![]() |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
![]() |
ThinAir |
![]()
Post
#1
|
Best friends ![]() ![]() ![]() ![]() Group: Members Posts: 2,546 Joined: 4-February 03 From: Flagstaff, AZ Member No.: 231 Region Association: Southwest Region ![]() ![]() |
This started out as this topic: http://www.914world.com/bbs2/index.php?act=...=ST&f=2&t=28067
It seemed like a good idea to start a new thread with different subject. The 2.0L engine I'm building is using stock crank & rods with stock size (94mm) Euro flat top pistons. My understanding from other topics is that when you build such an engine you get slightly higher compression than stock because of the flat top piston, but you basically don't need to change anything else. When I put the first piston & cylinder in place I used the .007" barrel gasket that was included with the overhaul gasket set. I measured the distance from the top of the piston at TDC to the top of the cylinder at .022" I don't have the actualy head cc measurement, but the paperwork for getting my heads done says they were cut .005". I don't know for sure if that is just this time or if the final cut is .005 including any cuts done during previous rebuilds. Using the math formulas and various calculators mentioned in the previous topic, I figure that if I assemble the engine this way I'll end up with a compression ratio of about 1:8.2 or 1:8.4 This engine will use the stock D-jet FI. So my question is: is it ok to assemble the engine with what I have or is this compression too high? If it's too high, what should I be shooting for with Euro flat top pistons? If I need different barrel spacers to reduce the compression, it's fine with me, but I don't want to just pick some number out of a hat or build it this way without knowing that it's ok. |
![]() ![]() |
Jake Raby |
![]()
Post
#2
|
Engine Surgeon ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States ![]() |
I am almost finished with my head cc kit for the TIV engine.... I'll add them to the store ASAP. They are very nice.
Head ccs being measured accurately is important. There is no "standard" and no margin for error. Heads can vary in ccs so each chamber must be check and they may need to be balanced if you really want to do it right. I have all the cylinder shims, even very odd sizes. |
![]() ![]() |
![]() |
Lo-Fi Version | Time is now: 28th June 2024 - 10:34 PM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |