I was considering doing a head job and changing the pistons and cylinders on my 1.8 liter while I have it out.

What are the oem cylinders? 70 mm? I have seen people peddling "94mm" I am not looking at doing dual carbs right now.



Can I go larger and still use the stock L jetronic Fuel Injection system that I have kept well maintained over the years?

teh limit is going to be your heads....your fine with the larger pistons.

the 912E was an example of a modified L-jet system to fit a 2.0

it's more expandable than D-jet in some ways...dont go wild on the cam though.

b

Just make sure you get the correct pistons for your setup. There are different wrist pin heights.

stock bore is 93 mm for the 1.8 liter.
Stock bore is 94mm for the 2.0 liter...

rich

You can run the larger 96mm ones but get the right wrist pin height for a 66mm stroke.

How much will be gained by upping the oem 93mm pistons to 96mm and playing with the wrist pin height and the heads to match?

vs.

oem 93mm (3mm less) pistons and an oem head job.

and how will my oem L jet system react to the increases?



Also is there a one stop shopping source for a correct match heads and pistons for this set up? any one can do oem, but upgrades require someone with specific backround.

thanks, Pete

increasing the bore to 96mm gives you a 6% increase in displacement, so....in theory, you should get a 6% increase in power.....

also, the larger bore will give you a tad bit more compression with everything else equal...again a little more power.....

for the heads, I'd just do a stock rebuild, not sure if the money is worth it for a 3-angle valve job or not, but it couldn't hurt...

the 1911 with the L-Jet is a good combo and you'll like it...

for the pistons/cylinders:
aircooled technology,
aircooled.net (?)
your local shop possibly


heads:
LEM,
rimco,
local shop?

Thanks for the info!

Will those sources if given my info know what the right wrist pin height should be?

Also, A stock head job will be fine w/ 96 mm's?

Thanks, Pete

For more hp I would send them to Len at HAM to rebuild and install 42x36 valves. Will help to build some hp along with the 96mm pistons.
A cam change would also help esp to cool the oil temps down.

I am looking into 96mm's w/ stock heads. Again I am trying to avoid converting from oem EFI to carbs.

Can I stay stock fuel w/ 96's and upping the valves?

What adjustments if any would have to be done to EFI and timing to accomodate this increase?

I was told that going to 96mm's I would have to watch the compression? Do they mean stroke> What is stock stroke w/ the 1.8 93mm's 70mm's? Therefore what do I need w/ the 96's?

I was also trying to avoid cracking the case so I am not interested in doing a cam right now.

I really appreciate the input,

Thanks Pete

Keeping the stock EFI means keeping the stock cam. :puke:

Moving to a better cam can free up as much as 30 hp. But it means ditching the stock injection. Aftermarket injection will take dyno time to tune in well ($500), but carbs can be made to work well with just some "ear tuning". I'm a huge FI fan, but I like anything over the stock FI. Especially if you are looking to gain a little power.

a cam change would require for most parts a complete engine rebuild, the guy is only looking to freshen up the top end......


your engine specs should be:

93 bore X 66 stroke
7.3 compression

with the 96mm bore, the stroke stays the same, the compression goes up to 7.6

ask for 96mm big bore Piston/cylinder kit for a 1.8

if you go this route, nothing should have to be done to the stock FI, just reassemble the freshened up heads, install the new pistons and cylinders and fire the puppy up and enjoy it....don't expect huge gains, but it should be much better than before if the engine is tired.....

Why not increasing the compression to 8.5 or even 9.0? That would free up some ponies

Louis

Hi

Got some good advice here, Big bore with fresh heads is a nice combo, without droppin lots of $$$.
Pay special attention to the valve geometry/ heights, this is so important after the cyl have been replaced. Nothing worse then doin it twice.

Good luck with it

Louis, Type 4s need a lot of work to keep the heads on the motor stock, bumping the compression is always a good HP thing, bad head thing. Higher compression is usually saved for the bigger $$$ rebiulds.

Later

I'd definitely go to the 96mm cylinders at least. Gives you 1911 displacment, and an engine that likes to rev.
I rebuilt my 1.8 last winter to that size, but used a web 86 cam, did a bit of head work, and raised the compression to 8.6/1. with dellorto carbs.
It was an amazing boost in hp in a fast reving engine. Made the car much more fun to drive.
Changing the cam is no big deal, and I think where most of the increase came from, but be aware that if you do change the cam you won't be able to use the stock injection system. Carbs or aftermarket injection is the expensive part.
Too bad the stock cam is such a dog.

QUOTE (MecGen @ Dec 12 2005, 04:10 AM)

Louis, Type 4s need a lot of work to keep the heads on the motor stock, bumping the compression is always a good HP thing, bad head thing. Higher compression is usually saved for the bigger $$$ rebiulds.

MecGen,

what exactly do you mean?

You can raise the compression to 8to1 with the stock cam, with higher it gets too hot. You can use a Jake Raby cam that does bleed off more of the exhaust heat and still run the stock FI plus gain a little hp.
Bigger valves help too as they help increase the efficentcy and bleed off heat out of the combustion chamber.

That cam goes on end of the year overstock special today! As soona s I can get it posted!

QUOTE (Bleyseng @ Dec 11 2005, 04:03 PM)

For more hp I would send them to Len at HAM to rebuild and install 42x36 valves. Will help to build some hp along with the 96mm pistons. A cam change would also help esp to cool the oil temps down.

L jet hates cam changes even more than D jet. The Cap'n

Yep, but the cams I use for each are more times than not EASIER to tune than the stocker is... They yield a better powerband and cooler heads as well...

QUOTE (Jake Raby @ Dec 12 2005, 10:35 AM)

That cam goes on end of the year overstock special today! As soona s I can get it posted!

does this cam you speak of help a 2.0 liter djet, or is this for carbs???

Rich

QUOTE (Jake Raby @ Dec 12 2005, 08:31 AM)

Yep, but the cams I use for each are more times than not EASIER to tune than the stocker is... They yield a better powerband and cooler heads as well...

My post went in much earlier in the discussion than it appears, Jake. What I meant was "ordinary" non-stock cams don't work with L jet, despite what the salesman tells you. The Cap'n

The cam I was speaking of was developed specifically for stock EFI. I have one for D jet and one for L jet since their characteristics are different..

I have 30+ cams for carbs according to head work and etc...
Yes cap'n I know all about those salesman that have clean hands

I have this P&C combo with L-jet on my motor.
I like the quick revs it produces. Very fun to drive.
I only wish I had used better quality P&Cs though.

Jake, I haven't forgotten to call. Just experiencing schedule delays....

QUOTE (Bleyseng @ Dec 12 2005, 06:59 AM)

You can raise the compression to 8to1 with the stock cam, with higher it gets too hot. You can use a Jake Raby cam that does bleed off more of the exhaust heat and still run the stock FI plus gain a little hp. Bigger valves help too as they help increase the efficentcy and bleed off heat out of the combustion chamber.

Here in Europe there was an 1.8 engine (code: AN, same as 412S) with 85 HP and two 40 Solex carburettors. The compression was as high as 8.6. The cam should be the same in all stock engines!?

Wouldn't it be possible simply to increase the compressión of the EC engine to the specs of the AN engine to get 85 HP?

Cheers,

Louis

The cams are NOT the same...

There were 11 stock cams and the AN engines I have torn down had their own camshaft.

QUOTE (Jake Raby @ Dec 15 2005, 09:23 AM)

The cams are NOT the same... There were 11 stock cams and the AN engines I have torn down had their own camshaft.

Good to know. Thank you, Jake!

I have a new set of Euro 1.8L P&C's. They have a dombed piston like the 1.7L. They are still in the box. I also have a set of 1.8 flycut and opened up heads. Len Hoffman installed oversized seats for me because these heads have duel springs. $850 for both and I'll through in a set of lightened rods. Al

Best bang for your buck would be to use a complete 2.0 bottom end and throw your 1.8 heads on it. Putting a lot of money in the heads won't do you too good with the OEM FI and cam setup since making radical changes to the head won't help with that anemic FI cam. Once you've got your 1.8 heads on a 2.0 bottom end with 96mm pistons, go with 912E injectors, they're larger and have the proper variables to use with your L-Jet system. You shouldn't even have to adjust your Air Flow Sensor (barn-door flapper) with that combination. Costs less than a complete 2.0 and will give you a good 90-100 HP. Don't expect miracles with L-Jet though.

I THINK you may need to get your case opened up for those 96mm cylinders to slide right in. I'm not 100% sure about that, though. It's only money, right?

96mm piston/cylinder kits are drop ins... No machining required.

W/ 96 mm p & c kits should I do anything to the heads to maximize the benifit?

Will I need to do anything to the OEM EFI Ljet system? i.e. will it run to lean or too rich w/ the 96's?

thanks for your input
Pete

QUOTE (pnewman @ Dec 16 2005, 10:43 AM)

W/ 96 mm p & c kits should I do anything to the heads to maximize the benifit? Will I need to do anything to the OEM EFI Ljet system?  i.e. will it run to lean or too rich w/ the 96's? thanks for your input Pete

^ That's why I suggested the 912E injectors. They're sized for a 2.0L and are designed for L-JET. You shouldn't have to adjust your Air Flow Sensor, but I'd get it on a dyno or a flexible gas analyzer to see if you are running rich or lean through the RPM range once you make the swap.

As for the heads, a valve job, new seats and stainless valves should do you fine. Having radical work done to 1.8 heads for OEM FI is a moot point, unless you want to go with megasquirt and then you get into cracking the case for a cam change.

The STOCK 1.8 head is good for up to 2200ccs, as long as you don't wanna rev it to 7K...

slap it together with 96mm and go! check deck height and CC your heads, of course
my 1.8 with L-Jet and 96mms ran great. I set it to 8.3 to 1

I dont know how much it helped but I also match ported teh exhaust ports to teh heat exchangers. I used a used exh copper gasket as a guide. I also blended the seats and that nasty short radius on the exhaust port

Jake: how much do you think all that grinding helped?

Is the cam differnt between a OE Ljet 1.8 and OE Djet equiped 1.7? I assume it would be. Which would be preferential?

insert popcorn eating smiley face here: