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400hp build ?

77K views 49 replies 22 participants last post by  glowplug 
#1 ·
I've been talking with a local cummins certified diesel mechanic about building a 400+hp p-pump 12v. He says with proper engineering, he can make it run like a factory engine, as far as egt's, smoke, etc. The engine I'm starting with is basically a core, so were talking total rebuild. He's quoted me for sleeving and boring the block, rebuilt head with valve job and hardened studs&90# springs, oil pump, water pump, bench tuned for 400hp rebuilt injection pump&injectors to match, and rebuild kit. 9600 in parts,1600 in labor. So my questions are, is this a decent price. And any recommendations on a company that builds a good solid 47rh that can handle amn engine like that.
Any epxerience apprecciatted! Doug
 
#2 ·
for tranny look a dave goerend. this is what i would do for 400hp. sdx90hp injectors, 62/65/12 turbo, 4k gov., take the plate out of fuel pump, head studs, heaver exhaust valve springs, marine head gasket, tune the afc housing. fix the kdp. that setup should put you over 400hp maybe 500hp and set your pump timing to 16 degrees
 
#3 ·
$10k plus in an engine...for 400 hp??

you could get a junkyard engine and with very little mods and a good turbo you could easily hit 400hp and have it tuned in to run as clean as a stock motor. motor would easily last 500k miles

heck I could detune my motor to 400hp and gove you my whole truck for $10k
 
#4 ·
^ That's what I was thinking. I would source out all your options first using that 10K budget. You could potentially buy a whole truck for that so is it worth 400hp and do you need 400hp that bad? I've built a few motors though not diesels but to me Its a bit steep in my opinion for what your getting (I could be wrong) On the plus side its a completely new motor and you will know what's in it from the get go. Seriously 10K plus :vomit007:
 
#5 ·
Really shooting for the moon, aren't ya?

I'm gonna go out on a limb and say that you can tune a stock 215 pumped truck to 400HP without the help of any big budget items.

Governor springs, no plate, AFC tuned properly, and a clutch to hold it all together and you'll be knocking on the door pretty hard.
 
#6 ·
just look at the mods in my signature and i only spent 300 dollars.
 
#7 ·
Ill sell you my whole truck for $9600 and it did 540hp on 370's now it has 5x16's. That's just alot of money for nothing I did 389 in my old 96 with a clutch, tuned pump, and stock tightend gov springs. It's a good thing you came and asked first!
 
#9 ·
Thanks for all good feedback guys.I know only a few mods are necessary to push a p-pump 12v up to 400hp.I'm talking about buiding an engine from one I bought used that had been overheated with around 100,000 miles on it.It's going in an 89' suburban project truck that I already have a 93' 12v ve pump in and running, this engine only has 70,000 miles on it, not even an oil leak yet, so I don't wana start turnin up this engine. So I decided to build virtually a new engine from the p-pump core I bought.I was told the engine was shut down as soon as it got hot but I see antifreeze stains all over on block underneath exhaust manifold, so before I go trying to make big power in a truck that I want to be very reliable I figure I should start at the bottom. I'm just not that skilled with the internals of an engine, so I'm looking for some feedback on anyone with experience with a good trust worhty engine builder I can have build a good reliable 400hp 12v engine in the nothern CA, southern OR, or western NV area? Once again, I appreciatte all thefeedback
 
#12 · (Edited)
shoot, you could just buy any of these members trucks like they said for less than 10k and over 400 hp and part the rest of the truck to make a lot of your money back. 10k is way too much for a rebuild and 400 hp. just buy an engine on craigslist and go from there.
 
#11 ·
Im thinking it would be best for your situation to find said used motor and then build that. OR, you could go a different route with that overheated motor by taking the head off and taking it down to the machine shop to have it checked out for cracks or warp. IF it checks out good the bottom end should be just fine, its the head that will go belly up due to heat before anything else. Then you can have them do some head work or just bolt it back up with ARP hardware, marine gasket and heavier valves. It would be much cheaper either route then having the whole motor rebuilt just because, but Im sure the machine shop would love to make the money on it.
 
#14 ·
i'm with everyone else on here. that seems really high. some small injectors and a turbo with supporting mods would make the truck just as reliable as stock with 400 hp. i would consider putting a fuel plate in it tho. i ran no plate for a while and i was struggling to get the afc tuned in properly. the truck bogged off the bottom and dumped full fuel with 10 pounds of boost. poor tuning? maybe. but i just dropped a #10 fuel plate in there after i got home from school and it spools off the bottom with a lot less smoke that before. but ten grand seems high. parts alone for a 400 hp build couldn't be more than three grand. that would be including a turbo, injectors from sdx, headstuds, a new head gasket, valve cover gaskets, o-ringed head, ported and polished head, and some other things. lol. i know you said you don't really wanna work on it yourself but you should really consider it. these things are really easy to work on.
 
#15 ·
All great feedback guys, MX26 the ve pumped engine is gonna get lightly modded and dropped in my 72' Suburban othrwise that wouldbe a great idea, thanks to good reference from this site I found a guy in Redding CA just a few hours up da road from me, who's willing to work on my engine for a much more reasonable price. Thanks again, Doug.
 
#17 ·
Everybody else has said the same thing I'm thinking, but I'm in a silly mood, so I'm gonna pile on:

Buy a plane ticket to Afghanistan if you can. Fly out there, and buy/steal/trade every goat you can find. Grease everyone's palms in customs to the tune of a couple thousand dollars to get all these goats back to the states. Buy an assload of rope and tie all these goats to your suburban. Pay a bunch of midgets to whip the hell out of the goats to get them going.

If you get enough goats you'll probably have 400 hp worth of them, and you'll probably still come out cheaper than 10 grand.
 
#20 ·
If you get enough goats you'll probably have 400 hp worth of them, and you'll probably still come out cheaper than 10 grand.
Call me ignorant, but what is the equation for converting HP to GP?
 
#28 ·
i use the same hx40 style dp everyone else uses and yes the ebay one
 
#22 ·
isn't it 2 1/2 goats per horse? if i'm wrong please excuse me, i was sober.

rande
 
#26 ·
You guys are right on the HP vs GP ratio. What's really bad is when you use rabbits. The HP to RP ratio is something like 1:900. Thing is, if you start with 2 rabbits it doesn't take that long to end up with 900.

On the chinese turbo, if by "it's as good as a holset" you mean "it hasn't blown up yet" then that's believable. If you mean that you actually expect the same life and think it's as well made as a holset, then there's a guy on dieselram.com that you might not like to talk to. He's cut some of the chinese exhaust housings apart with a band saw to see how the castings are. He's also cut some holset housings apart. Guess which was smooth and properly shaped inside? I found this out when I was searching for info on exhaust housing options for my buddy's '92, and he set me straight on exactly why I would not want to recommend he get a cheap housing. Basically, there are things that you can skimp on quality-wise and get away with it for a long time. Unless you're very lucky, this is not one of them.

Now, I'm not knocking you for trying a cheap turbo out. Just understand that it's highly likely to not last nearly as long as a holset, everything else being equal. I'd expect that it won't hurt your motor if it comes apart-intercoolers make very effective shrapnel catchers. I mean that in all seriousness-most motors I've heard of that swallowed compressor wheel parts were not intercooled. They were also gas motors, but you get the idea.
 
#27 ·
I'd expect that it won't hurt your motor if it comes apart-intercoolers make very effective shrapnel catchers. I mean that in all seriousness-most motors I've heard of that swallowed compressor wheel parts were not intercooled. They were also gas motors, but you get the idea.
I'd also expect you've never actually blown a turbo up then, am I correct? When that thing explodes......its gonna go right through the intercooler and strait into the motor. Chinese........fried food=good, turbos=bad.
 
#33 ·
wow...for 10k you should be gettin 500hp at least...i did ne way..my .02..better yet for 10k ill sell you a 400hp truck and give you some change...
trust me...Im a lawyer.
 
#41 ·
well they've been lucky, it doesnt always happen but it happens more times than it doesnt. Sadly most of the time they still run fine, its just when you pull the head that you find all the crap that got stuck in the pistons.
 
#47 ·
an hx40?? id say they could prob handle what, maybe 2700 rp or 3hp:)
 
#48 ·
i got 12grand in mine pushing over 600 with a stock tranny
 
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