Honda D Series Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
201 Posts
Discussion Starter #1
I'm getting near the point of putting my car together, and keep having different things said to me and different ideas... (keep in mind that this car hasn't even been started yet)

I want this car to run 12.0 or better and be able to cruise on the weekends. I'm not making a drag car, but I want to be able to drag it...if that makes sense.

Just a little precursor to my situation...my bottom end is 75.5 CP w/ FJT rods GE block guard. Top end is Crower stg 2 cam, springs, retainers, ferrea valves.

I currently have a Full-Race Ramhorn, 44mm WG, 3" DP, and a SC5031 50-trim .48hot .60cold. Should I do a topmount with a 4" DP or keep the F-R?

I don't know if my turbo is sized correctly for what I'm trying to do. My guess is that I need about 350whp. Am I going to be boosting this turbo to the moon just to make power?

I have two sets of injectors 680cc and 1000cc Precisions. Hondata s300. Walbro 255. XS FPR. I don't know which injectors to use. Should I go 91, 91+meth, E85, 101?

I have a Precision 350hp intercooler. Is that enough?

What size IC piping do I need?
 

·
Well?
Joined
·
10,814 Posts
i think you will be fine with the FR piece no need for a Top mount. That turbo is plenty for what your trying to do. If you run E85 you'll need the 1000cc's but i think the 680's are fine if you run pump. Your IC should be fine but you may need to upgrade depending on how many PSI you will be running. 2 1/2 piping should be fine also
 

·
Registered
Joined
·
201 Posts
Discussion Starter #3
I don't really see the need for 3" piping. I see people do it though. To me, it makes sense that it really doesn't need to be any bigger than the throttle body size. People run 4" downpipes though. What's up with that?
 

·
Registered
Honda
Joined
·
2,692 Posts
2.5" IC piping. no need to run 3' with your setup. Alls your going to do is lose boost pressure through the IC if you make the piping too large. You want it to flow freely with as little backpressure as possible, but you dont want it to lose velocity from using bigger piping.

As far as downpipe......as big as you can get it. if you can fit a 4" DP in there, DO IT!! You will make your setup so much more efficent as you size up the exhaust. 3" will be fine, but the bigger the better. Turbos create backpressure on the motor if the exhaust doesnt flow through them easily enough, especially those with a small turbine like youy running, but again, you will be just fine. That 3" DP should suffice.

Your turbo should also be good enough for 12's. I think it will get a little choked up on the high end compared to mid range, again because of the smaller turbine side, but that really depends on how high you plan to rev.

go with the 680 cc injectors if you are going to be using regualr 91 or 93 pump gas. I dont know if you will meet you goal of 350whp on pump gas without a really kick ass spot on the money tune, but best of luck. If you know a tuner that can tune e85, i would run with that. It is about the equivalent of using 105 octane. I would actually buy a moates 2-timer chip and have a gasoline tune and an e85 tune to switch between in case you get stuck somewhere without e85. If you use e85, you will need the 1000cc due to the requirement of ~ 30-40% more fuel under boost.

As far as your intercooler goes, yes that should suffice. Hopefully its no more than 2.5" thick.......they are less efficent because of the thickness, all of the air molecules dont always make it through the entirity of the core, causing them to just sort of migrate halfway through, thus not doing as good of a job cooling your charge air. i would definately go NO MORE than 3" thick for the IC.
 
1 - 4 of 4 Posts
Top