I'm after some opinions on a setup I'm thinking of running and what you all think, i.e performance whether something isnt suitable and whether I should think of additional changes.

 

Currently i have a stock 5k in front of a 4 speed and this is my plan. Use will be a bit of a weekend fun car, not a cruiser or anything. Bit of fun action in the dandenongs on the weekend!

 

Engine

Tighe 104 or similar

32/36 Weber rejetted to suit other mods.

Get some extractors at some point after this also

 

Driveline

Getting the flywheel lightened with a HD clutch

k50 behind this just for the overdrive

 

So if anyone has suggestions of anything else i should do or not do that would be appreciated

 

Thanks

Set of uprated valve springs as recommended by Tighe for lift over 0.400".

 

Maybe shave the head for some more comp, but I'd only bother if I was taking the head off for some other reason ie valve grind or something.

Set of uprated valve springs as recommended by Tighe for lift over 0.400".

 

Maybe shave the head for some more comp, but I'd only bother if I was taking the head off for some other reason ie valve grind or something.

 

I presume valve springs would be something that tighe would be able too supply aswell?

 

I was considering taking the head of just to give the head a clean and suss the condition of it. If it was looking a bit ratty i was considering getting some head work done i.e porting, shaved head and also bigger valves if there is a standard sort of big valve upgrade.

Yes Tighe could supply springs.

 

This is what I would call a "fun daily" list of mods, its nothing remotely serious at all. Hence forget about bigger valves - for what it'll cost you the other mods just don't support it.

Port and polish for sure.

Yes Tighe could supply springs.

 

This is what I would call a "fun daily" list of mods, its nothing remotely serious at all. Hence forget about bigger valves - for what it'll cost you the other mods just don't support it.

Port and polish for sure.

 

Sweet, thanks for the help. I reckon i'll do the head for sure then, just to get some better airflow with the exhaust and bigger carby

Basics sound good.

 

Hook up a 2" exhaust, and an electric fuel pump (made a difference on mine). Definitely up the compression, 5K's love it.

I'm guessing you had upped the compression in your 5K(s) Coln72, just out of interest, how much did you have taken off the head and what CR was it at? Considering having a small amount taken off mine while my car is off the road at the moment. Just like to know how much is enough to take off :bash:

Basics sound good.

 

Hook up a 2" exhaust, and an electric fuel pump (made a difference on mine). Definitely up the compression, 5K's love it.

 

What sort of compression can a 5k run, or is best suited too? given that i will be running it on optimax or a similar 98 octance fuel.

 

Given that how many thou should i get skimmed to achieve that?

Talk to the guys that are going to machine your head. If they are anygood (the company that did mine build race motors), they will recomend how much to suit your requirements. If they can't, walk away.

 

Can not give you any specifics as it was 10 or so years ago, but it was shaved to give the max. compression that I could run using pump fuel. Made a big difference - from stuggling to climb a lcal hill in fourth before the rebuild to accelerating in fifth after it. And no, the motor wasn't stuffed before the rebuild. We were chasing a knocking noise when it was stripped that turned out to be a cracked inlet manifold.

Awesome, thanks for that info Coln.

 

Regretting not doing it earlier when I was building the engine, but I guess it can't hurt to find out about it from someone in town now.

I recently read that compression ratios should be 1/10th of the octane of the fuel you plan to use...

 

So 9.8CR for street use in old Toyota motors.

 

Is there an SU carb around that we can use as a set of twins on our 1300/1600 motors?? Something that ran up to the 90s before everyone went to EFI. I reckon it would be easy to make a few inlet manifolds and sell them through the club if we could source some twins to put on. Much better than downdraughts!

With compression it is really dependent on the cam you run. If you run higher than ideal CR you have to back down the timing which leads to below optimum performance and makes a motor run flatter than it would if the CR was matched to todays fuels.

 

The best all round carb for a k series motor is a 28/36 DCD weber (especially a 5k). A downdraft. :bash:

 

Have a read here paying attention to TepiTheFinns posts. He is running a 36/36 DCD weber where both throats open together. LOL, not much difference to sidedrafts.

 

With the 28/36 DCD you have primary/secondary opening which works much better in the low end and is better for economy/drivability.

Yeh the valve job will cost a overrated. They are very close as it is so you'll struggle to get any better in there.

 

I'm running about 11:1 but the main reason I have it that high is because my new ACL pistons had half the dish from the original ones. After much deliberation about what to do, ie getting the combustion chamber in the head opened up etc, I decided..... Screw it, filled her with 98RON and off I went. No troubles.

 

I have a reasonable cam in it though, so my dynamic compression is lower, I would be nervous about running a stock cam with that compression.

ok all sounds good.

 

I guess a compression ratio up at about 10 should be pretty good hopefully, just as a query, what is the stock compression

 

I will be running this with a mild cam and 98RON all the time so i hopefully wont have an issue with detonation if i raise the compression.

 

What cam are you running Philbey?

Mystery Special I bought of kangaroosa, he wasn't too sure and I couldnt find a stamp on it. I have plotted the cam profiles using a dial gauge, but I need to redo it because I didn't do it well enough.