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Technical => Engine Tech Forum => Topic started by: neil68 on February 18, 2014, 06:35:17 PM

Title: IDA fuel line size?
Post by: neil68 on February 18, 2014, 06:35:17 PM: More winter upgrade questions for the Beetle's 2332 cc engine with IDA's.

Is there any benefit for 1/4-mile drag racing, if I upgrade the fuel line size from the current stock line to perhaps 8 mm?

Currently running a Carter rotary pump (3.5 psi) and have a German 8 mm fuel tank outlet that I picked up a while ago, that I could use.

Any advice from your racing experience would be appreciated.

Thanks!
Title: Re: IDA fuel line size?
Post by: Bruce on February 18, 2014, 06:50:30 PM: The true test is to do a full ¼ pass down the track and shut the engine and pump off as you cross the line. Then after you make the turnaround, stop and get out and see if the floats are full or low. If they're full, your existing setup is not a problem.
If you wanted to do the upgrade, 8mm (5/16") is all any NA engine needs.
Title: Re: IDA fuel line size?
Post by: neil68 on February 20, 2014, 06:17:02 PM: Thanks, Bruce. That makes sense.

However, I was hoping to get some of this upgrading work done over the winter, rather than waiting until race season starts in May. Will ponder this some more...
Title: Re: IDA fuel line size?
Post by: Darren on February 21, 2014, 06:07:14 PM: Ya if your going to go through the work you may as well put a 3/8" line in and be done with it.

Easiest is to pass a -6 braided line in from front to back.

Don't forget to increase the size of the out fitting on your tank

CB has a nice -6 an adapter.
Title: Re: IDA fuel line size?
Post by: neil68 on August 02, 2014, 02:44:47 PM: Update: So, I went ahead and installed a -6 AN fuel line from the Carter pump (under fuel tank) back to the IDA's. Used the Jaycee top fuel inlets and drilled out the passage to the needle valves to 4.4 mm. Finally got on the Dynojet at Concept 1.

Best results were with F2, 180 main, 210 air, 44 mm Raptor vents: 204.21 WHP and 175.45 ft-lb torque. Both the HP and torque curves were very flat from around 4,000 to 7500 rpms (7500 rev limiter pill was used).

Here's a short iPhone video: View My Video (http://tinypic.com/r/13ymbv9/8)
Title: Re: IDA fuel line size?
Post by: josh on August 03, 2014, 01:45:02 PM: Nice numbers Neil! Did you get a baseline before installing those raptor vents? Kinda interested in picking up a set
Title: Re: IDA fuel line size?
Post by: neil68 on August 03, 2014, 06:10:12 PM: Quote from: josh on August 03, 2014, 01:45:02 PM
Nice numbers Neil! Did you get a baseline before installing those raptor vents? Kinda interested in picking up a set

Unfortunately not. I had limited time that day, so unable to remove the IDA tops and swap vents. I will probably go back on the dynojet in September, and then I'll do the reverse back-to-back tests by installing the stock IDA vents. FWIW, apparently JPM did some testing before the Raptor venturies went into production, and they found a gain of 19 cfm over the stock vents.
Title: Re: IDA fuel line size?
Post by: josh on August 11, 2014, 07:50:51 PM: Nice! Keep me posted Neil
Title: Re: IDA fuel line size?
Post by: Jeremy on August 11, 2014, 10:51:00 PM: 200+hp! Nice.

We going to see you racing Friday night?
Title: Re: IDA fuel line size?
Post by: neil68 on August 12, 2014, 11:01:12 AM: I might not make it to the races this year, but there's still a slim chance. Hope to get to Vancouver in time to see the show on Sunday...