19 replies to this topic

[Inno]

.....a short update....after some research I decided to go with:

• AC Dodds RS camshaft
• Minspares AEG 584 followers,
• twin springs AEA 525 160lbs
• and C-AJJ4037 bronze guides

 

....still didn't decide which valves to use...and many other things....

 

...researching about Megajolt - problem is I do not have RR with any Mini experience within 1000 miles radius so I am on my own regarding carburetor and ignition one way or the other....only road testing so I am trying to grasp as much as I can because I will need it...

 

..back to Megajolt....if I take to the consideration wear on standard Dizzy and also need to tune it without RR with loosen springs or weights It may be that Megajolt with at least yellow Aldon map can be a good starting position without all issues with dizzy and moving parts. Price is similar as Yellow Aldon or similar dizzy and even cheaper than "123" and I can take my time to drive it and play with the map on my comp and move it back and forth to gain better performance (same as I would need to do with any dizzy..... ......whatever I do I need to do it without RR

 

....also crossed my mind to buy lambda and few more sensors and connect them inside the car to monitor parameters....it sounds crazy but it is few hundreds pounds investment and I can get clear picture regarding mixture and other elements and act accordingly....with RR £50-60 per hour and fact I do not have it anywhere near, £250-300 is not that bad to come closer to better tune....just thinking loud....

[Inno]

You could use those valves which already have the back cut done, or if you have access to a lathe you could save yourself a decent amount of money and use the road spec valves and simply add a back cut to these. Unless you're planning on hitting 6,500rpm + on a regular basis the road spec valves will be fine.

Phil.

Thanks....I have standard valves now and not perfect ones, plane to buy 35.6...that is why I asked.

 

Not sure I will ever go to 6500...probably from time to time but rarely .....full focus is on torque at lower rpm...if bigger valves can help a bit I think I will go for it.

Minispares are around £50 all 4 and if I manage to do a back cut I guess I should get at least few extra lbs of torque....or at least feel better

 

My question is shall I do a back cut on new plasma heat treated valves?

Edited by Inno, 13 November 2018 - 03:35 PM.

[Turbo Phil]

You obviously misunderstood my reply before. The valve you linked to is the stainless race type valve. These already have the correct head/seat profile with the back cut, but are almost twice the price of the standard road spec valves. The road spec valves can be modified with a back cut to produce similar results, especially at the lift and rpm you intend to use. You can also retain the iron guides if you use the road spec valves, again much cheaper.

Phil.

[Inno]

You obviously misunderstood my reply before. The valve you linked to is the stainless race type valve. These already have the correct head/seat profile with the back cut, but are almost twice the price of the standard road spec valves. The road spec valves can be modified with a back cut to produce similar results, especially at the lift and rpm you intend to use. You can also retain the iron guides if you use the road spec valves, again much cheaper.

Phil.

now is clear!...thanks ...

[Inno]

I am spending most of my time reading available materials regarding possible "fast road" engine specifications and add on parts. 

 

I have pressed steel rockers with 1,27:1 ratio. I don't want to spend few hundred pounds on a new rocker assembly but I am considering off set bushes.

 

I found few threads about that but not any real solution for rocker posts. If I go 1mm offset I can gain 1,36:1 ration which sounds perfect for my new AC RS cam and what I want from the engine. I do not like to do that without moving posts or rocker shaft further toward lifters - to get rockers right at the position above lifters and valves.

 

I guess I can bore a bit wider holes in posts and move them toward lifters but I am not sure if it can work like that (sounds too easy)...would like to avoid any possible movement of posts over the time.

 

Is there any practical solution to that problem?