Engine/Transmission (1998.5 - 2002) Advice on turbo choice

[sparks57]

Ok, so I'm trying to figure out what kind of turbo to get, I know it can be complicated, so I'm trying to be as specific as possible here:



Here is what I'm looking at for a setup, it may or may not end up exactly like this:



Fueling:

Drag Comp

Possibly a caTCHER ECU

Mach 3's or 4's



Air:

4" Exhaust

Mild head porting

Other misc. porting

ATS manifold

PDR Towing Cam

Mega Cannon Stage II Intake





This truck is an auto, DTT 89% or 91% (probably 91)... depends on what they recommend. The truck is mainly a daily driver, but I am a lead foot and would like to drag race, on occasion. The truck will tow a light 25' camper trailer every once in a while, and a small car hauler trailer with a race car on it... nothing seriouse. I'm looking for balance, and as little lag as possible, that's why I'm opting for the cam and porting... but I also don't want thermonuclear EGT's.



Ok, I'll shut up now... opinions?



I was looking at possibly one of the Kwik Spool B1's...



Oh yeah, and maybe also keep in mind that it will possibly be the smaller charger on a set of twins some day... but that is in no way a priority.

 

[Rattlin_Ram]

Can't make a recomendation, but might help to know the Alt. your at in Idaho.

 

[sparks57]

Very good point... I believe I'm around 6200ft.



Turbos are such a difficult subject... new ones are always comming out, brand loyalty get's in the way, I just don't want to learn by trial and error, it gets REALLY expensive!



Also, maybe an htb2?

 

[AWray]

From everything I have read on this site and a couple others, the HTB2 from High Tech Turbo seems to be the latest and greatest single. The HX40's and B series are all great, but come with tradeoffs. Although lots of people have had good luck with these turbos.



CB Parker, you are right on the brand loyalty issue. Whomever you talk to has the best turbo. I would advise that you call several different vendors and collect their recommendations then make your own decision.

 

[snowracer69]

CB,



altitude + tight t/c + lots of fuel = the worst spool you've ever imagined.



I'm at 4000-5000 feet depending on the time of the year, and when it's hot out the thing is nearly undrivable w/o smoke. Go out with your pickup, and from a dead stop, smash the go-pedal. Denis and I both count "one-one-thousand, two-one-thousand, three-one-tho" before our turbos lite and we're off. There is absolutely NO stop-light racing w/ rice because of this! We HAVE to build boost in order to race! It is IMPOSSIBLE to race a 6. 0 or Dmax from a dead stop... . there is no catching up from 3 lengths back when you finally lite, even with 150 RWHP advantages.



Now, saying that, I don't recommend the 91% t/c (I know you didn't ask, but it's too tight for your altitude). Our 89's run good, and when you have it DTT'd, go full billet throughout and put in a lockup switch for racing... you'll gain everything back.



For a turbo, we started w/ KSB-1-2's and now run B-1-2's... . much better top end than the KS housing, not much of a loss in spool ("... . three" instead of "three-one-tho"), but it still can't handle our EGT's (especially mine w/ the Drag Comp... the word "hot" that is written on it is an understatement).



What we will probably end up with is a set of twins w/ a very small turbo on top (12 cm exhaust probably) and a fairly big one on bottom. Externally wastegated off the manifold, but dumping everything into the big turbo to lite it faster. This is also $3000 away along w/ headwork and other stuff. We probably could use our B1's for the top turbo, but I don't think I will... . probably end up with a hybrid of some sort.



As for that being said, if you end up wanting a B1, throw me a PM and I'll set you up... have a fairly good connection w/ Ken.



Josh - BOMBing at altitude where few try to drive every day... spent three days at the Oregon coast last weekend though, and had to leave the comp off to keep the rears from spinning at every shift... you guys down low don't have a clue what it's like to be w/o air every day!

 

[sparks57]

Yep, I know exactly what you're talking about. Thanks for the recommendations! I'm still in the planning stages of BOMBing this truck (waiting for warranty to expire ) so I'm open to any and all comments/advice. My only experience is with first gens, so I'm eager to learn!



Ok, so it's basically between a set of twins with a small top charger, or an HTB2.



But, my major issue is this: I want EGT control (I don't think it's fun to peg pyros, I had my fair share of that with my first gen), and as much bottom end as possible.



Do you think twins would serve the purpose better? With a small top charger, they would spool relatively quick, and the bottom charger would keep EGT's at bay.



I may be getting my old turbo back, and it may do well as a top charger on a set of twins... it's an H1C that was honed out for a the hx-40 pinwheel, it has updated bearings and it's balanced and ported... very similair to a PDR-35, I believe. Would that with a 12cm housing be a good charger to base a twin setup on? Or would it be too small and cause a flat spot in the power band?



But then again, that HTB2 is supposed to spool pretty fast...



Man, I'm confusing myself...



Please give me more input!

 

[sparks57]

Oh, and keep in mind that this is my first auto, and I'm not very well versed on autos...



With that in mind, what does a lockup switch do?

 

[snowracer69]

it gives you manual control of when the t/c locks. Mainly used in racing applications for reduced 1/4 times. When the transmission shifts into second, flip the switch to ground out a wire on the PCM (I think... . maybe the ECM... it's the one on the firewall for god sakes!) and to make the t/c lock when it normally wouldn't. I believe Rhonda found it to be worth 0. 3 in the 1/4. BUT, you definitely need billet shafts to do this.



Forgot to add, when the switch is in the locked position, you are getting locked-to-locked shifts... . not healthy on most parts in the transmission.

 

[rubberneck]

I would have to agree with snowracer on this one, go with a set of twins. You are running a lot of fuel with what you are describing, and even with the full size B1, you can get some pretty high temps. Not to mention, with the larger single,your towing performance goes down which will be compounded by the altitude. I dont live up there, but do tow up there once in a while, and it sucks. Thank god I'm at sea level for the day to day stuff. LOL I think the PDR towing twins would make you pretty happy. they are built similar to what snowracer is talking about.

 

[sparks57]

I'm definately starting to lean in that direction... thanks guys!

 

[snowracer69]

just keep saving and do it right the first time.



transmission first, full billet EVERYTHING!

Headwork, all porting/polishing, studs, o-ring or fire

twins of your choice.



Claim from someone (don't remember who) was that with mine or Denis exact setup now, by adding twins we would be sitting at 550, up from the ~450/460 mark... just cause that extra fuel is being used, not lost.

 

[sparks57]

Oh yeah man, I'm getting the transmission done before I spend a DIME on anything else. The stock auto is, by no means, a tough unit. I'm not even going to run an EZ... just straight to billet!!!



Besides, I'm not going to mess around, I'm going straight to the big stuff... it's cheaper that way, less money spent on temporary BOMBs.



So do you think 35/ht3b twins would work better than 40/ht3b twins at this altitude? It's just that PDR calls the 35 twins as "towing twins" and the 40 twins as "street/strip" twins... so I'm wondering if I can get a lot of power through the 35 twins... .



Thanks!

 

[snowracer69]

yes, the 35 w/ a small housing should work well at altitude, if you stay at or below probably 500-550 RWHP. Just make sure it's externally wastegated off the manifold w/ that dumping into the big one... .



ok, I don't have any experience w/ twins, but I've talked to a LOT of people who have them and build them... this is what I have learned from them.

 

[sparks57]

500-550 is right where I want to be...



Ok, so which size of EDM would be required for that type of twins? Mach 4's? Maybe 5's? I'd probably have to talk to Don.



And did you know if that honed out h1c would make a good top charger? I'm pretty sure it's almost identicle to the PDR 35... but someone please correct me if I'm wrong. It's just an H1C that was honed out for the hx-40 sized impeller, zero balanced, and ported. I'm thinking the 14cm housing would probably work best... but I'll probably have to mess around to get it tuned right.



Hopefully the small top charger, and [maybe a] caTCHER ecm will make up for the auto and 24v's lack of bottom end torque... . :-laf



I don't want to sacrifice any more bottom end than I absolutely have to.