Options for Compounds with a 38R

V-Ref · Jun 20, 2012

Charles said:
A smaller nozzle makes that situation worse, not better. Power per power a 100% nozzle is going to be making MORE smoke than a 200. Every day, all day.

I agree!

Charles said:
The 100% nozzle will have to hold the injector open much longer than the 200 to inject the same quantity of fuel, so it will have to spray later, making more smoke and more heat to produce the same power.

I agree!

Charles said:
And all of that will happen at an absolute power output far below what the 200% is capable of.

I agree!

Charles said:
To sum up, the 100 will make less maximum power, and will smoke more and run hotter doing it...

I agree!

Charles said:
And without an oxidizer, or the world's smallest set of compounds and a super low rpm peak power point, a 100 is never going to grace 600rwhp on a legitimate dyno in a 7.3L engine.

I kinda agree on the underlined, but not the rest.

Hotrodtractor said:
- but I'd love to be proven wrong.

Here to learn, and hope it happens too.

TARM · Jun 20, 2012

Hotrodtractor said:
I think its optimistic to expect 600hp out of a 100% tip. I don't have a chart handy for a 100%, but there is not much difference between that and an 80% - thats roughly 210-215cc of fuel in a 1000 count test - to achieve 600hp that is pushing nearly 2.8hp/cc.... that is higher than I would say the HEUI injection system is normally capable of and wouldn't expect anyone that could achieve that to be typical results - but I'd love to be proven wrong.

I think I may not have made my position very clear the way I wrote that. I agree with what you are saying and I do not think its in direct conflict with what I was "trying" to communicate in my post.

It was in response to the topic Maddiesel73, V-ref, and Charles were discussing.

What I was trying to say was that I agreed with Charles in that going with the smaller nozzle (100%) was the wrong way to go about it but that I did think you could get there using the volume of fuel that a 100% could flow in 3 ms just in a larger nozzle thus a much shorter PW thus gaining RPMs.

215cc is about what my 200% can do in a ms less i.e. 2ms. Not sure what it could do with some of the well tuned 400% 1.5-1.7ms range?

DocBar · Jun 21, 2012

Will the internal wastegate be good enough for the 38R or will I need to modify the housing? With DI's up pipes, do I still need to crossdrill?

Should I look at intercooling just the 38R or really complicate things by intercooling both?

Should I look at adding 2 BP gauges? I just got in a HPOP, fuel and 0-60 boost gauge and don't mind going a bit CSI and adding a few more. I'm already thinking seriously about adding a driver's side EGT. Thoughts?

TARM · Jun 21, 2012

No you will need a larger gate than the internal on the small secondary turbo. That turbo sees the highest exhaust energy of the two and its the smaller of the two. It going to need the most gate. It needs a relatively large gate in ratio to the turbo size as a fuel only single. WG on the primary are not always needed.

IMO you can not have to much info. I plan to run BP sensor at both points as well as boost.

I have seen a good number of setups only cooling one stage. Other do one stage with a IC and the next with water injection. Then others do IC on both which some times is combo of one air/air and water/air. I think I have read different thoughts on which stage to IC if you only plan to do one. I would think the final stage before it enters the manifold. Reason is the hotter the air is over ambient the more efficient a IC works. Based on this you SHOULD get the coolest final charge by cooling after the final stage.

DocBar · Jun 22, 2012

TARM said:
No you will need a larger gate than the internal on the small secondary turbo. That turbo sees the highest exhaust energy of the two and its the smaller of the two. It going to need the most gate. It needs a relatively large gate in ratio to the turbo size as a fuel only single. WG on the primary are not always needed.

IMO you can not have to much info. I plan to run BP sensor at both points as well as boost.

I have seen a good number of setups only cooling one stage. Other do one stage with a IC and the next with water injection. Then others do IC on both which some times is combo of one air/air and water/air. I think I have read different thoughts on which stage to IC if you only plan to do one. I would think the final stage before it enters the manifold. Reason is the hotter the air is over ambient the more efficient a IC works. Based on this you SHOULD get the coolest final charge by cooling after the final stage.

I am leaning strongly towards wastegating both. I'll have to do some studying to figure out how I want to do the 38R.

I'll be adding my gauges this weekend. I'm looking for a way to add a triple or quad cluster on my dash, directly over the stock instrument cluster, and make it look good.

DocBar · Jun 30, 2012

I've decided to run a Gen3 with my SRP1, so HPO shouldn't be a problem. I'll have the Gen3 paid for next Thursday, so the parts gathering has officially begun.

I'm starting to question going with the 38R and looking into T4 alternatives to allow for a larger range of alternatives. Since injectors are next on my list of parts, I have plenty of time to study on the turbo issues and ask lots of stoopid kweztyuns.

ointlaugh:

Charles · Jul 2, 2012

I wouldn't recommend running the standard Gen3 with even more oil than a stock pump. Run the "small" Gen3.

Otherwise run dual IPR's.

Groomzybanshee · Jul 2, 2012

Why even run a gen3 when you have the srp1

DocBar · Jul 2, 2012

Charles said:
I wouldn't recommend running the standard Gen3 with even more oil than a stock pump. Run the "small" Gen3.

Otherwise run dual IPR's.

I plan on looking into that with great detail and interest. I've been rereading your thread on PSN on this subject. Have you cleaned out your inbox so you can receive PM's or was it just me you're blocking? :slap:

Groomzybanshee said:
Why even run a gen3 when you have the srp1

I think I'm having some minor HPOP issues but can't really tell
and got a deal on a gen3 that I can go back to a stock HPOP if I need to. Plus, I still plan on 400/400 injectors and would rather deal with tuning issues knowing I have enough oil. Besides, I can always pull it back off if I need to. I've got an electric HPOP gauge and plan on making a mech. one also. I'll be called CSIPSD Jr. by the time I'm done with gauges. LOL

DocBar · Jul 4, 2012

Well, this thread might be out the window. If I can close the deal on a GQSSB, I'll go that route. What do you guys think about a 472/96 1.25 to go with it as an atmospheric?

I think I'll listen to some of the more experienced guys on here and rethink the injectors. I like the idea of 400cc's for future growth. Would a smaller nozzle make it easier to tune or just forget it til I learn to tune and go with 3xx/xxx?

MadDiesel73 · Jul 4, 2012

Too small s480 or larger with A 1.39 . With 400/200's.

I'd do a bullseye s483-s488, forced inductions gt88 or Garett gt4718

TARM · Jul 4, 2012

Why are you swapping over from the 38r? I thought you already had it. Did you find a buyer or other use for it?

DocBar · Jul 4, 2012

TARM said:
Why are you swapping over from the 38r? I thought you already had it. Did you find a buyer or other use for it?

I have a guy at work that wants the 38R and my injectors and I might have a deal on the GQSSB that's pretty good.

TARM · Jul 4, 2012

Makes sense. I would not have a single issue running that turbo.

Viking · Jul 5, 2012

what about a gt42 and a 38r?

MadDiesel73 · Jul 5, 2012

Too small need 80+ mm compressor 92+ mm turbine wheel to not be a restriction.. Do it right.

NyCowboy87 · Jul 5, 2012

DocBar said:
Well, this thread might be out the window. If I can close the deal on a GQSSB, I'll go that route. What do you guys think about a 472/96 1.25 to go with it as an atmospheric?

I was under the assumption you were going to run the 472 as the high pressure or secondary charger. That is what it was originally speced for. I would have to agree with the rest of the guys, its too small for the atmosphere charger.

DocBar · Jul 6, 2012

Well, it looks like I'm getting the GQSSB. How would Brian's Precision 101 do for an atmospheric? It's for sale.

http://powerstrokearmy.com/forums/showthread.php?t=19818

MadDiesel73 · Jul 6, 2012

Gonna need bigger sticks for that lol

TARM · Jul 7, 2012

I could be wrong but that that is a big turbo and I do not think a ideal match. Like I said I could be wrong.

How much of your goals for this setup is low rpm response spool up? The GQSSB moves more air than the 38r. I would also think where it lite and how fast it spool up would be a bit less than the 38R. From what I understand not as critical in compounds. I am just thinking in terms of what you goals might be for this setup.

IMO if you go with the GQSSB as it sounds like you are I would give Pius a call and talk to him about good turbo sizes for the atmosphere and what your goals are for it. Man has likely forgotten more about this stuff then most of us will every know in our lifetimes collectively.