RTE117

hi, I'm new to this forum, I love Hondas and DSM's and I was wondering something about all these boosted B series Honda's around here.. Why do so many of them get T3/T4's when they don't plan on touching the internals? Majority of the boosted Honda's around my area never go above 8 psi yet they use these turbo's that are easily capable of 400+ whp .. I was thinking why not use a 14B or 16G 7CM? they are extremely efficient @ that psi, plus they're spool-up is much faster and they are much cheaper. Is it because many of the turbo manifolds are designed for the T3/T4 turbo? jw.. thanks

b18bturbo

Its simple most of the manifold on the market all utilize t3 flanged turbos. Also if you properly size a t3/t4 to your liking you can make some good number way more than i would with 16g at the same boost level The only ones that dont are the japanese manufactures becuz they utilize fast sppool up and good quality kits.


[Modified by b18bturbo, 5:11 PM 2/6/2003]

falcongsr

i thik part of it is that teh honda motor flows a lot of air at high rpm compared to a lower revving engine. to get a good match between the compressor wheel and the airflow in lbs/min of the engine at high rpm, you end up running a big ole turbo.

RyanAutry

Isn't is all about air flow instead of manifold pressure.

Why not get a turbo that out flows a small turbo with less manifold pressure?

Of course you don't want to over do it. You don't want to do too big.

falcongsr

corky bell talks about this briefly with the porsche large single turbo. its really laggy on the street but hey it put out 400hp back in the day. nissan ran lil turbos on the 300zx so the throttle response was amazing but it choked up top or if you modded it. so when u test drove the car u were like WOAH its so fast cant wait to open her up then u buy it and take it home and beat on it and it starves up top cause the turbos were so small to give it that snappy feel and hard pull in low/midrange.

dmotoguy

another thing is that honda's cant get traction as well as an AWD dsm, so if there is a little bit more lag it helps you get traction earlier instead of spinning the tires, another reason im gonna get a bigger turbo

DIRep972

iTrader: (1)

We dont run big turbo's for 8psi. They are properly sized turbos. a bigger turbo flows more volume at the same pressure and will make more power at the same boost level then a smaller turbo. The DSM guys just think they are big because they aren't quite as advanced as us.

Smashback

yeah, we run half of a "small" big turbo

the other half is still just a t3!

RTE117

more volume @ at equal psi yes, but look at compressor maps.. the 16G is about the same @ low psi. 8 psi isn't the best efficiency for a T4 compressor housing, but with the comment about DSM's not being as advanced.. well I'll leave that alone.. I've rode in 12 sec DSM's that took only $500 to get there.. whether we/they are as advanced or not.. they're much easier to extract power from.

DIRep972

iTrader: (1)

im just playing about them not being as advanced us. I always find DSM owners telling me my turbo's too big. but i consider it small. or properly sized.

I went from 110whp stock to 230whp w/ a T3/T04e @ 8psi. This is on a 1.8L non vtec engine only revving to 7k so its a fair comparison w/ the DSM motor. I gained 15hp per psi, you cannot tell me that turbo is not in its efficiency. how many 16g guys make 230whp @ 8psi? I think the DSM guys are just scared of lag. where as honda guys don't really care, cause we dont have turbo in the first place.

b16ahybrid

because my t3t4 is matched to my engine a lot better then my old t3 was.It spools almost as fast,and provides a lot more power then the t3 ever did plus i have way more top end power (the t3 would drop off above 6k rpm).
You get the best of both worlds quick spool (t3 housing) and high flow (t4).Some of the engines can make use of the larger turbo because they have more rpm to play with then other engines of same size or even larger. I wouldn't recomend going with a t3t4 on a honda engine that only revs to 6k rpm, but on one that revs to 8,500rpm it's a different story.
btw my old turbo was a t3 .48 exhaust .42 compressor
my new turbo is a t3t40E .63 ar .57 trim.
@7psi i'm making as much if not more power with the t3t4 then @10psi with the t3.

HXMan

You hit it right on the head! My friend upgraded to a small team rip ported 16g...he complains about it getting full spool at like 3500 rpms..stock 14b hit full spool at 2500 I think.