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Posted by: DennisO Aug 6 2017, 08:56 AM

Hi All,

I plan to rebuild the 1.8L in my '75 project. The engine is original and complete with the L-jet fuel injection. I want to keep the original L-Jet Fuel Injection and was wondering what are good P&C sets for this engine if I don't want to change the fuel injection system? Reliability is my highest priority for the rebuild.

The PET catalog has 022198075A listed as the part number for 1.8L, but it also has this part number listed for the 2.0, so I'm not sure if it's correct. Is Mahle the OEM vendor for these engines?

Thanks in Advance,
Dennis

Posted by: McMark Aug 6 2017, 11:19 AM

L-Jet is capable of running a larger engine. I would put in 96mm pistons and cylinders (for 66mm stroke).

If you need to rebuild to the stock 1.8, the new P&C sets from Mahle can be a bit hit or miss in terms of quality control (from what I've heard). I've never used OEM P&C because most people want the extra power from 96s.

Posted by: DennisO Aug 6 2017, 11:36 AM

Thanks - good to know about new Mahle.
Are the stock 1.8L Pistons 93mm?

I'm interpreting your statement as I can run 96mm pistons keeping the 1.8 stock crank, rods, and L-Jet. Is that correct? Do I need to mod the case to fit 96mm pistons?
L-Jet is capable of running a larger engine. I would put in 96mm pistons and cylinders (for 66mm stroke).

Thanks for the help.

Posted by: jim_hoyland Aug 6 2017, 04:37 PM

I just did the 96mm pistons. I also upgraded the TB to the larger Vanagon 2.1

Posted by: Dave_Darling Aug 6 2017, 05:21 PM

Stock 1.8L cylinders are 93mm diameter.

The 96mm P&Cs will bolt right up to a 1.8 motor with no further modifications. Supposedly there are zero problems running L-jet on that combination which is 1911cc. I would be tempted to run a wide-band O2 meter on it to make sure it doesn't lean out at high RPM and wide-open throttle settings, though.

--DD

Posted by: DennisO Aug 6 2017, 06:41 PM

Dave,

Do the 96mm pistons raise the compression ratio as well? According to info i found on the the web, it listed stock 1.8L compression ratio at 7.3:1. Any particular brand you would recommend?

Thanks,
Dennis

Posted by: DennisO Aug 6 2017, 07:05 PM

Hi Jim,

thanks for the info. Do you have the p/n for the vanagaon TB? Does it easily connected or does it require wiring or other mods? What brand p&C dod you use?

Thanks,
Dennis

Posted by: jim_hoyland Aug 6 2017, 08:20 PM

See the thread: http://www.914world.com/bbs2/index.php?showtopic=244849&hl=vanagon++throttle

I bought a used 2.1 Vanagon TB on eBay then sent it to Phil in New Mexico for replacing the shaft and installing new bushings; it came back looking like new. Whether the TPS makes any difference with an L-jet is questionable. Others on the board have run their L-jet without the TPS hooked up and found no issues. You can try this now with your current TB; unplug the connector and do a test drive.
I also installed the K & N air filter in the box.

The pistons were Mahle IIRC
Also, check the GoWesty web site; they sell vanagon parts including the TBs

Posted by: DennisO Aug 6 2017, 08:24 PM

thanks!

Posted by: jim_hoyland Aug 6 2017, 09:25 PM

This is the TB restoration link:
pbeslins@msn.com

He advertises on The Samba and appears to be a machinist. His work is outstanding

Posted by: McMark Aug 7 2017, 06:13 AM

https://aapistons.com/collections/vw-piston-liner-kits/products/vw-porsche-96mm-big-bore-piston-cylinder-kit-914-bus

You'll need to calculate the compression ratio (CR) and make the changes you need to to get the CR where you want it to be. Put in 96 and jump the CR up to around 8.5:1 and you'll have a nice little upgrade.

Posted by: JOEPROPER Aug 7 2017, 06:20 AM

What is the recommended camshaft or cylinder head upgrade??

Posted by: McMark Aug 7 2017, 06:31 AM

Cam entirely depends on the rest of the combo. At the very least, it's necessary to know if it'll be carbs or fuel injection. For this thread, we're talking about a L-Jet motor, so for better drivability I would use the stock cam. To swap a little drivability for a little more power, get the WebCam 73.

Heads for performance would be
1. 914 2.0 heads, if you want to stay $1000 or under.
2. Len Hoffman RS+ heads, if you want the very best. But these would be overkill for a stock-ish motor. So, again, it depends on the rest of the combo and the intended use.

Posted by: DennisO Aug 7 2017, 08:22 AM

Wow - this is exvellent info. Thank you.

I received an email offering me a NOS set of NPR 96mm for a 914 1.8. I cant find any info on them on the web. Are NPR any good and they are no longer being made?

Posted by: echocanyons Aug 7 2017, 08:31 AM

Lots of great information on this thread.

What would be necessary to do if you were to use 96mm P&Cs and a 2.0L crank?

Could you use the 1.8L rods?
Does this require case machining?
Would the stock 1.8L cam still be suitable?

Posted by: McMark Aug 7 2017, 11:17 AM

66mm cranks (1.7/1.8) have a larger 'big end' on the connecting rod. So rods from 1.7/1.8 won't work with 2.0 cranks (and visa versa).

The 2.0 rods are also longer than the 1.7/1.8 rods. And that's the difference between P&C sets. The wrist pin in the 2.0 sets is higher. Installed a set of P&C for a 1.7/1.8 onto a set of 2.0 crank and rods will result in the pistons extending beyond the top of the cylinder, and using a set of P&C for a 2.0 on a 1.7/1.8 will result in an unusably low compression ratio. You must buy pistons that match the crank/rod setup you have.

No combination of Type 4 engine requires case or head machining, with two exceptions. 1.7 heads have a smaller bore, so those need to be opened up for use on a 1911 upgrade. Also, some large P&C sizes (103mm pistons) need the cases opened up. But for every popular combination that people are building, everything is interchangeable.

All Type4 stock cams are the same. They're a non-overlap cam, which makes a great vacuum signal for the fuel injection. But gives up horsepower because of that. Valve overlap builds power, but sacrifices vacuum and consistent airflow at idle. The stock cam can be used with stock FI, carbs, or aftermarket FI. There are better choices for almost every combination and setup, but the stock cam will work okay.

Posted by: jim_hoyland Aug 7 2017, 02:49 PM

One other thing that helped was the replacement of the stock distributer Earlier I picked up a Mallory Unilite #4554101 optical distributor from Chris at Tangerine Racing.
Mallory was subsequently merged with MSD; that particular unit may have been discontinued. The result was better / smoother acceleration through a wide range of RPMs, no pinging on hills, and engine ran cooler.

Posted by: jsaum Aug 7 2017, 06:49 PM

I think I've read that the rings aren't great quality on this set. What rings would you recommend?

Posted by: DennisO Aug 7 2017, 09:49 PM

thanks Guys. What a wealth of great info.

The slippery slope is starting:-)

So to summarize what I read:
- change to 96mm pistons - increases displacement, compression ratio, and will work on stock 1.8 case (no mods to case)
- Cam - can keep stock, but change if I want to get sporty
- heads - No mods required for 96mm pistons
- L-jet FI - can keep stock, but larger TB improves performance
- Any comments on NOS NPR vs AA P&C Sets?
- Any recommendations to improve engine cooling?

Thanks!

Posted by: porschetub Aug 7 2017, 11:30 PM

Appears the rings are changed to Grant or similar US made...far as I can tell???

Posted by: jim_hoyland Aug 8 2017, 05:31 AM

Rings need to get seated properly: there are procedures posted to ensure this. Didn't take that much time.
Engine temps were not affected

Posted by: wndsrfr Aug 8 2017, 06:11 AM

Use your cylinders, have them bored to fit the 96mm pistons. Those cylinders will be more stable than a new set....

Posted by: saigon71 Aug 8 2017, 06:29 AM

I offer another cam option. When building my 2056 with stock D-Jet, I went with the FAT 440MP camshaft. It's in between the stock grind and the WebCam 73. You gain some power without losing any drivability.

Posted by: bernbomb914 Aug 8 2017, 09:00 PM

Iused Jahns Pistons told them what rods I was using

Posted by: porschetub Aug 8 2017, 11:31 PM

Sorry forgot Hastings rings are used also ,appears the originals aren't too flash so most rehone and use these,,this is second hand info so take it however u like.