Stacks Posted November 24, 2013 Share Posted November 24, 2013 Empty Post Link to comment Share on other sites More sharing options...
Oyaji Posted November 24, 2013 Share Posted November 24, 2013 The carbs are what grabbed my attention. . I used to be well-familiar with the IDA and IDF Webers, and still run a pair of 40mm IDFs with 32mm primary venturis on my 2.0 liter 4-cylinder 914 (that's 4 independent barrels, 1 for each of the 4 cylinders). [edit - added pic and vid - found these on Google and added them to illustrate] The really great thing about Webers is that when you have them set up on individual intake runners with 1 barrel per cylinder, they allow independent tuning for each cylinder. If you are patient and have access to a full range of jets, you can tune the engine so that it is pulling to the max. Also, with that level of tunability, you don't have to merely settle for great power at the top end whereas low-end drivability suffers - to the contrary, Webers will tame an engine so that even with wild cams you can get street performance out of it. This is really unusual for carbs, and is part of what gave Webers such a stellar reputation back in the day. . The other part that made Webers shine is how much they flow. Coupled with a good intake manifold, tuned scavenging exhaust headers, and match porting, the damn things will flow enough to unleash the top-end power potential of any engine... which is doubtless why they were original equipment on Porsches, Maseratis, Lamborghinis, and Ferraris (among many others) back in the day. . The downside is that, being carbs, they have no idea about the power demand you are placing on the engine, and they just dump fuel in analog of the flow and vacuum the engine generates regardless of load. This means they will cost you fuel (probably a third more than you would use on the same fuel-injected engine) plus have a tendency to carbon-foul your plugs when the engine isn't running fast enough to keep them hot and clear. You should tune the carbs on the rich side of the stoichiometric ideal for power (~ 12.5-13.0 : 1), but for street if you lean it out a bit to keep the plugs from fouling and your fuel economy somewhat more tolerable (as if! *lol*) then power suffers and you run into ping problems too. Either way, you will never pass an emissions test, and you will have to remove your catalytic converter (and a lot of other stuff). Interestingly, you can get an air/fuel ratio gauge that uses your oxygen sensor... that and multiple sets of spark plugs (plus a sandblaster-type spark plug cleaner) to read between jetting changes will help a lot getting the carbs dialed in. . I am not familiar with the particular setup you have traded for, but just by looking at them I can see you won't be getting the full potential out of them that you would with triple side-draft 2-barrels breathing through a 6-independent-tube intake... [edit - added pic] ... but if you have the right mindset, what you have got should give you many hours of enjoyment both getting and keeping it set up properly (I highly recommend investing in a 4-tube mercury column manometer to assist in synchronizing them). ;) . Also, you get to become a Weber snob, plus you have an excuse to be blipping your throttle when idling (like at traffic signals) to keep your plugs from fouling! :D Link to comment Share on other sites More sharing options...
jimoshel Posted November 24, 2013 Share Posted November 24, 2013 Oh WOW ! ! Loved that shot of the Clifford set up. The first hot rod after market item I bought was a Clifford dual carb set up, very much like the one pictured. only for a '38 Chevy 216, Ran it a whole week before I put a rod thru the pan. Link to comment Share on other sites More sharing options...
yellaheep Posted November 24, 2013 Share Posted November 24, 2013 Must be nice to not have to worry about emissions inspections....... Gonna be cool! Link to comment Share on other sites More sharing options...
Oyaji Posted November 24, 2013 Share Posted November 24, 2013 Oh yeah, forgot to mention - those carbs are gonna be LOUD through the air cleaners when you open 'er up, too! :) Link to comment Share on other sites More sharing options...
Stacks Posted November 25, 2013 Author Share Posted November 25, 2013 Oyaji... I love the sound of the intake with Weber's. I had one on my old Plymouth Arrow pickup and on my Datsun pickup with an L20!! Not sure I will hear much inside the truck cuz of my exhaust, 2 18" glass packs feeding the stacks. And then there's the typical split exhaust manifold cackle of an inline six. LOL I talked to Larry Clifford about the side drafts and he said his and his Dad's experience with them was for all out race use, yes. But for more low end and a much flatter and broader torque curve the dual sync carbs seemed to work better for them. Time will tell. Thank you for the suggestion of getting a manometer! Had pretty much spaced that out. Very good idea!! Jim... I have to agree!! Love the look of them. Like Oyaji mentioned too, the look of triple side drafts is pretty neat too!!!! What's the old saying? "The only difference between men and boys is the price of their toys!" The first engine I ever hopped up was the 273 in my '67 'Cuda. Total build on that complete was $1200 back in 1973. Hate to think what that would cost today!! Will do my best to get lots of pix along the way and get them posted on my build thread. Sure hoping all this will produce the amount of torque Larry Clifford says it will!!! :banana: Later, Larry Link to comment Share on other sites More sharing options...
dasbulliwagen Posted November 25, 2013 Share Posted November 25, 2013 here's a couple pics of similar systems. The first is the VW motor I built for my 1959 VW Bus. I had almost $5000 in the motor and trans alone. This setup has 4-48mm throttle bodies with port injection and it would run like STINK! I should never have sold that thing. The second is a rat rod a saw at a show...most beautiful straight 6 Ive ever seen. Link to comment Share on other sites More sharing options...
Oyaji Posted November 25, 2013 Share Posted November 25, 2013 [edit: just noticed the above post made while I was composing this one and HAD to comment] WOULD YOU JUST LOOK AT THOSE LONG VELOCITY STACKS ON THOSE WEBERS!!! WOOOOOOOOT!!! My 914 cam has 285 degrees duration (Scat C-35), and, though not wild, is much in excess of the stock 234 degrees. It still makes great low-end torque with 4 barrels for 4 cylinders on individual intake runners - so much so that on dirt or gravel even when I release the clutch gently I still get some wheelspin at a 900 RPM idle. Just sayin'... I started out trying to save money on jets by getting just 3 sets total, setting aside the baseline jets untouched, keeping one set as a reserve, and using a jet reamer and micrometer to incrementally increase size until I got my working set dialed in. My local speed shop made me a deal that saved me much headache: they sent me home with their entire stock of jets, and told me to just pay them for the ones I used when I returned the rest. I was shocked to have to step up to from the baseline 1.15mm mainjets to 1.65s before I got it right! Their more-than-kind and trusting offer saved me immense headache and many many hours work hand-reaming, measuring, and polishing the orifices of my own (finish is important because it affects flow). During the years when Webers were popular that offer would have been unheard of, and that level of trust is even more astounding today. (I suppose that has to do more with the current low demand for carbs than with retention of traditional values and personal integrity.) I hope your jetting adventure will be as serendipitous and happy as was mine. I'll suggest that you be very methodical and take copious notes as you go; you'll probably overshoot and undershoot a number of times before you arrive at the ideal setup. Link to comment Share on other sites More sharing options...
87Warrior Posted November 25, 2013 Share Posted November 25, 2013 Nice load of loot! I suspect this build will find its way into your MJ. Very cool! Link to comment Share on other sites More sharing options...
jimoshel Posted November 25, 2013 Share Posted November 25, 2013 :bowdown: Link to comment Share on other sites More sharing options...
Remy B. Posted January 9, 2014 Share Posted January 9, 2014 Hi Stacks, tell us about your setup, did it meet your expectations ( I guess a lot better than the stock, but how much more ), did you had the chance to Dyno, a before and after or a 1/4 mile ET. I'm as well interested in a performance 6 inline and I like the triple weber DCEO carbs, but that is a lot of money and a lot of time setting/tuning those carbs and money to do so to match your internals it will not be a bold on and go situations that is for sure. by the other hand I hear a lot of good comments about the double weber 2 barrel setups, but more related to low and mid range, but it is limited on the high end, and that is what I'm after. the Clifford single 4 barrel manifold gave me the option of eventually Supercharging the engine, but it is way out of my budget now, but at least one have already the manifold and can gradually ride/ enjoy your car on the 4 barrels or a adapter with a good 2 barrel carb and slowly build your project but at the same time take it to the streets. the high performance internals on the 6 inline are pretty much all Custom build that mean a LOT of $$$$ in just single top of the line parts. "505 performance" and "Hesco" have a lot of stuff for this, but one thing I don't like there is not much (almost nothing) about specs descriptions of what you are buying, to me it is more like a blind buy hopping for the best, I know they go to SCAT to build there cranks but I don't like the combination option they have regarding connecting rods, and not much info on the cylinder heads regarding of what I like to know, and just not simple descriptions. Regards Link to comment Share on other sites More sharing options...
Stacks Posted January 9, 2014 Author Share Posted January 9, 2014 Hi Remy B...I'm still in the process of building the engine. The engine U have in my MJ now is not stock so I can't do much of a before and after. It only has about 10,000 on a rebuild but has a CompCams cam in it. The one they list for fuel injection. I have the Clifford dual outlet headers feeding my dual stacks. Seriously... give Larry Clifford a call. He is a great guy to talk to and can give you the ins and outs related the things you mentioned. i.e. dual Webers for low/mid vs top end. The proper cam can take care of that easily. Looks like I may have created a stir on your original post based on the popups I'm getting on replies to that thread. My personal experience with performance engines previously has been with small block Mopars 273/340's. So I am very new to the Jeep 6 performance stuff. As was mentioned... if you are looking to gain say 30HP. You can do that by going to a cat back exhaust with very free flowing muffler and a cold air intake and a K&N filter. I did that on my TJ and it was a noticeable improvement. I'll keep everyone informed on my results. Later, Larry Link to comment Share on other sites More sharing options...
dasbulliwagen Posted January 9, 2014 Share Posted January 9, 2014 :bowdown: Jim stole my picture! I'm so honored! Link to comment Share on other sites More sharing options...
Stacks Posted January 9, 2014 Author Share Posted January 9, 2014 That is a sweet looking set up!!!!! :banana: Link to comment Share on other sites More sharing options...
Oyaji Posted January 9, 2014 Share Posted January 9, 2014 That is a sweet looking set up!!!!! :banana: Considering your screen name, it figures that you would be impressed! I like 'em too... so much that when I get around to it, I'll make some 2-foot velocity stacks to boost mid-range power on my flat-4... Link to comment Share on other sites More sharing options...
Stacks Posted January 9, 2014 Author Share Posted January 9, 2014 How much change can you get out of velocity stack length changes? Similar to tuning extensions on header collectors? Link to comment Share on other sites More sharing options...
Oyaji Posted January 9, 2014 Share Posted January 9, 2014 Yes. Back when most makers were proud to get 75% volumetric efficiency from their offerings, Porsche was able to hit 105% using "pressure wave supercharging" by utilizing tuned intake stacks. :) Link to comment Share on other sites More sharing options...
Stacks Posted January 9, 2014 Author Share Posted January 9, 2014 Tough to argue with those numbers!!! ;0) Link to comment Share on other sites More sharing options...
Oyaji Posted January 9, 2014 Share Posted January 9, 2014 Especially when they came directly from the chief engineer of R&D at Porsche GmbH. :) Link to comment Share on other sites More sharing options...
Stacks Posted January 9, 2014 Author Share Posted January 9, 2014 Definitely!! I had one of our helo pilots when I was in the Navy that had a 911 and he was always muttering about how much it cost him to get the carbs synced in it. This was in 1971-72 and it was around $120-130. Hate to see what it costs today!! Link to comment Share on other sites More sharing options...
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