Alchy tuning question ?

[BLACKBADGER]

Is anybody running 91 pump-gas with alchy? And if so what kind of boost are you running safely? As we don't have 93 pump gas here. Now on another section someone mentioned an Alchy chip, that they would back off the fuel via chip programing. Now if you are running pump gas with low octane why would you back of fuel via chip vs fpr(1-2lb back off). If alchy is just an octane enhancer it doesn't make sense to back off the fuel with pump gas. Is the reason for backing off fuel because of the decrease in air charge temprature?(just wondering if I can run safely with 91/alchy with 20lbs boost) Right now I'm running 20lbs with a 1:4 ratio of 116/91, which comes out to approx 96 octane on the street. The backing off of fuel while using pump gas doesn't make sense. There's a guy with a 70 monte with a 500 caddy(runs high10's-low 11's) . That runs 91 pump gas a 300hp squirt of Nos and uses a homemade alchy system that turns on right when the laughing gas comes on, to compensate, and I understand his usage and application of using both. Could someone explain the need for a chip burned for alchy application if your only going to run pump gas? I thought it replaced the use of high octane leaded race gas. The ratio and volume of alchy to gas used is small in comparison to the ratio that's needed with gas(1 gal 116:'4 gal 91) . It's not like your running a high volume of alchy per run(as compared to the gas volume and mix that I have to make to run 20lbs boost right now. ) I was planning to get a system this fall, was going to hook her up to come on at 14-16 lbs(i can run 14-15 lbs on 91 by itself) have the alchy come on to reach that magic octane/cold air charge level so that I can reach those higher boost levels and tweak her as I have with the race gas blend, adjusting fpr and making runs to check O2's and KR. I'm a novice but thought I'd ask a stupid question anyway. Thanks in advance!

 

[Mr URL]

Yep! I'm using 91 octane and alchy injection. GN run's 11.80's @ 115 setup that way with 24 psi boost, 5 psi launch. SMC alchy kit with 2 nozzles running denatured alchy. Going to try 50/50 mix next.

My chip does not remove any fuel WOT. What it does do is have low timing (17 degrees) to work well with 91 octane pump gas (keeps alchy turn on point high during spoolup) then goes up with the timing to 22 degrees at 4,000 rpm and above with LV8 100% (alchy is spraying).

Still more left in it with tuning. Shooting for 11.50's in street trim on 91 octane.

 

[BLACKBADGER]

Mr URL

Right now I'm using a high timing chip i.e ATR Pit-Bull and I believe it's 26 degrees on top at WOT. I understand decreasing timing for NOS and the reasoning behind that kind of thinking(i.e. Lower timing). I like the higher timing chips if the octane is there. there's just so much better throttle response, and much better spool up. The lower timing chips run like a pregnant dog here at altitude. Some guys like them, my car doesn't. I'd rather have the high timing on the bottom and pull some out at Wot at the higher boost level. So what you are saying is that it's not fuel tables at WOT that are modified but timing variables for alchy? I guess I'll just have to experiment when I get a system this fall. Here at altitude there's not as much air(lower partial pressure the higher the altitude) to move as there is at sea level( my novice hypothesis), so the only way to get the air that's available is to move it faster, and the only way to move it faster is higher timing am I off in thinking this way?. Thanks