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Hope the move goes well Nick. Wish I lived closer, I'd give you a hand and another truck.

It's weird that I can't find any information when searching for the pound-rating of the stock vs HD exhaust valve springs.

The HD valve springs are 60# *over stock*, but it's hard to find the actual spring rates of each one. Then there are the 110# (over stock) springs that are mostly for 24valvers, but I guess some pullers use them on 12 valves. ??

Seems like it wouldn't be too hard to check if you have both laying around. I don't.

I still have stock valve springs. That should be next on my list... then I can do a valve adjustment too, which I'm sure has never been done to my truck. :doh:
you have a 4k spring with no valve springs?? you are lucky not to mess up alot!
 

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you have a 4k spring with no valve springs?? you are lucky not to mess up alot!
Oh yeah? Well, why is that then? Tell me what I'm gonna mess up and how it'll all happen. :hehe:
Do you think a 4k GSK just revs your truck up to 4000RPM all by itself?
 

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you have a 4k spring with no valve springs?? you are lucky not to mess up alot!
the stock gsk starts defueling the motor at 2200rpms whether you have the plate removed or not. the 4k spring allows you to run more fuel in the higher rpm range so the truck wont fall on its face. it wont hurt nothing by running a 4k. hell the motor wont turn 4k even with the spring in unless you have some pump mods done cause i dont think the turbo nor the stock p-pump will fuel it that high. you can prob get 32-3400 out of it.

12veg we need a timing section. i am trying to learn about that. if the timing is advance, that will cause better response and lower egts correct? what is stock timing usually at? where is a good spot to put the timing if you are only running a stock turbo and no plate? thanks again man, keep up the great work
 

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the stock gsk starts defueling the motor at 2200rpms whether you have the plate removed or not. the 4k spring allows you to run more fuel in the higher rpm range so the truck wont fall on its face. it wont hurt nothing by running a 4k. hell the motor wont turn 4k even with the spring in unless you have some pump mods done cause i dont think the turbo nor the stock p-pump will fuel it that high. you can prob get 32-3400 out of it.
Well, I can get the revs as high as I want, (I once saw it as high as 3500RPM when my mechanic drove it, but I'd never go over 3200). It was smooth as silk at 3500, but the noisy part was me yelling "SHIFT YOU A$$HOLE!" :hehe:

What Doidge was saying is that you can do a 3k GSK if you don't plan on valve springs, but I'd never do a 3k - it's a waste of time. It starts defueling earlier than 3k and with advanced timing (mine's at 17º) and injectors, a 12-valve is good til 3200 at least. I need those last 400RPMs.

I just know that I won't push the revs to the point where I will risk exhaust valve float. You can free-rev it to 4k all day long and get no valve float, since it's the boost + high revs that cause the exh valves to hang open.

I plan on doing valve springs ASAP, but it's not risky at all in the meantime.
My point (in response to Doidge's warning) was that I doubt he knows what all is at risk if he's issuing warnings not to install a 4k kit w/o valve springs or your engine will blow up.

12veg we need a timing section. i am trying to learn about that. if the timing is advance, that will cause better response and lower egts correct? what is stock timing usually at? where is a good spot to put the timing if you are only running a stock turbo and no plate? thanks again man, keep up the great work
The stock timing varies, from around 11.5-12.5 depending on year. The earlier 94/95 160/175HP engines were timed lower and the later ones higher.
Mine was at 12º or 12.5º.. can't remember - don't care.

If you advance the timing, it shifts the powerband UP in RPM's. Going from stock timing to 17º, I lost a LOT of low-end power (below 1700RPM) and gained a LOT of upper end power (2500-3200RPM). My spool suffered from loss of low-end.. but hopefully the 024's that are in the mail from Mathews8PT will help (he's now running my old 191's - we just traded).

But I didn't notice any change in EGT's. My low-end smoke was more after timing. Could've been a tuning issue, which I've resolved as good as possible with the stock DV's. When I get the 024's in, I'm sure I'll have to tune the AFC s'more to get it dialed.

You need to match the fueling to your turbo. And you need to advance your timing based on what injectors you have and what you're planning to do with the truck.

With stock injectors, 15º is probably a good number for DD'ing and you're not going to gain anything by putting it past that with stock injectors.
With my 5x12's, 17-18º is good. Even 19-20º would be good, but I'm on the stock head bolts/gasket.

If you have studs and 5x16's and you're looking to make like 600-700HP, you may be better off going with 20º or higher timing.
 

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thanks man. i am stock injectors and tubro with no plate. i plan on atleast going to an s300. i would like to be in the 450-500hp range. i am trying to find out what i need to get there. i know i will be doing valve springs, head studs, oring head, new turbo. do you think i will need new injectors? like 90hp or 5x12's i think?

what is the delivery valve? im sorry i am still pretty new to all this.
 

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thanks man. i am stock injectors and tubro with no plate. i plan on atleast going to an s300. i would like to be in the 450-500hp range. i am trying to find out what i need to get there. i know i will be doing valve springs, head studs, oring head, new turbo. do you think i will need new injectors? like 90hp or 5x12's i think?

what is the delivery valve? im sorry i am still pretty new to all this.
Depending on which S300 (there are lots of sizes) you choose, plus 5x12's (yes 90HP) you should have no problem hitting 450HP.

500HP on a 62mm will take some extra effort, like delivery valves and maxing the pump's fuel rack travel (by modding AFC and installing a 2095 rack plug).

The delivery valves do what the name suggests. Google P7100 DV photos. They deliver fuel (out the top of the injection pump) to the injectors. They are lifted (opened) by the plungers, which sit inside a barrel (like the DV sits in a cylindrical seat) and the plungers are lifted by the pump cam.

But 500HP is easy to hit with 5x14's (140HP) and a 64mm turbo. You should be closer to 550HP with that kind of combo.

I would say you'd be fine with just studs and no o-rings. Lots of people think they need them when they don't. I guess if you think you'll be pushing over 600HP someday soon, then maybe it's worth it.

I hear it's not that expensive to get the head Cn'C'd (like $200-300) but I just don't think it's necessary unless you're going big compounds. Studs & a quality HG (maybe thicker than stock) should hold up to a huge single or small-mid compounds.

I even think just doing studs and leaving the head/gasket alone is what I would do.
 

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well this is a dd and it sees quite a bit of idle time, thats the reason why i want to stay in 450-500 range. makes it super efficient and really reliable, but yet has plenty of power for towing. i will be doing alot of towing also if that makes a diff in what size turbo. i know twins are really good for power/towing combo cause your small turbo will spool super fast and get your moving then the bigger 2nd turbo comes into effect. if i run a big single, i need one that i can get lit up by like 1600rpms tops. i like to get to turbo spooling fast so i dont have to be so high in the rpms to make gobs of tq. thanks for all the help so far algae
 

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Well, I can get the revs as high as I want, (I once saw it as high as 3500RPM when my mechanic drove it, but I'd never go over 3200). It was smooth as silk at 3500, but the noisy part was me yelling "SHIFT YOU A$$HOLE!" :hehe:

What Doidge was saying is that you can do a 3k GSK if you don't plan on valve springs, but I'd never do a 3k - it's a waste of time. It starts defueling earlier than 3k and with advanced timing (mine's at 17º) and injectors, a 12-valve is good til 3200 at least. I need those last 400RPMs.

I just know that I won't push the revs to the point where I will risk exhaust valve float. You can free-rev it to 4k all day long and get no valve float, since it's the boost + high revs that cause the exh valves to hang open.

I plan on doing valve springs ASAP, but it's not risky at all in the meantime.
My point (in response to Doidge's warning) was that I doubt he knows what all is at risk if he's issuing warnings not to install a 4k kit w/o valve springs or your engine will blow up.

i know exactly what will happen if you dont do valve springs. usually piston to valve contact it pretty serious. that just my .02 but i was only warning you because not everyone knows that and or understandes it. i didnt know you only reved up to 3200
 

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i know exactly what will happen if you dont do valve springs. usually piston to valve contact it pretty serious. that just my .02 but i was only warning you because not everyone knows that and or understandes it. i didnt know you only reved up to 3200
You might want to go back and add a [/QUOTE] to the end of my post, that way your post is separate from mine.

Everybody who has spent more than a week perousing this forum has heard the valve float warnings about 50 times. Just because you have a 4k GSK doesn't mean you rev it to 4k.

Do you understand why people run the 4k over the 3k?
There is a big difference in throttle response throughout, from idle all the way up. It fuels much more responsively throughout.

Once you've tried a 4k, you'd never want a 3k. It's too mild and mushy.

The fact that you can even safely go 200RPM over the redline (on stock valve springs) on the tach is kind of amazing. Everyone knows that they should never over-rev their sports car. Most of the older sports cars didn't have rev limiters. If you miss a gear, you can blow the engine. You just don't miss a gear and floor it. But even if you did, it wouldn't build boost (on a Cummins) so it wouldn't float a valve if you're not in gear and boosting hard.
 

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i read the turbo section and im still kinda lost. i got the sizes, but i want to make 450ish hp. would it be better to go twins or single? i dont tow, but i will be towing once i get the power up. i dont care to really smoke at all. i like where my egt is now. under wot it's about 1220 flat ground and 1240 pulling a hill without towing anything. i would like the turbo to be lit pretty low in the rpm range say 1500-1600 rpms. i dont want to have to do alot of motor work. i will do valve springs and head studs, but would i need to do o-rings? or new injectors? thanks

oh, i will be bumping up the timing to about 16-16.5* and installing a 4k gsk
 

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i read the turbo section and im still kinda lost. i got the sizes, but i want to make 450ish hp. would it be better to go twins or single? i dont tow, but i will be towing once i get the power up. i dont care to really smoke at all. i like where my egt is now. under wot it's about 1220 flat ground and 1240 pulling a hill without towing anything. i would like the turbo to be lit pretty low in the rpm range say 1500-1600 rpms. i dont want to have to do alot of motor work. i will do valve springs and head studs, but would i need to do o-rings? or new injectors? thanks

oh, i will be bumping up the timing to about 16-16.5* and installing a 4k gsk

you will want some 5x.012/ 370 injectors with the correct spray pattern, and depending on altitude a 62mm turbo. you could do twins with your stocker for a broader power/range and lower EGT. Price would only be about $600 more, but labor is a pain.
 

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i read the turbo section and im still kinda lost. i got the sizes, but i want to make 450ish hp. would it be better to go twins or single? i dont tow, but i will be towing once i get the power up. i dont care to really smoke at all. i like where my egt is now. under wot it's about 1220 flat ground and 1240 pulling a hill without towing anything. i would like the turbo to be lit pretty low in the rpm range say 1500-1600 rpms. i dont want to have to do alot of motor work. i will do valve springs and head studs, but would i need to do o-rings? or new injectors? thanks

oh, i will be bumping up the timing to about 16-16.5* and installing a 4k gsk
--- edit ---
Oooopsie, sorry JKidd, I didn't see your post
Well at least we said pretty much the same thing...

And one more thing, (to rtc1184) stay away from marine 370's.
That's why JKidd said "370's... with the correct spray pattern".

--- off edit ---


450-ish, you will be good with a 62mm turbo and 5x.012" injectors.
You shouldn't *need* headstuds (let alone o-rings) for 450HP.
For that #, you should only need about 45PSI of boost which is just below where studs start becoming a worthwhile preventative measure.

Everything else (your timing & GSK plans) sounds good too.

The part about smoke is up to you and your patience for tuning.
If any of us can get it dialed in, you could too. Or if you know a 12v guru in your area could tune it, may as well bring it to them for AFC tuning to make sure it's perfect.
 

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you will want some 5x.012/ 370 injectors with the correct spray pattern, and depending on altitude a 62mm turbo. you could do twins with your stocker for a broader power/range and lower EGT. Price would only be about $600 more, but labor is a pain.
yes cause i do want to keep my egt's under 1300 while towing if at all possible. alt will range from 400ft to about 1500ft in northern arkansas at work.

--- edit ---
Oooopsie, sorry JKidd, I didn't see your post
Well at least we said pretty much the same thing...

And one more thing, (to rtc1184) stay away from marine 370's.
That's why JKidd said "370's... with the correct spray pattern".

--- off edit ---


450-ish, you will be good with a 62mm turbo and 5x.012" injectors.
You shouldn't *need* headstuds (let alone o-rings) for 450HP.
For that #, you should only need about 45PSI of boost which is just below where studs start becoming a worthwhile preventative measure.

Everything else (your timing & GSK plans) sounds good too.

The part about smoke is up to you and your patience for tuning.
If any of us can get it dialed in, you could too. Or if you know a 12v guru in your area could tune it, may as well bring it to them for AFC tuning to make sure it's perfect.
ill prob do studs and springs just in case. i want as much reliability as possible. ill have a shop stick the injectors, gsk, studs in and while its there i will have them do the full rack mod on the afc and tune it to the best of their ability which is probably better than mine.
 

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Well I don't think that you'll have a problem keeping your EGT's below 1300º while towing... but that's all in how you drive. If you use 3rd (OD Off) on steep climbs, it will keep your EGT's down (higher revs = lower EGT's).

If you have compounds, you'll still have to do that probably. I don't think they will be able to keep EGT's down any better in 4th (at low revs) than a single. You still have to drive it with that in mind whether you have compounds or not.

But if you're not trying to gun it at 70+MPH, in 4th, towing up steep grades, you probably won't hit 1300º. You could do a 3-position TC L/U switch that allows forced unlock in 4th. That will heat the transmission temp higher while towing up climbs, but you could unlock the TC in 4th and that'd raise the revs a bit, enough so you don't have to downshift constantly up the hills.

A lot depends on your gearing & tire size. What do you have?
 

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Well I don't think that you'll have a problem keeping your EGT's below 1300º while towing... but that's all in how you drive. If you use 3rd (OD Off) on steep climbs, it will keep your EGT's down (higher revs = lower EGT's).

If you have compounds, you'll still have to do that probably. I don't think they will be able to keep EGT's down any better in 4th (at low revs) than a single. You still have to drive it with that in mind whether you have compounds or not.

But if you're not trying to gun it at 70+MPH, in 4th, towing up steep grades, you probably won't hit 1300º. You could do a 3-position TC L/U switch that allows forced unlock in 4th. That will heat the transmission temp higher while towing up climbs, but you could unlock the TC in 4th and that'd raise the revs a bit, enough so you don't have to downshift constantly up the hills.

A lot depends on your gearing & tire size. What do you have?
right now its stock rearend and gears on stock tires. it will be stock gears on 38's or 4.10's on 38's havent decided. when im not towing i do like to run it pretty hard from time to time when messing with someone on the insterstate.
i noticed now if i barely get on the throttle and let the tc lock on its own around 50-51mph my egts will climb from 800ish to about 1200 until it spools then they drop until i get into higher speeds like 90-95mph then they will climb back to 1240*. right now the way it sits, the higest egt i will get going uphill with it to the floor is 1240*. before i put the boost elbow closed it would reach 1400-1450* under wot. so now i have the boost elbow closed and producing 34psi on the stock hx35 holset turbo and it brought my egt's down to 1240*. also i have the stock down pipe and 3" straight pipe exhaust which here pretty quickly i will be going to a 4" downpipe and 4" straight to 5" bull hauler stacks. that should help some as well and then the timing should help some also correct?
 

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right now its stock rearend and gears on stock tires. it will be stock gears on 38's or 4.10's on 38's havent decided. when im not towing i do like to run it pretty hard from time to time when messing with someone on the insterstate.
i noticed now if i barely get on the throttle and let the tc lock on its own around 50-51mph my egts will climb from 800ish to about 1200 until it spools then they drop until i get into higher speeds like 90-95mph then they will climb back to 1240*. right now the way it sits, the higest egt i will get going uphill with it to the floor is 1240*. before i put the boost elbow closed it would reach 1400-1450* under wot. so now i have the boost elbow closed and producing 34psi on the stock hx35 holset turbo and it brought my egt's down to 1240*. also i have the stock down pipe and 3" straight pipe exhaust which here pretty quickly i will be going to a 4" downpipe and 4" straight to 5" bull hauler stacks. that should help some as well and then the timing should help some also correct?
Well, being that this thread is a sticky now, (for the purposes of helping beginners) it may be better for you to start another thread with these questions. That'll help the mods keep it concise and to the point without having to delete anyone's posts. ;) Know'm sayin?

But so far, all your posts have been something a beginner should read because it's common questions we've all had when crossing the various stages of modding. Your exhaust should help EGT's & spooling a little bit, but the timing won't really help EGT's.

What you said about lugging at 52MPH when it's at really low revs, that's exactly why I'm saying that people shouldn't use 4th/OD on steep climbs below, say, 65MPH (depending on gearing/tires). It's best to use higher gears when climbing if you're worried about EGT's.

But if you want to be able to floor it whenever while towing 15k pounds (up hills or on flat) and also have 450HP (which requires bigger injectors, pump work etc...) you may want to pop a bigger turbo under your stock one and do budget compounds. That'll hit your goal w/ no probs and also maybe run a bit cooler than a 62mm single could. I dunno cuz I've never tried it.

Or, since EGT's are what you're worried about... there's always water/methanol. :) That's hecka cheaper than even cheap compounds.

And if you're wondering what most people use as their big turbo in a set of cheap compounds, it's usually a HT3B or S471, 474 or 475 or something similar. It's not too smart to go much bigger if the stock turbo is what's pushing it.
 

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i would start a new thread but this one is open and i have seen so many threads about making power, but its for people wanting to smoke. i dont. i want low egts and as little smoke as possible. thanks for all your help. ill prob give jkidd a call and discuss all this with him and see what im looking at.
 

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Discussion Starter #58
In the process of adding FAQ section.

Feel free to suggest q's to add to it, as well as links to their appropriate articles if necessary.

Craig: How about that AFC tuning article that you were gonna write up and post in the tech section??? :homer2:
 

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Discussion Starter #60
I have a crazy question, what size bolts are used to secure a starter on on a 1997 2500? I tried to remove mine yesterday and i could not find SAE or metric.
No idea, you'd be better off asking this in the forum.
 
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