the whole combination. One size definitely does not fit all applications.

I suppose I could be more specific, but then I'd have to shoot you...or get shot by Bret. I don't go by my nickname, but if I did, I'd be Jack Bauer. Beware!


Jon