SPS62 vs HTT's QD 64?

[wildmanben]

What gives here? Seems like the posts that I have read on here and other forums makes me believe that the SPS62 spools way faster, duh, and makes more power than my Quick Diesel 64. Is that 62 really capable of that much? I have heard of guys running 70psi through them. I havent been able to find much on this QD64 though.

 

[jwilliams3]

70psi through an s300 variant is a ticking time bomb... I dont care who made it.

 

[Jim Fulmer]

70psi through an s300 variant is a ticking time bomb... I dont care who made it.

Agreed! Last night I hit 63 psi on my 66 and it makes me think about the bomb too. I. I. is sending me a ported housing to control that so I can charge ahead and keep the boost in check. The Silver Bullet has been to 85 psi but there are a few things that need to be re-engineered so it will live there... ..... that is a winter project for I. I.



Back to the topic: Wildman, the only thing I can tell you is the SPS 62 has allot of time and testing under it's belt. I have no idea what HTT's new line is about, but they along with BD have seemed to find out the same ideas that I. I. incorporated 1-2 years ago.



Jim

 

[zstroken]

I wouldn't be scared of the 70 PSI, that would be the upper limit. I would be concerned about the backpressure and the heat generated in the engine since it can't be exhausted correctly. Remember the B1's the originals were not wastegated and people ran those things to 70 PSI. I mean I would probably once a year have it checked or rebuilt. Now a guy with a ported head or a very well breathing motor, might be concerned, cause 70 psi on him will have more shaft speed than 70 psi on somebody that doesn't breath as well.

I just put in a intake air temp gage, the other day. I was a peak of 163, but I was only running about 50 psi through the Silver bullet.

 

[Jetpilot]

I wouldn't run it to that PSI... . I wore out a couple B1's just pushing them to 55-60! The SPS62 is most efficient around 42-44 psi. I know as I did a ton of dyno and pressure testing to see. Big boost does not equal big HP. Heck our old setup could make 610 RWHP @ 44 psi from a turbo slightly smaller than a PS62.



The key is to get the engine to operate efficiently. Setting the boost high will only increase wear on engine components and create heat. Backpressure is a big problem above 50 psi on this turbo as well. The BP increases dramatically over boost as we approach the 50 psi level.



As for the QD vs the SPS62, the QD would be better compared to the SPS64. The SPS62 will spool faster due to the size of the wheels in it over the QD64. The Q64 (in theory) should provide greater topend HP ability and cooling. I have yet to have the opportunity to actually test the QD on a dyno yet, but maybe very soon.



Doug Smith

 

[pwerwagn]

We put a quick diesel 64 on a 01. 5 24V, and a SPS62 on a 00 24V. The QD64 is a slight bit laggier, but nothing a little fuel cant take care of. Having ridden both trucks (although one is 6-speed and one is auto, which makes a big diff), the spool doesnt seem really that much different. And the top end of the 64 seems to make up for it some.



We actually dyno'd the truck with the 64 yesterday. Peaking at 33psi and usually sustaining 30 psi, it made a best of 495hp and 1013 ft lbs. At a max egt of 13xx*. We are going to up the boost some and do bigger injectors and see what happens.

They guy that has it tows a lot with it and loves it.



-Jeff

 

[wildmanben]

so am I ok running 50psi through my 64? or should I back it down a bit and take away some fuel?

 

[zstroken]

The guys that are running 70 psi thru them are doing them in competition. They have to run the 62 for rule reasons. I wouldn't be afraid of running them that hard, but then again if your just dynoing them you have a little more lee way in your turbo choice. Excessive wear is an issue, but once again it is a competition application. If your just running for fun then don't run over 50psi. If your running to win, then run it as hard as you can. Don't by pass the wastegate, probably set it around 45-50, but I am guessing the guys that are running 70 psi in them have enough fuel that the wastegates can't keep up. Do some clean up work on the wastegate, make sure the hole size is as large as possible.

 

[Jetpilot]

Guys running 70 psi are wasting energy doing it. Not only are they wearing their turbos they are costing power. I know that I can keep my boost under control @ over 830 RWHP using the standard wastegate on the SPS line. I see guys do this all the time, run big boost thinking they are making power... . The air charge is so hot that the oxygen density is low compared to an efficient boost amount. Backpressure is insane @ this boost level. Guys need to remember bigger isn't always better and high boost numbers don't equal bigger HP.

 

[zstroken]

I have talked to wildman and I think he is sledpulling. Dynoing and sledpulling are two different things. A good setup on a dyno, may not be the best setup on the track and vice versa. I am not saying dynoing is worthless or less of a competition. I know when I dynoed, I saw about 8 psi or so less and couldn't get the EGT past 1300, same setup when truck pulled puts it at 1750+ on the EGT. What works on a dyno doesn't neccesarily work on the sled pulling track. At 50+ PSI I saw 163 peak reading on my SPA gage. As far as the back pressure not being a good thing, I will agree, but if exceeding the 1:1 ratio gets somebody another 25-50 HP, guess what, guys will do it. I think the people that build the most powerful trucks in the world know something. Talk to scheids about it, at least the last conversation with them on singles I had with them was "wastegate, yea they are nice, but we usally just close them down since yoru wanting to run the charger as hard as you can. " As long as you are less than the 1:1 or even right at it that is a great thing, your not building as much heat and all, but like I said if exceeding that ratio gets another 2 feet going down the track then that is the way to go. I really don't think a engine with 44 psi of boost is going to make more than an engine with 70 psi. Yes the charge is hotter, yes your out of the effeciency range of the charger, but your going make more power not 70/44 more HP, but more. The turbo guys I talked to suggest running the GT42 at 55 PSI or less, guess what, the guys winning on the pulling circuit exceed that. They push 65 psi all day. Is 70 psi alot for a SPS 62? yes would I run mine at that? If my wastegate was set around the 50 psi and I had ported the exhaust housing as much as possible, and still was at 70 psi I would run it like that.

 

[Jetpilot]

Well I guess we have to agree to disagree... ... But I would be happy to take a truck with a PS62 and do dyno runs, one at 45 psi and one with the wastegate clamped shut making in excess of even 60 psi and bet on the outcome.



When we did this the dyno chart improved HP by 5 RWHP going from 44 to 49 but heat was up almost 100*. nce above the 49 mark HP levels actually declined, and the higher we went the greater the HP loss per psi of boost.

 

[zstroken]

I don't want you to clamp it shut, but crank it way up and throw enough fuel at it to out flow the wastegate. Like I mentioned earlier. I have not seen a dyno yet that can load a truck like a sled can. When guys that are sled pulling are tearing up Dana 80s and you see dana 70's run all day on a dyno, that should give a little hint. Dyno's are about getting the engine to accelerate as rapidly as possible at a rapid rate, the pullers typically take 20-25 secs to deliver the load. The big thing in sled pulling is the torque numbers are high. You see a motor actually run at given speed and typically start to drop cause the load is so great. Some even fall off the chargers. I agree with the wastegate and I try to utilize mine. I don't take 100% of what scheid says to be gold. Check out the pullers who are winning in the areas. Ask them if they run a wastegate. Also check what the turbo manufactures suggest as the max effeciency range of the charger and ask what guys are running them at. I would like to see the intake charge temps from say 60 psi and 49 psi or so. From there we can see a trend. I would love to have 70 psi of 100 degree air out of a single. I know the EGT will get higher as you bring up your charge air temp.

 

[wildmanben]

Well thats a lot of useful info to think about. Dan is right, I am using the truck for sledpulling, but do enjoy playing with others on the street. Thats why I chose the 64. Hopefully best for both worlds. I think that I may leave the boost as is and do some more AFC tuning. Should be having a dyno event in the next month or so, so I can mess with the boost and see how the numbers are affected. Thanks for all the info guys!

 

[BILLVO]

I was on the phone for 2 hours the other day with brady at II and his experience with their turbos is that the 62's will flat out outperform and outflow the 64's hands down on cummins engines.

 

[zstroken]

I reread the discussion and about Doug was saying and I was saying, what I am saying is I wouldn't bypass your wastegate. I know people who have done it. Scheid says no, but I believe in the wastegate, it helps the back end breath, but the key is finding the point where elevated air temps at more boost outperform cool air at lesser temps. I did some searching on the web, since it has been 10+ years since I have used P=vnrt(I think that is it) from 100 to 400 degrees at the table I looked at you lose about 35% density. But your jamming in over 60% more air. So I guess where I am at is If your able to deliver enough fuel to overrun the wastegate and build pressures well past the wastegated setting, I wouldn't necessarily back off of the fuel just cause your at some high pressure. I also haven't seen a dyno load a motor right, especially a big single.

 

[KevinH]

i was making 70psi on my sps62 while pulling and on the street. it was night and day difference from 45psi to 70psi. 45psi it felt like it restricted lots of power.

 

[Tomeygun]

i was making 70psi on my sps62 while pulling and on the street. it was night and day difference from 45psi to 70psi. 45psi it felt like it restricted lots of power.

I bet that bad boy sounded sick at the level. A small jet plane maybe??? :-laf

 

[KevinH]

heres the vid

http://s98.photobucket.com/albums/l244/tookatie29/?action=view&current=MOV02267.flv

 

[wildmanben]

sweet, what kind of temps were you running?

 

[KevinH]

it was at 1600* at the 100ft mark, not real sure how much higher it went the gauge only went to 1600