96 CX Intake Manifold Swap to 95 DX Manifold

[REDHOTCX]

Hello Everyone,

I have a 96 Civic Cx Hatch. I've been trying to improve both the HP and the MPG. So far this is what i have done to the car. After all of these mods i "feel from the seat of my pants" that car is more responsive, and gas-mileage has gone up from 36mpg (stock) to about 42-43mpg. I have the following modifications done:

-Cheapo-Ebay Short Ram Intake (I couldn't stand the crappy perf. of stock intake)

-Replaced Steelies for VX Wheels w/ 185/70/13tires

-Rear Seat & Mats Delete

I wanted to get you guys' input on replacing the intake manifold from the stock cx manifold to a 95 civic dx manifold. The CX manifold has no plenum, just a crappy manifold that welds all the runners to one opening. The dx manifold has a small plenum (~1 Liter) and has slightly longer runners to the head. I was thinking of getting the manifold sandblasted before installation.

Has anyone done this mod and how did it affect the mpg? I know this should help with high rpm power (i think) but not sure about how it affects mpg.

Thanks Guys

[jmaze]

you will never know till u try.

[imzjustplayin]

Originally Posted by REDHOTCX

Hello Everyone,

I have a 96 Civic Cx Hatch. I've been trying to improve both the HP and the MPG. So far this is what i have done to the car. After all of these mods i "feel from the seat of my pants" that car is more responsive, and gas-mileage has gone up from 36mpg (stock) to about 42-43mpg. I have the following modifications done:

-Cheapo-Ebay Short Ram Intake (I couldn't stand the crappy perf. of stock intake)

-Replaced Steelies for VX Wheels w/ 185/70/13tires

-Rear Seat & Mats Delete

I wanted to get you guys' input on replacing the intake manifold from the stock cx manifold to a 95 civic dx manifold. The CX manifold has no plenum, just a crappy manifold that welds all the runners to one opening. The dx manifold has a small plenum (~1 Liter) and has slightly longer runners to the head. I was thinking of getting the manifold sandblasted before installation.

Has anyone done this mod and how did it affect the mpg? I know this should help with high rpm power (i think) but not sure about how it affects mpg.

Thanks Guys

Sorry but I just have to get this out, this is a terrible idea. Btw, I remember reading in the '96-'00 service manual that the CX transmission in the '96-'00 civics is slightly taller than that in the DX/LX coupes/sedans, can you confirm this for us? At 60mph, how many RPM is your engine spinning at? The transmission final drive in the CX/DX hatchbacks for the '96-'00 is suppose to be something like 3.722, while the rest of the cars with the Y7 engine have the 4.058.. btw, I am fully aware of the difference between the '92-'95 CX/VX and the '96-'00 CX.

Reason I bring up the final drive is that you should already be slightly ahead of the game since you've got an already taller transmission than that of a DX/LX despite sharing the same engine.

[REDHOTCX]

OK Guys,

I'm bringing back this thread from dead.

I never installed the dx manifold but i did one better. I gotta really good deal on a Jackson Racing Supercharger. So I did the install and the following changes were made to the car:

-I ported and polished the Supercharger Inlet and Outlets. I got some headers and an exhaust.

- I put the rear seat and mats back into the car, after sticking some FatMat (knock-off Dynamat)... I know i added maybe an extra 15 pounds to the car, but GOSHDARN it the road noise was terrible.

- I took off the good ole 13" VX rims (185/70/13) and got the new Honda Insight 15" rims (195/70/15). Tall gearing... hehe.

I was going to do a grill block, but the temps might be too high for that to be a good idea. I will post more about the gas mileage loss (hopefully not too much) after i sort out the fueling, and average a few fill ups.

Wish me luck guys