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CHANGES

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Everything posted by CHANGES

  1. Yes , that is close enough .., I use 0.065'' which is a near as dam it 1.7mm .. unfortunately you have made slight error here ... The deck height is from the top of the piston crown , to the top edge on the liner. Because the piston can rock in the bore when checking, i always take a couple of measures.. 1 from the piston edge directly over the wrist pin.. 2 and 3 from 90' of wrist pin .. with 2 and 3 , I rock the piston taking two measurements on both and then the average will give me measurement when piston flat. This should be the same or close to #1 measurement if different i take the average of the two . But because you measured the piston in the bore at TDC , the volume you will have come up with will be the piston bowl and deck height together in one .. In this case you only need to add it on to the gasket and the combustion chamber volume along with the swept volume, to give total volume , then calculate from there .. hope that helps .
  2. What I was trying to bring attention to, is that the focus should be on ALL points, nothing should be overlooked as they are interlinked.. With the component changes made and the work that was done on the head , there was high possibility static C/R would increase significantly .. I am not sure how much Fabian was aware this tied into the boosted final C/R and the influences it could have .. You are quite correct in saying fuel delivery and ignition timing need close attention . However by maintaining the final boosted C/R, the fuel delivery and ignition should be able to remain within the factory settings .. It is far easier to gather this sort of data during the build , even if it takes time . By doing so it make you aware of any compensatory adjustments that will be needed , as in this case boost level.. I must be honest when i say, the SCR Fabian has is a lot lower than i expected with the work done.. Not sure how an 8.0:1 piston set up with a well skimmed head can end up a 7.76 :1 .. I did notice the piston bowl volume was measured in the bore , this is quite normal and easier to do with the forged piston crown shape. However this measurement will include the deck height volume as part of.. Fabian listed this separately in his data at 3.45 mm . This is 0.136'' which also seem a bit high , i normally expect forged piston deck height at between .0.010'' and 0.040'' depending on build spec. However there are several spec changes in this build , with machining and a cross over of parts ie early block late pistons etc which will mix up the norm .. If all the data is correct then this has all worked out for the good .. I would just ask Fabian to re check data content and reaffirm . As i say , the SCR is not an issue , these all vary when machined , its just the adjustment to the boost level that is needed to keep things within the ignition and fueling window..
  3. At 7.76:1 you would probably be fine.. You could also just tweak boost back a fraction to get spot on .. You can use one of the on line calculators to give boost for required final C/R. I have to take my hat off to how quick you did all the measurements.. well done .
  4. Unfortunately a compression check will not give you the exact compression ratio. You can divide back the psi reading you get by 14,696 as a guide , but unless you calculate in the cam timing / overlap , is will just be a figure. With the valves opening and closing earlier or later your compression check psi will go up or down . Because of the machining your valve timing will almost certainly be slightly off spec, so any factory psi on comp check will be off.. The early engines were the 7.5:1 but the piston crown you have now will be for the 8.0:1 .. This will also be influenced by the deck height you have, which can be influence by other factors. Your gasket thickness is part of the calculation , but should not be seen as a compensatory factor for piston change, etc.. The thicker gasket will only offset the head skim up to circa 0.010'' .. Valve recess / cut back will lower ratio but only to a point. When doing this you have to dial in the shim clearance setting.. Std they are 0.100'' to 0.085'' , you don't really want these going below 0.060'' if you can help it.. so you see the restriction.. The only accurate way to do this is to measure whilst you still have it in bits.. Otherwise its best guess.. uhmm. It is not really that important what the actual C/R is , as long as its not silly high.. But knowing it is ... What you want to achieve is the correct final C/R under boost. This will then allow your ignition , carburetor and fuel type tuning to be in sync as designed .. Your adjustment factor will be your boost settings,.. you may have some anomalies off boost but they will be very slight and insignificant in comparison. But without knowing the exact static C/R you wont know what final boosted C/R you will be running at.. Sorry if this was a bit long winded , but i would rather you be aware of fact than carry on regardless.. Keep up the good work ..
  5. Looks very nice Fabian , , what extra's have you had done , other than change the valve material spec. ( so much can be done , it would be nice if you could list it all with photo's ) ... I would also be interested on the chosen combustion chamber volume , looks like its had a good skim and valve seats cut back.. You will need to know this , along with your piston bowl volume , deck height and chosen head gasket squish size , to calculate you static compression ratio. Especially as you have changed piston type and block as well . When you have your static C/R figures , you can then calculate your waste gate boost setting requirements to give the desired final C/R. Otherwise you could be showing stock boost level but running much higher final C/R.. I would also put a bit of thread sealer on those grub screws. Keep up the good work.. D
  6. This is totally correct , and as we discussed, it does make a difference, maybe very small , but all the little things do add up .. They are not.. basically they fully shut . However they never produce a full cut of .. The stop screw should be set to just touch when they are fully closed , This will prevent the return springs making the BAV have a forced contact with the TB its self.. In the past i have seen TB's with marks from the BAV in the TB inner wall , at the contact points.. You will always find one balance screw on each TB fully shut , the other cracked to balance the inconsistency in assembly.. Once you have disassembled them this original setting go out the window.. Also you will find over time even with the filtered air that passes through the bleed hole past the adjustment screw , it still gets a deposit which will change the flow characteristics.. This is normal and found in just about every TB set up I check.. This is true when the cars were new and being serviced by the dealers... Rest assured any post tuning that will have been done would of included checking the individual balance criteria.. The anti tamper screws will have been removed and replaced if adjustment was needed.. Now these cars have so many years and miles on , it would be prudent to check , This is done with a throttle flow meter , which is a very simple process to do .. Once you have balanced and set the whole system you should have tick over controlled by the ECU via the IAC valve . If this tick over is to low , I would first check the IAC function , if all is ok then any micro adjustment can be made via the stop screw or the by pass balance screws .. It is very rare to need any micro adjustment if everything is working as it should. However , most of these cars are circa 30 years old and still feature original injectors , which have never been cleaned or replaced, along with other ignition parts like the coil packs .. All of these over time deteriorate , so having a micro adjustment facility can be useful.. to compensate. I must stress that you need to be aware of what you are doing and if unsure consult a reputable dyno technician to do final set up, then do a power test to clarify all functions are performing correctly.. A power run is the only way to insure your ECU is calibrating the engines functions correctly ie. secondary injectors coming in on time , The TPS function is calibrated within range ETC ETC,, So if unsure just Ask someone . !!! A useful bit of kit to have
  7. Just to clarify a point. The polished s/s part is a reflector. The asbestos bit is the heat shield.. There should be an air gap between them to also help dissipate heat.. Failure to fit the bit you chucked will result in the s/s reflector being able to come into contact with your leads.. This part WILL get very hot from the turbo, and WILL damage your leads over time. Lotus would not have gone to the cost and trouble of having it made and fitted if it was not essential ... If you choose not to use the actual part , then i strongly suggest using an alternative.. It will save ignition issues at later stages
  8. A good way of saving this sort of area is by metal plasma spraying. This can build up the surface without introducing the heat levels that cause distortion.. It is quite common to see this used on classic cranks that have reached their machining limits. Once a suitable thickness has been achieved the area can by ground to size.. If in the case of thrust bearings the area is still on the low side ( needing thicker than available thrust bearing ) , then get someone to machine from a bronze cord the required thickness, job done .. This process is nothing new , vintage and veteran car restorers along with historic race engine builders do it quite often when no replacements are available ..
  9. Simply use one of these , with spec from bolt.. Or ask ARP for torque equivalent .
  10. This is so true and also very important.. If only a few basic adaption parts are available , then the concept is incomplete and untested.. With anything development wise there is always issues, these only get ironed out when someone seriously tests them .. If kennady have not done full make up testing with data to back up , then all you are buying is a box of bit that you have got to try and make work.. This is a very interesting option with great potential along with info from people who have fitted and tested .. What would be interesting would be the details on clamp and release loading's, along with torque capabilities.. The std V8 plate from AP racing had a corrugation section within the friction plate to make it more compliant than a race clutch , but as was said can still be a bit sharp compared to other clutches.. When asking AP for the 550 ft lb version , i was presented with a version that did not have the corrugation section due to space constraints, which made it less compliant so more of a race clutch.. To offset this we introduced a staggered plate engagement to make it more compliant. This does work well but will wear one plate quicker than the other. So I for one would be very interested in an alternative that bolts straight in , as long as it can take the higher torque levels. As for the lightened fly wheel , I agree a lot can be facilitated from doing this . Personally i would not go for the letter box option, I have seen far to many of them fail over the years , straight drilling's can achieve similar results with better reliability.. Pic of custom light weight drilled chrome molly version for the 4 pot engine using the V8 clutch .
  11. I have recently had this discussion on another Forum with someone who was adamant that it could be fitted with nothing more than re drilling the original flywheel .. When i pointed out all the other aspects and technical details to doing such a conversion he got very insistent and insulting... Funny how some don't want constructive advise and have all the answers.. At least on here we have people looking at the wider picture and exploring what is needed.. As someone who has traveled the road of transmition woe's due to performance upgrades , i have looked at most options to fit my needs.. Most of the time an alternative was binned due to drive shaft alignment, if this is not right then you generate all sorts of issues, and moving engines backward or forward is just not practical.. Primary shaft length is always an issue when fitting an adaption plate, shoving and extension on it is a cobble and will fail , so a custom flywheel with spigot bearing fitted within to match up the two halves is the common solution. Next is clutch.. If you have upgraded your power enough to break the tranny , then your clutch will not be man enough for the job and will need sourcing at the same time. This will all need to fit on the Porsche primary shaft and within the Porsche bell housing as it is not detachable from the box like the UN1 is. You will also need to adapt the clutch release mechanism to match the chosen clutch with the gear box and the Esprit clutch pedal ratio.. These are just a few points you need to be aware of even before you start manufacturing rear mounts , gear levers , selector mechanisms and sourcing suitable cables, not to mention adapting drive shaft fitment. All of the above would be very interesting project to do and a great challenge.. BUT, will it fix the initial problem ' power/torque limits' .... In most cases NO .. Some are a bit higher and better than the standard UN1 027 but not by much and the gear ratios / final drive don't all suit the Esprit set up.. The 987 6 speed box out of the 3.2 pre TDK is the best of the Boxster options , however this offers less than some of Audi 01E box's.. What you also need to know is there are several variants of all of these , which all look the same from the outside.. internally very different.. When buying second hand you really need to be sure of what you are buying , because they wont have it back when you have fiddled with it.. Another point to consider is , any second hand box you buy, should be rebuilt to insure it is not faulty, so cost that in . If you buy a new or specialist recon box , they ain't cheap.. The second hand box's on the net for under £1k are usually tired or broken , so you are taking a chance and will need to factor in the rebuild cost and parts. Which brings us back to the UN1... When you drive your Esprit sensibly , you should have no issues. If you drive it hard but have considerations for its weaker points , you will minimise any issues.. But if you are regularly developing over 400 ft lb spike torque loads and want to use it , then do a UN1 upgrade .. There are more options becoming available with on going developments and testing being done . There are GTO , Elite Racing and Holloway already available , all well proven with ratio options etc.. These kits only cost the same as buying a decent standard 987 box but without fitment issues .. There are even higher spec's you can go to using the UN1 as featured in the 412 thread in Esprit chat section . These do come at a price, but when fully costed out will probably end up cheaper than a donor conversion with comparable torque capability, but without the fitment hassle... There are stronger ring and pinion options available . You can strengthen and treat your original as the cheapest option, or have a special high torque set made as I have .. Used along side one of the aforementioned gear kits , you should be able to hopefully meet all your torque requirements.. To summarise , A 3.2 ltr 987 Boxster develops 236 ft lbs of torque through its gear box, the 3.5 ltr V8 Esprit develops upward of 300 ft lbs through its gear box.. If you are having power issues with the Esprit box, Why are you looking at the Boxster box. I believe a lot more research and proper testing will need to be done with the 987 box before it can be considered as a stronger alternative .. This is Just my personal input on the subject based on my own experiences and data available .. Hope it helps shed some light on what is available and involved..
  12. Fitting the liners , People have different ways of fitting liners, but this is the method I have used for years without issue . Once all the liners have the nip heights set / adjusted to required spec and are in correct orientation dry, mark them up so they can be removed and placed back in exactly the same position when sealant applied.. I do this by simply applying masking tape up the center line of the decks.. see Pics's Next jobs is to remove all liners and prep all parts ready for next stage, this is done so you are not looking for any part in the middle of a procedure ... Wipe all mating surfaces on liners and block with a spirit wipe to remove any oils etc. Prior to fitting liners it is time to refit all the block/head studs and locating dowels .. important to note these are torqued in with oiled threads , i also apply a small amount of blue thread lock. When all fitted prep area where liner # 1 is installed by first wiping with tack cloth , then smear the surface with your chosen sealant. Then prep the # 1 liner with tack cloth and apply sealant to the contact area. Carefully slide the liner into place . When fully down give slight twisting action side to side to ensure fully bedded . You will find this will be quite stiff to do compared to when dry.. Whilst doing this ,using a long straight edge align the datum marks on the decks to ensure fully straight in position .. Failure to do this now may cause alignment issues with the flats on the liners not being square to each other or even touching on the points. By the time you have prepped and fitted liner # 2 it will be awkward to re orientate # 1 , as the sealant will have already grabbed .. Repeat the same procedure on all 4 liners . You should get a nice bead of sealant at the base and all around the liner if fitted correct. Next job is to remove the masking tape markers and fit an old compressed but very clean head gasket, followed by the cylinder head. Torque the head down to 40 ft lbs in the recognised sequence, ( remembering to oil the threads) . This will compress the liners into their final position. Leave like this for circa 12 to 24 hours .. Before leave to fully cure, invert the engine . You will see another bead of sealant on the base of the liner. Remove this with a cloth and spirit wipe . Because the sealants used here are mostly anaerobic they will not fully cure in that environment. To prevent the sealant polluting the oil it is removed from that area, it is not an issue in the water jacket where it will dissolve and disperse . This conclude the fitting of the liners. Next job will be to match the pistons to the bores and gap the rings ..
  13. No . The free length of the shock absorbed / damper inside the spring will restrict the travel length of the spring.. The damper basically locks the spring in place on the seats of the top chassis mount and lower arm ...
  14. A lot depend on the liners deformity / dent and how much the alloy will need machining to remove it. The typical thickness is of Nikasil between 100/200 microns , You need to measure what was there before , see how much thicker you can actually make the plating, then allow for the honing . If the dent is less than this then you are in the pound seats so to speak .. however you usually find they are out of spec.. If you are desperate to stay will Nikasil liners , you can always go out by 0.020'' have them all re-plated / honed to that, and purchase oversize pistons..
  15. Been there done that , but with a washer.. wired and fired 031 (2).MPG
  16. As they are so far out , I would go for set wrong on last build . Experience will show it is rare for a valve or valve seat to ware significantly without there being an underlying issue .. The most common ware point is the valve stem into the shim . This can be seen on the shim and can cause valve clearances to increase by 3 to 4 thou , although in most cases just 1 or 2 thou.
  17. The one you said you looked for but could not find , Knowing all along Shan would find it for you.
  18. That magnet is much as i would expect on any box strip, just a bit extra on this one due to failure. You always seem get a fine deposit on them , nothing to be concerned about.. Any chunky bits or fine slithers is a different matter . The stuff on the magnet when you wipe it off has a feel more like a graphite than iron filings.. when you rub it between your thumb and finger it should not feel lumpy. ( which mine did in this case , but expected).... Hope that helps put your mind at rest.. ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ The above is the post mentioned , What I believe Fabian had was flakes which are more serious and quiet rightly worth investigation.. As I stated above the if deposits on the magnets feel like a grease , no issue , but if any granular or flaky slithers should be looked at..
  19. It is always worth remembering that the suspension bushes should be torqued up at the correct ride height.. The fact that they hold an elastic tension and not freely rotational will influence suspension rest position.... So when you have set the chassis at the correct ride height , slacken off fully and then re torque the bushing pinch /pivot bolts to ensure the elastic tension of all the bushes is in the correct neutral position at designated ride height ...
  20. Hi Chris , If you just type in ' REM treatment on gears ' on google you will get a list of companies who do it.. you can then find someone local.. However one should remember REM is just one part in processes available . It does have benefits when just done on its own, but to get the most out of what you have , you should also consider having the gears put though 'cryogenic heat treatment' . This will remove the residual stresses normally found within the gears . You can then, and is normal in these sort of cases to be followed up by 'micro peen blasting ' to remove unwanted surface tension.. The next step after that would be to have all the gear 'lapped in', before finishing off with REM treatment.... Quite a collection of processes which are not easy to find all done under one roof.. So my suggestion would be to read up on all the processes individually , then decide how far you want to go and find a specialist who can get it all done for you.. They should be to advise you accordingly on what would probably be best for you .. hope that helps. PS .. you need to make sure the gears you have do not have micro cracking already within them before committing to process .. If you find such cracks just replace those gears before proceeding.. A decent company will do that for you ..
  21. It will depend at lot on how much you do yourself.. If you just sent it in to get fully done and returned finish , i would expect you would spend around £2-- £2.5 k mark for full treatment... My costs also included designing and making the new gears from billet so very different.. I also sent the box in stripped ... It will certainly increase your torque loading capabilities... On a foot note i asked for the selector sliders to be super finished at the same time , i did this to try and smooth out / refine the gear selection at the same time ..
  22. I thought that expression was glee not Pee.!!! As you say ,It can pull a few wrinkles out of the face on us oldies, but you are to young so must have just been a smile.. Although you are one donut up on Sparky.. I seem to remember that gave us the giggles ... But to answer your question , it made another experienced Esprit owner quite flushed , and bought on an asthma attack on another chap, to which he he said after.. I did not bloody expect that.. So quite quick...
  23. Patients , young Padawan , one must feel the force , not controlled by it..
  24. You know you will be the first to test the limits. 'After me '... As the only person to have done any pre test driving on this , you are the only one that can give validated comparison feel data... I can not wait to try the new ratio set up , 😀
  25. There we have it , from the horse's mouth 😱 , A customer saying the trader should come first.. . But we know the customer will always come first, it the way of the world.. Sorry Richard yours is first , I will have to wait ..
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