Where to take my pump? stay twins or go single?

Lucky Jeff

Lucky Jeff

Stock Sucks
Joined
Apr 3, 2007
Messages
5,784
I decided to rip the motor out of my truck and rebuild it. I've been wanting to clean up the engine bay and the engine for a while and re-route all the harnesses (I don't like seeing them). I know I need to have my pump worked on. I can only imagine it's my problem. With my DDP3's+, .024 DV's, BD's towing twins and an oddball plate I ran in the 460's. With a II62 I ran 414 with the same injectors and 024 dv's (450's with stock dv's). I ran 417 with DDP4's+, stock dv's and a SS64. There is only so many things that can cause that much of a power problem. I'd have to assume it's the pump.

And if I can get all of that figured out. With all of these guys running low 500's no problem with 62's and 64's I'm thinking about going back to a single just for simplicity since the small twins can only manage to support the same. Anyone think differently?

So any suggestions on where to go or what else to do in there is appreciated..
 
If you want to make low 500s probably a small s300 for you. If you want lots more and aren't worried about spool as much i'm offloading my 468 for to start a twins build.
 
Don't need much more then the low 500's.. I use this thing too much for towing/hauling.. It's manual so I never planned on setting it up for drag racing. Just like to play around :Cheer:. And I hate lifting, so heat's going to be my main concern.
 
The last place I'd call would be about 60 miles north of you. :doh:
 
I would definitely send the pump out for a bit of tweaking. It doesn't hurt how they drive, just makes more power. If you want power without heat, twins are the only answer. No single will hang with them on a long pull. Too bad you're not closer. My 887 is just sitting in the box right now. I made over 700 easily with it and 181dv's. It would at least give you food for though as to whether it was worth the extra expense.

Ron
 
RonA said:
I would definitely send the pump out for a bit of tweaking. It doesn't hurt how they drive, just makes more power. If you want power without heat, twins are the only answer. No single will hang with them on a long pull. Too bad you're not closer. My 887 is just sitting in the box right now. I made over 700 easily with it and 181dv's. It would at least give you food for though as to whether it was worth the extra expense.

Ron
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I'd definitely like to run it. But the motor is two bolts away from coming out now, heh. And I don't need the pump modded too much. Just want to figure out what;s wrong with it.. I can't picture it being anything else with that much of a power problem. There are only so many parts to a 12 valve. And it seems that most singles are better then the twins I have. Don't really feel like spending another 4600 on a different set of twins. :bang
 
DTanklage said:
have ya leaked the motor down to determine its not a mech problem?
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Nope I haven't.. and it's a possibility. I'm kinda thinkin it's been this way since the headgasket blew a few years ago... At least I won't have to climb up onto the truck to do it :rockwoot:
 
thats always the first thing i do if something is down on power

rule out a mech problem before unnecessarily changing out good parts

had one last year that really had me chasing my own tail

the thing was sealed up really good but would miss at the top of every gear

sounded exactly like a blown head gasket but as stated it wasnt

actually the problem did eventually kill the head gasket but that was not the cause of the miss but rather the result

i was pullin my hair out

changed every ign component

twice

put 3 different sets of carbs on the thing (7.90 top gas motor)

know what it ended up being?

those motors use a press together crankshaft, right? (old kawi from stone age). well when i have the cranks built i have my crank guy put a deep bevel on ea journal and weld them together. this particular crank tho, i had him pin the mains cuz it was a spare for the pro mod. they drill a hole thru the throw and press a 1/4" pin in before welding. that way even if you break a weld the crank cant spin on you. (if it spins valves hit pistons and it gets real expensive so this is kinda cheap insurance). well the stupid thing had cracked a weld (yea, in a top gas app, no nos, who woula thunk?) and the pin was the only thing holding it together. i had checked the cam timing and everything was perfect but as soon as that thing hit about ten grand it would start walking back n forth and was messin everything up. cam timing would be off on two cyls and ign timing off on the other two! but it only had like 2% and the cam timing was right so i never thought it could be a mechanical problem

sorry for the book - went to taco bell late tonight - their pepsi is laced with meth, i swear

even if you leak yours down and find bent valves or somethin leakin somewheres req rebuild i would still send the pump out cuz like ron said you will get some power outta it and you will know its right and who knows.,..might even get better mileage as a result

speaking of which how effecient has it been since you replaced the head gskt?

maybe they had to take a bunch off the head to get it flat again and didnt use a thicker gasket?

insufficient valve to piston?

i dont know...just thinkin out loud

hope you post your findings cuz i am curious what it is
 
I'll have to see if I can locate a leak down tester first and let you know what I find.. The guy did a valve job and surfaced the head, but said he didn't need to take off much. Wouldn't make me too happy if he botched the valve job that's for sure.
 
You know i'd like to do a leak down test myself to see where i'm at. Anyone have one they wouldn't mind renting out?
 
i have some inj bodies for a ve i dont need

you could cut the top off of one and make an adp if you have access to a welder

then all you need is a reg and a couple of accurate gauges

most dont like to loan out their tools

know i dont

dont buy a cheapo - if the gauges are not really accurate it can make a good motor look bad and vise versa

really better off to build your own
 
DTanklage said:
hope you post your findings cuz i am curious what it is
Click to expand...

Ok so I finally got a leak down tester and hooked it up..
1 - 5%
2 - 15%
3 - 25%
4 - 17%
5 - 12%
6 - 12%

2, 3 and 4 were leaking air out of the exhaust port. Took the studs out after wards.. Studs that were under the valve cover seemed fine. A few of the others were pretty ugly (gunk, not sure if that's normal). And one near #1 has cemented itself in there. Have penetrating oil on it now. Also found a split in the head gasket on #5.. If my camera didn't just crap out I'd take pics. But oh well, I'll borrow one tomorrow or something.
 
Wow that was quick I was just there and you already have the head off?
 
Lucky Jeff said:
Ok so I finally got a leak down tester and hooked it up..

1 - 5%
2 - 15%
3 - 25%
4 - 17%
5 - 12%
6 - 12%
Click to expand...

ouch

ps - i got a head sittin here ready to go if you are in a bind (and rich)

tanked n mag'ed ported n polished surfaced sick ass valve job .011 protrusion ss wire big springs etc all new
 
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