Got my Crane 300 degree hydro friendly cams... if you want to rev the poo out of it... on a std bottom end??? Want revs 1900 is the answer. My 9A 16v Jetta did'nt want to rev either, but was flexible throughout its rev range.
1900's will of course want to rev more than a 2L but unless you are prepared to buy a steel crank and rods (2K in bits alone), you will never realise that benefit and get high power - a 2L will rev pretty well if built right (mine is redlined at 8.6K and slams the limiter)and will have loads more mid than a 1900. I reckon you would have to go to 10K+ for a 1900 to outpower a 2L and thats serious mod time - special waterpump, special alternator, flywheel/clutch assembly, synchro's probably wont work anymore so will need dogbox, std ignition wont work anymore....etc etc etc So IMO, 2L is better than 1900. Thats why the factory cars were 2L and not 1900 (admittedly 90mm crank 2L's but 2L non the less). There's no substitute for cubes as the old adige goes. If you are hellbent on trying some wilder cams on hydro, 276 is as far as it goes in Schrick range. Personally, I wouldn't use Bill's 300's - your bottom end ain't up to it. You can go to 283's on hydro from Cat cams, these have 11.5mm lift (which is probably very close to the latest spec schrick's that you have (but check) and almost 3mm at overlap - gonna get through the fuel ! Rob Rob
300 Cranes gave power from 5K rpm... If you're prepared to wait for them to come in.. worse than lag on a big turbo car. What bore/stroke combo was yours Rob? I cant remember. Chris>> if thinking straight up 276's you would at least have a pair of cams which can be timed together without the need for adjustable gear sprocket, if you did'nt want to fit one. maybe the sprocket is a "thing"
Unfortunately the internal Vernier is missing on my car so this is definately not the 'thing'. Remember Chris, mine and Graham's car peak power is roughly the same as yours at 6800 The only 'thing' that makes it revs further up is the crystal in the ECU.It is set at 7800. The car does rev cleanly but I put that down to miles...your block I suspect is still tight. Why don't you extend the limiter to 7800? As Rob said earlier your better off with 1.8T route for further power at less cost.........but there again you'll need to modd one of those which ain't cheap once you buy the unit plus the parts you will need ie larger turbo intercooler manifold etc etc. Ian
basically no matter how much power we all have we still want more ,, anyone know a cure for this addiction as im sure you`ll agree,,,, it`s very expensive!! Edited by: rradogolfman
Limiter is now @ 7600 Ian... Graham is just a bit stumped as to why it wont rev as hard as your or his cars. A certain amount can be put down to the fact that your engine is lightened/balanced etc & his has Battlestar Gallactica miles on it... Even so, although mine peaks in similar fashion, it then tails off very sharply. Moving the cam timing does nothing... He also thinks it idles too well (smooth @ 700rpm when cold) considering the cams in it, & in comparison to your own cars..Maybe some of this is down to DTA smoothing it out.. He has even suggested pulling the cams out & having the spec checked/measured...he isd that convinced that something isnt quite right..
My Jetta had limiter at 7700rpm, but peak power was some 1000rpm less, extended headroom for holding gears on track, but not cos there was high power there cos its was falling after 6800rpm on mine too.
I seriously doubt its cams, but t'bodies and mapping for the smooth idle. No k-jet flap to get upset about plenum pulsing and no plenum either. My 300's mapped in to a smooth 800rpm MOT friendly emissions too (took some time to achive it mind you) - The joys of fully mappable ecu's.
Cheers Bill, that explains it!! Im now thinking 276/276 in time & keep the car road friendly for going to shows etc....Will be good in terms of inter-cam set up too.. Looking at Robs plots from Stealth they would appear to move peak to 7Kish & I would keep the limiter at 7600 to allow gears to be held on track.. Just the ticket! Thanks for everyones input/advice
I had idle problems with those cams when it was on K-jet . Worse than Ian anyway. The smooth idle is just another advantage you have with the throttle body/dta set up.
Bill, How many revs can you go with the standard tappets before you get valve float? I was under the inpression that 7.5K is about the max with hydraulic tappets on a 16v and the wilder the cams the more the tappets are stressed so compounding the problem. Where does the power come in on a 300o cam? I would have at a guess at 4500 - 9000rpm. Cheers, Chris
Bill said his 300deg cams gave power from 5K upwards... IanB revs his car to 7800 on hyd. tappets with no issues, but I dont know of anyone who revs a hydraulic car further. 8000+ revs is steel bottom end/solid lifter head territory..
I ran my Ket 1800 KR to over 8k revs with my 296's and hydraulic tappets, mine came on cam later than 5k too Was a bit of an animal when it finally woke up, gave a few 2L 16v's a few scares at alconbury a few years back
Was it worth the wait when you fell off cam tho? my Jetta was 3 secs slower round combe with the 300's in it as I did'nt have a g'box to keep it on the boil and the flexibility is had on split duration cranes 260/270 was lost. Pistons also needed pocketing as the 300's had over 12mm lift! and >3mm lift at TDC!
Engine revs is only a part of what revs an engine can run to on hydrolic lifters It doesn't neccersarily mean you have to go to steel bottom end for 8k revs either, there is alot of work you can do (and is commonly done) to the rods and crank without changing to steel.
