43 replies to this topic

[Rosslin Racing]

thanks for the anwsers you have restored faith! apart from the fact this build has details that are
the BMW conversion must be in a mag this month couse I have been over run with question about this. Whos doings kits? can I do myself? how much?
the off set is good I like the idea, and that it remains a 1275. all that remains is to go look at the the real thing at SC.
thanks Sprocket for doing this thread and keep up the

[boulton6868]

Sprock - apologies for thread hi-jack!

regards pricing - the figure of £7k would be a full race spec engine ready to fit to the car complete with ecu/loom etc - you'd be pushed to get a 130bhp 5 port for that amount from a race engine builder and only a small amount of people go for this option as its rather extreme for the road.

The £2700 is a price for a wheelbarrow load of stuff to let you get on and build the engine, includes ecu/loom/ancills/machining etc - it depends how much you value your time. Its taken most diy builders between 6 months and 2+years to get their engines together. It takes me 3 days for an engine and gearbox build and assemble using our kits and parts, its horses for courses.

I reckon if you could do all the welding/machining yourself and buy an 8v bike, break it, sell the old parts off, use our conversion kit, put bike carbs on and a dizzy to a "fit" 1275 not needing a rebuild you'll get nearly 110bhp for under a grand thats the other end of the scale.


Spock - get it motoring fella - I have some ram pipes by the way if you need any

Cheers

JK

Hi just looked through your post very impressive,
i have a 1430 mini at the min and would like this head could you advise me on what you think it will cost and the parts i will need.

[Rosslin Racing]

Hey sprocket, what sort of compression are you looking at running, I see that your pistons dont have this massive cut outs that I have seen with others.

[Sprocket]

11.3 - 11.6 to 1

I say that as different people have calculated it and those were the numbers we came up with

The car is now MOT'd and running, dyno is booked for Tuesday

[Rosslin Racing]

compression sounds good, I have an RS head and at the start of the long road you have been down,
I see you used an MPI block, would you have choosen another block if you could have?

[Sprocket]

I had my reasons to use the mpi block, but in all honesty, it didnt really matter as those reasons were never realised

[Sprocket]

http://uk.youtube.co...h?v=sqbJhBPS6-w

Thats just the begining More to come soon

[Rosslin Racing]

i am all funny inside now after seeing that
makes me want to go into the workshop and not come out until i have done the engine.
the Mpi block is strong its the cranks that makes me worry.

[Sprocket]

standard cranks with the relevant mods are fine, dont worry about it. No need for fancey billet jobs unless you intend to stroke or destroke the engine

[Rosslin Racing]

what sort of RPM is possable with that set up?

[Sprocket]

I built it to take 9k rpm

already had it at 7k

[Rosslin Racing]

9k mmm I like......
What will the cams put max power out to?
went and looked at the other forum that Holt chappy loves his work too some real nice work I will have to ask him if he has that program for CAD to do the rocker cover on the milling machine.

[Sprocket]

Dyno session was yesterday and it was not without issues, nothing major, but mapping the ignition was aborted. there is a little more power (3bhp I would hope to take me to my lower target) to be gained in that area alone, or at least thats what my mapper tels me.

Also remember that the inlet cam is the lower lift shorter duration item, so I think the final results so far are on the money.

I think i'll bung the RS inlect cam in it before the dyno shoot out

107 bhp at 7300rpm and 81 lbft at 6400rpm.

It drives amazingly well, thats the bit that really matters and, if anything, I am at the same level as i was with the 1400, which is all i really wanted. I would have found it hard to accept if it was anything less than the 1400

Please please please excuse the swearing http://uk.youtube.co...h?v=aEPorptkRPs

[Rosslin Racing]

when you going to warp speed Mr sprocket?