15 replies to this topic

[alexcrosse]

Got a 286 kent cam. I need to no the exhaust and inlet lift @ tdc... Proving difficult. Is there anywhere i could get circular diagrams from??

Cheers.

[roofless]

Got a 286 kent cam. I need to no the exhaust and inlet lift @ tdc... Proving difficult. Is there anywhere i could get circular diagrams from??

Cheers.

didnt they come with the cams? you aint having much luck with stuff missing are you

does this help?

http://www.theminifo...showtopic=36988

[alexcrosse]

at TDC is the inlet and exhaust equal?

[Sprocket]

The Kent web site will give you this information

[Ethel]

Very much doubt it. I'm puzzled as to why you want this info???

[alexcrosse]

they dont seem to say full exhaust lift at tdc. Well i think its obvious? i dont want my pistons to hit my valves. since i have a 1.5:1 rocker set, 11.5:1 cr, very little combustion chamber, and the exhaust is going to be open more at TDC than inlet surely.

Already been on kent.

Can someone tell me is the exhaust and inlet is equal at TDC?

[v8mini]

at TDC shouldn't they both be shut whether on fire stroke of not. so no lift for either

[Ethel]

I can't see either valve coming anywhere near the pistons at tdc. Is the cam in the engine yet? you could work out what lift would have to be to hit the piston and then measure the lobes to see if that point is anywhere near.

It's a common choice of cam so someone must run it with 1.5's before now surely?

I'm sure you'll be doing a dry build? Try a blob of plasticine on the piston without a head gasket for peace of mind.

[alexcrosse]

at TDC shouldn't they both be shut whether on fire stroke of not. so no lift for either

ive worked it out now from halving the duration and and adding it to the max lift on exhaust. Im safe. But they are open at TDC simon... spark isnt at tdc anyway.

Need beer and sleep

[Ethel]

From a quick thumb through Vizard even a 300 degree race cam would only have 60 degrees of lift on either valve at tdc. But, to throw a spanner in the works, would the valves open and shut faster than the piston moves down the bore??? Could be if they were gonna meet it wouldn't be at tdc!

It makes my head hurt too much so, I think I'll stick to dry builds.

[alexcrosse]

60 degrees and tdc? that makes no sence atall.

[Ethel]

According to Viz....

AEG 596 - 320 deg Super Sprint

Ex closes 55 deg after TDC

In opens 60 deg before TDC


643 is the Abingdon cam with 288 duration

Ex 39 after, Inlet 34 before (Max lift 110 ATDC)

[alexcrosse]

According to Viz....

AEG 596 - 320 deg Super Sprint

Ex closes 55 deg after TDC

In opens 60 deg before TDC


643 is the Abingdon cam with 288 duration

Ex 39 after, Inlet 34 before (Max lift 110 ATDC)

yer, 60 degrees before tdc, not at, lol. I no, well thats just vizard phrasing things badly as per usual. basically i worked it out. I was worried about the distance it would be open at tdc. But it seems alrite. Ill turn it over slow with no plugs etc. Have a GOOD look. And see how it goes. I just really wanted to check, not running the original 314 cam, running a 286 with 1.5:1's which would gimme a higher exhaust lift, and i got a really shallow chamber and skimmed omegas since its a 1430, so not much room in there!!!

[Ethel]

Makes sense to me (I think )

Inlet opens 60 degrees before so at TDC it will be roughly a 1/3rd of its way to full lift (by cam rotation and somewhat less in terms of actual valve lift). The Exhaust is doing much the same in reverse.

[alexcrosse]

Makes sense to me (I think )

Inlet opens 60 degrees before so at TDC it will be roughly a 1/3rd of its way to full lift (by cam rotation and somewhat less in terms of actual valve lift). The Exhaust is doing much the same in reverse.

but its not linear. and u just said 60 degrees at TDC, thats what i was on about. Roughly yes, i should be fine! ill just wack the head on and turn it over. Should be fine. 286 is 180 degree apposed (in and ex) and working it out the valves SHOULD clear. But it sayes silly things in the kent manual like, must be .016 clearance, then doesnt tell u lift at TDC! lmao. Ah well.

Cheers, guys.