YBT cozzy mods for NA application

[RS Eskie]

Hi guys, I am looking at swapping out my YBT for an NA conversion. Without porting, valves etc Can you put NA cams suited to the hydraulic lifters say 1500-7500rpm into an unmodified head that will work with the standard size valves AND in the future work with larger valves porting etc when I can afford to do so?
i want to get it setup and going and use in NA form before doing any head work etc but don't want to have to go through the expense of getting new Cams again just because I want to go bigger valves if that all makes sense??
thanks Jonny

[trampbar]

It's better to use solid lifters for NA engines.
You can convert the hydraulic lifters you have to solid, that's what i did.
It wasn't expensive to do it, less than a hundred quid.
Regards
Brendan

[wildo105e]

Don't waste your money sell your ybt and buy a good modern na engine instead. Na cossy is not a cheap engine and results aren't world beating

[Forest_rallying]

As above, we did all that and bought the T shirt with the NA Cosworth engine in the early 90's. The best thing about that engine is the cam cover.

[RS Eskie]

Thanks for the advice fellas, but if you were to pretend that you were starting over in the 90's with all the knowledge you have now what is the winning combo for a fast street motor?

[Graham]

build a pinto! a lot cheaper and just as fast unless you spend extreme money

[MegatronUK]

1990's and normally aspirated? Got to be an XE if that's the case, imo. It's basically a normally aspirated Cossie already.

[RS Eskie]

Ok ok so what you are trying to say is, sell and build up a pinto or go more modern!

[wildo105e]

If you have a YBT now i am sure you will be very disappointed with a NA cosworth. I see what you are asking by trying to modify it in stages. The cosworth head is a turbo head and needs a lot of work to give any sort of power without the turbo. from your YBT about the only things you manage to keep will be head casting block crank and rods the rest will be new and the head will want a massive amount of work on the ports etc for what 220 BHP ?? without all the work required I was once told by an engine builder maybe 160-170 and none of the that lovely turbo torque.

Look what you can get out of of a pretty standard duratec 2.0. Induction/exhaust are still on the same side etc makes life easier etc.

stick with the YBT

read this it is a great source of info etc.

http://www.turbosport.co.uk/showthread.php?t=627342

[Erikmex]

Build a big cc duratec or XE 2.2 - 2.5 depending on budget, I'm guessing your Ybt car will have all the rest of the gear to suit big power, no point wasting it

[Forest_rallying]

One thing we learnt back in the 90's that the NA Cosworth is a very expensive engine to extract any power and torque out of, especially in two litre form.

A Duratec would seem a better option in my opinion but even then you are going to be into big money. There's no cheap and easy way to get power out of a NA engine. Why are you wanting to change from Turbo to NA RS Eskie?

[RS Eskie]

I completely agree about the expense for the cozzy build, the current ooodles of power I have now will be missed but I had a plan to sell the YBT and drivetrain (have a bare bones cozzy engine available to go NA on)to fund the body/interior as its bugging me now, it's not massively bad or anything but panel and paint are on the list for sure. I was going to go back to the pinto, type9, and escort diff after the spruce up till my zero budget recovered a bit, but I thought what would be better under the hood, a 150-160hp pinto or a 150-160hp cozzy? My brain says cozzy it!

[Graham]

so build a 170bhp pinto! seriously a ybt head flows no better than a pretty average big valve pinto, to actually make the ybt head flow you have to take a serious and i mean serious amount of metal out the ports a bit of polishing and short turn reworking wont cut it, even once you have done that you need to get the compression up and change cams

a vauxhall xe head as standard flows about 50% more air then the ybt, which is why that engine can give close to 200bhp with NO internal modifications, where as the ybt needs a shed load of cash to make 200bhp if you take the turbo off

[wildo105e]

Just to add, selling your YBT may not be enough to fund a N/A cosworth. You have probably £600 in pistons alone, head gasket, new flywheel for type 9 clutch, cams, vernier wheels, followers (16) exhaust manifold ? £600 , inlet Carbs or throttle bodies, ignition £2000 at least. The list soon adds up trust me i have looked at this since the 90's and although they look brill in the engine bay the cost spirals.

XE it or get a duratec there must be loads over your way a reliable 200 bhp

Your heart says cossy

If you do it make sure you start a thread whichever route you take