Smallblockguy

Got to the track tonight! I was able to configure the autotune afr table to use the gas scale equivilents while burning methanol and it tunes perfectly. The transition from gas to methanol is SEAMLESS!!! so happy with it. I am using 1600 rpm as the only parameter to trigger the switch.

I stopped at the scale on the way to the track, car weighed 3578 lbs with me in it. Went 1.99 60 ft, 7.97 @ 91.06mph 12.15 @ 116.34 leaving on 40* total timing ramping down to 24* @ 5.5 psi and a 4.0 afr (9.1 on the gas scale) This thing is a blast. Used less than 1/2 gallon of methanol over 5 passes! That's cheap race gas!

Forcefed86

iTrader: (4)

Congrats thats awesome! Now quit dorkin around and crank it to 25lbs!

Smallblockguy

I know I know, haha

Smallblockguy

Here's my current ve table, 125.8 is the relevant fuel load @ 5.5 psi. The ve numbers seem high??? I have the required fuel amount set up for gasoline, havent figured out how to set it up for the methanol amount yet without causing the gasoline injectors to go way rich... if it aint broke don fix it??? seems to work this way.

Smallblockguy

Here's my next timing table to try. The last one was very similar except the ramp down from 40* started at 2000 rpm instead of 3000 rpm. full boost between 4500-5000 rpm

Forcefed86

iTrader: (4)

That timing table looks pretty good. I’m sure you’ll end up with something similar to that in the end. But I wouldn’t just set the timing that high and pour the boost to it. Personally I think it’s less dangerous to tune the other way around. I’m much less afraid of boost than I am of timing. IMO you should get your AFR on the rich side with overly “safe” amount of ignition lead. Then dial in your peak boost. The last step would be to sneak up on timing slowly. Your sort of a special case though where you’ll end up with high timing and high boost.

IF you want to trap 135 or so at 3400lbs you’ll need 670ish hp. I’d guess around 18-20lbs? I’d try that first with 12* timing or so. Then bump timing up a degree at a time until you stop making big gains. (like denmah was saying) You may still end up with 25*… But I’d get there in baby steps.

Can’t wait to see what this thing does with some decent boost!

Smallblockguy

Yeah, I agree. I plan to reset the parameters everytime I go up a boost level.

Gonna try to get this pig to leave first though.

I want to try and configure the step retard to create an anti-lag type backfire while at the starting line on the two step. Build a few p.s.i. And leave in second gear (1.62 ratio) is the fantasy.

Smallblockguy

Systems are working great! She's really fun at 10 psi. Pulls right to 7000 rpm. No track numbers yet. I Changed a wastegate spring out and ended up at 23 psi! Useless. Does not respond to tuning changes, lays over goes uncontrollably lean, I believe I am into valve float, hard. Starts going lean around 5800 and is useless after 6500 rpm.

Gonna pull the spring back out and see if I can find a 14 psi combination.

Forcefed86

iTrader: (4)

Can you put the lighter spring back in and then run an adjustable regulator to the top port of the WG? I use this method and it works great. Regulator is mounted on the dash. With the bottom port hooked up I can dial in as low as 9 and as high at 19 form the driver seat. I have a ball valve on the bottom port for track visits. With this closed I make 20-26+ depending on regulator position in the car. $9 boost controller that works great!



That lean thing sounds nutty with your fuel system. From what I’ve read the stock cam peaks out around 5400 on a 4.8. If you keep the rpms down you should be able to run alot more boost without valve float. I’m sure it would go much quicker at 20lbs and 5800rpm than 10lbs and 7000rpm. May give it a shot to see if it gets rid of your lean situation. Always wanted to see what the $125 zr1 cam would do a 7k in a 4.8.(hint* hint*) The ZR1 made nasty power form 5700 and above in my 5.3. I was too nervous to take it much over 6500 though. The $150 PAC1218’s are a single drop in beehive style spring and with the zr1 were good to 6500rpm at 25lbs on my S475 FWIW.

Smallblockguy

Sweet boost control setup!!! I can do that!

Smallblockguy

I had one setting wrong in the required fuel calculator, I set the afr to 4.0, moved it to 14.7 and it brought the required ve number WAY down, lots of room to grow now

Smallblockguy

Got to the track on 10 psi this weekend. 2.06 in 60ft, 7.88 @ 92.25, 11.99 @ 119.49. SO fun and fast on the highway, such a pig of the line at the track. Needs a new trans, converter and gear combo badly. Just ordered some PAC 1218's, should be a good back half number with those.

Smallblockguy

I have realized that the low compression 4.8 does not benefit from methanol until its into boost. Current trigger is 1600 rpm, gonna move that to 4600. Current set up won't hold above 2200 rpm at the line.