I am in the process of putting a turbo kit together for my LS Vtec. It will be on a stock B18B1 bottom end with ARP rod bolts and a stock rebuilt B16 with 3 angle valve job and B16 cams. I may put GSR cams in it when I turbo because I can get some cheap from a friend, not sure on that yet though. My power goal for the stock motor is 280-300whp, I want to make boost around 3500-4000rpms so I can keep some decent around town gas mileage but dont want super lag. So far to me a basic TO4E .57 .63 AR looks to be a pretty good choice. Any thoughts? Plans for 400whp on a built block in the future.

 

sc61

 

Oh not sure if it makes a difference but I want to retain AC and PS on this one. I have a Cast log manifold that is AC PS compatible. How will the SC61 with 69 trim wheel and .63 AR respond to my lower hp goals on the stock block?

 

I made 271 on a sc61 str8 LS spool was great, sc61 also gives you room to make more power later down the road.

 

SC61 is on the list of possible turbos then, looks like it will be good for what I want.

 

Ouch. I betcha there are a number of people who'd out accelerate you with half the turbo that a SC61 would produce, especially on a straight LS motor with 271whp. That's been done on GT3251s and even 50 trim T3/T4s.

That's just too large a turbo for such an engine.

Example. Straight LS w/ 10psi on a GT3251 Journal bearing system. It was just getting started. Maximum pressure was reached by 3200rpms.



And that was only 50lbs/min compared to a 61lbs/min SC61 with no powerband whatsoever

For LS VTEC, you only need about 52lbs/min-58lbs/min like a GT3255 or Equivalent.
You DO NOT NEED an SC61 for anything usable unless going for over 450whp on pump gas.

 

Ok so the To4e I am looking at or your custom To4b is a better choice for me then? I have boosted plenty of cars but this is my first personal boosted Honda and I am getting into turbo info and spec s lot more now.

 

Well, in some cases, the universal fitment ones work fine, but there are those that want a little extra umph for their dollar for a particular use. So it depends upon the use, power goal, and your budget. Staring at specifications all day is great, but it doesn't help with actual application until you research a few completed setups that are similar to your goals in mind.

There is no best here. Just simply "best for you"

The GT3251B is not a full custom, just a semi-custom configuration using Garrett parts. But there are others that will work as well.

 

Just dont buy to small, you will regret it in the long run when you build your motor. I went from a 271whp stock ls to a built ls vtec on 29 psi making 630whp. You will always want more power.

 

Better to be smaller in an efficient range then go too big and regret the lack of responsiveness later. What he has to do is state what he's trying to with the car. Too many people get a turbo just TOOO BIG for what effectively works, then get pissed when a smaller turbocharged car with better torqueband gets them out of the hole. By the time the bigger turbo finally gets his act together, the other car is already gone..

And the "Larger turbo gets better traction" argument just doesn't add up.

 

^ how much power will the gt3251b max out at?

 

You never, ever want to use a turbocharger at its maximum. About 425whp. 90% of the people have found that whatever turbocharger they use, after 460whp, there's no point in keeping on the street; you're just fighting to control the car more than actually having any fun in it... regardless of drag radial or traction bar, or any of that.

More than that, you'll want at least 53lbs/min or higher, but over 61-66lbs/min, be prepared for it to be a bit "laggy".

 

I stated what I was wanting from the turbo in the OP. Capable of 400whp but still be good for 250-300whp with a boost threshold of about 3500-4000rpms so I can have some traction and get good around town off boost MPG's. Keeping the AC and PS is a must for me and I have a decent cast mani that will work, I know cast is not the best but for my app it will work nicely. TheShodan any advice you can give is great, as know your **** for sure and I am with you on what you are saying. To small and spin tires to big and no fun.

 

If 400whp is youre max then get the t3/t4oe 50 trim. You will have a more usuable powerband and could come close to youre max goal of 400whp but you will be at the limits of that turbo...You could go with the 57 or 60 trim of that turbo and get to 400whp easier but loose some resposivness. i myself have the 60trim

the 50 trim seems the best bet. Shodan knows the most with turbo selection but like he states its really whats best for you. Everyone is different

However you will most likely want more power in the future, so you may want to keep that in mind

 

This is true, though I'd go 57 trim, GT3255B Journal Bearing (which will fit better with a cast manifold), or if you're a little more brave, the EFR 6758, GT3071R, (GTX) or TR3071R. Precision Camp (5557, or 5857) Either way, I'd stay about 50lbs/min - 56lbs/min maximum for a build like this.

 

To4E 57 trim with .63 AR seems to what will be one of the best suited for me, pretty standard Honda turbo. If I decide I want more than 400whp which is a lot for a street Civic, then I will be changing the whole setup and ditching the AC and PS for more room. I will check out the other turbos mentioned. I am getting my line up of turbos and narrowing it down to what I feel will be best. Oh I want to stick with a 5 bolt exhaust as well on this set up.

 

this is a SC34 in precision, aka 3431e, the reason i bring this up is cost, turbo daves has them for $539 and the 5 bolt housing doesn't cost you extra like it does in garrett

 

Eeek. Unless its a Precision that cost just went up for that silly downpipe flange.

 

do you have any idea why garrett does this? makes it a bitch for the cast manifold crew

 

Wow after looking at the dyno sheet that car has no usable power until the very top end, not a good setup. Crappy power curve.

 

Because it was originally inverted as a type of Top mount manifold. Blame FORD for this, not Garrett. It was made to sit high, upside down for the Mustang SVO from the late 80s early 90s.

The original "cast manifolds" from Rev-hard and DRAG in the late 90s which used the 5 bolt ford style turbine housings to help with crooking the turbo for the downpipe to allow A/C. That's changed now with a lot of the custom one now made. This is why these cast manifolds, will one day fade away (sorry to say).

 

Well I can always wield on a 4 bolt flang onto the down pipe I was looking at getting or just get a 4 bolt down pipe.

I will check that turbo out. Turbo Daves?? More info please.

A good friend of mine was suggesting a 54 trim instead of a 57 trim for my power goals. Thoughts?

 

You must not know how to read that. The power curve was fantastic. From 3000-5800rpms, it was just steady, steady torque. At over 222 ft/lbs of torque for over 4000rpms, that is fantastic. That setup was something many had been trying to get for a long time. Usable power was EVERYWHERE..

 

Yeah sorry Im learning but in no way noob. After looking at my dyno sheets (NA) and looking at the curve I see my statement was wrong. To correct myself that does have a very nice power curve. Tq starts to drop off above 5k but it still wants to make more HP in the top end. My NA tq curve is not that smooth not that it is anything special. The GT3251 would be a good turbo also then for me?

 

No offense taken. Yes, that would be a good one. Or, the GT3255B, due to the VTEC head.