I personally wouldnt use the 12 cm, its to restrictive top end. The 16 is the choice of most in the old trucks. Plus the wastegate does nothing for spool. All it does is control boost by bypassing the turbine. Id plug the wastegate and run it wide open, as the boost is controlled by fuel delivery. 25 psi is plenty safe, I ran that for years. Also the 93s didnt have a 21 it had a 18 cm if it was stock. The late 91s and 92 had 21 cm housings. In my 93 I have no wastegate and a 16 cm housing and I just let it run wide open. I am considering puttind the 18 back on as I lost 2 psi with the 16cm.
how much boost?
running a 93', changed the 21cm out for a 12cm with a wastegate for quik spool. Pump is turned up but mostly stock. What PSI can I run safely? I heard 24 once on the stock turbo, don't know. I figure I would grainger it. It is an auto trany.
Rob
Rob
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I know the wastegate itself doesn't help spool up, but a smaller turbine with a wastegate from a newer truch does effect spool up. The truck lags hard and the boost is real low. With an auto it spools super slow and takes off like a school bus. 25 PSI? I will make sure it makes that then.mopar2ya said:I personally wouldnt use the 12 cm, its to restrictive top end. The 16 is the choice of most in the old trucks. Plus the wastegate does nothing for spool. All it does is control boost by bypassing the turbine. Id plug the wastegate and run it wide open, as the boost is controlled by fuel delivery. 25 psi is plenty safe, I ran that for years. Also the 93s didnt have a 21 it had a 18 cm if it was stock. The late 91s and 92 had 21 cm housings. In my 93 I have no wastegate and a 16 cm housing and I just let it run wide open. I am considering puttind the 18 back on as I lost 2 psi with the 16cm.
I assume you cut the crimp from the fuel screw and turned the aneroid down correct? You can also have a shop set the pump timing up to 1.45mm, no more than that though.
mopar2ya said:I personally wouldnt use the 12 cm, its to restrictive top end. The 16 is the choice of most in the old trucks. Plus the wastegate does nothing for spool. All it does is control boost by bypassing the turbine. Id plug the wastegate and run it wide open, as the boost is controlled by fuel delivery. 25 psi is plenty safe, I ran that for years. Also the 93s didnt have a 21 it had a 18 cm if it was stock. The late 91s and 92 had 21 cm housings. In my 93 I have no wastegate and a 16 cm housing and I just let it run wide open. I am considering puttind the 18 back on as I lost 2 psi with the 16cm.
No offence, but what are you talking about man??? The 12cm housing is not gonna be restrictive at all on an old 12 valve making only 200 HP. Leaving the wastegate plugged on the 12cm housing is also a bad idea.
Boost has very little to do with power output on a diesel. More fuel=more power you only need more boost to keep EGT's down. Yes diesels work opposite of gas engines more boost lowers EGT's. You need an Pyrometer and set your boost at whatever you have too for good power (1300-1400 degrees in the manifold, if you put the probe after the turbo deduct 300 degrees). You can run 35 PSI on your truck as is and nothing would happen, no more power because you need fuel.
A tip for faster spool-up is to get a larger exhaust system. Your stock exhuast is way too tiny I believe in those years it was only 2.5''. Get a minimum of 3'' mandrel if not 4'' if you can find it to lower EGT's and faster spool-up.
But, the turbo itself is good to atleast 30 PSI minimum. So if you want to upgrade later to say the lucas injectors (65 HP) you'll have enough turbo there to compensate. 30 PSI is probably just about right for those injectors and your pump turned up.
my truck is an auto, spool is super slow, the 12cm will be nice. Then power will not get pushed too much, K&N and a straight through muffler on an already 3" factory system. 25 then is a good PSI to go with? From what I hear if I add fuel it will be the POD injectors, good price to power ratio. But otherwise I want the truck to take off quikly and not be a slug for a month till boost hits.moparzrule said:No offence, but what are you talking about man??? The 12cm housing is not gonna be restrictive at all on an old 12 valve making only 200 HP. Leaving the wastegate plugged on the 12cm housing is also a bad idea.
Boost has very little to do with power output on a diesel. More fuel=more power you only need more boost to keep EGT's down. Yes diesels work opposite of gas engines more boost lowers EGT's. You need an Pyrometer and set your boost at whatever you have too for good power (1300-1400 degrees in the manifold, if you put the probe after the turbo deduct 300 degrees). You can run 35 PSI on your truck as is and nothing would happen, no more power because you need fuel.
A tip for faster spool-up is to get a larger exhaust system. Your stock exhuast is way too tiny I believe in those years it was only 2.5''. Get a minimum of 3'' mandrel if not 4'' if you can find it to lower EGT's and faster spool-up.
But, the turbo itself is good to atleast 30 PSI minimum. So if you want to upgrade later to say the lucas injectors (65 HP) you'll have enough turbo there to compensate. 30 PSI is probably just about right for those injectors and your pump turned up.
I know what Im talking about I own the same truck he's trying to mod.
Ive run a 12 cm and 16, both cut my top end power by 2 psi, if you dont believe me talk to James Ray he worked for Cummins for 15 years and was the senior tech on the Dodge Land Speed Record truck a number of years ago, we installed it at his house in TN. So dont tell me what I know, I didnt get my info from some forum or article.
More fuel doesnt mean more power without the boost. The fuel means you can make more boost to use more air. Any 1st year engine guy knows it takes air and fuel to make power. 1300-1400 in the manifold, man your flirting w/ disaster, Cummins says 1280 in the manifold it the shutdown point, perhaps a quick blast to 1400, but if you pull anything you better not play around up there to long.
Again 30 psi minimum, guess what the turbo is doing pushing that hard? Heating the air which raises EGTs, will the turbo do it yes it will, is it efficient not really. There are certainly better compressor wheels you can add for a few hundred dollars.
Finally, more boost doesnt make lower EGTs, what crazy idea is this? Do you own a diesel or just hang out on the forums?
POPE, it doesnt sound like you want a purpose built towing rig. Try this, cut the crimp off the fuel screw, crank it in all the way, next on the top of the pump you will see 4 screws holding down a plate, in the middle is a nickle sizes cap, use a small screwdriver and pop it out, loosen the jam nut and turn this down till it stops. Next go take it for a spin and hammer it. We did this same thing on my ex-father in laws 92 Auto and it was one fast truck. Ive done this same thing to at least 2 dozen over the years, in fact in Indiana I did it on a guys truck and he smoked a Banks stage 2 truck and the totol cost of the mods was he bought me lunch.
This is also a good way to see if your pump is any good. These things had big QC problems, if you truck wont do 20+ psi with the fuel cranked up its not a good pump. I dynoed mine at 260 something and 600+ tq with only a cranked pump.
Ive run a 12 cm and 16, both cut my top end power by 2 psi, if you dont believe me talk to James Ray he worked for Cummins for 15 years and was the senior tech on the Dodge Land Speed Record truck a number of years ago, we installed it at his house in TN. So dont tell me what I know, I didnt get my info from some forum or article.
More fuel doesnt mean more power without the boost. The fuel means you can make more boost to use more air. Any 1st year engine guy knows it takes air and fuel to make power. 1300-1400 in the manifold, man your flirting w/ disaster, Cummins says 1280 in the manifold it the shutdown point, perhaps a quick blast to 1400, but if you pull anything you better not play around up there to long.
Again 30 psi minimum, guess what the turbo is doing pushing that hard? Heating the air which raises EGTs, will the turbo do it yes it will, is it efficient not really. There are certainly better compressor wheels you can add for a few hundred dollars.
Finally, more boost doesnt make lower EGTs, what crazy idea is this? Do you own a diesel or just hang out on the forums?
POPE, it doesnt sound like you want a purpose built towing rig. Try this, cut the crimp off the fuel screw, crank it in all the way, next on the top of the pump you will see 4 screws holding down a plate, in the middle is a nickle sizes cap, use a small screwdriver and pop it out, loosen the jam nut and turn this down till it stops. Next go take it for a spin and hammer it. We did this same thing on my ex-father in laws 92 Auto and it was one fast truck. Ive done this same thing to at least 2 dozen over the years, in fact in Indiana I did it on a guys truck and he smoked a Banks stage 2 truck and the totol cost of the mods was he bought me lunch.
This is also a good way to see if your pump is any good. These things had big QC problems, if you truck wont do 20+ psi with the fuel cranked up its not a good pump. I dynoed mine at 260 something and 600+ tq with only a cranked pump.
I am new to diesels, do you have a pic of where these are? Will this thing finally spool up? I do tow with it, but I also build torqueflights so I can mod it to take more fairly easy. But everyone seems to think the pump should only be cranked 2 turns though? Is this second screw something that effects this?mopar2ya said:I know what Im talking about I own the same truck he's trying to mod.
Ive run a 12 cm and 16, both cut my top end power by 2 psi, if you dont believe me talk to James Ray he worked for Cummins for 15 years and was the senior tech on the Dodge Land Speed Record truck a number of years ago, we installed it at his house in TN. So dont tell me what I know, I didnt get my info from some forum or article.
More fuel doesnt mean more power without the boost. The fuel means you can make more boost to use more air. Any 1st year engine guy knows it takes air and fuel to make power. 1300-1400 in the manifold, man your flirting w/ disaster, Cummins says 1280 in the manifold it the shutdown point, perhaps a quick blast to 1400, but if you pull anything you better not play around up there to long.
Again 30 psi minimum, guess what the turbo is doing pushing that hard? Heating the air which raises EGTs, will the turbo do it yes it will, is it efficient not really. There are certainly better compressor wheels you can add for a few hundred dollars.
Finally, more boost doesnt make lower EGTs, what crazy idea is this? Do you own a diesel or just hang out on the forums?
POPE, it doesnt sound like you want a purpose built towing rig. Try this, cut the crimp off the fuel screw, crank it in all the way, next on the top of the pump you will see 4 screws holding down a plate, in the middle is a nickle sizes cap, use a small screwdriver and pop it out, loosen the jam nut and turn this down till it stops. Next go take it for a spin and hammer it. We did this same thing on my ex-father in laws 92 Auto and it was one fast truck. Ive done this same thing to at least 2 dozen over the years, in fact in Indiana I did it on a guys truck and he smoked a Banks stage 2 truck and the totol cost of the mods was he bought me lunch.
This is also a good way to see if your pump is any good. These things had big QC problems, if you truck wont do 20+ psi with the fuel cranked up its not a good pump. I dynoed mine at 260 something and 600+ tq with only a cranked pump.
I dont have a picture, but I can do my best to tell you. The fuel screw which is where the power is at, is on the back of the pump if it hasnt been messed with has a tin cap that has a taper to it thats about 1.5 inches long and mabe 1/2-1/3 inch wide. You need to remove this cap which can be done with a long screwdrive and prying it off or you can grap it will a pair of side cutters and tap the cutter with a hammer, it has a tang that keeps it in place. Once the cap is off you will see the screw, remove it by turning it CCW, a few tablespoons of fuel will dribble out, no big deal there. You will see a crimp that has a tack weld surrounding the threads, use the side cutters and remove it, it not as bad as it may look. Then reinstall it all the way, this is full fuel. Then do the other adjustment I mentioned earlier, this is the aneroid valve which ramps the fuel in. Your idle will be about 500 rpms higher so you will need to turn the idle screw which is on the top front of the pump, loosen the jam nut, I use a long screwdriver and a hammer to loosen the nut, and adj the idle by turning screw. With the fuel cranked up when you stomp on it it will give a good huff of smoke and as soon as boost comes on will clear right up, if its a bit more smoke turn the screw back out 1/2 turn until its where you want it. The smoke is kinda fun at stop lights when a anoying SOB is next to your exhaust pipe.....
It will be best to install a EGT if you pull much with the fuel up all the way, but if your pump is decent internally, you will be all smiles when you first stand on it. Ive run my truck over a million miles with the same mods I just described.
It will be best to install a EGT if you pull much with the fuel up all the way, but if your pump is decent internally, you will be all smiles when you first stand on it. Ive run my truck over a million miles with the same mods I just described.
Just cuz you own the truck doesn't necessarily mean you know a lot about it. I see obviously you do for the most part, but making that statement is just dumb because just look at how many guys call their engines a cummings!mopar2ya said:I know what Im talking about I own the same truck he's trying to mod.
Ive run a 12 cm and 16, both cut my top end power by 2 psi, if you dont believe me talk to James Ray he worked for Cummins for 15 years and was the senior tech on the Dodge Land Speed Record truck a number of years ago, we installed it at his house in TN. So dont tell me what I know, I didnt get my info from some forum or article.
More fuel doesnt mean more power without the boost. The fuel means you can make more boost to use more air. Any 1st year engine guy knows it takes air and fuel to make power. 1300-1400 in the manifold, man your flirting w/ disaster, Cummins says 1280 in the manifold it the shutdown point, perhaps a quick blast to 1400, but if you pull anything you better not play around up there to long.
Again 30 psi minimum, guess what the turbo is doing pushing that hard? Heating the air which raises EGTs, will the turbo do it yes it will, is it efficient not really. There are certainly better compressor wheels you can add for a few hundred dollars.
Finally, more boost doesnt make lower EGTs, what crazy idea is this? Do you own a diesel or just hang out on the forums?
You are running more HP than he is, the 12cm housing gets restrictive around 300 HP which he is not even close too.
This is not a gas engine, get yourself out of that philosophy. More fuel makes more power even without extra boost, however it raises EGT's so thats why you need to run more boost. It works opposite of gas engines.
Of course don't run EGT's that high when pulling! I should have mentioned that part, only empty you can run it that high. He didn't mention anything about pulling though.
He should perhaps upgrade the intercooler to a 94-up version so that high boost doesn't factor in higher EGT's. The stocker in those years is also kinda restrictive. 30 PSI is still fine on that turbo, even the HY35 can boost that much with no problems.
I dont have time to have a circular argument, if you add fuel you will make boost, unless you make the wastegate bypass it. Since he has a Gen 1 truck it has no wastegate hence adding fuel will make boost.
Again, yes the H1C HY35 will make 30 psi, but the efficiency is falling off, I can make a stock R/T turbo run 30 psi, but guess what its not worth a crap there, granted the H1C is much more efficient higher up, but again just because something makes boost, doesnt make it efficient.
Finally since he doesnt need a mega pulling machine, Id just do the free stuff first, like cranking the pump and he may be surprised how quick it spools with fuel. DO the free stuff first then spend money afterwards.
Again, yes the H1C HY35 will make 30 psi, but the efficiency is falling off, I can make a stock R/T turbo run 30 psi, but guess what its not worth a crap there, granted the H1C is much more efficient higher up, but again just because something makes boost, doesnt make it efficient.
Finally since he doesnt need a mega pulling machine, Id just do the free stuff first, like cranking the pump and he may be surprised how quick it spools with fuel. DO the free stuff first then spend money afterwards.
LOL, well he has a wastegated 12cm housing on it so I guess it applies here!mopar2ya said:I dont have time to have a circular argument, if you add fuel you will make boost, unless you make the wastegate bypass it. Since he has a Gen 1 truck it has no wastegate hence adding fuel will make boost.
Again, yes the H1C HY35 will make 30 psi, but the efficiency is falling off, I can make a stock R/T turbo run 30 psi, but guess what its not worth a crap there, granted the H1C is much more efficient higher up, but again just because something makes boost, doesnt make it efficient.
Finally since he doesnt need a mega pulling machine, Id just do the free stuff first, like cranking the pump and he may be surprised how quick it spools with fuel. DO the free stuff first then spend money afterwards.
The HY35 is smaller than the H1C anyway, the H1C is PLENTY good to 30 PSI you can boost it to 35 PSI but thats where it's inefficient. 30 PSI is no problem. Gary Donovan was doing 28 PSI on his stock Garrett T2 turbo and it was still helping even with the stock intercooler....the point is more boost even though it is hot innefficient boost will still make more power. But yes I realize that was a bad example comparing gas engine to diesel but I think you get my point.
He's gonna run what he has, he already has the 12cm housing so it's either that or the stocker. No point in spending $165 for the 16 CM housing which will be slow to spool with only the pump turned up for fuel.
Id give the stock 21 a whirl if for anything comparisions sake. Why have to wastegate something when its not needed.
As far the 28 psi on Donovans car...I had to get a kleenex and wipe the tears from my eyes I laughed so hard. At 28 psi the h.p. gain is so minimal that it will be far offset by the hot air and the engine being brough into detonation sooner. No way is that turbo in the relm of efficient, that went by by by 15 psi. I done responding to your misinformed analogies.
ThePope, sorry for hijacking your thread, if you need any further help, I'll share whot I KNOW.
As far the 28 psi on Donovans car...I had to get a kleenex and wipe the tears from my eyes I laughed so hard. At 28 psi the h.p. gain is so minimal that it will be far offset by the hot air and the engine being brough into detonation sooner. No way is that turbo in the relm of efficient, that went by by by 15 psi. I done responding to your misinformed analogies.
ThePope, sorry for hijacking your thread, if you need any further help, I'll share whot I KNOW.
looked, no "screw" found on the back. Found the upper plate, the easy one. Is the fuel screw like a stud with a hole in the shaft? I have something that looks like a drilled stud with a nut on it and a metal tab coming out the side. What ever it is it was covered as it is not black now. It looks like this tab kept it from turning? Back of the pump means inbetween the pump and the block or behind it facing the fire wall? This had pipes to the injectors sticking out. Do I unscrew this stud looking thing and take off the metal tab? The wording may be different.mopar2ya said:ThePope, sorry for hijacking your thread, if you need any further help, I'll share whot I KNOW.
The back of the pump would be the side where the injector lines hook up. The fuel screw is a bit higher than the lines and a bit in twards the block. If the cap it there you'll see it, if some one removed it you will see a screw with a hex hex on it, it may have a crimp around most of the threads if it hasnt been removed. There is a jam nut that keeps it in place, loosen it and take the screw out and remove crimp.
What your are describing sounds like the fuel screw. The metal tab you describe surrounds the threads and has a small welded tack on it, it this is what you see, remove the crimp and install it all the way.
Let me know how this goes.
What your are describing sounds like the fuel screw. The metal tab you describe surrounds the threads and has a small welded tack on it, it this is what you see, remove the crimp and install it all the way.
Let me know how this goes.
Hate to break it to you but his car went faster with more boost even with it so far out of the efficiency range. He was running race gas at the time because out the heat. Besides, he was only running the stock T2 intercooler so a better IC would have yielded much larger gains (even though with the stock IC the car still went faster with more boost). So you are saying the stock T2 turbo is out of it's efficieny after 15 PSI? Sorry but you are WAY misinformed there pal.mopar2ya said:As far the 28 psi on Donovans car...I had to get a kleenex and wipe the tears from my eyes I laughed so hard. At 28 psi the h.p. gain is so minimal that it will be far offset by the hot air and the engine being brough into detonation sooner. No way is that turbo in the relm of efficient, that went by by by 15 psi. I done responding to your misinformed analogies.
.
You need to understand what effieiency is, without you understanding it, further debate is futile.
You need to understand that I'm just making a point! Even though the turbo is out of it's efficiency range it still makes more power with more boost!
Thats doesnt mean anything, its about efficiency PERIOD!.. Why do you think a hybrid makes about 50 h.p. more than a standard T3 turbo at say 20 psi? Its more efficient. Making boost for the sake of making boost is pointless. Why make 2-3 h.p. psi of hot unefficient boost, when you can make 10+ h.p. per psi?
I personally watched my friends Eclipse run faster at 15 psi than 17-18 psi, time and agin, it was pushing hot air in and causing detonation...
Go to turbonetics website and look at the compressor maks and you will see what efficiency is as related to compressors.
I personally watched my friends Eclipse run faster at 15 psi than 17-18 psi, time and agin, it was pushing hot air in and causing detonation...
Go to turbonetics website and look at the compressor maks and you will see what efficiency is as related to compressors.
Guess what, most of the gain in changing turbo's is the turbine side being uncorked. Go ahead and run a straight super 60 at 25 PSI, then change it to a 50 trim T04E but keep the .63 stock wheel in the turbine and watch it gain absolutely nothing but maybe 5 HP at best from the cooler charge.
''Why make 2-3 h.p. psi of hot unefficient boost, when you can make 10+ h.p. per psi? ''
Well because we are just running what we got on there at the moment. Wouldn't life be grand if we could all just run the perfect turbo all the time and not have to spend any money to get a bigger one. Well some of us don't have a lot of money so we run the stocker for awhile and just for shits and giggles we max it out. But atleast you are finally admitting that more boost even though inefficient makes more power.
''Why make 2-3 h.p. psi of hot unefficient boost, when you can make 10+ h.p. per psi? ''
Well because we are just running what we got on there at the moment. Wouldn't life be grand if we could all just run the perfect turbo all the time and not have to spend any money to get a bigger one. Well some of us don't have a lot of money so we run the stocker for awhile and just for shits and giggles we max it out. But atleast you are finally admitting that more boost even though inefficient makes more power.
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