Tiny turbo on Mk1 hillclimber, is it pointless?

[RhysQ]

Hey guys,

My mechanic (an absolute VW nutter) is soon building his 8v Mk1 into a proper competition hillclimber, fully stripping it, rollcage, race seats, perspex windows, engine mods etc etc.....the works!

His mate who is a jap imort mechanic has a small (well...tiny) turbo laying around from a Honda Cappucino or Diahatsu Copen. He wants to put it in the Mk1 for a little extra kick. I am looking to upgrade my intercooler soon and said he can have my stock side mount cooler if he wants. He intends to front mount this.

Is he wasting his time with such a small turbo or do you think this will be a good plan for its intended use? Will the tired 8v handle the extra power? Keep in mind this will by no means be a daily driver. Also, he is not chasing breakneck power but just wants a little more than the stocko donk has to offer.

Please don't bother with comments like "get a T03/04" or "vortec supercharger FTW" . He only wants something small that he can build himself.

Thanks in advance guys,
Rhys

[Jarred]

I'm not a turbo expert, but I'm pretty sure it'll be too small.

Those engines are 1.1, 1.3's? aren't they?

Also what size 8V is he building up.

Alot of things will have to be considered about the turbo, given it's current trim etc.

I hate to say it, but a T3 off a saab 9000 would be much better, interms of stock sizing's and flow capacities. I think the small turbo may 'run out of legs.' with the lager capacity/flow of the bigger engine.

Just my opnion, based on my very basic turbo knowlegde, happy to be corrected

EDIT: also will he be disadvantaged for running an additional power add on? I know for sprint classes, like Pete Jones is running in, and many others, turbo cars have their capacities timesd by 1.7, I believe, that way a 1.8T will end up competing against 3L cars. Just something else I thought I'd add. Point being: check the hill climb reg's first

[WABIT]

there are diffrent classes with hill climbs, there is usually a 0-2.0lt class and a 2.0lt and beyond, most of those hill climbers are worked 1.6's

dom

[evorobin]

Yeah FA is X 1.5 or somethiing

Joel supercharged his 1600 mk1 with a toyota blower. No faster than an 1800 valver to be fair...

[madglf3]

Suzuki Cappuccino and the Copen are both 660cc, so it would be tiny as mate.

[Preen59]

Torque is a MASSIVE factor in hill climbing. You don't need mountains of top end, and infact a lot of the time it's pointless. Good mid range and bottom is far more essential.

In this case he would probably only want to rev the donk to 5,5 or so. It would have boost almost at idle and would be great for short tight hill climbs.

All this crap about needing big turbos is pointless for that.


(I'd prefer to use a blower, but hey, that's just me!)

[RhysQ]

Cheers for the comments guys, much appreciated. Will pass all this on. And yes, SUZUKI Cappucino, haha my bad, not HONDA.

Also what size 8V is he building up.

It's a '76 LS, 1.6L as per redbook.

In this case he would probably only want to rev the donk to 5,5 or so. It would have boost almost at idle and would be great for short tight hill climbs.

Yeah that's why he just wanted a very small snail from a factory turbo car, because they are usually designed to come on boost very early in the rev range.

Maybe the Cappucino or Copen Turbo will be too small, seeing as its from a 660cc engine.

His main focus is to get the thing breathing a lot better so it's responsive in the low end.

[evorobin]

Most cheap aftermarket mani's are for a garret so T25 might be the go. Having done a hillclimb myself I agree with the comment about torque but having top end = less time consuming gearchanges also.

[RhysQ]

in using a small turbo with the 1.6L 8v would he need to upgrade any of the internals?

sorry if any of these sound like dumb questions, i dont really know that much about the mk1's . I'm gonna help him build it so i can get some know-how when I start one up somewhere down the track.

[Jarred]

depends on how much boost he runs.

If it's a strong engine, i'd say atleast 7psi, up to 10 psi perhaps. Not sure too many people here would have turbo'd an old 1600. It'd be fun though!

[WABIT]

there are alot of factors before internals, firstly how about fuel system? u going to keep it carby? or injection?

dom

[RhysQ]

there are alot of factors before internals, firstly how about fuel system? u going to keep it carby? or injection?

dom

i'm pretty sure he wants to keep it carby. how do you uprate fuel supply with a carby engine? i was wondering whether that is an issue.

[Jarred]

i'm pretty sure he wants to keep it carby. how do you uprate fuel supply with a carby engine? i was wondering whether that is an issue.

it can be done. very popular among street machiner's.

This is for a blow through setup!

the carb will have to be rebuilt and modified to operate under pressure (ie boost}

Then you have a big carby fuel pump, with variable fuel pressure thingy (forgotten the name}. ie when boost comes on the fuel pump pumps more pressure. 1 pound of boost = 1 pound of fuel pressure {extra}

and you just use the standard dizzy but swap the advance and retard around, so that the dizzy advances when boost hits.

It's a relavitely simple set up, but would work. and note, this is a simple explanation of the required set up. I don't think I've missed anything specific out.

It's also not nessecarily cheaper than FI either. cost can be similar, FI would be easier to tune imo, less fiddling with different jetting etc etc. I can recommend someone for your mate to talk to if he's serious about a blow through setup.

A draw through setup could be a bit easier, as there is less fiddling with carby mods. Draw through isn't as efficient and generally can only run lower boost/power levels. This was covered a while ago, I'll see if I can find the thread.

here: http://www.vwwatercooled.org.au/newf...ght=draw+turbo

[RhysQ]

cheers Jarred, i'll have a chat to him about it and see what he wants to do.

[Sharkie]

I'd go for a SC-12 off a Toyota 4AGZE motor. Can be had for $350 off ebay. No need for a turbo manifold and simple to fit mechanically.

Since its off a 1.6 anyway should be perfect for a 1.6 Mk1