Engine/Transmission (1994 - 1998) Delivery valves & 4,000 rpm GSK question

[Swamp Donkey]

I was good for christmas and got some 191 delivery valves. Will I make any more power with these in my 98 auto pump? Currently has 181's. Read in the archives and there are still varied opinions if DV will increase power.



I also got 60 lb exhaust valve springs. Already have the 3000 rpm GSK in. What I want to know is why am I going to be putting in the 4000 rpm kit when my peak hp & tq is made at a lower RPM? Is the 4000 kit necessary when I can hit 3400 easily? Bottom line is will I go faster?



I am going to get a PDR HX 40 as soon as all the snow melts up here. Don't really need big power in the winter anyways. To cold for me to put on all my christmas bombs... ... ... got a Mag-Hytec transmission pan waiting as well.



My goal for right now is high 13's 1/4 mile. (13. 99) and I would be happy!



Any thoughts?

 

[Todd T]

not an expert but i will give you my opinion. the 191 wont show you much more HP so to speak. they actually could hurt you a bit. the 4k kit is the same thing. if you tune your setup to hit peak torque in the lower rpm's (which i am a strong believer in) then you should never over run it to 3-4 k anyway.



if you are from the high rpm side of the track you would want high timing, and need the 4k kit. i believe i read Joe D showed a small gain when going from 191 back to 181's.



i have the 4k kit because i wanted the stronger springs and figured i can always let off i guess i just wasnt thinking when I bought the 191's i never turn it over 3K and with an auto it wont let me anyway.



did that muddy it up for you

 

[Jim Fulmer]

a small gain when going from 191 back to 181's.



They woke my 180 pump up, yes I got an increase. Dyno'd at 292/680 then added 191's and 370's and 6 Months later dyno'd again at the same place with an 86 hp increase (378/832). 4K's will help mid range fueling as they don't start defueling till later, 3400 RPM's is fine unless it's laying over... . dyno will show that.



Jim

 

[Swamp Donkey]

Interesting on the delivery valves, 2 different answers. I will put em in and see what happens!



As for the 4,000 rpm's unless I manually upshift, I will never see those kinds of RPM's anyways. I am getting good at manually upshifting, been doing it for over a year.



Jim, What you are saying is I may already be defueling at say 3,000... ... ... . and reving to 3,400 where as I can pull hard to 3,400 with the 4,000 gsk.

 

[SlyBones]

From what I have read in these forums is most everyone gets a nice increase in bottom end, and midrange when going to 191 DV's. You should see increased smoke, and reduced turbo lag. Should see improvement in how how the truck responds to initial throttle.



Where the debate forms is in peak HP. Some have had gains and others have not.



Since you got them for christmas, why worry about it. If your installing them to gain a few extra peak HP on the dyno, that may be about it. If you get a lot more, then good. But I would not get my hopes up too high. If your installing them to change the daily drivability habits of your truck, like reducing turbo lag, get out there and stop reading this thing.

 

[John_P]

Swamp Donkey:



My truck gained more "bottom end" by going from the

3K to 4K springs. I have also noticed that my top speed

has increased slightly. This may be due to what Jim pointed

out; that the 4K springs don't "defuel" as soon. If I manually

shift as you describe, I can hit 3850 RPM, however, leaving

the transmission in "Drive" and flooring it, the truck will shift

at about 3200-3400 RPM.



You can look at my signature to see how my 96' is set

up. Hope this has helped you some.



---------

John_P

 

[Jim Fulmer]

This may be due to what Jim pointed



Yep that's what I was talking about, if you put all the stuff in and on the dyno it's not nosing over at the regular shift RPM's then your all good as the truck will not stop pulling at the gear changes, mine begins nosing over slightly at 3000 (top hp rpm) and that is were it shifts, should it no, my pump is less than adequate at rpm... . it's the pumps falt (needs to go to a stand) not the parts fault.



Jim

 

[Todd T]

i dont want to debate you jim, but will point out one thing in your theory. you changed TWO variables and then re dyno'ed. that's a no no if you want to nit pick.



I'll dig up what i read about Joe and see if that will shed some light. as you and I know, Joe would have only changed one variable and retested so i tend to trust his results more.



at least we all agree on not turning it faster



i think this says alot:



I'm running all original parts, including 181 delivery valves, in the fueling section of my original 215 hp pump. Enough for 633. 8 hp.



[Joseph Donnelly]

 

[SlyBones]

Joe has posted on this several times. I believe Joe's test showed no peak HP improvement. I dont believe Joe has ever commented about bottom end and midrange. So depending on the reason you are installing them in the first place, Joe's results may or may not apply. Jim is also not the only one to claim this.

 

[JGK]

180 pump vs 215

I think the issue with the 191 DV's is the pump. They may show more improvement with the 180 pumps found on the '98 autos but very little in the 215s used on the 5spd.



If it were me, and I had a 215 pump (which I do), I'd trade 'em for something that gave me more bang for the buck. But that's just me!



-Jay

 

[Todd T]

i think this is the thread i was talking about. https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=32158&highlight=191

to sum it up he tested 191's in a pump on a stand. it flowed more fuel in the low end but NO difference in the peaks. he then expained his dyno runs were inconclusive due to the numbers shooting high and low over the 181's. now, he took that to the street and complained of smoke pulled the 191's and has been happy since.



now I am speaking out of turn here becuase i have a 180 pump and 191's BUT, i havent taken the proper measures to give myself enough air and have never really power tuned what i have. I am still in the middle of a buildup that probably will never happen. my plans did include a 215 (913) pump swap out anyway. and here lately i was leaning towards a 160 "stupid" pump and cam from piers. this setup was just to "get me by"



SD, you have them, use them. if you have big injectors be prepared for smoke. i would put your stock AFC spring back in and tune the smoke back out. depending on where you plan to take your truck, judge from there.

 

[Jim Fulmer]

Todd, your not going to hurt my feelings on the issue, Joe did say that and Don M reported the same thing and we have talked about it and Don or I neither understand it on my truck but it does seem to not give a topend boost to a 913 pump but it seems to give one to the smaller pumps. While were on the subject of pump instead of buying a 913 pump at a whopping $2200. 00 + why not pull you pump and send it to Piers to make it nasty or sick, they will do what ever you pocket book will allow, turned up, EDM DV's, 13 P&B's, cam, you name it. Remember if you want a sick pump you'll have to furnish a core or send them yours.



Jim

 

[JD4430TECH]

Delivery valves answer.

I put delivery valves in my 1997 Hummin Cummins and I felt a significant horse power increase, but I have a 5- speed trany.

 

[Todd T]

off topic:



Jim i had a deal on a 215 pump for a core. i have a 180 with 253,000 miles on it so i really need a new one. or foot $1000 or so to rebuild it + what ever he does to modify me. the 180 pump cam is not so hot and I would imagine he would recomend a new cam with his custom grind and so on. so i really just need to buy a 160 or 215 pump and have it Piers'fied prolly the same money if you compared the two.



at this point things are all on hold to see if i keep the truck or not. the reason I'm selling is I wanted to start over AGAIN, with a two wheel drive. since i dont need the crew cab anymore. i wanted to go full blown drag setup! four link, short bed the works. but if it dont sell soon I'm gonna start work on it again.



anyone wanna trade a 2wd?