Ridgey

iTrader: (5)

What spark plugs are people using when converted Cosworth to COP running 400-500bhp? Also what gap you have been using as well.
I've been getting some missing.
Thanks

20/20 vision

IK27 with 0.7mm gap driven by toyota yaris coils never missed at all on my car at 35+psi.

ive not actually tried openeing them up from 0.7mm and it may also be the case that other coil types may be incapable of firing 0.7mm gap or can fire larger gap

scoooby slayer

iTrader: (4)

I think thats what my last saph had in it, mapped by msd to 2.2 bar on a T4, 472 hp no ignition issues

Caddyshack

Mine is same as 20/20

Ridgey

iTrader: (5)

Thanks guys, I'll try as set of those.

20/20 vision

incidentally, for anyone considering going COPs, the yaris COPs are easy to fit and a no brainer if you value performance above originality and have aftermarket ecu

there are several yaris / toyota coil types which look essentially the same but with slightly different lengths / fittings and i found the easiest to be those with part number ending in 19021 or 02240. however, ive heard that other toyota coils which are longer do not require machining the cam cover turrets. Toyota yaris coils have built in ignitors so will work with any aftermarket ecu.

1) machine the plug turrets in the cam cover down to 3mm from the original 20ish mm.

2) fit the cam cover temporarily on the head, sit the COP in onto the plug top and mark the cover centrally where the COP's 7mm mounting hole is - a tiny bit of filing of the plastic on the COP body is required

3) remove COP and drill a 6mm hole in the cover and insert an m6 bolt from 'inside' the cover with a flanged m6 nut on the outside. use locktight.

4) there is a spring inside the lower region of the COP which connects the HT from the COP to the plug. remove the COP lower boot and stretch this spring 10mm then refit. this way the machined heights of the turrets and the thickness of the flange nut is irrelevant because the stretched spring will compress to accomodate variations and still make contact.

5) fit COP in again onto protruding bolt sitting it onto the flange of the nut then put a washer and nyloc on the top

job done!

connectors available from brands hatch on ebay and dwell is 3ms @ 13.8v (others may use different)

Caddyshack

I have a black cam cover that has had the turrets done for the Yaris plugs that is spare

Ridgey

iTrader: (5)

I'm running the other option that many go for, civic type-r coils

Caddyshack

Do you have to wait for the vtec to kick in lol

M K

iTrader: (9)

I run Yaris coils

Machine turrets down, flip rubber washer on coil upside down and bolt coil down using original Cosworth m6 bolt hole

Didn’t have to drill or tap andything and didn’t need to stretch the coil spring to reach the plug

Job done

Adam-M

Mark that is a seriously impressive car

stevieturbo

I think the Honda coils are a fairly simple fit too ?

And always use genuine OEM coils...aftermarket are usually rubbish

Ridgey

iTrader: (5)

There are little fitting brackets available from BHP.
I wanted mine in line so drilled and tapped cover, and made a small post to support.

jonfoc

markk

iTrader: (2)

Denso coils, no machining, no drilling, no tapping of anything.

20/20 vision

most of them are denso - which particular denso coils are your referring to?

Ridgey

iTrader: (5)

The civic typeR are Denso.

stevieturbo

I think it's the K series ?

099700-0430

markk

iTrader: (2)

Can never remember the number but they are from a type R civic.
Had them on for maybe 5\6 years now. No bother.

Ridgey

iTrader: (5)

Yep. Same ones by the looks of it.