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.

Go to Jake Raby's store. Type4store.com

Its the LN Engineering Type 4 Store, has been for a year now :-)

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. :-(

I've successfully tuned 2.2L L-jet engines with more aggressive cam grinds than the 9590.

Thanks for the Vote of confidence Chris!
I wonder how smooth they idle.

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.

But I think it should be a fun engine.

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.

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.

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.

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!

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.

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

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.

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.

This guy...

9590+RS Plus & 8.5:1 with tight deck will make 110-115HP safely.

I bet I got the last one! I ordered a 9550 kit on a Friday. The following Monday they announced that 9550 was discontinued and replaced with 9590. So on my next build I guess I'll go with the 9590. They say timing is everything and my life is full of stories of being a day late or in this case a day early. I'd be disappointed except that my engine runs so sweet and gets 33-35mpg. So thanks Jake for the engineering, and Len for the head and case work and a little advice, and LN for taking on the store.

And in another sense, I guess timing IS everything! A good engineer's motto.

THANKS!! You probably did get the last one. I kept one for the museum, though :-)

That's flow data from two generations ago. We blew past that a while ago. We no longer put flow data out for public consumption, but let's just say that the current version of the RS+ is substantially more potent. That data was from the transition version when the RS+ superseded the LE-180.
Here's a link to our facebook page with pics of the latest RS+
https://www.facebook.com/HoffmanAutomotiveMachine?ref=br_rs
Our latest heads with the upgraded cam offerings will make for an even stouter power-plant than even just a few years ago.

Will be awhile till it runs. the engine is done



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But the body work is progressing slowly.



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Damn, don't know why the picture did that..???


Fixed....