Engine/Transmission (1998.5 - 2002) How much bigger injectors will my turbo hold?

[Clmsnow]

Currently, DTT transmission, 4" exhaust, AFE, HTBG turbo, Comp box and DDII's. With the box on 5x5... on the freeway(flat) I hit 1325* EGT and 39. 6psi boost max. How much more fuel can I throw and be safe?? I am considering Mach 2's or 3's. Like I said, it only gets over 1300* when on kill... at the maximum. I have seen higher when in the hills or steep grade. When towing, I turn the box down regardless so that is not a concern. This HTBG turbo has been great so far, just want some cleaner, more effecient injectors seeing as my fuel mileage dropped 3mpg when adding injectors and thought the Mach series would be cleaner and cooler.

 

[HeavyHauler]

Sounds like you're pretty much at the limit already...



I wouldn't go with anything bigger than a 1. 6 if you have a comp box. That HTBG is pretty much maxed out as it is and you're likely to be at 425 hp with Mach 3s. That's way too much fuel for that turbo.



I've already figured out that HTT doesn't really know the limits of their turbos. I haven't dynoed yet, but I don't figure that I'm putting down much more than 430-440hp with this turbo (maybe less) and my EGTs are way out of my comfort zone. They will rocket pass 1400* and then I let out of it. This is coming from an HTB2 that is supposed to support 450-500HP.



The 1. 6s will give you more power, less smoke, and better mileage than the DDIIs. I ran them for a while with the EZ box and my EGTs never got over 1050/1100* with the stock HX35.

 

[DieselRam30]

Sounds to me like a lot more fuel without more air wouldn't be a good idea at this point as well. I'm going to have to agree with HeavyHauler on this one. If you're towing and already seeing those WOT temps, I wouldn't go anything higher than at the most a Mach 2 if you really watch the temps. But where you're at right now, the 1. 6s would be a good sweet spot.



On the other hand, you get go bigger on the injectors and just leave the Comp in timing-only mode if you're planning on future turbo upgrades anyway.

 

[Jetpilot]

It really depends on how you use your truck and your driving style. You could step all the way up to Mach 4's if you will watch you egts but unless you are going to upgrade your turbo later this would be a waste. Normally guys who haul heavy loads are the folks that need to be aware of their egts the most. If you are set on staying with your current turbo and don't want to worry about egts then go with the Mach 1. 6. If you will keep an eye on things when towing then step up to the Mach 2. 5's.



I have several customers that have purchase Mach 4's and run them with an OEM turbo as long as they don't tow and they watch their egt's. They went this route because they only want to purchase one time and a good turbo is coming in their near future.



Doug

 

[rivercat]

It really depends on how you use your truck and your driving style. You could step all the way up to Mach 4's if you will watch you egts but unless you are going to upgrade your turbo later this would be a waste. Normally guys who haul heavy loads are the folks that need to be aware of their egts the most. If you are set on staying with your current turbo and don't want to worry about egts then go with the Mach 1. 6. If you will keep an eye on things when towing then step up to the Mach 2. 5's.

I have several customers that have purchase Mach 4's and run them with an OEM turbo as long as they don't tow and they watch their egt's. They went this route because they only want to purchase one time and a good turbo is coming in their near future.

Doug

I agree with this, as I was one that ran M4s for 2-3 months on my stock x35 I belive in bigger injectors and smaller boxes. A prime example of this is BoB Wagner's setup of only mach-4's and a dodgezilla 14 hybrid for up-to 401HP he also runs a catcher ecm but that adds little if any hp to the peak of the curve and is more a bottom-end bomb for better spoolup. Bottom line the bigger the sticks the smother and you can always run the box on a lower setting (2x2 2x3) to control heat when needed.

If it was me I would get the mach-2s and run the box low or go for the M4s and ditch the box or untap it an run as EZ. Or better yet do the 4s keep the comp and send the Htbg off the HTT to become a Htb2!

Im running 4s and a PS62 with just a generic timming box called a Diablo power puck and it tows well till the PS spools like mad, Jumps from 10 to 40 so quick the needle is a blur, and slipps the clutch. Then again I think im in the catagorie of people that don't really know the definition of TOWING. As I only pull light loads and stay local most of the time at around 800 feet

 

[mhuggler]

Switching back to the 14cm turbine housing may help, but you'll probably come up short on the charge air side of things. If your like me, you might as well get it over with and upgrade your turbo to a beta x!

 

[Clmsnow]

I can honestly say that I would not waste the money on 1. 6's..... Mach 2's would be the smallest I go. I think that my temps are well within the limits right now... and that is on 5x5. I usually run around town in 2x2. My big question is will the Mach injectors(2, 2. 5 or 3's) run cooler then the DDII's I have in now and how would the mileage change??? And as for towing, I turn the box to level 2 or 1, temps are not a concern when towing. I just thought that since the Mach series injector was better then the DD injectors that I may get better mileage, and seeing as I hear they run cooler, I could throw more fuel at it at the same time. When I put the DDII's in I lost 3 miles per gallon!!!

 

[Clmsnow]

Come on guys... . no ideas on this matter??

 

[mhuggler]

Everything depends on how often you want to keep one eye on the egt's. If it were me, I'd go for the mach 4's and use the adjustability of the box to keep temps in check.

 

[Clmsnow]

I watch my EGT's all the time... or especially when I am in it pretty hard.

 

[Jetpilot]

I can honestly say that I would not waste the money on 1. 6's..... Mach 2's would be the smallest I go. I think that my temps are well within the limits right now... and that is on 5x5. I usually run around town in 2x2. My big question is will the Mach injectors(2, 2. 5 or 3's) run cooler then the DDII's I have in now and how would the mileage change??? And as for towing, I turn the box to level 2 or 1, temps are not a concern when towing. I just thought that since the Mach series injector was better then the DD injectors that I may get better mileage, and seeing as I hear they run cooler, I could throw more fuel at it at the same time. When I put the DDII's in I lost 3 miles per gallon!!!

How heavy are the loads you tow? What altitudes? What type terrain, hilly or flat? Formula 1 injectors are great but there are limits to what your turbo can cool especially under loads. The 1. 6's run very cool and normally guys see a slight improvement over OEM injectors. Personally I like the mach 4's but an HTBG turbo is really too small for these injectors, things will get hot especially when loaded.



Doug

 

[Clmsnow]

I tow aboit 2000lbs in the winter up to 8000ft. Mainly hills... . (Donner Pass/Tahoe). Either way, the hottest I have ever got is 1330* or so, and that was on 5x5. I usually keep in on 2x2... and when towing it would not be any higher then that. I have been told by some vendors on here I could run Mach 3's and be safe. HTT told me they have cusotmers dynoing the HTBG up to 455hp with temps in check. Like I said, when towing I would have the box turned down... more like 375-415hp or so range.

 

[Jetpilot]

The mach 1. 6's are rated at 85 HP and they will run cooler than the DD2's. As you step up in injector size they difference becomes less when comperd to the DD2's. A Mach 2 is a 105 HP injectors compared to a DD2 which is 80HP, etc. Since you are only towing 2K you might get away with a Mach 3 running the HTBG. I do not feel that the HTBG will support towing a 2K load @ 8000 when running 455RWHP. I woiuld say it would do a good job up to around 350-400 which is the range you are now.



Give us a call if I can answer any questions.



Doug

717-557-7060