5 replies to this topic

[ajac8]

My Son (on a whim) has brought a 1972 998 with some modifications. Most notably a 1293 engine! It a smart looking car with all the usual rusty areas having been sorted.

 

I have to admit however that I'm a bit lost with all the jargon and having searched the intraweb thing have decided there is just too much info to take in. I'm hoping getting a basic understanding the mods will help me understand what he has brought as I have to be honest he is loosing me a bit. 

 

I'm a simple bloke who like simple answers so I can understand the purposes of something therefore.....

 

Can anyone help me please in simple 'mini for dummies' english what the following mean?

 

1. 'Race spec big valve cylinder head'

2. 'fully flowed'

3. 'ported with all new valves'

4. 'Keith Dodd 1.5 forged rockers and double springs'

5. '286 Kent camshaft'

6. 'gearbox 3.1:1 final drive, with added centre oil pick up'

 

You assistance is much appreciated.

 

Cheers 

A confused Dad

 

[Spider]

Hi Confused Dad!

 

Welcome to the forum. We hope to also see your son along with some pictures of his recent purchase

 

In regards to the list of items that your son's mini has had done to it, I think the 1293 cc engine speaks for itself. Note that this is a completely different engine to the 998, ie, you can't 'bore out' or do anything else to a 998 to make a 1293 engine.

 

The other list if items done to the engine and gearbox are in the simplest of terms are 'hot up' or 'go faster' items, however, in my own opinion, some of these items also make the car a little less than friendly or easy to drive, they tend to make it something you really need to be a bit more on your toes about and be mindful of when driving, particularly, when in traffic. Others here may differ in their view, but that's my own experience. Not to be taken altogether the wrong or in a negative way though, it can make it fun.

 

<edit:- can to can't !!  DOH >

[timmy850]

I think Moke means to say: you can't 'bore out' or do anything else to a 998 to make a 1293 engine.

 

1. Bigger inlet and/or exhaust valves in the head. Bigger valves = more flow potential

2. Someone has modified the inlet and/or exhaust ports to allow more air in and out of the engine.This may mean they also measured the head on a flow bench to make sure it has been improved and the cylinders are reasonably even

3. Pretty much the same as 1 & 2

4a. Higher ratio rockers (e.g. 1.5 ratio) mean that you open the valves more, which should allow more air flow. 1.5 ratio rockers mean for 1 unit of lift at the camshaft you get 1.5 units of lift at the valve.

4b. Double valve springs are higher specification than the original single valve springs and close the valves. Weak springs = lower RPM potential

5. Kent is a company that grinds camshafts for more performance. A 286 cam is a more aggressive cam which favours higher RPM. 

6a. 3.1:1 final drive is a reasonably low final drive for a mini. The lower the number, the less RPM when at speed. Early minis and racing minis traditionally have higher ratio diffs (e.g. above 3.7:1) and later cars had lower final drive (e.g. 2.76:1) for less noise on the highway.

6b. Centre oil pickup changes where the oil is collected in the sump. Stock cars can have a problem with the oil sloshing away from the pickup during cornering, but a central one should keep it submerged in oil. 

 

[Spider]

I think Moke means to say: you can't 'bore out' or do anything else to a 998 to make a 1293 engine.

 

 

 

Ahh,,,, yes,,,,

 

Thanks Tim.

[ajac8]

Thank you gents this is most helpful.  

 

We pick the car up Saturday. Will post pics asap. I think I'm more excited that him!. Its a 1972 car so will no doubt have its challenges ahead - but hope nothing we can't handle. He sold a 2004 BMW Cooper because he considered it was basically 'boring' to drive and own.

 

My hobby is restoring classic range rovers so I know my way around a V8 but when it comes to race mods I'm a fish out of water. The Range Rover forums are great places and its good to see this forum is as well supported and helpful.

 

Our first task to to fix an horrendous oil leak which seems to be coming from the lower nearside (UK) part of the engine. It spills about a teaspoon of oil on the floor in 10 mins of idling so although the car is roadworthy and the (lively) test drive went well we are going to use a flat bed trailer for the 50 mile collect trip until we know what the issue is.

 

Thanks again and look forward to more posts.

[nicklouse]

that sound like the half moon oil seal or the timing chain cover.

 

the first thing I would suggest is one of the older Haynes Workshop manuals NOT the new dark blue service manual.

 

and then there are a number of Mini only tools that you will need.