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pnewman |
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#1
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Member ![]() ![]() Group: Members Posts: 371 Joined: 15-February 05 From: Lincolnshire, IL Member No.: 3,606 Region Association: Upper MidWest ![]() |
Time to rebuild my stock 1.8 L Jet
Keeping the L Jet. Any recommendations with the 2056 build in regards to the L Jet -such as cam choice and source etc. -do's / don'ts from your experience. -links to like build threads. Thanks in advance. (IMG:style_emoticons/default/smile.gif) |
914Sixer |
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#2
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,117 Joined: 17-January 05 From: San Angelo Texas Member No.: 3,457 Region Association: Southwest Region ![]() ![]() |
Go to Jake Raby's store. Type4store.com
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Jake Raby |
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#3
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
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Bleyseng |
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#4
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Aircooled Baby! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 13,036 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest ![]() |
96mm P&C's
New Ham Heads with 42x36 valves Raby 9590 cam Porsche swivel feet adjusters Chrome Moly pushrods |
pnewman |
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#5
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Member ![]() ![]() Group: Members Posts: 371 Joined: 15-February 05 From: Lincolnshire, IL Member No.: 3,606 Region Association: Upper MidWest ![]() |
96mm P&C's New Ham Heads with 42x36 valves Raby 9590 cam Porsche swivel feet adjusters Chrome Moly pushrods Thanks, At least it seems as though I am on the right track. Len Hoffman has given me a quote on converting my 1.8 liter heads yep: 42x36 I have 96mm P&C's NOS laying around Had a set of 1.7 rockers machined for the swivel feet adjusters I have a set of swivel feet adjusters and nuts en route. "good" used Porsche oem. ...we'll see THANKS FOR THE ADVISE ON THE CAM! Was wondering if 9590 was too aggressive for the 1.8 liter L-Jet vs stock 2.0 cam. From what I have read some with this combination seemed to have L-Jet adjustment woes. :-( |
ChrisFoley |
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#6
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I am Tangerine Racing ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,981 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None ![]() ![]() |
Was wondering if 9590 was too aggressive for the 1.8 liter L-Jet vs stock 2.0 cam. From what I have read some with this combination seemed to have L-Jet adjustment woes. :-( I've successfully tuned 2.2L L-jet engines with more aggressive cam grinds than the 9590. |
pnewman |
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#7
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Member ![]() ![]() Group: Members Posts: 371 Joined: 15-February 05 From: Lincolnshire, IL Member No.: 3,606 Region Association: Upper MidWest ![]() |
Was wondering if 9590 was too aggressive for the 1.8 liter L-Jet vs stock 2.0 cam. From what I have read some with this combination seemed to have L-Jet adjustment woes. :-( I've successfully tuned 2.2L L-jet engines with more aggressive cam grinds than the 9590. Thanks for the Vote of confidence Chris! (IMG:style_emoticons/default/beerchug.gif) I wonder how smooth they idle. |
Olympic 914 |
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#8
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![]() ![]() ![]() Group: Members Posts: 1,731 Joined: 7-July 11 From: Pittsburgh PA Member No.: 13,287 Region Association: North East States ![]() ![]() |
96mm P&C's New Ham Heads with 42x36 valves Raby 9590 cam Porsche swivel feet adjusters Chrome Moly pushrods You just described my build, with the addition of H-beam rods and a total balance job. I went with the RS+ heads. mine is the D-jet though, I think that might be near the max for the D-jet. maybe the L-jet can handle more. Unfortunately it will be a while until the engine is installed in the car, So I can't give any observations of how it runs. (IMG:style_emoticons/default/confused24.gif) But I think it should be a fun engine. |
pilothyer |
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#9
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Member ![]() ![]() ![]() Group: Members Posts: 838 Joined: 21-May 08 From: N. Alabama Member No.: 9,080 Region Association: South East States ![]() |
Try to get a 86 - 91 Vanagon 2.1 Liter throttle valve (50 mm throat as opposed to the 45 mm on the stock L-Jet) P/N 025 133 067. Lots of info available about this.
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pilothyer |
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#10
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Member ![]() ![]() ![]() Group: Members Posts: 838 Joined: 21-May 08 From: N. Alabama Member No.: 9,080 Region Association: South East States ![]() |
No hijack intended, but what happened to the Raby 9550 cam? and what is the difference between it and the 9590?
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malcolm2 |
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#11
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States ![]() ![]() |
No hijack intended, but what happened to the Raby 9550 cam? and what is the difference between it and the 9590? someone will know for sure, but I believe I heard that soon after I bought my 9550 it was improved and given a new number. Can't remember the number but maybe it is the 9590. Sorry no details and no confidence in the answer, but I bet I am somewhat right> only bet a nickel on it tho. |
malcolm2 |
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#12
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States ![]() ![]() |
No hijack intended, but what happened to the Raby 9550 cam? and what is the difference between it and the 9590? someone will know for sure, but I believe I heard that soon after I bought my 9550 it was improved and given a new number. Can't remember the number but maybe it is the 9590. Sorry no details and no confidence in the answer, but I bet I am somewhat right> only bet a nickel on it tho. |
Jake Raby |
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#13
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
No hijack intended, but what happened to the Raby 9550 cam? and what is the difference between it and the 9590? The 9550 was updated with different lobe separation and exhaust profile in 2011. We did this because the 9550 was old news and the 9590 provided more mid range power with lower running temps. Put simply, the 9590 is the next generation 9550. That said, all the profiles and parts are now LN Engineering products, I sold the Type 4 Store last year. Thank goodness! |
r_towle |
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#14
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
What is the difference is head flow between the stock heads and the RS heads?
Curious how much change is occurring.... |
Jake Raby |
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#15
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
What is the difference is head flow between the stock heads and the RS heads? Curious how much change is occurring.... On a 2056, about 15HP worth of difference back to back. On the flow bench the peak flow is very similar, but where the flow peaks at is different and low lift flow and chamber filling is dramatically increased. The biggest difference is the altered port flow margins between intake and exhaust ports. Remember, peak flow mans a lot less than where the flow is made and what intake : exhaust flow margins are. These port flow margins work really well with the split duration cams that I developed as part of many engine combinations. Here's a graph that was handy from the 2006 offerings, the RS is more refined now than this, but this is the general idea. Remember, this is dry flow data and doesn't show swirl, or tumble, or port velocity. But we have all that data as well. (IMG:http://www.914world.com/bbs2/uploads_offsite/www.aircooledtechnology.com-1095-1415941456.1.jpg) This post has been edited by Jake Raby: Nov 13 2014, 11:04 PM |
r_towle |
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#16
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
What is the difference is head flow between the stock heads and the RS heads? Curious how much change is occurring.... On a 2056, about 15HP worth of difference back to back. On the flow bench the peak flow is very similar, but where the flow peaks at is different and low lift flow and chamber filling can be up by 35%. The biggest difference is the altered port flow margins between intake and exhaust ports. Remember, peak flow mans a lot less than where the flow is made and what intake : exhaust flow margins are. These port flow margins work really well with the split duration cams that I developed as part of many engine combinations. And that increase in flow works ok with DJET? That is kinda why I asked, guy above said he was going with Djet, just curious how it likes that.....cause it does not like a lot of change..... Rich |
Jake Raby |
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#17
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
This is the head that was developed to work with L jet as a primary objective. The L Jet doesn't recognize the changes the heads offer.
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r_towle |
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#18
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
Cool. one of the other poster said he built an engine with those heads running my favorite....Djet.
Just curious if I could try something new....different and push it a bit more... Will wait to see how it runs in his car to see if it's worth pursuing the heads...but I might just to see if it can get a little bit more from djet. |
r_towle |
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#19
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
96mm P&C's New Ham Heads with 42x36 valves Raby 9590 cam Porsche swivel feet adjusters Chrome Moly pushrods You just described my build, with the addition of H-beam rods and a total balance job. I went with the RS+ heads. mine is the D-jet though, I think that might be near the max for the D-jet. maybe the L-jet can handle more. Unfortunately it will be a while until the engine is installed in the car, So I can't give any observations of how it runs. (IMG:style_emoticons/default/confused24.gif) But I think it should be a fun engine. This guy... |
Jake Raby |
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#20
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Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
9590+RS Plus & 8.5:1 with tight deck will make 110-115HP safely.
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