Pinto Cam Timing confusion

[LewisH]

Hi all,

I currently have a 185 block pinto with a fast road cam (not sure on exact cam make or model), I am also reconditioning a 205 block pinto, which will also have an uprated cam.

In order to perfect the cam timing, I thought I'd get a DTI guage and experiment on the 185 block. It's currently installed I'm the Exmo so access isn't great, but doable.

So I started with reading up on the several threads on here and other forums, found that the overlap method of working out the correct inlet cam lift was best. 

I am now a bit confused, because in it's current setup at TDC, both inlet & exhaust valves are closed...is this right? The car starts and runs OK.

If I set the inlet valve on no1 cylinder full lift @ 108 deg ATDC the engine won't start and spits the fuel out of the carb rather than drawing in.

Obviously this is wrong, but not sure what I am doing wrong. I am measuring the valve lift from the spring retainer top, is this right?

When setting the valve lift, do I measure this from valve fully open or fully closed?

I've ordered the Des Hammil tuning guide but currently out of stock, any advice in the meantime would be much appreciated. 

[tractor]

the lift is measured from top of cam lobe your dti gauge will measure your cam lift and get the cam to a perfect TDC then your adjustable cam pulley is where you fine tune yes at TDC on number one cylinder both valves are closed on a pinto it will spark at 10 degres before TDC 

Edited August 7, 2022 by tractor

[Sparepart]

You had another thread "Pinto injection head identification", in that thread I posted a link to download a pdf tuning guide, the author of the guide is Des Hammil, perhaps it's the same manual that you have ordered ?.... anyway here is the link again .... when you see it on screen it looks like you can only view it on line, but hover the mouse on the text and a tool bar appears at the page bottom, in this bar is a "download pdf" option.

https://procarmanuals.com/pdf-online-how-to-power-tune-ford-sohc-4-cylinder-pinto-cosworth-dohc-engines/

 

[Jez Morton]

Two things I might suggest based on mine own mistakes.

1 Is the CAM 180deg out? Crank turns 2x CAM.

2 Timing marks are before TDC, maybe you need to go 108degs the other way

[LewisH]

Thanks all. 

Yes cam was 180deg out, also set it on the exhaust stroke rather than compression which didn't help.

Set it up correctly this afternoon and sounds great, tappets were also badly in need of adjustment which has also helped massively. Never realised how noisy it was before until now.

Glad I experimented on the 185 first!

Edited August 8, 2022 by LewisH