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1.9 combo's

Posted: Sun Nov 24, 2013 4:47 pm
by jackstraw
Greetings. Picked up an '85 Weekender just over a year ago. 1.9, four speed. Pop top.

I'm thinking of ways to design a small thumper that will be fun to build. I see no love for the DH and I want to give it some.

I like the 94 x 69 combo. I beat up on it for what it is, long shifting just to stay, "on the pipe".

I have recently come across a couple of cams that have a bit wider LSA than norm and should allow to get some torque in the mid to upper range. I cruise around in third a lot. I do not have a tach but drive by the orange tick marks on the speedo. Third winds out to 65. Crower has two with 110*. CB has the 2228 at 112*. I've been partial to Isky for more than a couple of decades. The CB 2280 might be a bit much for the 1.9. Dunno. Need help with that thought.

My first thought is to add a bit more rod and shave the piston tops. I do not how much I can clip from the pistons or how much more rod before case mods.

I don't have a problem with a bump in CR. I won't really be able to determine cam choice until I tear a core down for blueprinting.
It's all about that Static and Dynamic thing.

Anyway, thanks for reading. My head isn't trying to reinvent anything. Kinda thought this might be a fun winter project. Maybe something worthy to hang a respected exhaust onto, huh?

Re: 1.9 combo's

Posted: Mon Nov 25, 2013 9:19 am
by buildabiggerboxer
In my view, THE starting point is the 2.1 crank swap, the torque gain is exactly whats required for a bus, you can work your socks of on the 1.9 and the 2.1's will still out pull them, you will also need to find 2.1 pistons, they are shorter than 1.9's, then i would find an AAP 5 sp trans, again, the 5 speed is faster over a mountain than a four, you CAN use the box with the 4 sp shifter, it just needs a little imagination to make them work reasonably well.

Re: 1.9 combo's

Posted: Mon Nov 25, 2013 4:11 pm
by jackstraw
Cool. Thanks. There has to be a reason that the 1.9 had a short life span from the factory.

I have entertained a GW crank kit. But I might as well just get a Vanistan engine.

I was thinking that the 1.9 could be made into an rpm engine. Wasser's have the inherent low end torque.

I'll give it some more thought after I finish my beer.

Thanks again,

Re: 1.9 combo's

Posted: Mon Nov 25, 2013 6:53 pm
by jackstraw
Is the pin height different or the same regarding the 1.9 and the 2.1?
You mention the 2.1 is shorter. Maybe this is skirt length.
I didn't see anything in the Bentley

Re: 1.9 combo's

Posted: Mon Nov 25, 2013 7:55 pm
by sideshow
The difference in stroke is accounted for in the piston, 76mm pistons are needed.

Re: 1.9 combo's

Posted: Fri May 09, 2014 3:53 pm
by revD
Jackstraw I am thinking about the same thing, looking to bump the CR with my 1.9 and add a cam - looking for better gas mileage in my double cab not necessarily max power, let me know if you come across something. I was looking at 5.5" rods stock are I believe 137mm / 5.39" then see if the tops of pistons can shaved just like you mention, I just havent calced the CR yet.

Re: 1.9 combo's

Posted: Fri May 09, 2014 5:06 pm
by jackstraw
I haven't been able to cc anything yet. So , I can't use a dynamic CR formula.

But, within the dream cloud, past experience notions, I would think that
using a longer rod-shave the piston tops and keep in the mid 220* @ .050 range should yield in the mid to upper 7's on the
DCR scale. Totally doable.

At least with Digijet, we can pull some timing out of it if it pings. But then again, we have the Heron style engine and it can tolerate
higher compression.
Low compression, lots of timing. Or, high compression, reduced timing. Take the vacuum out of it and keep the mechanical pegged at 30*. Should rpm all day long and stay cool. Sort of the best of both worlds between AC and Wasser

The 1915 AC boyz are getting 100 hp all day long. Even a 1776.
We should be able to do that also, huh?

While juggling what to do, i still keep the turbo thing simmering on the burner, but that's another thread.

Ah, bench racing. gotta love it

Re: 1.9 combo's

Posted: Fri May 09, 2014 5:31 pm
by revD
yup good stuff, just realized this is from 6 months ago - you haven't built this yet?! just too many combos to do i guess... I was thinking the 2280 cam based on how CB describes and good reviews here. And the timing how you mention is also a good point. Should be able to get a good bump over the 80hp atleast.

Re: 1.9 combo's

Posted: Fri May 09, 2014 5:45 pm
by jackstraw
Life, wife, kidz. Kinda slowz things down. Sorry.

Re: 1.9 combo's

Posted: Wed May 14, 2014 6:04 pm
by revD
I was just teasin, I have too many projects also. trying to take apart the spare motor on the long weekend. I think Rocky jennings might still do the 1mm longer rods that may accomplish what we are looking for or I see some have ditched the head gasket/spacerto help with CR

Re: 1.9 combo's

Posted: Wed May 14, 2014 9:12 pm
by jackstraw
Personally, I wouldn't be comfortable until I can cc everything to get a true static so I can plug in cam numbers for the dynamic with the intended rpm range.

Some builders use recon rods. Great but they end up shorter which puts the piston in the hole.
So even to do a blueprint, it seems to me that one has to start with longer rods.

Nice to bench race but can never forget that we'd be dealing with nineteen hundred fifteen cc's.
Great engine for a Bug?

RJE site says OE rods on 2.1 - 2.3. How do you set deck height with a recon rod that ends up shorter.

GW's 2.3 kit says recon rods.

So how would I keep the deck tight. I'm just askin'
I have more questions than answers

Re: 1.9 combo's

Posted: Fri May 06, 2016 5:47 pm
by jackstraw
Shiza. Has it been damn near two years. Those darn kids keep gettin in da way.
I've been using the search and reading up on rods. But..
The big question is with regards to replacing the rods , be it for the 1.9 or 2.1, that are a bit longer so as to shave the piston tops a wee bit for a slight increase in CR if nothing else, what are my choices?
I find more 5.5's unless I'm looking in the wrong place.

Re: 1.9 combo's

Posted: Sat May 07, 2016 4:43 pm
by jackstraw

Re: 1.9 combo's

Posted: Mon May 09, 2016 4:44 am
by AMBROSIA
I went with Scat I beams and had the pins bored and reamed to 24mm.
If your looking at shaving pistons I would ditch the stock ones and get something suitable with a 22mm pin.
There's not a great deal of spare meat on the small ends and it looks like my machinist reamed the bronze bushes pretty thin.
Also upgrade the bolts to ARP.

I would agree with BBB that the 2.1 wins hands down on torque having run both.
The CB hydro cam certainly boosts the torque on a 2.1.
I ran a CB 2252, 1.25 rockers, dual 40 dells with an extractor exhaust and gained 10 HP over the stock FI setup.

BTW 1.9 engines work really well with turbo's, just sayin'

Re: 1.9 combo's

Posted: Mon May 16, 2016 5:30 pm
by jackstraw
yep. It would be nice to browse the boneyard and adapt a complete turbo swap onto a 1.9 DH.

Regarding rods. When I convert the stock 137 into 5.39 and then see that a 138 rod is 5.43, is there enough meat to shave at the piston top and use a 5.5 rod?

I'm stuck with Cali Land smog laws . I'm not trying to reinvent anything. Just looking for an improved WBX recipe that can get the flywheel torque in the low 130's. Maybe upper.
A bit more compression and some cam, dial in the DCR to 8.0 max. I should be happy.