Hf To Si

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chad123

Member
OK i have 1988 honda crx hf..I found a 89 crx si head and ecu for cheap and i was wondering if i swaped my hf head and ecu with si head and ecu will i get any more horse power out of my car???
 

D See 2

Senior Member
definitely. try to find the intake manifold as well. you will DEFINITELY notice a gain. your hf has an 8 valve head and is fueled for better gas economy. the si head is a 16 valve and will make a difference.
 

biglee414

Senior Member
no you dont have to convert to multi point fuel injection, an hf is already multi point, a dx is dual point fi
 

D See 2

Senior Member
Originally posted by biglee414@Apr 1 2003, 10:31 PM
no you dont have to convert to multi point fuel injection, an hf is already multi point, a dx is dual point fi

werd
 

Mech

Banned
D15B6 (hf, your motor)
.
Displacement (cc): 1493
Power (bhp@rpm): 62@4500
Torque (ft/lbs@rpm): 83@3000
Compression Ratio: 9.1:1
Bore (mm): 75
Stroke (mm): 84.5
Cam Design: sohc
VTEC?: no
OBD: 0
Year(s) Produced: 1988-1989
In the following car(s): Honda Civic HF / CRX HF

With manifold, ecu, and head..... vwalaaa!!:
D16A6 (si.... your upgrade)
.
Displacement (cc): 1590
Power (bhp@rpm): 108@6000
Torque (ft/lbs@rpm): 100@5000
Compression Ratio: 9.1:1
Bore (mm): 75
Stroke (mm): 90
Cam Design: sohc
VTEC?: no
OBD: 0
Year(s) Produced: 1988-1991
In the following car(s): Honda Civic Si/ CRX Si

All in all.... Very worth it. :spin:
 

Mech

Banned
yeah, but I'm not sure if the si has shorter gears or not. Look into getting the si tranny if it has shorter gears. But yeah, it's a very nice gain.
 

chad123

Member
HF is alot lighter than the si soo thats gonna be a PLUS when i swap correct??
 

Mech

Banned
The Si tranny is a little different but I don't know if it's really worth spending your money. I think the HF is lighter because of the motor size mainly, and maybe a couple of interior things. Once you add all this stuff it should be about equall to the DX. The Si has the sunroof and power everything so it will wieght more.
 

Jeef

NO MA'AM
Moderator
VIP
Yes but you will be slower with it.
 

saturn_boy96

88 C1V1C 53D4N DR1V3R
your numbers are not going to be the same as the d16a6, you don't have the same displacement.
 

farmer_jason

Senior Member
Originally posted by Mech@Apr 2 2003, 10:29 PM
D15B6 (hf, your motor)
.
Displacement (cc): 1493
Power (bhp@rpm): 62@4500
Torque (ft/lbs@rpm): 83@3000
Compression Ratio: 9.1:1
Bore (mm): 75
Stroke (mm): 84.5
Cam Design: sohc
VTEC?: no
OBD: 0
Year(s) Produced: 1988-1989
In the following car(s): Honda Civic HF / CRX HF

With manifold, ecu, and head..... vwalaaa!!:
D16A6 (si.... your upgrade)
.
Displacement (cc): 1590
Power (bhp@rpm): 108@6000
Torque (ft/lbs@rpm): 100@5000
Compression Ratio: 9.1:1
Bore (mm): 75
Stroke (mm): 90
Cam Design: sohc
VTEC?: no
OBD: 0
Year(s) Produced: 1988-1991
In the following car(s): Honda Civic Si/ CRX Si

All in all.... Very worth it. :spin:

your displacement will stay the same which means less torque then the d16a6
 
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