SKiddell

IMHO You could do alot worse than look to the Japanese tuning scene for ideas, anyone that runs big rev 340+ HP NA engines (credible dyno figures not some back yard shade tree setup)running 11 second 1/4 miles has got it right. On many of the engine pictures I have seen ATI seems to be very popular. I have used one for many years, not cheap but spares are readily available.

I can thoroughly vouch for the copper gasket route. I use a 1.4mm copper gasket machined to fit 88mm bores on a P90 head and N42 block with 12:1 comp. When I first used it I had to ease it very slightly with an air die to fit, heads been on and off so many times I have lost count, just clean the gasket up with wire wool (anneal if necessary) spray with Hylomar gasket dressing and re fit.

I have got a well skimmed E88 to run at around 11:5 to 1 static but thats on UK fuel (99 RON) I accidentally ran it on 95 RON and it took 2 pistons out in a heart beat, cut through the ring lands like a blow torch. That E88 Head was skimmed down to 106mm thickness, chambers were down to around 35cc's with an 86mm bore and a 1mm felpro gasket(can't remember exactly it was a while ago) A lot depends on what the dynamic compression ends up (static compression combined with the cam profile etc) I have seen a "theoretical" high static compression motor that has run well on pump fuel due to the cam profile EG Schneider stage IV (which has bugger all lift on overlap), conversly I ran a 320 duration cam that had over 5mm of overlap lift which was a pig. Just my £0.0123693488 worth

Not all stainless grades are non magnetic the term stainless is more a generic term used for steels that have very good corrosion resistance (usually have high chromium and nickel content) To be completely non magnetic a material requires a magnetic permeability (MP) of 1, some of the high austenitic steel grades reduce this magnetic response to a value where it is not easily detected and thus appear to be non magnetic, however this 100% austenitic steel is often not practical as some ferrous component no matter how small is often present, typical MP numbers for austenitic stainless steels are in the region of >1.05, super high grade austenitic stainless steels used in research environments, MRI scanners etc. get as low as 1.005. Martensitic stainless steels have noticeable magnetic properties but are still classified as "stainless" as they also have high corrosion resistance.

Agreed Tony however like a lot of things there is little (useful) written about it so one has to discover it all over again.

Echoing what Leon says, the overall runner design will greatly affect the characteristics of the engine and as such its difficult to work at a this level without knowing the intended purpose (Road, Race, Rally) or induction method (Carb, TB, Forced) and the exact specification of the intended engine. Just as background info From a recent rolling road session we experimented with different ram pipe lengths on an individual TB NA L6 for a whole day, the results were astonishing, long pipes gave great low to medium range cylinder fill and thus great torque (252 ft/lbs at one point which is a BMEP of over 200 and a VE of 111%) but the car ran out of steam around 6700, shortening the pipes brought the low to mid torque down a little (we settled at 242 ft/lbs ) but lifted the peak power up to 7300. The worse results were for open ram pipes and no pulse plate this absolutely killed the power curve (theory was…out of phase reflected pulses from the inner body work), we gave up on pinning it down as the results were so poor. Of course these results were a net result of changing the overall tract dimensions resulting in velocity changes, possibly enhanced venturi effects and pulse wave tuning.....this experiment no doubt would have delivered different numbers but probably the same overall "effect" on Carbs and gives a little insight into just how critical the dimensions can be, ….I guess what I am saying is that you need some idea as to the required dimensions and then they will influence the design On a side note would really like to try short body TB's in an attempt to get the overall tract length below 300mm. Now you watch TD or JC come shoot me down

Same here really I have not been able to find rhyme or reason behind the alpha numeric codes and have noticed significant differences not just at the main bearer pad but on the under side webbing (to the point of fouling on the spring retainer in the worse cases) and the offset at the lash pad end skewing the wipe pattern (on the cam lobe not the rocker pad) left or right by up to several mm. I have matched up a number of "codes" but they still seem to have these differences therefore the codes must mean someting else (batch, date, time ??) Alan (T) if your around, or any one else do you have any insight as to this coding, any info would be greatly appreciated.

When we built my steel motor last year we took the opportunity to measure the wall thickness in several areas across all bores (ultra sonic unit), my plan was to only go to 88mm on a stroked billet crank, and boring out to this left between 150 and 160 thou of wall thickness. Personally this is a minimum for me as I am running around 12:1 compression and didn’t want any barrelling of the bores. Recently it’s made close to 290 FWHP on the rolling road with 242 ft/lbs of torque (not bad from a 3 litre that has to be driven on the road to comply with club rules), with that I don’t see the value of scraping out the bores further for what would amount to small power gains and potential reliability issues (personal choice) Re sleeving (Tony D) another block we did ran into porosity issues at 88mm and we had to sleeve one cylinder (fast road engine), the company we used did a cracking job and its hard to see why its not done more often (cost sure). If I had the budget and needed to go to a big bore then I would sleeve the whole damn thing given half the chance, and leave nothing to chance, nothing to stop you using some of the more exotic materials on the liners and rings then.

Z-Ya Out of curiosity, how deep are your retainers and what thickness pads are you running I have seen a pad "skew" in a shallow retainer.

Couldnt possibly say either way:mrgreen: On the back plate we included a reversed lip that the clip "hooks" into. The clips are secured into the main box by securing plates and nylok nuts....I then use aluminium foil race tape over the top, once bitten and all that.

I run 65 mm carbon fibre stacks under the airbox, clearance is fine. The carbon fibre air box does a good job at keeping incoming air temps down (around a max of +15 degrees whilst driving but more often lower) due to being connected to a cold air feed that goes through the rad support panel to a drum type ITG foam filter. The CF backplate is cut out (6 x 50mm or 2" holesaw) to sit between the stacks and the carb bodys (ITB's in my setup) the stacks then hold the backplate in position, stainless overcentre clips then hold the airbox onto the backplate. Its been on the car for 2 years with no issues, doing around 150 drag passes, several really hard track days and umpteen thousands of miles on the road.There are a number of cars in the UK using the same solution in either glass or CF. I'll try and post some "install" pictures I sell these units at cost (materials+labour) although the high dollar to £ at the moment would propably make the whole thing impractical. Good for me buying stuff at the moment though:mrgreen: We started making these after a very VERY bad incident with a $300 aftermarket, black, non flowcoated, fibreglass unit spat a rivet into number six inlet and nearly trashed my engine:fmad: the rivet pulled trough the thin glass and trapped itself under the inlet valve, the valve stuck open (partially) and the lash pad popped off its seat, the rocker broke, the seat was mashed and the valve bent. They shouldnt have used rivets unless supported correctly and riveted the right way round The makers didnt want to know about a replacement so we set about a redesign. I won't mention who they are as thats bad form. PM me for any other details

You could get one of these I supply them (I own the molds and a collegue/friend makes them) to guys in the UK. Full carbon fibre (or glass if required) colours possible. comes with 6 x stainless over centre clips and lip seal Can be connected direct to 80mm cold air feed or cone filter.

Get out of it, turbo's are for people who think turning a dial is tuning:biggrin: (good job I'm 4000 miles away Ha).

just Newtonian Physics, (He was the English Guy with the apple yeah) I agree its not spot on ...never said it was..but hey claiming to do a 13.9 with no timing slip is hardly accurate is it bud The above formula will give you a reasonably close figure on what your setup can achieve...not what it will achieve Err Duhhh!!! A coefficient by definition is a constant not a variable. looks like you made about as much contribution to this thread as in building your engine (s) Anyway lets respect the thread owner and other interested parties and keep it on topic, I for one apologise for taking it off

Not if you don’t have a timing slip you didn’t, so far you only have a slip for a 14 second run so 14's is all you got, you can beer-talk all you want but until you can repeat it you’ve got squat. I once got a 12.7 @ 111 MPH (with a ticket) but I don’t claim it as it was a "footed" run, IE the track marshal couldn’t be bothered to stage me properly and fudged the light with his foot. I can however reliably run low 13’s (18 runs this year sub 13.5, 40 runs this year under 13.8) so I can safely claim, low 13’s nothing more. I also don’t get why people think we should all be running 300HP, to get anywhere near 100HP per litre is very tricky and costly…the pro builders on here (Braap, 1 Fast Z etc) will tell you….why no one is listening to them God only knows. And regarding I’ll treat this statement with the contempt it deserves, it clearly shows your total lack of understanding on this matter, professional and amateur drag racers have been using calculus for years. Clearly you are neither, so how can you speak with such implied expertise See http://www.crew-chief.com/ http://www.web-cars.com/math/quarterjr.html http://www.altalabinstrument.com/software.html The NHRA even do correction charts for altitude Summit Racing even have a log book available so you can log the weather conditions to use later in your calculations A good friend and mentor of mine who used to run in “Pro ET” a UK race series (regularly ran 9’s so he knows what he is talking about) first put me on to this and I use Quartermaster to plan out my entire race season mods.