Could this work?, 2056 engine combo ?'s |
|
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. |
|
Could this work?, 2056 engine combo ?'s |
ottox914 |
Nov 23 2016, 02:07 PM
Post
#1
|
The glory that once was. Group: Members Posts: 1,302 Joined: 15-December 03 From: Mahtomedi, MN Member No.: 1,438 Region Association: Upper MidWest |
So here's my long sad story. The turbo motor dies several yrs ago, due to a missed shift at lots of boost and rpm's. I bought a recently re-built motor from a forum member to replace it, thinking this was faster and easier than re-building the turbo motor. Lost a year to a new job, selling an house, buying a house, moving to a new state, bring my retired dad along and getting him re-set in a new environment. Put the re-built motor in this past summer. It kept blowing up. Pulled it and fixed it all summer. Kept the seller updated as to my problems with the "good" motor. Called the seller this fall, who graciously agreed to refund full purchase price.
So now I again have a motorless 914. Trying to figure out an N/A build that uses most of the parts in my shed to keep $$$ down. I have the pieces in my stash to build the following: 2 good cases to choose from, 2.0 crank and rods, some good iron cylinders to overbore to 96, (would need to buy some KB's to fill them) some heads that Len did that are 40 x 36, (about 75% I/E ratio) that he says will flow about 175 cfm at 50% lift. They have a 50.4cc chamber. So these, with some flat top KB's would yield about 10.5:1 with .040 deck. 2x valve springs, Len is comfortable with this head to 7k rpm if I would need to go there. I have the ITB's and SDS efi to run it all, and as the injectors were sized to support the turbo motor, I expect I have enough headroom to run some E85 "corn" fuel to handle the CR. Should also hold detonation at bay, and engine should run cooler on corn. Not a bad thing for aircooled motors. Kerry hunter exhaust to finish things off. The wild card is the cam. The cam I had in the turbo motor is still good, not damaged by the over rev. Its ground on a 110 center, has a lift of .500, and is a split duration of 276I/284E, with duration at .050 of 240/249. When researching cams for the turbo motor, seems lots of folks say a factory cam N/A is a pretty good starting point for a turbo cam. When I go to the Web Cam page for the 914, what I got is bigger than an 86, the "street" cam, but not as wild as 86a or 494. What think the collective? Will the flow of the head, small-ish intake valve, and big lift of the cam play well as a team? I expect to get alot of "its all in the combo" remarks, but with as much as is known about what I have to build with, and the cam being the big ?, looking for opinions from those more cam-educated than myself on options to use what I got or not. |
ottox914 |
Jun 15 2018, 11:12 AM
Post
#2
|
The glory that once was. Group: Members Posts: 1,302 Joined: 15-December 03 From: Mahtomedi, MN Member No.: 1,438 Region Association: Upper MidWest |
Well, now we got to see how this works out. Motor is built as outlined above, but with 9.5:1 cr and running BP 93 rather than corn. After many long discussions with my good friend and owner of Complete Tuning Solutions we decided pump would do for now. I have plenty of injector if I wanted to try E85 at a later date.
We have 4 hrs of dyno time booked this afternoon, 2 for the 914 and 2 for the CTS vette. The afternoon will be brutal, on cars and bodies. There is a heat advisory in our area till 7pm tonight. But the time is booked, we both took time off work, so here we go. Lots of fans, cool down between runs, watch the oil temps and pressures. I have CHT and EGT gauges to watch also. The bonus is that if we can safely get to the best the motor has to offer in these conditions the car should be understressed in most all others. No idea how many runs we might get. We have been working on a good road tune for the last year, so after a baseline run we’ll see where the maps might be improved. The SDS has a nice feature to dump more fuel in if you go way to lean. Hopefully with the heat and stress of the runs we never need that feature. If time and energy permit I have 3 different sets of air horns to try. It would be cool to see how HP/TQ are affected by the different lengths. Of course there will be a full report to follow. Still on the rollers. Place your bets on what it makes. |
Lo-Fi Version | Time is now: 18th May 2024 - 08:23 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 ... |