Momentum

I bought a built JDM D15B VTEC and wanted to put it into my EK and boost it.

Goals: 250-300WHP DD
I want to try autocross this summer, not going to be hardcore just want to try it out. So im looking to build a kit that is more geared towards daily driving, but i dont want the car totally undrivable to autocross. Want a turbo that will spool quickly but still be fast.

This would be my first turbo project, so im asking for help picking a turbo, and an exhaust system that would suffice.

So far i have ordered a mishimoto FMIC, and i have a Greddy type S BOV. Pretty much need to piece together the rest.

Here is the motor build:
Mild built block
JDM D15b VTEC
ACL race bearings speced over
Micropolished JDM d15b crank
Eagle rods
Vitara low comp pistons
ARP rod bolts
Hasting rings
New OEM water pump
New OEM oil pump- ported for better oiling
Head was deassembled and checked over
ARP head bolts and studs
resurfaced fly wheel
Stage 3 6 puck clutch
JDM H22 PRELUDE injectors
MSD 8mm wires
255LPM walbro pump
Dual core aluminum rad
12 inch slim fan
chipped P28 w/ crome
B&M short shifter

I will make this my official turbo project thread, and all questions i have will be posted in here.

Thanks.

TheShodan

iTrader: (14)

The JDM H22 injectors will not be enough for that power. Those barely do anything NA for over 200whp

Momentum

I figured as much, what size should i need?
I have the money to start ordering parts, but i pretty much need to know what turbo im going to be using before i can start buying other things... and i know nothing about turbos!

Any idea of a good turbo to reach my goal?

cleansi

you could pick up a set of dsm 450 rather cheap almost any where. that will support upwards of your power goals.

as for turbos i say if its on ebay or a not a manifacture you ever heard of leave it there
you could pic up a 16g or 18g rather cheap.
you also can pick up a gm 2 bar map cheap on ebay


look in the faq theres alot of interesting reading

most importantly a good tune.... mr vega @ phearable.net has always guided me in the right path im sure you can a pretty on point basemap from them

Sohc52

u mentioned using Eagle rods..

Won't they not fit well in the D15B? It's the 3 stage Vtec one-d right?
I have a local guy also looking to turbo his D.. But we have been contemplating on would the D15B have any problems with eagles or even FJ rods..

Momentum

I will look into the DSM injectors. Thanks.
As for turbo, i can get a t3/t4 ramhorn for really cheap off a friend, will only t3/t4 turbos bolt up to it or will a t3 bolt up?
A good tuner is hard to find in my area...

And it is not the 3 stage vtec motor.

TheShodan

iTrader: (14)

Typically "T3/T4"s T series turbos can come in over 20 different combinations. the housings more or less will be the same as well as the length of the cartridge (GT-R DBB series are typically shorter in size as compared to the T series. The same goes for the BW series.

The question now comes in.. what's your budget? What's the purpose of the car? What's your engine management? Obviously you want 300whp, but how did you want that power to come in? (and don't say "quickest spooling possible"), because you don't know what you're asking for at that point.) Did you want more torque response? Top end power? Something inline with a supercharger?

Here's the difference in height between a standard T3/T04B cartridge and a GT-R series cartridge



Knowing also what your compression ratio is going to be is also going to help determine what turbo to get because different turbos behave differently with different pressure ratios. For example, smaller 540cfm and 640cfm turbos work well in high 20psi ranges to get 300whp, but the compression ratios that they work with are typically very low (for honda standards) of like 7.8-8.8:1. Bigger turbos typically aren't as responsive at the those compression ratios at lower boost, even if you can get 300whp out of it, as they are less responsive.

I know that's a lot to take in, but more information from you will help narrow down your possibilities.

Momentum

Budget: i would like to keep it under 1500-2000 for the rest, but that definately isnt a maximum budget, if i need to i can go higher. I already have the OBD2B->OBD1 harness, P28 ecu chipped w/ crome, Greddy Type S BOV, Mishimoto FMIC, Turbosmart MBC, HKS Turbo Timer, AEM Wideband, Autometer Boost Gauge and Ramhorn manifold. So i guess i still need the turbo, wastegate, charge piping, injectors, downpipe, and oil/water lines. Let me know if im missing anything else.

Ive never had turbo so honestly i dont exactly know where i want my power. I know i dont want something super laggy and i dont want insane amounts of power. Just something FUN to drive reliably as this is my DD... And a setup that wont completely kill my dreams of going to the road course this summer (i know turbo is not ideal for road racing, but im sure its bearable if setup right)

Im just asking for some help on these forums because i want it done properly... I dont want to end up buying a turbo that is not practical for my setup or my daily driving.

How do I find out my compression ratio if i did not build my motor and dont know exactly what pistons it has? All i know is vitara.

jDMJeRk

If your going to autocross this summer, I'd look into something that is ball bearing for longevity purposes.

Since your on a budget you might look into a GT2871 so you could utilize the internal wastegate and save some cash that way. My only concern with that turbocharger would be boost creep (at low psi). You might find that unit to creep in the upper RPM range depending what boost level you decide to run. You could also machine the gate hole of the turbine housing to help relieve the gate choking. The unit is water cooled which will also help with the longevity of the turbocharger especially with how hard you plan on driving it for autocross.

Just my .02 cents... I'm sure most will tell you that you could use a smallercheaper turbocharger to achieve your goals but imo, after you add up the price of a wastegate and a quality turbocharger, I dont see yourself spending any less then $1200 to begin with.

Good luck

TheShodan

iTrader: (14)

I meant budget for a turbocharger. ah.. if you're using the "vitara" setup, you're down to 7.8:1 or so.. yuck. Stick to a smaller turbo. If using a T3 flange, I recommend one of the turbonetics 45 trim 74mm exducers with a smaller F1 turbine wheel. That lower compression ratio you have needs to have a smaller turbocharger to be of any good, really. PM me.

Momentum

Alright i called the guy who built the car and he said the final static compression was 9.5:1 he said the same pistons in a z6 yield a 7.8:1 ratio.

I was also recommended the 2871 by a friend here, or the disco potato. Since the potato was the turbo to have for nissan guys a couple years ago i shouldnt have a problem finding a used one.