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Re expansion rates, shouldn't the block expand more than steel sleeves, MID included? An aluminium deck plate is probably not going to be 100% in the same sort of aluminium as the block but at least they will form a single piece since they are welded together.
Re expansion rates, shouldn't the block expand more than steel sleeves, MID included? An aluminium deck plate is probably not going to be 100% in the same sort of aluminium as the block but at least they will form a single piece since they are welded together.
I think the issue is that the deck plate most are using is installed with an interference fit not welded. The expansion rates of the block will be different because of the added Silicone. The Silicone slows down the rate of expansion.
The best deck plate I have seen which was on a different engine platform was a spacer for a long rod. It was machined in to the block with a flanged spacer to extend the block. Top hat cylinder liners were then installed recessed in to the deck plate. The guy is making over 1000hp on a 4cyl turbo and completely eliminated the head gasket problems he used to have.
I have had a new intake manifold made for my 16V engine. It was optimised on a flow bench with the runners ending up flowing 351 (+-5) cfm each, which I think is pretty good as I believe a bone stock 968 head flows ~300 cfm at stock intake valve lift. A second unit is under way for a friend.
Bellmouths shaping :
Powder coating :
Ready to fit (the carpet is not for sale) :
Up and running :
Originally Posted by Thom
Well, we have a jig to make further 16V intakes like mine, either with an S2 or 968 flange. Just drop me a line if you are ever interested. We just need the dimensions of the throttle body that would be used.
FWIW initially I was lent an intake using an S2 flange to get my 16V engine running and could hear some extra ticking noises with the J&S Safeguard, and that was not knock. Perhaps the turbulences caused by the step between the intake and the head caused some pre ignition. These parasitic noises are now gone with the new intake and the engine is safely tunable.
Hey Thomas,
Haven’t been here for a while… nice to see you liked the design of my intake that much, that you decided to just copy it without asking while I lend it to you :-) only a bit disappointed by your poor finish. Also cool you directly made a fixture to rebuild and sell parts with the design you stole and earn some money with it!
for all the others following this thread, here some pics when I did the first prototype in June 2019, that I lend to Thomas:
I think the issue is that the deck plate most are using is installed with an interference fit not welded. The expansion rates of the block will be different because of the added Silicone. The Silicone slows down the rate of expansion.
The best deck plate I have seen which was on a different engine platform was a spacer for a long rod. It was machined in to the block with a flanged spacer to extend the block. Top hat cylinder liners were then installed recessed in to the deck plate. The guy is making over 1000hp on a 4cyl turbo and completely eliminated the head gasket problems he used to have.
Can't quite picture what you're describing here. Don't suppose you took any pics? Also you mention that the 625+ studs require preparation and can cause more harm than good. Can you elaborate please?
Can't quite picture what you're describing here. Don't suppose you took any pics? Also you mention that the 625+ studs require preparation and can cause more harm than good. Can you elaborate please?
On the engine I described they raised the deck height using a plate which at the same time closed the deck. The plate was recessed around the bores and a top hat liner installed locking the bores to the plate. In this case a longer conrod was used to get a better rod ratio for higher rpm. I don’t have pics but it was a Cosworth drag car here in Australia.
I believe to go the next level in hp you need to come back to the 2.5 crankshaft and turn the rpm’s. Don’t get me wrong the 3.0 crankshaft makes for an ideal engine within the stock rpm limit. As you know a 968 head, vario cam and stock cams will give a broad, flat torque curve and 600hp. I have a build of my own which will be exactly this. But to go 800-1000hp the engine is going to need rpm and the long stroke just doesn’t work. The rod ratio of the 3.0 doesn’t lend itself to rpm’s, 2nd order vibrations are also magnified by the longer stroke. In addition by having a larger crank pin offset the crankshaft loses rigidity and causes crankshaft flex or whip. This is something the Nissan RB26/RB30 guys as well as the Mitsubishi 4g’s are seeing, they all go back to the shorter stroke crank for big hp. I remember seeing the Revline 968, it cracked the block at the main bearings, I believe this was crankshaft flex. I think he had also increased the stroke of the 3.0 using an offset grind which would have made things worse.
The reliability issue in relation to the 625+ comes from the threads and not tearing them out of the block at 130lbf of torque. I keep hearing over and over again peoples success with head gaskets coming from the gasket design and not a higher torque. The current recipe for success seams to be a copper head gasket with a fire ring and opposing receiver groove. I would still be using ARP or similar and torquing to 90-100 ftlbs.
There is one other idea that may work that I haven’t measured out but are eyeball close enough to pursue further. This is a long bolt design (Cosworth YB) basically the head bolt continues through the block and secures the main bearing girdle as well. This eliminates any reliance on the blocks aluminium threads as it is just one long bolt from top to bottom.
I will add there isn’t too many people modifying the 944/968 to this level so I get a lot of my knowledge from guys who are modifying different platforms. Not surprisingly all the highly modified platforms regardless of manufacturer are doing the same things as each other anyway.
Ahh...gotcha. Sounds like an interesting approach. Wonder how thick that plate is? Wouldn't want to raise the head too much if you can avoid it but sounds like it's working for them.
Yes, I've also got a stroker crank. Can't believe that it caused the catastrophic failure on the last engine so soon though? If it was prone to doing it immediately then it would have showed on the dyno I'd have thought.
I've got those studs that you know about. Also bought the recommended serts. Apparently these have been tested to 160lbs. I'm certainly not going there.
The long bolt design has been mentioned in the past. Also separating the head and the block cooling paths. I like that idea. If I were going to keep the car long term I'd opt for that modification.
Or a billet block...or a different engine platform...yada yada...
Haven’t been here for a while… nice to see you liked the design of my intake that much, that you decided to just copy it without asking while I lend it to you :-) only a bit disappointed by your poor finish. Also cool you directly made a fixture to rebuild and sell parts with the design you stole and earn some money with it!
I guess you know a thing or two about making money by stealing someone else's design, like making a 100% profit on the back of Porsche themselves with each of the 968 turbo RS strut brace replica you sell.
Anyway I won't go further into the reasons why I ended up having an intake made for me and for one of my friends, as I have far better things to do and this would require revealing some nasty personal details about a petty hillbilly who stabbed me in the back, and this is saying enough already, as much as the post quoted above itself already suggests.
Haven’t been here for a while… nice to see you liked the design of my intake that much, that you decided to just copy it without asking while I lend it to you :-) only a bit disappointed by your poor finish. Also cool you directly made a fixture to rebuild and sell parts with the design you stole and earn some money with it!
for all the others following this thread, here some pics when I did the first prototype in June 2019, that I lend to Thomas:
To be fair, that "design" isn't very unique, been making intakes like that in Scandinavia since The 90's.
I guess you know a thing or two about making money by stealing someone else's design, like making a 100% profit on the back of Porsche themselves with each of the 968 turbo RS strut brace replica you sell.
Anyway I won't go further into the reasons why I ended up having an intake made for me and for one of my friends, as I have far better things to do and this would require revealing some nasty personal details about a petty hillbilly who stabbed me in the back, and this is saying enough already, as much as the post quoted above itself already suggests.
stabbed you in the back by doing 80% of the mechanical work to get your engine in and running for free, using my equipment and possibilities, close to the strutbrace you were lucky to get for cheap… so I have to be really thankful to have the huge pleasure to serve the outstanding personality you are
Last edited by 944er-teile.de; 12-01-2022 at 07:45 PM.
stabbed you in the back by doing 80% of the mechanical work to get your engine in and running for free, using my equipment and possibilities, close to the strutbrace you were lucky to get for cheap… so I have to be really thankful to have the huge pleasure to serve the outstanding personality you are
It seems you didn't mind the company of my "outstanding personality" over the 100s of hours I spent assisting you, either at your workshop to wrench on your projects and customer cars or more generally as a helping hand for whichever work in your house.
It seems now that I should have counted all of the time I spent for your own personal benefits, but I did not as this is a rude way to proceed between friends, something that apparently still doesn't occur to you and might explain why you don't seem to have genuine, disinterested friends but mere buddies instead.
It is a bit curious to see how you suddenly come on here and try again to **** all over my shoes publicly a year and a half after you threw your toys out of your pram and started to blackmail me, which is what pushed me in the first place to find someone else to build an intake to get my engine running again, but I suppose you have been running out of "friends" to blame and abuse lately.
You can consider yourself lucky that we have a common friend who calmed me down somehow and went out of his way to help me in view of your miserable and embarassing behaviour, as I am no more in the mood to drive over to your place to give you the 1000s slaps in the face that your parents apparently never gave you, the result being a narcissic perv who thinks he is clever when he is just an arrogant hillbilly with a bag full of tricks, and some really nasty ones.
Incidentally this is the impression I had of you the very first time I came across you at a car meet a couple of years before moving not too far from your place and starting hanging out with you... I guess I should have stayed with my initial impression rather than try to see beyond your unlikeable personality (after all we all have our own backgrounds) and focus on the factual car stuff instead.
In the name of what once seemed to me a genuine friendship, even if it was project-based and that I thought would carry on for a long time despite our cultural differences, at this stage I can only feel sorry for you and say farewell and good luck.
Apologies to other readers for all this, but to hear some guy claiming I had "stolen" his intake design which he made by copying other folks' intakes looking at photos posted on here, using sheets and tubes of aluminium I had paid for, whilst besides he stole nothing less than a Porsche design to make good money with, is something that just cannot get by in a breeze.
ETA : I have asked the mods to remove all the posts, including this one, that don't belong on here.
This is the place to post about your 3 liter (or otherwise big) 944/968 turbo motor, and to keep a list of the running motors/projects as a reference for aspiring 3 liter builders. Feel free to ask questions and include details about your motor in your post -- with extra points for pictures . If you have a running motor or project for the lists below, be sure to post or PM me a one-line entry I can copy into the list below.
Back by popular demand (well, demand anyway), below is the full list of running motors, starting in 2008, with the latest additions added and hopefully growing at the bottom:
00. ModdedEverything951S, 3.1, Darton Wet, 106, 88, Wossner/Pauter, 2.7, TecGT, VR Cam, VR5 1. Duke, 3.0, Alusil, 104.5, 88, mod 968 variocam, Link G3+, Garrett GT3582R, builder: Duke 514/450 at wheels 2. Diver944, 3.2, Nikasil, 108, 88, JE, 2.7, Vittese, stock, Garret hybrid, 393/480 3. John Torgersen, 3.0,Steel, 104, 88, JE, 2.7, Motec M4 Pro,K27/8, 383HP@15 4. John Torgersen, 3.0,Steel, 104, 88, JE, 2.5, LR/Stg3 MAF, T04 Hybrid, 366HP@15 5. Targa72e, 3.0, Alusil, 104, 968 mod, 968 head, Motronic, T04E, cam and hp n/a 6. Mike O, 3.0, Alusil, 104.5, 88, HMR, 16v, TECgt, HMR turbo, cam and HP n/a 7. SoloRacer, 3.0, 16V, Motec 8. Kasturbo, 3.0, Alusil, 104.5, 88, Mahle/Andial, 2.7, LRS75, VR turbo, Webcam, HP n/a 9. George D 3.1, 105 Nicom, 88.6, Custom Ross Racing, TECGT, 951 cam, 540hp@23psi 10. Arto951 3.0, Alusil, 104.5, 88, Mahle/Andial, 2.7, Holset Turbo, Tatech EMS, dBilas cam 11. Pete96zhn, 3.0 darton mid, Wossner pistons, 944 head, VR EMS, Holset turbo, Standard cam 12. Phlip, 3.0 Darton Dry, 105.5JE pistons, S2 16v head, Autronic SM2 EMS, T3 turbo (R.I.P. 3/15/09) 13. Ski, 2.8, Alusil, 100.5 Ski/Mahle pistons, 88 stroke, 951 head, LR EMS 14. TurboTommy. 3.0, Alusil, 968 mod pistons, 2.7 head, VR EMS, VR turbo, JME cam 15. Weston D., 3.0, Alusil, 968 pistons, 951 head, LR EMS, rest n/a 16. Jason@paragon, factory 968 turbo. Nuff said. 17. Boost Feen, 3.0, Alusil, Tom C/Arias Pistons, 2.7 head, Motronic, LR61 turbo, 951 cam, hp n/a 18. Joel8005 3.2, bore material n/a, JE pistons, 2.7 head, LR EMS, turbo/cam/hp n/a 19. David Floyd, 106mm SFR bores, JE pistons, 951 head, VR EMS, VR4 turbo, cam and hp n/a 20. Jason Judd, 3.0 (?), Mahle pistons, Carillo rods, head n/a, Lindsey Super 75, Autronic 21. ShApe, 3.0, Alusil?, Pauter, JE, LR solid lifter conversion, 2.7 head, Web cam, HP n/a 22. CMF, 3.0, Alusil, PO rods, 88, 951 head mod, VEMS 3.3, webcam, Garrett GT3582, 421.8hp@16psi 23. Corleone, 3.0, Darton MID, JE, 951 head, Link G2, JME solid cam, 449hp/560hp@1/1.25 bar 24. Turbo-Uli, 3.0, 104 Alusil, 88 crank, 16v head, rest n/a 25. Nick_968, 3.0, Alusil, 104, Mahle/Andial, 2.7 head, Motec, VR5 turbo, JME cam, 370/355 @? 26. jm964cab 3.0, Alusil?, JE pistons, KKK28/9, Mafterbuner, APE MAF, cam and hp n/a 27. zagaone, 3.4, 16v. 108mm bore/93mm stroke; electromotive; 493rwhp/486tq @1bar. 28. 968TurboS, 3.0 Nikasil block, Carillo rods, JME 2.7 head, GT3076R 29. Josh B, 3.0, 8V, Mahle, VR EMS, Wasted Spark, VR5Turbo, Pauter, Webcam, LR Solid cam 30. Miles968, 3.0, 16V, Mahle Pistons, PH Custom Rods, PH K29 Turbo 31. tone3721, 3.0, Alusil, 104mm, 88, mahle, 2.7, LR, stock(951), VR3 32. 420WHP944, 2.8, 8V, Carillo Rods, Mahle Pistons, Kokeln Club Turbo, MAP Sensor, 422bhp @1.2 bar 33. dand86951, 104.75 alusil, 88 crank, JE coated, 2.7 head, TEC3, K27/8, Carillo Rods 34. tomjshore, holy grail motor -- factory 3 liter turbo 35. Thom 104.5 M/Andial, 88mm, '89 8v, carrillos, GTX3076R, PT Vi-Pec/J&S, SFR I/C, LR 3", KEP2/930 36. A.Anon, 3.2, Nikasil 108 bore, 88 crank, JE pistons, Carrillos, 2.7 8v, VR Maf, 3" exhaust, SPS turbo 37. Fortysixandtwo, 3.0, 968 head, 968 block, Tec-3, Under Pressure Performance turbo 38. apitts73, Lindsay built 3L with everything 39. mikes3.0cabturbo 3.0 16v alusil, 104.5 wossner pistons/wossner rods, 60-1, 4424EMS2. 40. Tom M'Guinn, 3.0, Alusil, 104.5, 88, Mahle/Andial, 2.7, VR, Gomes, VR5, 498/503 (35k miles and going as of 9/20) 41. Urs, 3.0, Carillo, Walh/Mahle, 7mm valve guides, K27 42. JET951, S2 engine, wossner 8.0:1 CR 16V, SFR intake, vitesse stage 5 43. ninfiveone, 3.0 MID, Wossner Pistons, Haltech, VR 8V Sledge head, cam, 415 rwhp @ 20psi 44. tkgb, 104.5 S2, 88 stroke, wössner piston/rods, LR super 75, motronic, 4-1 headers, 408 RWHP at 1.2bar 45. ChrisJ951, S2, Wossner Pistons, Carillos, Spec S3 hybrid, LR Super 65, LR stage 2 head, Webcam 46. SSI Performance, 105S2/88 Nikasil, JE, 2.7 ported , Wossner Rods, Vi-PEC, more, 402/443@17 dynapac 47. 951_VAB, 104mm JE, Carillo, 2.7 worked head, JME cam, LR 75/10/P, LR MAF, 951Max chips 48. Thingo, 3.0, 8 valve, Arrows/Wossner, Twin scroll FP HTA GT35 twin tial WG, Motec ecu,sdl,cdi 49. blown 944, 2.85 custom stroker, JE, Eagle, sleeved/filled, Holset HX40/35 S w/Garrett hotside, Rogue tune 50. Grushy, Lindsey-Built 3.0 JE pistons, alusil, solid lifters... 51. Bri Bro, New factory Block, 100.5, 88, Mahle, Carrillo, Vflex+ E85, VR4, South Bend, LR intake, Ported head 52. Rluciano 104/88, Mahle/CEP pistons, Carrillo, 2.7 by Neil H., GT3582R, Link G4, mystery cam 53. Refresh951, 3.12L, Hybrid Stroker, 8V, JE, Eagle, sleeved/filled, 102, 95, GT3582R, Rogue tuned, 535/487 54. blown 944, 3.0 custom stroker, 105.5, FRF Deckplate, Eagle, sleeved, Holset HX40, 95One Intake, Rogue tune 55. Jon951, 3.0L, 104mm, 16V, JE, Crower Rods, Revline Racing Intake, VR S5 Turbo, Rogue, 500 rwhp at 15.5 psi
56.. Player0, JE/Molnar 3.0, darton dry, web274, 2.7 8v, gtx3582v2, haltech #958
57. gpr8er, 2.7 block and 2.7 head, turbo valves,S2 crank knifed, 104.5 Andial/Mahle,GT 3582r vband.VEMS
The cars on this list are pretty incredible!
Up to 170mph, I beleive a 924 or 944 with 450 whp will be as quick as a 2021 992 Turbo S as long as :
it weighs 2750lbs or less and is using a 968 gearbox with a 25 inch tire diameter and you can shift gears in 0.3 seconds compared to the PDKs 0.1 second
There is one other idea that may work that I haven’t measured out but are eyeball close enough to pursue further. This is a long bolt design (Cosworth YB) basically the head bolt continues through the block and secures the main bearing girdle as well. This eliminates any reliance on the blocks aluminium threads as it is just one long bolt from top to bottom.
I owned a Sierra Cosworth with the YB engine for years. It had a iron Pinto based block, using studs screwed into the block and nuts to fasten the head. And bolts to secure the main bearing caps.
I owned a Sierra Cosworth with the YB engine for years. It had a iron Pinto based block, using studs screwed into the block and nuts to fasten the head. And bolts to secure the main bearing caps.
Not a stock YB installation but in the never ending quest for more hp the “through stud” design was developed. First was the “long stud” which is similar to our engines from the factory, then came the through stud. The issues the YB encountered are very similar to what we are seeing.
There’s a couple of ways to correct the problems but with very little investment in our platform we are limited in options. Ultimately a stronger stiffer modern crankshaft would be ideal, this would fix the flexing at the source. Second to that you can try and bolt it down and secure it better to the block but without a through stud setup you are limited by block strength and bearing longevity.
This is why I believe the 2.5 crank is the ideal option for an all out approach. The shorter stroke is a benefit of its own in terms of rod ratio and amplitude of flexing motion. But in addition it has more overlap between the webs creating a stiffer crank.
08-28-2022, 04:16 PM
