P&C Set Recommendations for a 1.8L Rebuild |
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P&C Set Recommendations for a 1.8L Rebuild |
DennisO |
Aug 6 2017, 08:56 AM
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#1
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Member Group: Members Posts: 61 Joined: 9-June 17 From: Clayton, NC Member No.: 21,162 Region Association: South East States |
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 |
McMark |
Aug 6 2017, 11:19 AM
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#2
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
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. |
DennisO |
Aug 6 2017, 11:36 AM
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#3
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Member Group: Members Posts: 61 Joined: 9-June 17 From: Clayton, NC Member No.: 21,162 Region Association: South East States |
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. 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. |
jim_hoyland |
Aug 6 2017, 04:37 PM
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#4
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Get that VIN ? Group: Members Posts: 9,319 Joined: 1-May 03 From: Sunset Beach, CA Member No.: 643 Region Association: Southern California |
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. (IMG:style_emoticons/default/agree.gif) I just did the 96mm pistons. I also upgraded the TB to the larger Vanagon 2.1 |
Dave_Darling |
Aug 6 2017, 05:21 PM
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#5
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914 Idiot Group: Members Posts: 14,991 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
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 |
DennisO |
Aug 6 2017, 06:41 PM
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#6
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Member Group: Members Posts: 61 Joined: 9-June 17 From: Clayton, NC Member No.: 21,162 Region Association: South East States |
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 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 |
DennisO |
Aug 6 2017, 07:05 PM
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#7
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Member Group: Members Posts: 61 Joined: 9-June 17 From: Clayton, NC Member No.: 21,162 Region Association: South East States |
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 |
jim_hoyland |
Aug 6 2017, 08:20 PM
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#8
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Get that VIN ? Group: Members Posts: 9,319 Joined: 1-May 03 From: Sunset Beach, CA Member No.: 643 Region Association: Southern California |
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 See the thread: http://www.914world.com/bbs2/index.php?sho...nagon++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 |
DennisO |
Aug 6 2017, 08:24 PM
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#9
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Member Group: Members Posts: 61 Joined: 9-June 17 From: Clayton, NC Member No.: 21,162 Region Association: South East States |
thanks!
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jim_hoyland |
Aug 6 2017, 09:25 PM
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#10
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Get that VIN ? Group: Members Posts: 9,319 Joined: 1-May 03 From: Sunset Beach, CA Member No.: 643 Region Association: Southern California |
This is the TB restoration link:
pbeslins@msn.com He advertises on The Samba and appears to be a machinist. His work is outstanding |
McMark |
Aug 7 2017, 06:13 AM
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#11
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Get these 96s.
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. |
JOEPROPER |
Aug 7 2017, 06:20 AM
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#12
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The answer is "no" unless you ask... Group: Members Posts: 1,184 Joined: 21-November 15 From: White Plains New York Member No.: 19,387 Region Association: North East States |
What is the recommended camshaft or cylinder head upgrade??
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McMark |
Aug 7 2017, 06:31 AM
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#13
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
What is the recommended camshaft or cylinder head upgrade?? 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. |
DennisO |
Aug 7 2017, 08:22 AM
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#14
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Member Group: Members Posts: 61 Joined: 9-June 17 From: Clayton, NC Member No.: 21,162 Region Association: South East States |
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? |
echocanyons |
Aug 7 2017, 08:31 AM
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#15
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Advanced Member Group: Benefactors Posts: 2,094 Joined: 24-December 02 From: Bay Area, CA Member No.: 7 Region Association: Central California |
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? |
McMark |
Aug 7 2017, 11:17 AM
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#16
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
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. |
jim_hoyland |
Aug 7 2017, 02:49 PM
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#17
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Get that VIN ? Group: Members Posts: 9,319 Joined: 1-May 03 From: Sunset Beach, CA Member No.: 643 Region Association: Southern California |
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. |
jsaum |
Aug 7 2017, 06:49 PM
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#18
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Senior Member Group: Members Posts: 530 Joined: 12-June 07 From: Everett, WA Member No.: 7,809 Region Association: None |
Get these 96s. 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. I think I've read that the rings aren't great quality on this set. What rings would you recommend? |
DennisO |
Aug 7 2017, 09:49 PM
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#19
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Member Group: Members Posts: 61 Joined: 9-June 17 From: Clayton, NC Member No.: 21,162 Region Association: South East States |
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! |
porschetub |
Aug 7 2017, 11:30 PM
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#20
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Advanced Member Group: Members Posts: 4,706 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
Get these 96s. 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. I think I've read that the rings aren't great quality on this set. What rings would you recommend? Appears the rings are changed to Grant or similar US made...far as I can tell??? |
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