 Differences in Exhaust Port Shape ? |
|
|
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
|
  |
| Literati914 |
 Sep 7 2019, 10:59 PM
Post
#1
|
|
Senior Member  Group: Members Posts: 1,461 Joined: 16-November 06 From: Dallas, TX Member No.: 7,222 Region Association: Southwest Region  |
I know people use 1.7/1.8 exhausts on 2.0L /4s and vise versa all the time - but someone I thought knew what he was talking about, made the following statement to me the other day and I thought 'woa, bullcrap!, don't think so'... but it's had me thinking ever since.
"I know on the 2.0 litter exhaust ports heads are more of a rectangular squared shape vs. the 1.7,1.8 are a true oval shape port" So, is that actually the case, or not? |
   |
 
|
| Tbrown4x4 |
Sep 7 2019, 11:59 PM
Post
#2
|
|
Senior Member Group: Members Posts: 704 Joined: 13-May 14 From: Port Orchard, WA Member No.: 17,338 Region Association: None 
|
2.0L vanagon heads had a squarer shape after 1978(?). I don't think his statement applies to the 2.0 Porsche heads on the 914.
|
|
|
|
| porschetub |
Sep 8 2019, 01:02 AM
Post
#3
|
|
Advanced Member Group: Members Posts: 4,699 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
QUOTE(Literati914 @ Sep 8 2019, 04:59 PM)  I know people use 1.7/1.8 exhausts on 2.0L /4s and vise versa all the time - but someone I thought knew what he was talking about, made the following statement to me the other day and I thought 'woa, bullcrap!, don't think so'... but it's had me thinking ever since. "I know on the 2.0 litter exhaust ports heads are more of a rectangular squared shape vs. the 1.7,1.8 are a true oval shape port" So, is that actually the case, or not? Please read on , later than our motors ,thank god as exhaust options are very limited ,and I seem to remember very small valves…. |
|
|
|
| rick 918-S |
Sep 8 2019, 05:29 AM
Post
#4
|
|
Hey nice rack! -Celette Group: Members Posts: 20,460 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region 
|
Crappy bus 2.0 heads have square ports
|
|
|
|
| ClayPerrine |
Sep 8 2019, 05:37 AM
Post
#5
|
|
Life's been good to me so far..... Group: Admin Posts: 15,469 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille
|
All 914 heat exchangers will fit all 914 heads. Square ports were never used on 914 heads at all.
But.. you want to use the 2.0 heat exchangers for best performance. |
 |
|
| rick 918-S |
Sep 8 2019, 05:42 AM
Post
#6
|
|
Hey nice rack! -Celette Group: Members Posts: 20,460 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region
|
QUOTE(ClayPerrine @ Sep 8 2019, 06:37 AM) All 914 heat exchangers will fit all 914 heads. Square ports were never used on 914 heads at all. But.. you want to use the 2.0 heat exchangers for best performance. Clay, aren't the inside tube diameters the same? The only difference is the up lift at the rear of the tubes on the 1.7 set. |
|
|
|
| ClayPerrine |
Sep 8 2019, 06:08 AM
Post
#7
|
|
Life's been good to me so far..... Group: Admin Posts: 15,469 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille
|
QUOTE(rick 918-S @ Sep 8 2019, 06:42 AM) QUOTE(ClayPerrine @ Sep 8 2019, 06:37 AM) All 914 heat exchangers will fit all 914 heads. Square ports were never used on 914 heads at all. But.. you want to use the 2.0 heat exchangers for best performance. Clay, aren't the inside tube diameters the same? The only difference is the up lift at the rear of the tubes on the 1.7 set. I think the 2.0 tubes are bigger, at least from looking at the muffler gaskets. The 1.7 exchangers use a steel casting to connect to the head, the 1.8 and 2.0 use loops welded to the tubes. The steel casting doesn't flow as well as the tubes. And the 2.0 exchangers flow better due to the straight tubes at the rear. |
|
|
|
| Olympic 914 |
Sep 8 2019, 08:51 AM
Post
#8
|
|
Group: Members Posts: 1,670 Joined: 7-July 11 From: Pittsburgh PA Member No.: 13,287 Region Association: North East States
|
On the SS Heat exchangers the tubes are the same for the 1.7/1.8 and 2.0 with the only difference being the bends on the end where the muffler mounts.
On the original steel units, the 1.7 tubes are smaller than the 2.0 |
|
|
|
|
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 18th May 2024 - 06:01 AM |
Invision Power Board
v9.1.4 © 2024 IPS, Inc.