Pete I never heard of Porsche running the Inline 4 to anywhere near 500hp but of course I'm sure they might have tried it in testing. Remember that the Porsche 934 had less than 450bhp. I've never seen one of the famed LeMans Rods but I'd be betting that it wouldn't resemble a stock rod 100%. I've got nothing against the stock rods by the way. I've ran them on motors up to approx 30psi (by accident) and run them regularly up to 23psi and not had a problem. If I was building a new motor though, I'd be looking at other options just the same. Of course it's possible to throw any rod with the wrong tune or assembly. If that happens though it won't be the worst of the damage! With your Vitesse software he's generally pretty careful/conservative at the limit. Otherwise LINK / Vipec (check TTM's setup) or Motec would be my recommendation.
Building a 400bhp+ 2.5 ltr 944 Turbo
- Thread starter PSH
- Start date
Hi Patrick from what I've read Porsche certainly wound the Inline 4 up to 1.5 bar achieving 500bhp, then reduced it to 1.1bar 420 bhp for racing. of course you could look at the 944 GTR with over 600bhp, some say +700bhp but that has little resemblance to a stock 944 engine although still an Inline 4 non the less and certainly has some of the standard cars castings, block, cam tower etc, not sure on internals but very much doubt they are Porsche as it was a special built for the Americans. Anyway that car is a world away from what I'm building, I guess over time things get forgotten including how much Porsche associated the then new 944 turbo with it's Le Man car the 924 GTP also known as the 944LM. However the info is out there if you look, one such quote is: "The similarities between the GTP and the 944 Turbo are therefore quite apparent. As if to draw a more concrete connection, Porsche made notable associations. Interestingly, the cam cover of the GTP’s engine featured beveled text reading “944 Le Mansâ€, a hint at the car’s prototype status. In fact, some sources even refer to the car as the 944 GTP. Even Porsche commented in an advertisement for the 944 Turbo in 1986 that “efore we start production on a car, it’s already finishedâ€, obviously referring to the similarities between the retired GTP and the production 944 Turbo." There are others but I'm getting a little off topic..
Regarding EMS/ not decided on this yet and as stated it's part of stage 2 so plenty of time to make a decision . Pete
Not had long for the engine today ( working on pond) but got one of the seized studs out, for those who are not sure about doing this it isn't too difficult, just take your time. First centre punch the end of the stud as close to centre as possible, drill out the stud starting with a small drill bit up to the correct size ( I started with 2mm up to 5mm) as if you were drilling a tapping hole. Use slow speed High Torque setting with plenty of cutting fluid. If by chance your off centre all is not lost just be extra careful and only drill out close to thread, you can either then use an easy out ( i don't like these, too easy to break) or manually grind away ( small dremel will do)until the hole is more central and then continue with correct drill size. Others may use a different approach, this one works for me, finally I re-tap the hole with a HSS tap, don't use the cheaper carbon type, although they are very sharp they are also very brittle and more likely to snap which is a possibility when working by hand at an angle. hole at 3mm size
final 5mm size drill, note the tape used as a guide to stop before drilling too deep. It's interesting to note that here in my eyes is a design flaw and why the studs were so corroded in the first place. The corroded studs ,all to a varying degree progress into the water way, some clearly go right through whereas others just barely break into the inner surface. I haven't yet checked with the Porsche manual for this stage but either the studs are left alone to their own devices and hence have corroded due to entering the water way, they were originally sealed which has failed due to age or if they should indeed be sealed the water pump when replaced previously wasn't done properly and studs were inserted dry. Knowing which independent did this work and the problems they have caused me before this wouldn't surprise me at all but i digress. What ever the facts are surely the use of stainless studs here would have avoided this extra work now?
finally after re-tapping the hole 6mm I replaced one of the old studs to check the depth was sufficient, I also inserted a short 6mm bolt and torqued it up to it's 6lb setting to ensure the thread is still up to the job. don't get me wrong this is overkill but it's the way I work so forgive me for taking extra care.
Needless to say I won't be covering all such problems but thought it worth recording this to help others, if everything had gone badly wrong I do have heli-coil kits but prefer to try and avoid using them if at all possible, the important thing is that the hole remains true to it's original position. Pete
George Elliott
New member
Pete you do a better job of stud extraction than our local dentist...well done. just on that, I have found MIG welding an oversize hex nut to the stub can sometimes persuade them to release, the objective is to get as much heat as possible down the stud. Maybe this releases the sealant from the factory, or maybe they loctite them, I don't know. Just on the Rods point, my engine is a perfect bore block with early OE rods. Its not a serious power unit, but slightly improved all the same. Simon at SPS was very confident these rods were good. I accepted his view for two reasons, one you do have to draw the line somewhere, and two - there's not much point in using flashy 1000bhp rods in an engine with half that power. There will be those who take the while your at it viewpoint, and for sure none of us want to risk putting a leg out of bed, but there is no unbreakable rod either. The crank weighs near 30kg I understand, so a few grams of extra rod weight is unlikely to hinder the unit, but the balance is key as always. It's not going to be a Vtec Honda after all. Have you considered a steam vent kit off the back of the head? Its not big cost, and analysis of engine failures is often close to this area, just a thought as you have the head off. Thanks for all the info. Good luck with the project George 944t
Hi George As the saying goes great minds think alike.. I did try welding nuts onto the studs as you suggest after failing to move them with Molgrips etc, I had got a little movement with the grips but alas they were just too tight. Unfortunately the welding weakened the steel which I was half expecting as the studs were in a very bad shape, you'll probably be able to see in one of the pictures just how much of the thread had been eaten away so I wasn't surprised they gave up. Saving weight on the crank and it's components will give a little more power and and a quicker revving engine but as you say 'were do you draw the line' Technically the crank is already a little lighter due to being reground but this won't make much if any difference, pistons will be lighter but the real saving will be from using a crank scraper which I've read will save around 7lb's in rotational mass on the crank. More importantly it will greatly reduce the build up of entrained air bubbles within the rotating mass which has been known to cause No.2 rod bearing to fail. Add to that the lightweight flywheel and things are certainly moving in the right direction. The steam vent kit is an interesting one and something I'm considering especially as I have had two gaskets and a valve fail all around No.4 exactly where the air pocket that the steam vent kit is supposed to reduce is know to occur. So there's a big possibility that I'll go this route although I'm still researching what other ideas may be out there. Thanks for the input George, the more the better..
PeteEx Skyline
New member
Great piccy's Pete and, great input from everyone so far! I am learning a lot from this thread. Pete []
]
thanks for the kind words everyone... Ok so regarding
Head = 55cc (standard approx) Piston volume dish= 26.0cc 101x0.70mm gasket = 5.6cc (aprox) CChamber = 55 + 5.6 +26(piston dish) = 86.6cc Therefore: 632.05 +86.6 ) / 86.6 = CR 8.26:1(using a 0.70mm gasket) Now this is using the thinnest available Cometic gasket , so the CR will only get less with the other gaskets available to me, add to this the possible larger bore of 103mm and I'll have no problem maintaining 8:1 or less. So the question is gasket bore size, 100.5 vs 103mm, the way I look at it having a gasket with a smaller bore than the cylinder is a no go (unless someone knows better?) so I guess it will be the 103mm Anyway that's my head fried enough for tonight.... On a good note i got the two remaining water pump studs out tonight, just the 10mm mounting stud to go and that's going to be a real bitch All opinions very welcome as usual Pete
Hi TTM Well I had a few minutes today to look closer at the CR possibilities, I've used the standard head cc for the calculation as I don't know what my Lindsey stage2 head is and it will be some time before I get around to stripping the head and polishing ready to measure it's cc, plus the head needs machining first, due to the resulting damage sustained in No.2 chamber from the damaged iridium plug mentioned previously and thus will get deeeper, although only by a very small amount. Also another consideration is gasket bore size, unless someone knows better the closest that i can find to my new 101 bore is 100.5 or 103mm so I'm thinking that 103mm may be for me. Also the choice of Cometic gasket thicknesses for the 944 is massive, from 0.68-2.03mm so I have a little to play with here. For ease I've used a bore of 101mm for the calculation on the gasket, using a thickness of 0.70mm so what do we have? Displacement = 101 x 78.90 (10,1 x 10,1 x 3,1412 / 4 * 7,89) = 632.05cc ( considering deck as 0) per cylinder with a total displacement of 2,528.2cc... nice..
Head = 55cc (standard approx) Piston volume dish= 26.0cc 101x0.70mm gasket = 5.6cc (aprox) CChamber = 55 + 5.6 +26(piston dish) = 86.6cc Therefore: 632.05 +86.6 ) / 86.6 = CR 8.26:1(using a 0.70mm gasket) Now this is using the thinnest available Cometic gasket , so the CR will only get less with the other gaskets available to me, add to this the possible larger bore of 103mm and I'll have no problem maintaining 8:1 or less. So the question is gasket bore size, 100.5 vs 103mm, the way I look at it having a gasket with a smaller bore than the cylinder is a no go (unless someone knows better?) so I guess it will be the 103mm Anyway that's my head fried enough for tonight.... On a good note i got the two remaining water pump studs out tonight, just the 10mm mounting stud to go and that's going to be a real bitch All opinions very welcome as usual PeteGeorge Elliott
New member
Pye = 3.14159 = Ans 632.13cc [8|] For this level of performance it may just matter...[
] George 944t
hahahahahah... you just made my day, nearly fell off my chair.....I think I meant to say 3.142, not sure where the extra 1 came from but if we want to be really accurate although pye is infinite you could use.............................. 3.14159265358979323846264338327950288419… 0348 2534 2117 0679 8214 8086 5132 8230 6647 0938 4460 9550 5822 3172 5359 4081 2848 1117 4502 8410 2701 9385 2110 5559 6446 2294 8954 9303 8196 4428 8109 7566 5933 4461 2847 5648 2337 8678 3165 2712 0190 9145 6485 6692 3460 3486 1045 4326 6482 1339 3607 2602 4914 1273 7245 8700 6606 3155 8817 4881 5209 2096 2829 2540 9171 5364 3678 9259 0360 0113 3053 0548 8204 6652 1384 1469 5194 1511 6094 3305 7270 3657 5959 1953 0921 8611 7381 9326 1179 3105 1185 4807 4462 3799 6274 9567 3518 8575 2724 8912 2793 8183 0119 4912 9833 6733 6244 0656 6430 8602 1394 9463 9522 4737 1907 0217 9860 9437 0277 0539 2171 7629 3176 7523 8467 4818 4676 6940 5132 0005 6812 7145 2635 6082 7785 7713 4275 7789 6091 7363 7178 7214 6844 0901 2249 5343 0146 5495 8537 1050 7922 7968 9258 9235 4201 9956 1121 2902 1960 8640 3441 8159 8136 2977 4771 3099 6051 8707 2113 4999 9998 3729 7804 9951 0597 3173 2816 0963 1859 5024 4594 5534 6908 3026 4252 2308 2533 4468 5035 2619 3118 8171 0100 0313 7838 7528 8658 7533 2083 8142 0617 1776 6914 7303 5982 5349 0428 7554 6873 1159 5628 6388 2353 7875 9375 1957 7818 5778 0532 1712 2680 6613 0019 2787 6611 1959 0921 6420 1989 3809 5257 2010 6548 5863 2788 6593 6153 3818 2796 8230 3019 5203 5301 8529 6899 5773 6225 9941 3891 2497 2177 5283 4791 3151 5574 8572 4245 4150 6959 5082 9533 1168 6172 7855 8890 7509 8381 7546 3746 4939 3192 5506 0400 9277 0167 1139 0098 4882 4012 8583 6160 3563 7076 6010 4710 1819 4295 5596 1989 4676 7837 4494 4825 5379 7747 2684 7104 0475 3464 6208 0466 8425 9069 4912 9331 3677 0289 8915 2104 7521 6205 6966 0240 5803 8150 1935 1125 3382 4300 3558 7640 2474 9647 3263 9141 9927 2604 2699 2279 6782 3547 8163 6009 3417 2164 1219 9245 8631 5030 2861 8297 4555 7067 4983 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4469 5848 6538 3673 6222 6260 9912 4608 0512 4388 4390 4512 4413 6549 7627 8079 7715 6914 3599 7700 1296 1608 9441 6948 6855 5848 4063 5342 2072 2258 2848 8648 1584 5602 8506 0168 4273 9452 2674 6767 8895 2521 3852 2549 9546 6672 7823 9864 5659 6116 3548 8623 0577 4564 9803 5593 6345 6817 4324 1125 1507 6069 4794 5109 6596 0940 2522 8879 7108 9314 5669 1368 6722 8748 9405 6010 1503 3086 1792 8680 9208 7476 0917 8249 3858 9009 7149 0967 5985 2613 6554 9781 8931 2978 4821 6829 9894 8722 6588 0485 7564 0142 7047 7555 1323 7964 1451 5237 4623 4364 5428 5844 4795 2658 6782 1051 1413 5473 5739 5231 1342 7166 1021 3596 9536 2314 4295 2484 9371 8711 0145 7654 0359 0279 9344 0374 2007 3105 7853 9062 1983 8744 7808 4784 8968 3321 4457 1386 8751 9435 0643 0218 4531 9104 8481 0053 7061 4680 6749 1927 8191 1979 3995 2061 4196 6342 8754 4406 4374 5123 7181 9217 9998 3910 1591 9561 8146 7514 2691 2397 4894 0907 1864 9423 1961 5679 4520 8095 1465 5022 5231 6038 8193 0142 0937 6213 7855 9566 3893 7787 0830 3906 9792 0773 4672 2182 5625 9966 1501 4215 0306 8038 4477 3454 9202 6054 1466 5925 2014 9744 2850 7325 1866 6002 1324 3408 8190 7104 8633 1734 6496 5145 3905 7962 6856 1005 5081 0665 8796 9981 6357 4736 3840 5257 1459 1028 9706 4140 1109 7120 6280 4390 3975 9515 6771 5770 0420 3378 6993 6007 2305 5876 3176 3594 2187 3125 1471 2053 2928 1918 2618 6125 8673 2157 9198 4148 4882 9164 4706 0957 5270 6957 2209 1756 7116 7229 1098 1690 9152 8017 3506 7127 4858 3222 8718 3520 9353 9657 2512 1083 5791 5136 9882 0914 4421 0067 5103 3467 1103 1412 6711 1369 9086 5851 6398 3150 1970 1651 5116 8517 1437 6576 1835 1556 5088 4909 9898 5998 2387 3455 2833 1635 5076 4791 8535 8932 2618 5489 6321 3293 3089 8570 6420 4675 2590 7091 5481 4165 4985 9461 6371 8027 0981 9943 0992 4488 9575 7128 2890 5923 2332 6097 2997 1208 4433 5732 6548 9382 3911 9325 9746 3667 3058 3604 1428 1388 3032 0382 4903 7589 8524 3744 1702 9132 7656 1809 3773 4440 3070 7469 2112 0191 3020 3303 8019 7621 1011 0044 9293 2151 6084 2444 8596 3766 9838 9522 8684 7831 2355 2658 2131 4495 7685 7262 4334 4189 3039 6864 2624 3410 7732 2697 8028 0731 8915 4411 0104 4682 3252 7162 0105 2652 2721 1166 0396 6655 7309 2547 1105 5785 3763 4668 2065 3109 8965 2691 8620 5647 6931 2570 5863 5662 0185 5810 0729 3606 5987 6486 1179 1045 3348 8503 4611 3657 6867 5324 9441 6680 3962 6579 7877 1855 6084 5529 6541 2665 4085 3061 4344 4318 5867 6975 1456 6140 6800 7002 3787 7659 1344 0171 2749 4704 2056 2230 5389 9456 1314 0711 2700 0407 8547 3326 9939 0814 5466 4645 8807 9727 0826 6830 6343 2858 7856 9830 5235 8089 3306 5757 4067 9545 7163 7752 5420 2114 9557 6158 1400 2501 2622 8594 1302 1647 1550 9792 5923 0990 7965 4737 6125 5176 5675 1357 5178 2966 6454 7791 7450 1129 9614 8903 0463 9947 1329 6210 7340 4375 1895 7359 6145 8901 9389 7131 1179 0429 7828 5647 5032 0319 8691 5140 2870 8085 9904 8010 9412 1472 2131 7947 6477 7262 2414 2548 5454 0332 1571 8530 6142 2881 3758 5043 0633 2175 1829 7986 6223 7172 1591 6077 1669 2547 4873 8986 6549 4945 0114 6540 6284 3366 3937 9003 9769 2656 7214 6385 3067 3609 6571 2091 8076 3832 7166 4162 7488 8800 7869 2560 2902 2847 2104 0317 2118 6082 0419 0004 2296 6171 1963 7792 1337 5751 1495 9501 5660 4963 1862 9472 6547 3642 5230 8177 0367 5159 0673 5023 5072 8354 0567 0403 8674 3513 6222 2477 1589 1504 9530 9844 4893 3309 6340 8780 7693 2599 3978 0541 9341 4473 7744 1842 6312 9860 8099 8886 8741 3260 4721 5695 1623 9658 6457 3021 6315 9819 3195 1673 5381 2974 1677 2947 8672 4229 2465 4366 8009 8067 6928 2382 8068 9964 0048 2435 4037 0141 6314 9658 9794 0924 3237 8969 0706 9779 4223 6250 8221 6889 5738 3798 6230 0159 3776 4716 5122 8935 7860 1588 1617 5578 2973 5233 4460 4281 5126 2720 3734 3146 5319 7777 4160 3199 0665 5418 7639 7929 3344 1952 1541 3418 9948 5444 7345 6738 3162 4993 4191 3181 4809 2777 7103 8638 7734 3177 2075 4565 4532 2077 7092 1201 9051 6609 6280 4909 2636 0197 5988 2816 1332 3166 6365 2861 9326 6863 3606 2735 6763 0354 4776 2803 5045 0777 2355 4710 5859 5487 0279 0814 3562 4014 5171 8062 4643 6267 9456 1275 3181 3407 8330 3362 5423 2783 9449 7538 2437 2058 3531 1477 1199 2606 3813 3467 7687 9695 9703 0983 3913 0771 0987 0408 5913 3746 4144 2822 7726 3465 9470 4745 8784 7787 2019 2771 5280 7317 6790 7707 1572 1344 4730 6057 0073 3492 4369 3113 8350 4931 6312 8404 2512 1925 6517 9806 9411 3528 0131 4701 3047 8164 3788 5185 2909 2854 5201 1658 3934 1965 6213 4914 3415 9562 5865 8655 7055 2690 4965 2098 5803 3850 7224 2648 2939 7285 8478 3163 0577 7756 0688 8764 4624 8246 8579 2603 9535 2773 4803 0480 2900 5876 0758 2510 4747 0916 4396 1362 6760 4492 5627 4204 2083 2085 6611 9062 5454 3372 1315 3595 8450 6877 2460 2901 6187 6679 5240 6163 4252 2577 1954 2916 2991 9306 4553 7799 1403 7340 4328 7526 2888 9639 9587 9475 7291 7464 2635 7455 2540 7909 1451 3571 1136 9410 9119 3932 5191 0760 2082 5202 6187 9853 1887 7058 4297 2591 6778 1314 9699 0090 1921 1697 1737 2784 7684 7268 6084 9003 3770 2424 2916 5130 0500 5168 3233 6435 0389 5170 2989 3922 3345 1722 0138 1280 6965 0117 8440 8745 1960 1212 2859 9371 6231 3017 1144 4846 4090 3890 6449 5444 0061 9869 0754 8516 0263 2750 5298 3491 8740 7866 8088 1833 8510 2283 3450 8504 8608 2503 9302 1332 1971 5518 4306 3545 5007 6682 8294 9304 1377 6552 7939 7517 5461 3953 9846 8339 3638 3047 4611 9966 5385 8153 8420 5685 3386 2186 7252 3340 2830 8711 2328 2789 2125 0771 2629 4632 2956 3989 8989 3582 1167 4562 7010 2183 5646 2201 3496 7151 8819 0973 0381 1980 0497 3407 2396 1036 8540 6643 1939 5097 9019 0699 6395 5245 3005 4505 8068 5501 9567 3022 9219 1393 3918 5680 3449 0398 2059 5510 0226 3535 3619 2041 9947 4553 8593 8102 3439 5544 9597 7837 7902 3742 1617 2711 1723 6434 3543 9478 2218 1852 8624 0851 4006 6604 4332 5888 5698 6705 4315 4706 9657 4745 8550 3323 2334 2107 3015 4594 0516 5537 9068 6627 3337 9958 5115 6257 8432 2988 2737 2319 8987 5714 1595 7811 1963 5833 0059 4087 3068 1216 0287 6496 2867 4460 4774 6491 5995 0549 7374 2562 6901 0490 3778 1986 8359 3814 6574 1268 0492 5648 7985 5614 5372 3478 6733 0390 4688 3834 3634 6553 7949 8641 9270 5638 7293 1748 7233 2083 7601 1230 2991 1367 9386 2708 9438 7993 6201 6295 1541 3371 4248 9283 0722 0126 9014 7546 6847 6535 7616 4773 7946 7520 0490 7571 5552 7819 6536 2132 3926 4061 6013 6358 1559 0742 2020 2031 8727 7605 2772 1900 5561 4842 5551 8792 5303 4351 3984 4253 2234 1576 2336 1064 2506 3904 9750 0865 6271 0953 5919 4658 9751 4131 0348 2276 9306 2474 3536 3256 9160 7815 4781 8115 2843 6679 5706 1108 6153 3150 4452 1274 7392 4544 9454 2368 2886 0613 4084 1486 3776 7009 6120 7151 2491 4043 0272 5386 0764 8236 3414 3346 2351 8975 7664 5216 4137 6796 9031 4950 1910 8575 9844 2391 9862 9164 2193 9949 0723 6234 6468 4411 7394 0326 5918 4044 3780 5133 3894 5257 4239 9508 2965 9122 8508 5558 2157 2503 1071 2570 1266 8302 4029 2952 5220 1187 2676 7562 2041 5420 5161 8416 3484 7565 1699 9811 6141 0100 2996 0783 8690 9291 6030 2884 0026 9104 1407 9288 6215 0784 2451 6709 0870 0069 9282 1206 6041 8371 8065 3556 7252 5325 6753 2861 2910 4248 7761 8258 2976 5157 9598 4703 5622 2629 3486 0034 1587 2298 0534 9896 5022 6291 7487 8820 2734 2092 2224 5339 8562 6476 6914 9055 6284 2503 9127 5771 0284 0279 9806 6365 8254 8892 6488 0254 5661 0172 9670 2664 0765 5904 2909 9456 8150 6526 5305 3718 2941 2703 3693 1378 5178 6090 4070 8667 1149 6558 3434 3476 9338 5781 7113 8645 5873 6781 2301 4587 6871 2660 3489 1390 9561 9728 .....ORIGINAL: George ElliottPye = 3.14159 = Ans 632.13cc [8|] For this level of performance it may just matter...[
))) PeteGeorge Elliott
New member
hmmmm...... eemmmmmmm....... ........that looks more or less correct ....[] good luck
] good luck
Tried using those figures and had to sharpen my pencil 28 times.........[8|]
you need an auto pencil sharpener Mike.. Although there's not much to show for it, this weekend was a full on working on the engine affair. First was the seized 10mm bolt as shown in the picture, this truly was a bitch. I tried all of the normal methods, grips, hammer and chisel, welded nut,heat and finally the horrid easy out but none would budge it, the steel had become welded to the alloy for good.
So I decided to drill a 10mm tapping size hole (8.5mm) but since the previous methods had left the bolt in a mess I needed a way of keeping the drill as true as possible. The picture shows the Alternator bracket ( not engine mount as I originally thought) bolted to the block, I them found a suitable sized piece of brass tubing that both the drill could fit through and also fir into the bracket hole. This was cut to length and had two functions, protect the bracket and act as a depth stop for the drill bit.
This worked reasonably well with the newly tapped hole close enough to the original position so that the bracket fits with all bolts tightened up. It was a pig of a job and it took a lot of time but at least I got there in the end.
Next was to remove all of the main bearing studs, this turned out to be a lot easier than I feared having struggled previously with the head studs, so much so that 3 of them I gave up on and let the engineering shop remove them before boring, mind you they struggled themselves and it cost me £160 + vat in labour.. ouch. studs were removed first using still-son's to crack the seal and then finished using the two nut system.
After all of the studs had been removed ( I left the small stud seen ( oil pick-up) as it was in good condition and not a stress item) it was time to re-tap all of the threads, this is very important and took a number of hours to do properly ensuring all of the old loctite had been removed before tapping, it's also important to ensure no metal or as little as possible is removed during this operation.
With the bottom finished it was time to re-tap the 10 12x1.5mm head studs, I was worried about this for two reasons. First they are deeply recessed which means very difficult to fix if something goes wrong and also the state of the threads from the 3 that had previously proved difficult to remove was very bad indeed. There are a number of tapped holes in the 944 block that for some reason ( i guess space) enter waterways, other tapped holes or both, one such is the front head stud above the water pump, this thread was particularly bad. Re-tapping the head studs took half a day , all of which was a nerve wrecking experience. The picture shows what I had to make up just to be able to reach the threads, still they are all done now so one more job out of the way, the picture also shows the nice job that Serdi's UK did on decking the block.
Now a question, I need to decide what finish for the block, I originally planned on polishing it but this tends to look very dirty quickly even with lacquer, so i was thinking of an engine metallic silver heat resistant paint that would look the same but last and be very easy to keep clean. What do you guys think???? Pete
Although there's not much to show for it, this weekend was a full on working on the engine affair. First was the seized 10mm bolt as shown in the picture, this truly was a bitch. I tried all of the normal methods, grips, hammer and chisel, welded nut,heat and finally the horrid easy out but none would budge it, the steel had become welded to the alloy for good.
944 turbo cabrio
New member
For sure the latter option - will make you just as happy but for way longer Very nice thread indeed although reading of all this thread tapping makes me really scared for my own build in the winter Thumbs up from Copenhagen! /Niels
Very nice thread indeed although reading of all this thread tapping makes me really scared for my own build in the winter Thumbs up from Copenhagen! /Niels
Hi Niels Thanks for the kind words, I think your right about the paint option, still not sure though as my instinct is a lovely polished alloy but that's only good for a show car, not one planned for everyday use. My son brought home some 500c silver paint tonight for me to try out so I think I'll give that a go and report back. BTW don't let me put you off your own build, I probably make it sound worse than it really is and if all else fails a good machine shop should solve it for you. I had planned on removing the alternator stud by machining it out on the mill but unfortunately the block will only fit upright on my mill bed and I hate adjusting the head to a horizontal position and then having to reset after, so by hand it was...ORIGINAL: 944 turbo cabrio For sure the latter option - will make you just as happy but for way longer
Kind regards Pete
Evening all Only one picture for today although it took a lot of work before taking it. I went over the block with a wire brush fitted in the drill and after blowing all of the crap off wiped the block down thoroughly with IPA. Next was the laborious job of masking everything up followed by a dusting coat of Hycote VHT aluminium paint , left for 15 mins and then two more full coats. VHT is a very high temp self etching paint that has very good adhering properties and is resistant to petrol and oil, let's hope so. As always when dealing with paint, cleanliness is next to godliness and even more so for this application, it's rated for over 500c so will be interesting to see how long it lasts.
Just need to get some loctite 574 or equivalent and I can re-install the crankshaft, so hopefully the next instalment will be just that, of course that's if I haven't forgotten anything which is more than possible... Pete
Pete
IIRC The workshop manual does cover how to ensure the alignment is correct using a VW gauge which I suspect is similar to a plastic gauge. Thanks for the heads up though, there's a lot to remember when assembling a Porsche engine. I've been in the city all day at a film screening so not had time for any work on the car. Hopefully I can pick up some suitable flange sealant soon and get the crank in. Pete
Ex Skyline
New member
I'm having Manthey rods on my 2.5ltr rebuild this coming winter. Dont know if they are in house manufactured or,wether they are indeed manufactured by Paulter and bought in. I am going to Manthey Motors in September whilst on my birthday trip to the "Ring" so i will talk to them and find out. I may also buy some other parts for Jon Mitchel to incorporate into the rebuild as long as i'm able to take another dividend this year (50/50).
Ex Skyline
New member
Forgot to ask, who is doing your machine work Pete?
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