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914World.com _ 914World Garage _ fuel

Posted by: markasap Mar 24 2005, 11:36 PM

what is the best setup for a stock 914 2.0L motor
1 fuel injection
2 single 2 barrel webber
3 duel 2 barrel webber
what are the pros and cons
the best overall proformance
Thanks
Mark

Posted by: chilli Mar 24 2005, 11:39 PM

IMHO the stock fuel injection is far superior than carbs, whole bunch less hassle. Of course this is based on the fact the fuel injection has been maintained and works like it is was desiged, and has not been messed with buy someone how does not know to tweek it.

mike

Posted by: Jake Raby Mar 24 2005, 11:42 PM

Not a fan of stock injection here... But I like to cut and modify everything I see..

Dual carbs or Aftermarket injection..

Carbs are not a hassle if you understand tham and can tune them and primarily set them up right initially... Thats the main reason why people don't have good luck with carbs because they are not set up right..

Posted by: ArtechnikA Mar 25 2005, 07:18 AM

it's "dual"
it's "Weber"

it's a very complicated subject that can't be covered in one thread on ANY forum.
each has its place, its pro's and con's, must be properly matched to the engine, cost is always a factor, and legality (emissions or competition class rules) sometimes is.

there are dozens of excellent books and articles that cover all this stuff in the depth it requires.

oh - welcome to the club !

Posted by: Bleyseng Mar 25 2005, 08:45 AM

Stock FI in good condition is much nicer than dual carbs any day. Car runs better, starts instantly, good cold running etc....
Carbs are for modified engines.....

Aftermarket EFI is good too but costly.

Geoff

Posted by: Joe Sharp Mar 25 2005, 08:52 AM

I think this is a very personal thing. In the last year I have spent over $1,000.00 on parts and almost that much on tools for the D-Jet. I have also scraped an L-Jet system for dull singel 40 Solex sorta like the factory. If you understand carbs stick with them, if you like the D-Jet or L-Jet and you understand them, Its Your Thing, Do What You Wanna Do.
Joe

Posted by: sean_v8_914 Mar 25 2005, 09:07 AM

stock cam, stock FI
aftermarket cam, go carbs
other posts have valid points based on there experiences. I never go with what I know, allways taking the unknown path. Now I understand D-Jet and L-Jet

Posted by: Dave_Darling Mar 25 2005, 06:28 PM

The single-carb setups work well as paperweights... Not as any way to get air and fuel into a 914 engine.

--DD

Posted by: Joe Sharp Mar 25 2005, 07:33 PM

Dave: VW did things for a reason. I would be happy to have you drive the Solex Twin singel carbed car at the Wild West Classic. You may change your mind about paper weights.
Joe

Posted by: Mueller Mar 25 2005, 07:36 PM

QUOTE (Joe Sharp @ Mar 25 2005, 06:33 PM)
Dave: VW did things for a reason. I would be happy to have you drive the Solex Twin singel carbed car at the Wild West Classic. You may change your mind about paper weights.
Joe

I'm pretty sure Dave was talking about using a single carb......you have 2 carbs mounted in the proper location.

Posted by: SirAndy Mar 25 2005, 07:44 PM

QUOTE (Bleyseng @ Mar 25 2005, 06:45 AM)
Stock FI in good condition is much nicer than dual carbs any day. Car runs better, starts instantly, good cold running etc....
Carbs are for modified engines.....

stock engine, go with the stock FI ...

carbs will *NOT* improve performance unless you brake the case open and add a more agressive cam-shaft.
the stock FI will run better, start better and produce more HP on a stock motor.

plus, you don't have to re-jet your FI if you drive up to the mountains ...
Andy

Posted by: Eddie914 Mar 25 2005, 07:48 PM

I Webers on my track car are great (40IDA3C on a 2.7)!

The fuel injection on my daily is great (Motronic on a BMW M5)!

... everything has it's time and place.

If I could just get the 260hp of the daily driver into the 914/6 without breaking the bank (or the weight savings ... the M5 motor weighs about 550lb!)

Eddie

Posted by: D-Jet Mar 25 2005, 07:53 PM

This is an interesting thread. I have a similar question. How flexible is D-Jet. I know not very, but how bad. I'm looking to replace the intake, headers and exhust on my stock '75 2.0. Will I see any performance gains without messing with the D-Jet? Any idea how much?

--G

Posted by: SirAndy Mar 25 2005, 08:01 PM

QUOTE (D-Jet @ Mar 25 2005, 05:53 PM)
Will I see any performance gains without messing with the D-Jet?

you'll need to re-calibrate the MPS, which can be done ...
in fact, i just gave Mueller the recalibrated MPS to go with my old 1.8L D-Jet ...

i know of several 2056cc 914s with headers/SSIs/sport mufflers and stock D-Jet.
they run fine ...

carbs or aftermarket FI are only needed if you go with a non-stock Cam ...

oh, and another thing no one has mentioned so far, the stock FI will give you MUCH better gas mileage!
Andy

Posted by: Mueller Mar 25 2005, 08:15 PM

QUOTE
. I'm looking to replace the intake, headers and exhust on my stock '75 2.0

be warned, it's not a Honda, or even a Ford Focus for that matter......doing all that is not going to get you as much HP as you think it will....

the best bang for the buck will be a nice header and street muffler like the European Racing setup

QUOTE
I'm looking to replace the intake,

Do you know something we don't?? Where are you going to find this "magical" intake to be used with the D-Jet??

Posted by: D-Jet Mar 25 2005, 08:28 PM

AA?

http://www.autoatlanta.net/record_detail.lasso?-database=AAdatabase&-UserName='public'&-Password='public'&-layout=Items&-KeyField=__Record_ID__&PartNumber=RMB34295&-Session=ShopCart:45E6D29A07ef933D75WRT2A53313&-Search

Perhaps intake isn't the correct term. Air filter?

--G

Posted by: Joe Sharp Mar 25 2005, 09:09 PM

D-Jet: I have the engine you are asking about. 2056 with 9.0 CR, Ported, Web 107i cam, balanced and a lightened flywheel. I'm in the middle of adjusting the MPS. Unless you are an experinced engine builder I would Not recomend messing around with D-Jet or the MPS.
Someone on this board did a test on the D-Jet air box and engine bay temps. I think it was Demick. Not sure. I think the title was " 4HP for $4" Much cheaper and real results.
Joe

Attached image(s)

Posted by: D-Jet Mar 25 2005, 09:16 PM

QUOTE (Joe Sharp @ Mar 25 2005, 07:09 PM)
D-Jet: I have the engine you are asking about. 2056 with 9.0 CR, Ported, Web 107i cam, balanced and a lightened flywheel. I'm in the middle of adjusting the MPS. Unless you are an experinced engine builder I would Not recomend messing around with D-Jet or the MPS.
Joe

Nice! That's exactly what I have in mind. I know where the engine is, does that count as experenced? I'm guessing not. What kind of hp/tq (approx) do you think you'll be getting?

Posted by: Bleyseng Mar 25 2005, 10:03 PM

I was getting 95rwhp or about 110-115 at the flywheel with a 2056cc motor. 42x38 valves,ported heads, bursch muffler and I tuned the Djet.

Makes for a quicker 914...

Geoff

Posted by: Joe Sharp Mar 25 2005, 11:54 PM

Geoff's is complete and its been on a dyno. I would only be hopeful to get that good of results.
Joe

Posted by: D-Jet Mar 26 2005, 12:38 AM

110-115? Nice. That sounds awesome. Not that it's relevant, but my name is Geoff also. “G”s of the world UNITE!

--G

Posted by: Mueller Mar 26 2005, 12:44 AM

Hey Geoff...(the new one, )

thought about putting an SVT focus motor into a 914??

Cool engines, tons of potential with them

Posted by: rhodyguy Mar 26 2005, 01:15 AM

geoff's used to be complete. now it's completely apart for a displacement increase.

k

Posted by: D-Jet Mar 26 2005, 04:08 AM

Hack up my Focus? For the moment I'm just looking for a little extra kick. Down the road I'll be looking for a lot more power. A big boxer-4 sounds so right. Though if I (like most) can find a nice boxer-6. . .

--G

Posted by: davep Mar 26 2005, 06:45 AM

Jake is the experienced type 4 engine builder and can help you out with anything you can afford up to a 3L type 4. Up to a 2056 is manageable with stock FI. Larger, then aftermarket FI seems to be the way to go. FI can easily compensate for very low temperatures and large altitude changes.

Posted by: Joe Sharp Mar 26 2005, 08:35 AM

G--- Come on down and look at my D-Jet project, D-Jet. Its taken me a little over a year and I'm getting excellent results. All or the Gurus are up north, But they watch what we are doing, and are not affraid to correct us.
Joe

Posted by: D-Jet Mar 26 2005, 11:50 AM

Cool, thanks for the offer.

On average, how much do aftermarket FI systems cost?

--G

Posted by: ArtechnikA Mar 26 2005, 11:59 AM

an average may not be as helpful as you'd like...

the MegaSquirt is in the $350 range if you're the handy type and can handle light fabrication and assembling a circuit board. assembled units are available if you don't mind paying for someone else's time. fancy throttle bodies add to the cost and performqance potential but aren't needed for a stock-ish engine.

at the upper bound are systems like the Haltech and Motec that can hit $10k with all the bells and whistles - that includes stuff like data acquisition, fuel and spark management, forced induction...

so it's more like tiers. entry-level stuff (that is far more capable than the best the factories were able to do 40 years ago...) under $1000. more sophisticated systems like the Kit Carlson, ready to go for under $2000. and the pro-grade racing-ready stuff for under $10,000.

Posted by: Dave_Darling Mar 27 2005, 08:28 PM

QUOTE (Joe Sharp @ Mar 25 2005, 05:33 PM)
Dave: VW did things for a reason. I would be happy to have you drive the Solex Twin singel carbed car at the Wild West Classic. You may change your mind about paper weights.
Joe

A few points. "Twin single carbs" are not a single-carb setup, they are a dual-carb setup. Two carbs, in this case, really are better than one!

VW put single carbs on a whole ton of Bugs. But those are Type I motors, and they have heat risers to warm up the carb so the thing doesn't run like crap. No heat risers on the 914, so a single center-mounted carb will almost always run like crap.

Finally, it is rather unlikely that I will be able to make it to the WCC. Lack of financing, if I don't get a new job soon, or lack of time, if I do. And that's assuming I can even fast-talk Howard into taking my entry way late...

My comment applied almost exclusively to the DFAV 32/36 (I think the designation is) "Pinto Weber Progressive" carb, which has two barrels but is one carb that sits over the middle of the engine. Might work on a Bug, but as far as your 914 goes, it's a paperweight.

--DD