20 Valve Blacktop Race Engine

[takai]

If revs kill VW boxes, then how do the Formula V's get away with it? They do silly revs....

[Ben Wilson]

Bugger all load, FVs weigh nothing and don't have the shock loading of the off road tyres.

[takai]

Yeah, im just arguing with this simplistic view of thigns:

Revs is the problem because revs create the heat that destroys kombi boxes

Sure revs generate heat, same with T50s. But its quite managable with coolers and with regular changes and a larger oil capacity.
What Ben Wilson has brought up is the real reason why a VW box wouldnt cope overly well, not simply 9000rpm....

[Trekka273]

Yep, the Albins 'boxes are very expensive. There are a few used ones floating around for sale now for around $13,000 tp $15,000... a hell of a lot for a second hand 'box, and they are very big and heavy.

Ben and Takai are right, it is not the temperatures that hurt the VW 'box, it is the shock load on them. Our previous 'box ran an oil cooler, top of the range Castrol synthetic oil and we also had a temp gauge so we could keep an eye on it. Temps were never really a problem. With a full set of Albins gears in it, super diff, etc the 'box managed to survive, albeit with a strip after every race for checking.

Ben, thanks for the reply on the engine. That is what I am aiming for, an engine that has a good, usable powerband. I don't want a motor that has nothing until 8000RPM, hence why i am looking at the smaller cams rather than 300+ cams. There is a lot of stop start type work in off road, and there is more time to be gained there than there is in outright speed along the straights. We never lacked in top end before, and I don't think that will be a problem now. The biggest thing is to get out of the corners as quickly as possible.

I finished stripping the blacktop yesterday. My only real concern with it is the size of the rods. They are very light. I think I will be definitely changing these... Any suggestions for some decent, not too expensive rods to suit?

[Billzilla]

If revs kill VW boxes, then how do the Formula V's get away with it? They do silly revs....

Sarcasm?
I think they're lucky to get much more than 5,000rpm odd. They're all of a raging 50hp or so mate.

[takai]

Sarcasm?
I think they're lucky to get much more than 5,000rpm odd. They're all of a raging 50hp or so mate.

Some of the guys over here are doing 8000rpm through theirs, no sarcasm.

[takai]

I finished stripping the blacktop yesterday. My only real concern with it is the size of the rods. They are very light. I think I will be definitely changing these... Any suggestions for some decent, not too expensive rods to suit?

Yeah, the stock smallport rods will be all you will need. If you can break a set of those in NA form you will be doing very well.
ARP rod ends though

[Ben Wilson]

I finished stripping the blacktop yesterday. My only real concern with it is the size of the rods. They are very light. I think I will be definitely changing these... Any suggestions for some decent, not too expensive rods to suit?

Just because they are small, doesn't mean they are a liability. They might only be small in places where strength isn't needed.

Has any body heard about anyone* breaking a rod in a blacktop?

* - Apart from a certain individual who's name won't be mentioned...

[oldcorollas]

Just because they are small, doesn't mean they are a liability. They might only be small in places where strength isn't needed.

Has any body heard about anyone* breaking a rod in a blacktop?

* - Apart from a certain individual who's name won't be mentioned...

10,000rpm compression lockups will do that

hmm.. many people simply change them, but i can't remember of anyone actually breaking one.

i wonder if anyone has a pic of the 3SGE BEAMS rods vs stock... they are meant to be lighter and can handle the stock high rpm.. so 'they' say.....

then again... if rods are the weakness inthe engine... it might pay to overinsure in that regard? (the common train of thought)

[Trekka273]

That is probably the thing. They may not be a problem, but they look so small, I would just hate to think of spending all of the money, running it, have a rod break and then curse because I had thought about changing them.
I guess they do have the benefit of being lighter than the other 4AGE rods, meaning they should spin a bit easier, but are they too light?

[Ben Wilson]

If you want to swap them for a set of silvertop rods, I'm willing to take the chance.

[Trekka273]

Are the silvertop rods in good condition?
I might be interested, I have to have a bit of a look around first though.

[Ben Wilson]

There in a motor which the valve seals died in, so I assume there is nothing wrong with them. I've never had them out and as far as I know the've never been out.

[Trekka273]

I will have a think about it and have a look around and let you know Ben.

[Ben Wilson]

No worries.