Honda D Series Forum banner
1 - 9 of 9 Posts

·
Registered
1996 Civic DX
Joined
·
8 Posts
Discussion Starter · #1 ·
Hi all, I've been a long time lurker here at D-series with a few smaller posts. I currently have a ek sedan with a baby turbo on it (TD04H-15t) and making about 170whp. It doesn't have anything done to the exterior. Still has the stock wheels with the hubcaps on it. My car has been boosted for almost 2 years now and it's time for some more building. I'm doing the whole build in two phases, as it's a better option for my schedule and my bank. In the end, the goal is 400whp. Here is an outline for the process.

Phase 1
First things first, I'm building an extra Z6 block on an engine stand that will eventually be swapped into my car. 75.5mm cylinders, decked, honed etc. P2P0 custom length rods with vitara pistons. OEM head gasket with new OEM pumps. Once the block is done, I'll swap it into my car and turn up the boost on this baby turbo. I also have a rebuilt eg si transmission with an MFactory LSD that's waiting to be mated to the new block once it's done. Also have a stage 4 competition clutch and lightweight flywheel.

For head work, I have a Z6 head with Supertech valve springs, retainers, and valve stems. Also got a Delta 272-2 cam. I decided on not porting and polishing the head, as my machine shop wanted a pretty penny to do the job.

There are a lot of little odds and ends that are going into making the process come together, and that's the most time consuming part. From my previous build, I already have engine management and fuel system taken care of. I won't be getting around to bigger injectors until the second phase (currently running DSM 450's). The goal for this portion is 230whp.

Phase 2
The plan is to start working on the second phase in November. The main objective for the second part is to get the bigger turbo in and also get a fuel system that will support it. Right now I'm thinking of getting a GTX3071R turbo and throwing it on there. I'm afraid it might be a bit laggy but I guess you gotta do what you gotta do for power :wacko: . My hope is that the GTX's dual ceramic ball bearing will cut down on spool time. I considered the GT28RS and it looks like it has a sweet powerband, but it'll max about before I hit 400whp.

For fuel, I'm planning on running 1000cc ID's. The best pump gas I can get here in CA is 91 so I'll have to run that. I would like to stay away from E85 as it's not extremely accessible and I've heard that it'll erode your fuel lines over time.

I'm still theorizing and deciding on parts for this portion. It's coming up so I'm planning on what I'm going to do, but nothing has really been set in motion

Where I'm at right now
I've made a pretty reasonable amount of progress on the first phase. My hope is to have it done by late July so I can enjoy the rest of the summer. The Z6 block already has the internals all put inside. Got the pumps on it with ARP studs poking out the top of the block. I'm waiting on my head gasket to come in the mail so I can put the head on and do the timing. Once that's done, it'll be time to mate the transmission and do the swap.

I just put some Toyo R888R's up front, and they are quite a bit stickier than my old Walmart tires :clap: . Also put an R&D Thermal (3 inch) on the car so now I have a 3 inch exhaust all the way from the turbo to the bumper. The sound is great and I'm really pleased with it. I've left out a lot of information so the post wouldn't be too long. Feel free to ask questions or give me any guidance on anything.
 

·
Registered
1996 Civic DX
Joined
·
8 Posts
Discussion Starter · #4 ·
Well, the bottom end is just about done. Finished adjusting the rocker arms and setting the timing last night. Just need to put the timing cover on and then take the motor off the engine stand. After that, it's time to mate the transmission to the block and pull the old engine out of my car. The plan is to run the car without any boost on OEM injectors and stock ECU in order to break in the motor. After that, we'll swap the DSM 450's back in, and swap the OBD1 ECU back in as well, then get it dyno'd. I'm anticipating the car running really rough in the beginning, as the compression ratio will be lower than the stock ECU is made for. On the same note, the cam and valve train is different. Hopefully the rings will seat without having to put too many miles on it. We'll see...
 

·
Registered
1996 Civic DX
Joined
·
8 Posts
Discussion Starter · #6 ·
The car is off the dyno and running. It made 226whp and 207 ft/lbs of torque on 14lbs of boost. The VTEC wasn't hooked up because I neglected to convert my P06 to be able to support VTEC. The tuner said that he estimates I would get roughly 50 more whp by hooking up VTEC. Here is a picture of my dyno for viewing. It's very peculiar because my turbo reaches full boost much later. I was told that it's possible that the turbo isn't spooling as fast because I'm not running the larger lobes on the cam (non-VTEC). The turbo is still the TD04-15t and before the motor swap I was reaching full boost before 3K rpms. Now it reaches 14lbs of boost at about 4,700rpms. My compression has also dropped to 8.5:1 so that could also explain it. Does that sound right to you guys?
 

Attachments

·
Registered
93 Civic HB SI
Joined
·
1,723 Posts
It's a pretty good bet it's both of those changes together (lower compression and no VTEC), but more likely the compression ratio change more than anything that caused the spool zone to change that much. That turbo isn't that big, and you were getting full spool way before VTEC ever engaged anyways, so comp ratio is most likely the bigger culprit out of the two. Your tuner is right though, once VTEC is hooked up and set a bit lower somewhere around 42-4300 RPM, you should hit full boost at that RPM instead of 4700.

If the bottom end was stock when you were making 170whp, you still had your 9.5ish:1 compression ratio, which is what helped spool low, there is more overall exhaust gas velocity. It's amazing what compression ratio changes can do for turbo spool. If you are going to keep the 8.5:1, your ball bearing GTX you speak of for phase 2 will get you back closer to where you were for spool, but I doubt it will bring you back below 3000 :) but definitely closer.

I'm sure the car will be much more fun to drive with VTEC hardware installed in the ECU, but 225whp and 207lb/ft non-vtec is bitchin! It is very impressive. The fact that power kept steady while in boost up to 6500 is also awesome. What kind of exhaust manifold are you using?
 

·
Registered
1996 Civic DX
Joined
·
8 Posts
Discussion Starter · #9 ·
Thanks guys, I was really happy that it made 227whp without VTEC. The tuner said it'll be about $300 for him to do the ECU conversion and put it back on the dyno with VTEC. I'll be getting around to that in the next month or so. Right now I'm using the Go-Autoworks cast manifold. Nothing special. After reading a lot of threads, I was under the impression that this turbo would max out at about 230ish, so to be able to make a lot more with VTEC would be great. I always get comments and looks about the car being a 4-door with the hubcaps and having a turbo at the same time. It's always fun to drop some jaws hahahaha
 
1 - 9 of 9 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top