rb25det with gt3071 - how much lag?

[makeuw3t]

Hey guys,

i've searched a few times and couldnt find anything specific to the rb25det AND the gt3071 (or similar) in regards to lag or when full boost kicks in. so, if any of you out there is, or has run a gt3071 or similar turbo, can you tell me when you hit full boost and what psi you were set at? or if you can say if there is noticable lag or can you compare it to a stock rb25 turbo please?

reason i ask is im looking to get a garrett t3/t4 57 trim, and im stuck at being scared the t3/t4 wont make it to my rwhp goal of about 375. on the other hand, im sure the gt3071 can get me there, but im scared there'll be lag or full boost at say 15psi wont kick in till 4500rpm. i know ill need injectors and ems (which are budgeted down the line), but my question is for the turbo only. im leaning on getting the t3/t4. i have a feeling the word "lag" and "375rwhp+" go hand in hand.

anyways, any help, info, suggestions, or comments are greatly appreciated

thanks,

michael

ps. the car will be used for daily instant gratifications, a little track and/or autox, and maybe seldom drift, but probably no drag.

[Beancooker]

Here is the compressor map for the GT3071R. http://www.turbobygarrett.com/turbobyga ... T3071R.htm

Here is the formula for figuring LBS of air, etc... http://www.turbobygarrett.com/turbobyga ... ch103.html

[Zacho2]

gt3076 .82 ar on an rb25. conservative timing, I spool 10 psi by 3800-3900. a 3071r would be reasonably better with a smaller housing.

Honestly I think these gt30 turbos work awesome on the rb25. It definitely is no stock turbo, but I hated how the stock turbo spooled lightning quick. Hard to stay out of boost for gas mileage in town and annoying bov all the time.

I've got a quick video I will upload to youtube to show ya.

[Zacho2]

done uploaded it quick

http://www.youtube.com/watch?v=EwkJC7fuC6c

Watch the boost gauge on the right. I don't put my foot down until it almost comes out of vacuum. It isn't bad at all really. Not even wide open either, I was datalogging the run.

[GSDKinked]

Hey guys,

i've searched a few times and couldnt find anything specific to the rb25det AND the gt3071 (or similar) in regards to lag or when full boost kicks in. so, if any of you out there is, or has run a gt3071 or similar turbo, can you tell me when you hit full boost and what psi you were set at? or if you can say if there is noticable lag or can you compare it to a stock rb25 turbo please?

reason i ask is im looking to get a garrett t3/t4 57 trim, and im stuck at being scared the t3/t4 wont make it to my rwhp goal of about 375. on the other hand, im sure the gt3071 can get me there, but im scared there'll be lag or full boost at say 15psi wont kick in till 4500rpm. i know ill need injectors and ems (which are budgeted down the line), but my question is for the turbo only. im leaning on getting the t3/t4. i have a feeling the word "lag" and "375rwhp+" go hand in hand.

anyways, any help, info, suggestions, or comments are greatly appreciated

thanks,

michael

ps. the car will be used for daily instant gratifications, a little track and/or autox, and maybe seldom drift, but probably no drag.

If you're staying in the 30R family then the lag issue really comes down to your tuning. Look for steve shadows via google and zilvia or Cody Ace they know their s***. And will help advise you on how to properly get the spool times you're looking for via tuning.

[makeuw3t]

Hey guys,

thanks for the info, zacho, thanks for the vid. ill prob pass on the t3t4 and save up for the gt30XX. anyone got one for sale!?

[meet07]

I have a hx35...suppose to be around the same spool characteristics. Output as high as 500

[GSDKinked]

Hey guys,

thanks for the info, zacho, thanks for the vid. ill prob pass on the t3t4 and save up for the gt30XX. anyone got one for sale!?

honestly, I would pick up an AGP turbo. i am currently loving my delta 48. It maybe journal bearing but the spool with the .63 housing is awesome. I will be upgrading to a .75 divided V band housing soon after I get this setup tuned. Flow is 48 lbs/min i believe. This places it between the 3071 and 3076 in terms of power. AGP says it can hit 480 with this housing (.63) but they don't know about my set up because it's never been on an RB before.