Engine options for a Hill climb car...?? is TDi an option??? - Page 5

marcz · 16-10-10, 12:06 AM

A STANDARD 20V engine?

Turbo lag is only an issue if you can't drive and can very easily be reduced by various means. Well planned plumbing, appropriate size intercooler, decent recirculating dump valve and some anti-lag will sort most of the problem, especially on a 'tame' engine. Even the simplest aftermarket ECU will provide you with channels for anti lag control and maybe even launch control. It's not an expensive route to take either.

Both NA and forced inducted engines suffer as they are pushed up the power output range. Your NA motor will need carefully thought out gearing to maintain useful power as the 'area under the curve' is compacted. The similar turbocharged engine will deliver more power over a greater range.

My NA Datsun developed it's useful power between 5000RPM and 7000RPM... pick the wrong gear (see the video) and it was far worse than a turbocharged car caught 'off boost' or 'turbine stalling' in a gear change.

230hp would not be a big ask of a £50 KG engine! Throw some money at it, let's say the cost of throttle bodies, head work and an ECU for a NA motor, and you'll have way more tractable power on tap than you will ever get out of the NA version!

Hamish · 16-10-10, 08:04 PM

I would have to agree with the above.

A highly tuned N/A engine can be very peaky and only produce the goods right up at the top so in a way can have more lag than a turbo engine. Yes you might be able to make 220bhp the same as a 20vt but thats going to be the only time it will have matching numbers to the turbo engine.

A 20v turbo with a re-map will give a huge spread of power and torque so its not so important to be in that last 1000rpm of rev range.

BIGGYIN · 16-10-10, 08:18 PM

and it makes,alovely sound.

styler · 16-10-10, 08:50 PM

glad ya didnt cave in to the oil burner brigade.....

16-10-10, 08:18 PM	#43
BIGGYIN 4 ring whore! Classic Audi Club Member Join Date: Mar 2009 Location: Merseyside Posts: 7,976	and it makes,alovely sound. __________________ q90 B2 Type 85 - q90 B2 Type 85-PROJECT-ABY 20vt KARL. Injection is nice but I'd rather be blown

16-10-10, 08:50 PM	#44
styler Moderator Classic Audi Club Member Join Date: Jul 2009 Location: Donegal, Ireland Posts: 3,443	glad ya didnt cave in to the oil burner brigade..... __________________ CRASH VALLEY CUSTOMS get 'er done...

16-10-10, 12:06 AM	#41
marcz Grown up member Join Date: Oct 2009 Location: Towen Mountain, Queensland, Australia Posts: 953	A STANDARD 20V engine? Turbo lag is only an issue if you can't drive and can very easily be reduced by various means. Well planned plumbing, appropriate size intercooler, decent recirculating dump valve and some anti-lag will sort most of the problem, especially on a 'tame' engine. Even the simplest aftermarket ECU will provide you with channels for anti lag control and maybe even launch control. It's not an expensive route to take either. Both NA and forced inducted engines suffer as they are pushed up the power output range. Your NA motor will need carefully thought out gearing to maintain useful power as the 'area under the curve' is compacted. The similar turbocharged engine will deliver more power over a greater range. My NA Datsun developed it's useful power between 5000RPM and 7000RPM... pick the wrong gear (see the video) and it was far worse than a turbocharged car caught 'off boost' or 'turbine stalling' in a gear change. 230hp would not be a big ask of a £50 KG engine! Throw some money at it, let's say the cost of throttle bodies, head work and an ECU for a NA motor, and you'll have way more tractable power on tap than you will ever get out of the NA version!

16-10-10, 08:04 PM	#42
Hamish Grown up member Classic Audi Club Member Join Date: Jan 2009 Posts: 358	I would have to agree with the above. A highly tuned N/A engine can be very peaky and only produce the goods right up at the top so in a way can have more lag than a turbo engine. Yes you might be able to make 220bhp the same as a 20vt but thats going to be the only time it will have matching numbers to the turbo engine. A 20v turbo with a re-map will give a huge spread of power and torque so its not so important to be in that last 1000rpm of rev range.