Need stock compression PSI for B16, B17, B18A, B18C1, and B20

ASSISTANCE Stock Engine-Bay Components
1

I need stock compression PSI numbers for B16, B17, B18A, B18C1, and B20 motors.

I searched but was only able to find what other people were getting or what some guy down at the local tuner shop said. I need numbers from a Helms or something.

TIA

2

Helms Manual stock compression numbers:

B18A1 - 185 PSI
B17A1 - 184 PSI

3

Originally posted by Tapioca
[B]Helms Manual stock compression numbers:

B18A1 - 185 PSI
B17A1 - 184 PSI [/B]

Uhhh, no.

Not only is this wrong but it doesnt even make sense. The B17 has higher compression than the b18. I just checked the compression on my b17 a few days ago and it read 200 psi on all cylinders. One would imagine it is somewhat higher than that as my engine is 165,000 miles old.

4

ya those numbers don’t quite make sense, maybe they are service limits or something?

C’mon…someones gotta know this…

5

Originally posted by Tapioca
[B]Helms Manual stock compression numbers:

B18A1 - 185 PSI
B17A1 - 184 PSI [/B]

I thought the B18A was 205 new? Mine checked out at 204-205 across all 4 cylinders when I got it a few months ago (91 w/120k). I’d be prone to think those are service limits too - even my beat to shit 170k mile 96 Civic was putting out 155… (on 2 cylinders, 80 and 90 on the others)

6

Nominal: 185psi
Minimum: 135psi
Max Variation: 28psi (or 15%)

Most B18As I check out come out at 180-190psi. The real important thing is that there is not more than 15% variation between the cylinders. I don’t like more than 5% variation.

I hope this helps you out. Let me know if you need anything else.

7

ya those numbers don’t quite make sense, maybe they are service limits or something?

I took these numbers straight out of the Helms manual and the Guru himself has backed me on those numbers.

8

thanks for the clarification :up:

anyone got numbers for the rest of the motors?

9

then why does everyone’s stock b18/17 get 200 psi? Is there something wrong with my engine that the compression is so high?

10

Maybe the carbon’s built up enough to increase the compression. Maybe your gauge is inaccurate. Could be lots of little things.

11

Yea get a Snap-On comp. gauge, cheap gauges dont give very acurate readings!.

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Re: Need stock compression PSI for B16, B17, B18A, B18C1, and B20

Originally posted by Haberdasher
[B]I need stock compression PSI numbers for B16, B17, B18A, B18C1, and B20 motors.

I searched but was only able to find what other people were getting or what some guy down at the local tuner shop said. I need numbers from a Helms or something.

TIA [/B]

Hey Dave,

Here’s what I have based on the Helms manuals:

B16A1 (1st Generation)

Nominal: 185psi.
Minimum: 135psi.
Maximum Variation: 28psi.

B17A1

Nominal: 184psi.
Minimum: 135psi.
Maximum Variation: 28psi.

B18A1

Nominal: 185psi.
Minimum: 135psi.
Maximum Variation: 28psi.

B18B1 (1994 Helms)

Nominal: 199psi.
Minimum: 140psi.
Maximum Variation: 28psi.

B18C1 (1994 Helms)

Nominal: 270psi.
Minimum: 140psi.
Maximum Variation: 28psi.

Regards,

Oz

13

wooohoooo…you rock…thank you :up:

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BTW, sorry man. Can’t find specs for the B20. Don’t have a CRV manual handy.

:frowning:

Oz

15

that’s great info,

i have a b17 with 160psi on all cyl which mean, i’m doing fine with these numbers up there…

16

I have a 92 GSR w/ 125xxx, and i got 205-210 on all cyl.
Is that bad?