Ok guys, I don't post much, and read a bunch, and just want to start off by saying THANKS for all the great info. It is wonderful to have all this real-world experience in one place.

On to my story: I have to get some work done on my nv4500, so I went ahead and ordered a SB 13 con ofe. This stuff should go in next week. I went to order guages, got to looking at the other stuff I knew I wanted to get one day, and ended up getting the following: pyro and boost guages, 4kgsk w/o hd valve springs for now, #10 plate, 370 injectors. I got the stuff from PDR. I asked about the AFC spring kit, but the guy recommended against it at this point. I also ordered the snap-on sp500 timing kit to advance my timing. I already have a scotty II installed (hole is not cut yet), and have my cat and resonator cut out/replaced with a resonator from a 24V.

I will install the guages first, but my available time to install the remaining add-ons will be scattered. What should be my order of progression on the following?

4kgsk
#10
370
adv. timing

Will I definitely need to cut the hole for the scotty II, will I definitely need to convert my exhaust to a true 4"? The salesman said my next upgrade would be a turbo to the sound of $1600, and I just don't have that right now. What will be my apprx. power output with what I have? Thanks.

Waylan

 

Your gonna need a new turbo for sure. Those 370's and #10 are gonna make for a toasty ride. Definately cut the hole for the scotty.

 

To me, the gauge install took the most time, but I fabricated new clips to fit on the A-pillar cover and worried about tapping the manifold. Once you're past the gauges, you're home free.

You could easily do all those listed in an afternoon if you want. If not then I would suggest that you do the 4K GSK and the #10 plate together. You've got to get into the pump to do both anyway. Mark the stock plate location for furture references before you take it out (lightly scribe a line). If you keep the plate back a little you can keep temps controllable until you can do the exhaust and timing. Don't over rev with the 4K kit and no HD valve springs. You can save some time now and mark top-dead-center when you're cranking the engine over to do the springs and be ready for the next jobs. I'd say then do the timing next with or without the injectors. Not hard to do both in less than 2 hours. You'll have to lossen the injector line on #1 for timing and may as well do them all for the injectors (I don't like to bend the lines too much, but others have).

There may be a minor advantage to working in steps. If something doesn't work right, you'll know which part is screwed up. If you do all at the same time and it doesn't work, then you've got more to sort out. Keep reading and posting questions. There's guys here with even better ideas and experience.

 

Thanks for the input guys.

BigBlue, what turbo upgrade would you do if on a tight budget? Could I just change out the housing, or am I pretty much stuck with an expensive full replacement?

I forgot to add in my original post that I do not tow anything heavy.

Waylan

 

Waylan:

I know that you asked Blue but I'll give my 2 cents worth. I'd give Paul at High Tech Turbo a call. He's a great guy to deal with. They have a hybrid based on your current 35 that works well for a lot of guys and is reasonably priced. If you add delivery valves then it would really get toasty but if you stick with injectors and adjust the #10 you'll be okay. Any questions PM me.

Paul

 

For turbos, you could get away with adding a 16 cm exhaust housing but a HX35/40 Hybrid would be a better solution and be under $1000........As blue mentioned, you will NOT be able to get away with a HX35 and 4000 gsk/#10/370's without sending egt's into orbit!......You already have 181 dv's in your 215 pump which will easily support 370's so I would suggest not adding 370's to the 215 pump until you have a turbo to flow the extra air required to support that much fuel......

Yes, definately get 4" exhaust - you will need it to keep egt's down and it compliments the Scotty II nicely........

As for the installation order, here is my .02 :

1) gauges - you will be installing and adjusting the rest of your mods blind without them.

2) #10, 4000gsk and timing.......I would suggest 17-18*......Paul already mentioned doing those together because you are getting into the AFC module for both anyway.......I don't know why you wouldn't do the AFC spring at the same time - the stock 215 spring really is too stiff for good low boost fueling......

3) At this point you are going to need 4" exhaust to help keep egt's down if you are messing with plate positioning......

4) 370's/turbo......I list those together because you really won't be able to run the 370's safely without a turbo upgrade........

Get all that done and you should easily exceed 400 hp..........by how much would depend on the turbo...........

 

i run the 370s with a #100 plate and hx35 with 14cm wastegated housing. it does get hot but it will run. i would suggest against the afc kit, you will get plenty of fuel with 370s and the housing slid forward. mine is in the 450 rwhp range right now and is a excellent daily driver. i cannot just hold the peddel down without getting very hot but it will hit 100 with out any major issues. but i don't feel bad if the gauge stays pegged for a couple of seconds. i tow up to 30k gross and have never had egt problems, if it gets hot i back out a bit. and i would suggest a 5" exhaust, if you do what you are planing to do, the power will become very addictive and twins won't be far behind. i said i would be happy at 350, then again at 400, and now again at 450. yea i am weak, the twins are built laying up in the shop, just waiting on the dualdisk/6 speed install to be done[saturday].

 

Thanks so much for the info guys. I talked to Paul at High Tech, and he recommended the HTB turbo, saying I could easily upgrade it in steps as I needed to. I figure I will get my current mods installed, including timing and exhaust, see where my temps are, and go from there to see which turbo he recommends.

I do have another question regarding the heavy duty valve springs: Do I just need the 60 lb springs on the exhaust valves or on intake valves as well? Also, when changing the springs, do you have to make sure that piston is at TDC to keep the valve(s) from falling into the cylinder? Thanks again. This site is the best.

Waylan

 

The HTB turbo is definately the way to go if you can swing it........If you can upgrade the turbo in stages to meet your requirements then that is perfect!..........

General rule of thumb for 60 lb exhaust springs (this does not apply to intake valves): If you run an exhaust brake and/or a 4000 GSK you will need the 60 lb springs........you don't need them with a 3000 GSK.......some guys do run the 4000 GSK without the 60 lb springs but it is not recomended........if you have an exhaust brake, they are required........

I'm not certain if setting a piston at TDC will hold the valve high enough to make the spring swap easy........The only time I have seen springs swapped on a CTD was with compressed air.

 

So, a 5" is necessary with twins??? Can it be done with a 4"??

 

every turbo i have looked at that is ht3b or bigger has had a 5" exhaust outlet. you could neck it down to fit a 4" but it would just seem wrong. but i have heard of it being done.

 

Maybe I misinterpreted CTD Nut's comment "General rule of thumb for 60 lb exhaust springs (this does not apply to intake valves)", but from what I've read and understand is the 60# springs should be used for intake and exhaust if you're using the 4K GSK. The reason being is there's a very real possibility that the valves (any or all of them) will float and possibly make contact with the piston(s) if you're revving the engine much beyond 3K RPMs (i.e., like 3400 and above) and not using 60# valve springs. The OEM springs, from what I've been told in an email from Piers, are a considerably lower spring rate due to the original design criteria of the 12v engine having a redline of 3K. The 24v engines have 60# springs in all locations which is one reason they can and do rev higher without danger of valve float. Piers also went on to say there's no data he's seen that indicates there are any durability or reliability problems in using 60# springs for intake and exhaust in a 12v engine.

Again, I may have misinterpreted CTD Nut's comment, and if so, I apologize as I don't mean to flame anyone here. Just hoping to clear up what I know about the subject.

Steve

 

No, you got it right Rocky........I got it wrong.......I was trying to type too fast and say too many things at once.......I should pay more attention to what I say! ..........You are correct, you must replace both intake and exhaust springs for a 4000 GSK however, for exhaust brake installations you can just install the heavier exhaust springs only........

Sorry for the mix up guys.......and thanks for pointing that out!

 

Ok guys, I'm back. This past Saturday, 2/26/05, I installed my guages. Nothing on my truck has been tampered with so far as the injection pump goes. Anyway, everything went fine and my temps were normal from what I've read. If I stayed into my truck to say 95 mph (top speed), I was still barely in the yellow. Stock, my boost went to 23.......almost 24.

So, Sunday morning, I installed my #10 plate, in the stock position, afc slid all the way forward, no adjustment to the starwheel. Very nice wow factor.......I was driving a pig before the plate swap. My boost now climbs to 36-37, and I can peg my egt's, but it takes work.......it doesn't just jump there. I can get to say 80 mph before it gets to the red.......then I can let out slowly and find the sweet spot where the egt's stay in the yellow but I'm still gaining speed. Anyway, I'm fine with all that.

Anyway, my question regards what I have left.......4kgsk and 370 injectors. I can tell that the engine quits pulling hard because of the defueling........so should I just install the 4kgsk and then wait until I can afford a turbo to put in the 370's? Or is there a housing swap that I can do to be able to run both? It seems as though I have seen someone running 370's and a #10 and 3kgsk........is it possible to do this?

Another question regarding turbos........would you guys that have run HTT turbos recommend the HTB or HTB2? In other words, with what I have to fuel with, will be able to overfuel for the HTB and end up needing the HTB2? Once I add my gsk and 370's, the only thing I would consider is adding delivery valves and nothing more. I just want to get the right turbo the first time and be done.

One last question: I believe I am hearing my turbo bark if I chop the throttle sometimes during the overlap of pressing in the clutch........will this harm my stock turbo? If it does harm, could it disintegrate or what are possible outcomes? Thanks.

 

Walexa

My set up is similar to yours; I waited for the turbo before putting in the injectors. I did try the DV’s before the injectors and had a major EGT problem; I could peg a 1500 degree gauge in 2-3 seconds. I guarantee it was getting a lot hotter than that. I would install the 4kgsk as soon as you can you will love that. I went with the htb2 and am very happy with the performance of this set up. I did take the DV’s out and have left them out (PM me if decide you want DV’s I still have them). At wot I can get to about 1400-1450 degrees, but that takes a while and that’s as hot as it gets. Spool up is better than it was stock. I didn’t have any problem with my stock turbo barking but my trucks an auto, the htb2 will surge sometimes if you get the conditions just right, but it’s easy to drive around.