im spraying my 90 350tpi with a 5151kit...

its a 100 or 150 shot and was wondering if i need to adjust the timing when i do so.....

also what kind of gains should i see in the 1/8th

car is stock with headers and runs 8.80 in 1/8th now

just wondering

 

they say 2 deg for every 50hp. the timing will likely retard itself. this is a wet kit correct? i hope the engine is up to the task. 8.8 is pretty good, what mph?

 

whats your timeslip like now? 60 foot 330, and 1/8 trap speed?

100 shot i'd start with around 4-6 degrees pulled and keep air fuel ratio in the mid 11's if you can. THen add timing back in slowly to see if it can tolerate just 2-3 degrees pulled.

Same with the 150, pull 6-8 and add in timing to see if it handles it. I"d advise on a scanner and a wideband to monitor all this to see whats going on.
Gap the plugs tighter and maybe run a step colder on the heat range.

Should really pick up tho with a 150 shot. My 383 ran 6.76 at 102 in the 1/8 with a 150 shot. Was running in the 7.3's at 93 n/a.

You probably willl pick up more going from an 8.80 to around a 8.0-8.2 or so with a good 7-8mph gain on a 150 kick. Just a guess

 

2*/50 is the standard deal.

FWIW, you loose _much_ less power retarding timing on spray than you do NA so if in doubt run it on the safe side, because unlike NA, where a little detonation usually doesn't hurt much, with decent sized N2O hits a little detonation could mean carrying the engine home in a bucket.

 

i have the same kit on my 88 tpi 350. with a stock converter, 3.73 gears, a locker, nitto drag radials, and spraying a 100 hp shot with the timing @ 0* (imo the base timing on these cars doesnt really matter as long as its close to 0* bc the computer is gonna do what it wants with it based on what the knock sensor is telling it) my car ran 8.90's on just motor and traction limited 8.20's with the n20. i spray right off the line and hold it till the end. my 60ft times are high (2.2 on motor, 2.0 on n20) bc my track just opened and they dont treat it for t&t. as for mph 80 mph on motor and 90 on spray. hopefully as the track gets better throughout the summer i will be able to hook better and drop a tenth or 2 off my times.

 

the best was 8.70s on motor was goin tomorrow but rained the track out so after a week of anticipation i guess its back to drawing board this week there open next saturday so we ll see i just bought a set of 255/50/60 bfg drag radials and put them on my irocs so ill see how well it hooks planning on gettin a 2800-3200 converter and maybe ditching the 3.23s i paint so ill have to do some swaping and come across a few after hour jobs to get some more goodys

 

IF it stalls near 3200 on the spray, it should leave in the 1.6's 60 foot if it hooks. Its gonna come off the line hard! My bolt on L98 ran 1.71s with a 2800 stall so nitrous would easily gain a tenth

 

that would sure be a nice sleeper in a world of ls1s most people around here dont even pay much attention to these cars since they are old tech that is till it runs down the track against a newer ls1 ive had ls1cars,lt1cars two thirdgens and even a 69 camaro in my life and i have to admit i didnt respect the tpi cars till i bought this one... its been a blast and i sure do like it it has suprised several of my buddys mustangs and i hope to keep that up i would like to later down the road do a 6.0 swap but we will have to see.....

 

I agree with the 2*/50 timing retard. I went 1 step colder on the plugs also, gapped at .030 Pulled 6*, ran a 150 shot more times than I could even attempt to count with no problems.

 

If you ever upgrade to a different motor with good heads you can get away with only a few degrees pulled with a 150 shot. My 383 made best power on motor at 34 deg timing and on 150 shot juice I ran 32 deg with a air fuel in the mid high 11's to 1. Best to start out lower and bring it in slowly only if the motor can take it.

 

running the 150 shot I had mine at 30* total with a/f at 12.0-12.1

 

just from my personal experience on my 305 car, i ran a 100 wet shot through a spray nozzle in the intake all i did was put in some r42ts AC delco plugs and 91 (best i can get out of the pump here) and ran it. plug looked good, timing mark was right to the bend on the strap. personally i would pull 2 degrees and read the plug and see where to go from there

 

I would say if the car is stock he could run premium gas and pull no timing. Just throw in some colder plugs. The NOS 150 kits could be ran with no timing pulled. But if the car has a chip or base timing has been advanced then yes you will have to pull timing.

 

adjust timing back 2 degrees every 50 shoot

 

PRIMARY QUESTION, do you have an aftermarket chip? What's your base timing set at right now with the EST unplugged?