After a few weeks of not being able to do anything on my track Sprint I have now finished refurbing the head, the head is back on & valve timing completed.
Inlet valves fitted.
Fitting the exhaust valves.
The spring on the left (green) are the uprated ones that I have taken off to be replaced with a new set of standard (red), after taking advice from Bodgerben it would seem that the uprated springs aren't necessary unless you have the STR0139 cam, & can even lose you bhp.
All valves fitted.
As this is a new cam, valve clearances are unknown so I just put in a set of shims all within a few thou of each other.
New cam shaft laid in place.
After 3 attemps, all valve clearances sorted & head ready to be replaced on block.
And here's one on Mary polishing some unknown car bits.
Sprintless for the first time in 35+ years. ... Still Sprintless.
Engines, Gearboxes, Overdrives etc. rebuilt. PM me.
Mart, the springs on the head I've just stripped are all 'green'. The head was fitted with a 16VT14 camshaft. Are standard springs the thing with this cam then ?
Only fit uprated valve springs when you plan on revving past 6500. Note the plan bit - the ocassional 6800ish with new springs has not harmed any of my engines. If 6500 is your engines limit (you've done no bottom end work to help the crank go past 7000) stick to new standard valve springs.
Engine power will be used opening those uprated springs, and if you're not going to rev past 6500, why waste that power.
Mart, Ben, it seems that the power band for this cam is 2750 to 7000rpm. I've had the bottom end balanced but I really don't think I need 7000rpm, maybe a little over 6500 now and again as Ben suggests. Although I want to have a few giggles, I really need my car to be suitable for daily use too. Won't this cam be a bit too much ? Looking at the specs for some of the other cams, I reckoned something that comes on at about 2000rpm and runs to 6000ish would be better ? All advice welcome
Ken, thanks for your pm. I'll give you a call when I've decided for definite what I'm doing.
I've used a number of different cams in Sprint engines over the years, these are my findings and what I have and will continue to use.
Always use a vernier cam sprocket, even with a standard cam to get the cam timing spot on.
I will not use a reprofiled cam, the combination of reduced follower bearing surface (to head), reduced opening ramp (the cam almost hits the follower and tries to push it sideways), large shims and sometimes worn cam bearings (the cam itself) have put me off. I had a lot of follower wear when using reprofiled cams, and as we are now spoilt for choice with new cams would not go back to a reprofile. After 5 thousand miles of using a reprofiled cam have a look at the wear on the side of the follower. I used to do that mileage in under 4 months.
For a daily driver I use a new standard cam - not a second hand unknown condition cam. Very good low down torque, happy to potter around and still able to go round to the rev limit with no holes in the power.
Track day car I use a STR91, docile enough for driving to-from the track, and powerful enough to have some fun, but can be a pain when the car is fully loaded, or pulling away from steep junctions.
I've not used a STR91 with HS6's, only HS8's and Dellorto 45's - HS6's may work better for a road car, but I like the standard cam and HS6's so I'll stick to them for my road engine.
Back when I was young and keen I would swap cams around depending upon the time of year, weather and if I was doing a sprint. I had the cams, followers and shims all put to one side ready for a swap. Whenever I went back to the standard cam I was amazed at how much nicer for everyday driving it was. I used this car for work and fun.
This car had twin 45's and I did not adjust the chokes, jets etc. per cam. It was rolling road jetted when using a TT10105, and I stayed with those chokes and jets.
I now think where the engine will spend the majority of its life, and for a road engine use the standard cam, and a track day engine use the 91.
A bit off topic, but I would use HS8's on a road car (standard cam) but not 45's - although they look and sound great, sitting in a layby on cold foggy mornings waiting for the carbs to de-ice has put me off using 45's on an everyday Sprint.
Looking great Mart!
Well Ben has finally made me just order my vernier from Kent Cams.
So at the moment I've got the spare head being stripped to take out mild road cam to replace with the reprofiled (oh ho) (we think tt10106 .408)cam. My ole man is trying to talk me into stripping the spare engine I've got and to get it rebored with new pistons bearings etc. Where does it all end...this could be heading to the divorce courts. I dont have a Mary quite contrary! , Mines more likely to
Oh and forgot to add....I've got dellortos but they're 40's, so i'm afraid that's what going on for the time being. Will i have to blank off the old fuel pump and install a facet and regulator, and if so, can anyone recommend where and what i should be looking for??
I am also in the middle of rebuliding the cylinder head on my Sprint. I ve been reading a couple of articles on the Sprint engine, one tells you to leave the valve stem seals off when rebuliding for greater lubrication. To me this doesn t make sense??? Whats everyone else do.......replace or remove???????
Thanks Ben, got the vernier, got the HS8's, just thought it would be worth have at least a mildly uprated camshaft to make better use of them. I am not going to re-use the 'green' springs as I picked up a set of new standard springs on the bay a while ago for a song ! I agree with you about re-profiled camshafts. I have a new standard cam that I got for a tenner years ago. I may well use that initially and go for a new mildly uprated one later. Thanks for the advice, I should be in a position to start re-assembling my engine week after next. I'll be able to crack on knowing exactly what I'm going to do. I can't bloody wait !
Ian Mack : I have never used valve stem seals. The Sprint engine doesn't need them. If it's burning oil on over-run the guides and/or valves are worn.
... Still Sprintless.
, Mines more likely to 
