I currently have an Hx-40 on my 98.5 and its kind of a turd until its spooled. This truck is a tow/work vehicle that hits the local pulls from time to time. I was thinking that it is a 60/65/16 due to it performing the way it does. How would a 62/71/13 or a silver 62 work on this truck? It's got 3.55 gears 110hp stix and a few boxes With a billet goerend. What turbo would I be happy with other than twins.

 

64/71/13 is the sh@# for a single

 

How is you're HX-40 configured? There are lots of different set-ups on both the turbine and compressor. 14cm housing works best for spool-up but you get more egt's. The easiest way to tell which compressor impeller you have is to count the blades on impellers 6 is the higher flow, but usually comes with a larger A/R housing. You can mix and match up to get it to work right. If you want you're icing and cake, go with the garrett 3788R stage 3. fast spoolin and tons of air. Its rated to 550 hp. HX-40's are good for 400 to 450rwhp area. I've had a few Hx-40 (five now). I've never killed one yet. Which wastegate actuvator is on the turbo?

 

Super B Special would be a great match to that truck. It is going to spool a little quicker than the HX40, but it is way more efficient and has a much stronger shaft in it as well.

 

i dont think so mike.. i have a 14 on my turbo and it will only hit 1300 if im from a dead stop other then that it will maybe touch 1200.. bluechrome i think a 62/71/14 would work well for a truck thats ment to be a towrig/puller (everyonce in awhile)

 

How much advance/timing you running on the pump. You running deliver valves, what position is you AFC, all in or all out? A mechanical pumps are hard to put down an exact turbo size, as there are lots of variables that effects egt's. I drive a VP truck, so its easier to pick a turbo to work based on injector size. A 16cm exhaust housing will help cool off the egt's vs. a 14cm, but you're spool-ups will slow down. If you got the money for a new turbo the 62/71 is a good all a round driver turbo. Twins will fix the problem of egt's but they cause more maintaince with you're driveline and cause more boost leaks (more boost). I still prefer the garrett 3788R over the holset and it will almost push the same amount of air as a small towing twin set but thats more $$$ and HX-40's are cheap cheap. Put a BTH-3B under the HX-40, tons of air, cheap to build but the intial spool-up is abit sluggish (depending on how you're set-up on for fueling)

 

My truck is a 24v. I had a 64/71/13 on my common rail. It was nice but I think it won't spool as well on the 24v isb truck. My temps top out around 13-1400 With the torque Enhancer on. Im thinkin a 62 of some sort Just not sure on what size to spool well and and keep the egts down while towing. I Dont know if a 65 wheel will be to small. I think I might need a 71 or 74 to keep my egts and Drive pressures down. I have a fairly big set of twins on my common rail currently but that more money then what I want to put into the 98.5. Pulus I don't thk the HG will take very much

 

no pump timing, no different delivery valves, the afc isnt gutted it isnt all in or all out

 

You guys are running two different rides. If you have twins and you want fast spoolin, but max HP isn't top of you're list, then go smaller on the secondary turbo sizing for twins. If you tow, go bigger on the secondary turbine housing. Whats your set-up the wastegate? Try to go lower on the wastegate pressure on the secondary so you can lite the primary harder and sooner.. As for the guy running no timing, no AFC, I really can't say on what to do. Anybody else run that combo?

 

Not trying to single you out, just trying to clear up a very common misconception about wastegates on twins. You do NOT want to open the wastegate up earlier to drive the primary harder. When you open the wastegate the primary has to work that much harder to make up for the loss drive pressure. This can and does blow up the primary charger. Keep the wastegate closed as long as you can to gain a true compounding affect.

Here is a quote from our Turbo engineer JWT

"As for the wastegate opening more this will increase negative delta pressure (exhaust pressure higher than compressor) you should try closing in the wastegate or shutting it off; when you open the wastegate the lower turbo speeds up so the overall pressure may not drop. You may have to reduce fuel slightly until you O-ring the heads.

During testing we controlled any negative Delta P by closing in the wastegate, the results were at 60lbs the pressures were even; and at 70lbs the exhaust was 5lbs higher this is very good.

You must remember the purpose of the wastegate is to control boost pressure not to lower exhaust pressure."

 

You must remember the purpose of the wastegate is to control boost pressure not to lower exhaust pressure."[/QUOTE]

 

[/QUOTE]

You cant affect one without the other........correct.

 

You cant affect one without the other........correct.[/quote]

To a certain extent yes. But when you open the wastegate in a twin setup, the primary charger has to work much harder to keep up and they tend to blow up. As soon as the wastegate opens there is a big spike in drive pressure. That tends to make the big turbo go "POP"

 

Well I have put in real seat time. I find that the turbo(s) lite faster with the wastegate opening at around 20 to 26 psi. I can't really see how leaving it closed makes the primary to light better and lowering drive pressure. A some point the secondary will choke and will become a bottle neck on exhaust. Thats why you put in a bypass valve (wastegate) and open it up. This goes for both of my 40/BTH3b and 3782R/BTH3B set-up. As for a BD set-up, I never ran one, Pat you can mail me one, I'll luv to try it out.
Think about this you're using exhaust that been pushed thru one turbine and going into another one. How can that be the most efficent way to lite the primary up. The trick is balance them both turbo out so you can have both low drive pressure and egt's. I've ran my twins with them I have ran the wastegate's closed and wide open and at various different opening pressure. Different wastegate sizes and downtube configurations. Maybe my truck is different from everyone elses out there and I'm more than welcome the chance to beat on someelse's truck with twin set-up.

 

Mike I agree with you. Any tuning I have done with a 40/3b, 20ish seems like the magic number.