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GSK and Marine Injectors.

4K views 20 replies 8 participants last post by  jkidd 
#1 ·
alrighty, my boss and me figure its an injector that crapped out(#4 to be exact since its exhaust runner temp was 450*F when the others were 300 at idle) so im looking up injectors and found that 50 horse ones were 20 dollars more than 370 horse marine injectors. is there something wrong with them where they wont work on the street? will it idle like trash and not run right with them in there? if theyre like 6.2 marine injectors they have a lower pop presure so they dump more fuel in without burning it properly at lower revs right? and i figured id get myself a 4K GSK with valve springs while im at it afterwards. from what i read it makes the truck much more snappy and easier to drive since it doesnt top out at 2200 RPM anymore( mine tops out at 2200 in gear and 3200 in neutral so i dunno WTF is up). so should i just get 1 stock replacement injector for #4?(i dont think i would since the condition of the other 5 is unknown) or buy 6 new stockers or 6 marine ones or 6 50 horse ones?
 
#2 ·
nothing 'wrong' with the m370s. Of course they arent the best choice as they are obviously intended for a marine application and thus have a wide spray angle.

All in all, if your using a thin sealing washer and your timing is reasonable, they are actually a good 'bang for the buck' injector.

Keep in mind, that a 'properly' set up injector will obviously improve efficiency and power over that of an 'off the shelf' marine injector.

As for just replacing the one injector, thats a possibility, but shouldnt be done unless you pull the other 5 and have them re-shimmed. If you dont, you are going to have 5 injectors with a lower pop pressure than the new one. which means, that new injector is going to cause that cylinder to fire 'retarded' in relation to the rest of them (higher pop pressure = lower timing) which is going to cause some running issues.
 
#3 ·
well the local diesel shop wants almost 100 bucks a piece to test, repair/reshim the injectors, so fixing them is more money than new injectors. i was gonna order the 370's but theyre on backorder for one thing and i wasnt sure if theyd work. so with them installed id get more smoke, and probably higher EGT's(both a downfall unless you love huge coal clouds all the time, which i do on occasion ;) ) but would they light the turbo any better? im going to see what my boss says for injector prices from his supplyer, if he can get stockers fairly cheap thats what it will get but if i have an excuse to put in big foggers why not right? :D
 
#5 ·
Seems like a lot of folks here have complained about too much smoke with the marine 370s.
Bet there are a bunch of them in the classifieds here.
Or you could post a want ad there and will probably find some with low miles and even cheaper than what you're looking at.
 
#6 ·
Check out diesel auto power (dot) com. They have "370s" but with the correct 145* spray pattern. $250 + core charge.

I have some kind of 300-370 hp marine injectors in my truck, and they will smoke a f*ck ton even with stock DVs and moderate AFC settings. You'd be a fool not to go with those DAP correct spray 370s.
 
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#13 ·
I just checked those out, and they raise a couple of questions for me. I have a set of 370's I got from Pier's a few years ago. It's a safe bet they're the dirty ones, right? Other question-have any of you guys tried the clean ones being talked about? How were they? (I'm considering asking for them for Christmas.)
 
#8 ·
well if i can find some that arent on freaking back order i guess ill get some. when you say smoke you just mean black on acceleration right? because i can live with that, what i dont want is a thick blue haze at idle(little tinge i can live with) or greyish smoke while driving.
 
#9 ·
I dont know if my afc is decently tuned, but with the 370s and timing, mine really dont smoke that bad. It used to be way worse with just the pump mods and stock injectors. She will leave a little black cloud(till turbo lights) when I floor it from a dead stop than its just a light haze through the gears. Cant say I love them, cant say i hate them but I got them for free and I am pleased with them for now.
 
#10 ·
your AFC must be tuned real nice if it dont smoke too aweful much with no plate and marine injectors.
 
#12 ·
the m370s (depending on the setup) will haze lightly at idle and again, the smoke under acceleration is going to be a tad more than what you would see from a 145* injector

Alot of variables come into play, but for the most part its the goofs that throw a set of m370s in their truck, gut the afc and are running a stock turbo that whine about them being too smokey
 
#14 ·
well im starting to be turned towards some 140 horse injectors. they seem like a better idea since im running a stock clutch and i know if i have marine injectors ill try and use all of the fueling they can offer lol.
 
#16 ·
x2, those 140s (5x014) are going to be ALOT of injector unless you have the air to feed them


I would not think twice about a set of decently priced m370s, they are going to be a it dirty on a stock hairdrier, but with a little more air they clean up nicely
 
#17 ·
wouldnt backing off the plate work alright? i have it FF with a custom grind on it so im sure id have to back it up a fair chunk to keep from melting my clutch and some pistons.
 
#18 ·
I know what you mean on the smoke. I can just about literally turn day into night if I whack it from low rpm. So, I don't make a practice of doing that, but it would still be nice to not turn that much fuel into smoke.

If I remember correctly, the price on the marine injectors with the right spray pattern is $250. Is this for new injectors? Also, I wonder if I sent them my current incorrect-pattern 370's if they'd put tips on them to give the correct pattern for less money?
 
#19 ·
I am getting more tips flowed and matched. I will be able to offer more intermediate steps for injector sizes with the correct spray pattern (and even some for the 1st gen guys with 9mm tips)

For the guys up in Canada I can help out with shipping and GST/HST(I think they will fit in a flat rate small box for priority mail).

The 370's for $250 are aftermarket bodies. They are about .0125 x5 and would be equal to about 390HP. They are flow matched and pop tested.

I do have more options than what is listed on my website.
 
#21 ·
370's are considered to add 50-90HP depending on what you are replacing (the 215HP engine came with 5x.010 instead of 5x.009 so the truck upgrading from 5x.010 injectors will only see about 50HP)

The injectors mentioned will do about 15-20HP more than standard 370's
 
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