Skip to content
Aussieveedubbers

Race fuel and boost

0 likes
Share Share on Facebook Share on X Share on Reddit
Log in to reply

Performance Upholstery Officially Full-On Dubber

229 posts · joined Nov 2013 ·

#996235
Hi guys, just wanted to throw it out there as I think I might me wasting my money using a 105 unleaded race fuel for my application... It's great fuel but I'm wondering if I even need to use it at this stage. Until I am ready to run a 10, have my car inspected and get all the relevant safety gear involved with super sedan. My engine will comfortably make the 200 ish hp required to run low 11's at only 10-12 psi boost. I'm running 7.5:1 comp.

The question is, could I be using 98 octane pump fuel?? Is the race fuel overkill for 10-12 psi???

Thanks in advance.
Mick
Performance Upholstery
Cars, boat seats, furniture and more!
0439002870
performanceupholstery@live.com.au
Mt Gravatt east Qld.

ian.mezz I never said, I could write or spell

3,913 posts · joined Sep 2004 ·

#996245
roses little nude bug street motor gains 20hp with 102 compared to 95 pump gas , we have the tune to run both .
it allows an increase in boost without fear of detonation.
😂🤪😂🤪😂
car forums. where a lot of peoples good intentions end up taking a good old car off the road forever never ever to see the road again. 🥲

lou0060 Wolfsburg Wizard

568 posts · joined Dec 2010 ·

#996261
Hi Mick, is the 105 you are using my blend or VP or other? the higher octane allows you to run a bit more advance. 98 is pretty good when you look at the dollars side of the equation but you will sacrifice some advance and so some hp.

For the record my 105 unleaded has some oxygen in it so works well with turbos which like a bit of oxygenation in the fuel.

in terms of compression ratio 105 is definitely over kill as generally 105 is aimed at around 10:1, obviously add boost and that changes the equation a bit but in the end you won't know the real answer unless you do back to back runs on a dyno.
1971 karmann ghia Cabrio - Cruising 👍
1963 beetle Sunroof - gathering dust 🥲
1968 race beetle - twin turbo Subaru - stress relief 😁
1960 beetle - old school low & slow 😏

Performance Upholstery Officially Full-On Dubber

229 posts · joined Nov 2013 ·

#996290
Yeah lou, it's your fuel. Don't got me wrong. It works great and I'm really happy with it but I was just wondering if I really needed if at only 10 psi. But to be honest, we are about to up the boost a little and put a heap more base timing in so I'm probably best to stick with it. Thanks for the advice. If cleared it up for me a bit. I understand what the fuel actually does now.
Performance Upholstery
Cars, boat seats, furniture and more!
0439002870
performanceupholstery@live.com.au
Mt Gravatt east Qld.

55slug Seriously Crusin Dubber

169 posts · joined Jul 2006 ·

#996498
Just another option (I'm running with this). 98 and water/meth injection. I'm doing a pre turbo set up from Greene Bros here. Just for reference, they run a 13b on 98 and pre turbo injection, 40psi boost, 850hp,8s and street driven.
Don't know how this would work in a draw through set up though.

lou0060 Wolfsburg Wizard

568 posts · joined Dec 2010 ·

#996583
I guess it is all about how complex you want to make it. Anything hitting 850hp is a serious bit of kit, like they say "lots of ways to skin the cat."
1971 karmann ghia Cabrio - Cruising 👍
1963 beetle Sunroof - gathering dust 🥲
1968 race beetle - twin turbo Subaru - stress relief 😁
1960 beetle - old school low & slow 😏

55slug Seriously Crusin Dubber

169 posts · joined Jul 2006 ·

#996596
It's a mechanical system, pressurises tank with a feed from the turbo, feeds the nozzle on one side, air the other, one solenoid, just need a pressure sensor to switch the solenoid on at desired boost levels. http://wannaspeed.com/home/8-mechanical-water-injection.html
There's some evidence out there that pre turbo injection erodes compressor blades, but I'm willing to take that chance.