12 valve questions
 

does anyone know what size injectors i can get for my 91 12 valve.the biggest ones i can find are only 40 or 50 horse do they make em any bigger please help me blow some serious smoke

Hey Bigrich. Welcome to the site. I moved this here so that it would get better exposure from the members who know your truck the best. Make sure you fill out your signature so they can see exactly what you have and what other things you have already done to it. This helps them answer your questions better.

DDP stage IV is about the biggest you can get, is your rig a intercooled or non intercooled? by the way welcome to the site

well, ddp stage iv is the biggest "listed" but there r much bigger sticks. Custom EDM obviously, but that all depends on your wallet.

do the 2nd gen injectors work in 1st gens

Second gen injectors don't work on first gens; they operate at too high of a pressure.

As for first gen injectors, there are two breeds; until 91.5 there were 9mm injectors stock, after that there were 7mm injectors stock. The 9mm injectors can support 300 HP with a maxed injection pump. Depending on your goals, that might be enough.
All off-the-shelf aftermarket injectors are 7mm; they can be used in the earlier trucks, but they require an adapter. The Bosch 190's, which are often labelled as "40-50 HP" injectors, are a 7mm injector that flows about as much as the earlier 9mm injectors.
The most prolific performance-minded injector in the first gen community is the Lucas Prince of Darkness (POD) injector. They cost $400 and support 350-400 HP, but some are really sloppy and smoky.
After POD's, most people in the big-power arena jump straight to customs. I think Dynomite Diesel Performance used to make bigger off-the-shelf injectors, but their website doesn't show them any longer. Somebody probably has something out there, but it'd be news for me.

keep in mind that adding fuel like this will require more air = TURBO

As long as you have a pyrometer then you can add fuel for quite a while, you just won't be able to keep fueling for as long without a modified turbocharger.

Buddha power built some big custom sticks for KTA Cummins I believe, he has a set for sale but they are big money.

Andy

Yeah i think it was buddha or new era that built em 600+ hp! second injectors do not work, but the nozzles do, however they r a little different pattern, n spray somewhat out of the piston "bowl" but they will work, the injectors have to takin to a shop and repoped though. Off the self, r the rv's, and PODs. PDR has their offerings that they list, off the shelf i dont know. but custom cut, not listed, gotta call n ask, r our options after like 50 ponies.