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dumb question?
pete wood - January 26th, 2007 at 09:11 PM

Just spent the day at the holden vs ford drags at WSID. Great day and lots of very fast cars there. Makes me think.

The fastest NA VWs in OZ struggle to break 9 secs.

Yet the faster NA V8s are in the low 7s.

I'm not slanging out our serious NA racers (my hats are off to you), I'm just wondering what it takes to make cars do 7s, and why it is that VWs struggle?

Can Dangerous or Boostn help me out here? I love drag racing, but I have no detail knowledge about it.

boof2332 - January 27th, 2007 at 12:54 AM

i am sure the experienced boys will be more precise, however i will throw a couple of reasons out there..

Big v8's can make silly hp and naturally torque. There are also endless manual and auto gearbox/diff options to choose from that are strong, reliable and resonably priced. Combine that with a tubbed rear end and slicks..

Matt

xornge666x - January 27th, 2007 at 07:39 AM

A 1600 VW engine has around 60hp i think, a Ford 351C makes around 250hp(2v) in standard form...
I think a 4cyl aircooled car 'struggling' into the 9's is awesome.

shiftyvw - January 27th, 2007 at 07:43 AM

The V8's have just had so much more development done and are a better platform for making power. So comparing VW to V8 prostock style cars they have roughly 3 times the displacement, 4 times the hp and only 1.5 times more weight! do the maths! And there hasnt been a 9 sec NA pass in aus yet has there?

RAZ34 - January 27th, 2007 at 08:58 AM

The answer is cubic - dollars and displacement. Also check under the bonnet next time youre at a Ford/Holden day as the ony 'street' guys I know of in the 7sec zone N/A in Aust are Trick and Mansweto in their Capri .

vw54 - January 27th, 2007 at 09:13 AM

the simple answer is theres no substitute for cubic inches or capacity

If you could make a VW about 200 Kgs with a decent engine you could proberly break into the 7 or even 6s

Power to weigh is the answer

sean68 - January 27th, 2007 at 06:53 PM

Mark Hayes in the light blue LC torana runs a 632 cubic inch big block and 400 hp 2 stage nitrous kit.........he got 940 hp on the dyno N/A without running the nos at the last summernats

and he's driven it from castle hill to wollongong :duh

basically cubic inches and power to weight ratio is the key

pete wood - January 27th, 2007 at 09:18 PM

mmm, so how big does a type 4 in a beetle need to be to compete then?

Flintstones - January 27th, 2007 at 09:46 PM

Quote:
Originally posted by pete wood
mmm, so how big does a type 4 in a beetle need to be to compete then?


How about you reverse engineer the situation....

How much horsepower will you need to complete a 7 sec pass? my guess is lot more than the t4 could ever put out naturally. Going off the most common big bore and stroker kits you are looking at a 2.9L.
Have a look at Wanye's oval buildup and more importantly at the combination he put together to get mid 10's and this will start to show you what's required to even get to this level.....

Other questions to consider...
what final weight will the driver and car be?

What drivetrain arrangement will you be running for the car to be strong and reliable?

Cheers

shiftyvw - January 28th, 2007 at 06:52 AM

Quote:
Originally posted by pete wood
mmm, so how big does a type 4 in a beetle need to be to compete then?


Compete with what? have a play with this calculator

http://www.speedworldmotorplex.com/calc.htm 


It seems a fairly accurate guesstamate.

55slug - January 28th, 2007 at 08:53 AM

Crikey 777 hp at 1700lbs !!!

Might be a bit tricky to extract that from a VW NA !! I would guess with the revs required you would need 4 valves per cylinder and hydraulically operated valves ala F1... As for heads ?