Tuning Question

Hey guys. I have a jet boat that had a Sniper kit on it when I bought it. BBF of course. Anyway, he told me it was set at a 100 shot but it never worked right. I set the total timing at 30 degrees running Autolite 25 plugs and took it out. I didn't stand on it out of the hole but mashed the pedal activating the switch at about 55mph or 4500rpm. It picked up... A Lot.... but started sputtering right away. So I shut it down and drank beer with hot chicks. Lol.
Here's what I found:
*I have 073 nitrous and 082 fuel jets. I guess thats for 175 shot from what I've read.
*My plugs look really clean.
Is this a timing issue or low fuel pressure/both? The fuel pump is only a mechanical feeding both the carb and plate thru a T fitting. I'm trying to make this work right without breaking the bank.
Thanks!
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the manual pumps dont seem to be up to the task ive run the holley without much luck. so i added a elec. pump holley blue just for the nitrous. the bigger tune ups need race gas or more timing taken out of them this is a tune that works on pump gas 42nitrous 36fuel 5psi fuel pressure with 30* total timing its around 50hp but runs like a 100 Monty Smith gave me the tune its bad ass. here's a 150hp tune 65n 52f 5psi fp 28* total timing with race 24* with pump gas

forgot the plugs the 50hp you can run your plugs with the 150hp you need a retracked tip plug around a 9 heat range in a ngk

X2 on the pump, and that is a pig fat tuneup, and the timing may be trying to compensate for it. By plugs being clean what do you mean? Where is the timing mark on the strap? Where is the fuel mark on the porcelain?

Swap. The tune and hang on

and get a better fuel pump........

Swap? Not sure what that means. I'm a newbie. So you think a Holly black pump will run the motor and NOS at this 175 shot? I ran 1/2 line all the way from the tank up front.
Also, is it possible to back it off to like 100 shot without replacing the fuel pump and get some cooler plugs?
Thanks again everyone!

73n 82f...............swap to a 82n 73f

a Sniper kit is not made to flow more than 150 hp worth of nitrous a 71 on the nitrous side is about as far as i would go. the person who offerd the 42 nos 36 fuel jet tune up would be what i would try first Just my .02

Ordered a few different jets today. Going to try the 42n 36f and see how it responds. Do you think the stock fuel pump be enough for that small of shot?
I'm thinking about replacing the fuel pump with an electric to run both the motor and kit. I would like to see a 150 shot tuned in properly. I've got some outboard guys that want a piece of this old tub. Haha

Thanks again guys!

yes the stock pump should be fine for that hit.

Sounds like your heading in the right direction. I agree if the pumps in question either replace or go with the smaller shot to be safer. Also as the others are telling you to get the tunes correct the nitrous jet will need to be bigger then the fuel jet.. It is not uncommeon to need 10-20 numbers to get these things where they really need to be, especially depending on your fuel pressure.. Thanks, SJ

Thanks everyone! I just got my assortment of jets and am heading out shortly. I will let ya know how it goes.
Thanks again for the help.