Mine runs slightly cooler than that. If I do 70 for a while it gets North of 100 maybe to 110 but the thing that slows me down now is the CHT as you would be amazed how much faster you can get to high temperatures on that if you are thrashing it, and how quick it drops again. I gather 425 F is the max you want for CHT but I try to stay below 410. I can cruise all day at 65-70 mph and CHT will be 350 to 400 F and oil will be 80 to 100 C. I bought Stack professional gauges for oil pressure and temperature and have a genuine 914 taco plate for the temp and a Paul Weeding adapter for pressure. The best CHT gauge you can get is the Dakota Digital one. VDO CHT are cr@p according to Ratwell and they have an extensive explanation of why the VDO one is hugely inaccurate depending on ambient temp (it isn't auto corrected for ambient so cold to hot day swings the readings a lot). I have no reason to avoid VDO oil pressure and temp its just Paul W mention he rated Stack in a post ages ago so I went that way (I got them from Demon Tweeks by the way but ordered the CHT one direct from the USA with a made to measure VW bus length temp sensor as you can't cut and splice the CHT wires)
Quickly nipping back to carb questions..I don't mind the posts on CHT and Oil pressure instruments etc, it keeps them in my memory So, the Solex Carbs I have are brand new 32/34 PDSIT ones (or summat similar) so Im assuming they are 34mm choke sizes? The 1641 Im currently running has 34 ICT's jetted to suit. What Im thinking is of removing the 34 ICT's and fitting them to the type 4 (when transplant time is due). Will ICT's work with a 1911 type 4 motor, jetted to suit?
I doubt it. eg ICT's have 28 chokes. I've just choked mine down to 28 this evening and set the mixtures but not test driven. If ticks over more smoothly and the exhaust note is more thuddy. Sounds proper meaty. No doubt will drive like a strangled pig.
I really don't mind! The info you guys are posting is reminding me of things I want to add when we swap motors! Carry on posting
Bugger So Ill be underfuelling with 28mm chokes for a guess and cause issues down the line. I guess we can start with the Solex carbs then and see how the land lies!
They will be 26mm chokes. Just check em with the vernier. They could be smaller, possibly 24s but 28chokes are available for them or just take the chokes out and machine them out. As they are designed to take the larger chokes but as for jetting...?
I wouldn't believe everything you read. Mine would barely run and undriveable with 32mm chokes. 30mm transformed it and probably right for the engine spec, but I have cam with almost 1/2" lift and 283 degs duration. I think you'd be pleasantly surprised how well a std 2L T4 drives with correctly jetted ICT's so don't chuck 'em.
In reality, if I didn't hope mine would be good with 28mm chokes I wouldn't be trying them. Mine will rev off the counter (about 7000 rpm) without any hint of a petrol shortage in 2nd and 3rd (4th's a bit fast I think) with 30 chokes - harldy strangled? I'm hoping it'll be a bit more grunty at low revs and if the power fades a few thousand RPM sooner it really wouldn't hurt.
The ICT's are being used at the moment on the 1641 - somewhere I have a list of the jets we used; we should be able to find out easy enough! cheers for the reply matey
The cam we went for in the end was a stock profile (I wasn't brave enough to go for a hot ish one; that's for the future) so, I guess we could be on to a winner as its a 1911 motor they will be going on to. It isn't built for high speed running either so we have nothing really to lose by popping the ICT's on (aside of manifolds and linkage) I feel a plan is forming! We have a good tuner close by, Peter Burgess so all could well be good!! Cheers Steve
Not to worry Dicky, I have the ICT's and the Solex' to play with..if one doesn't work, the other will! I can, however, easily measure the Solex's and see what is what
test driven with the 28 vents and the results are... A bit more grunt at the bottom end BUT outweighed by being strangled over 4000 rpm defeating the object of the long duration cam. I think the only way I can grunt it up is fit a milder cam. What I'll probably do is exactly the opposite, turn it into a screaming nutty engine for fun and build a proper large capacity day-to-day camper engine as well. All good fun though. OHC - how I dream. When I was a nipper I changed one on my Mk2 cavalier. I had not a clue what I was doing, no book etc and it took an hour. The cam is in the wrong place.
Sounds like great fun mate!! I have decided to go with my existing 34 ICT's and transfer them over, I have a set of manifolds and linkeages on the way whats the worse that will happen, I get good results Is there any VW books which tell you all about the cams and how to fine tune with carbs etc. @Owen Snell linked one up for me a while back, I cant find the link..it will make good holiday reading in the summer.
This one? http://www.amazon.co.uk/Four-stroke...0&sr=8-1&keywords=4 stroke performance tuning Good general reading, not specific to VW.
