| Author | Message | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 496 Registered: 2-2003 |
Philip I absolutely agree. Would go back to the 34s for driveability over a few ponies up top. Would look at 155 - 160 a/c's as a wag based on the prior experience. Hey - tell me about your accel pump jets - size, response, etc? I think my 60s may be a bit rich. See new part 4 post. best rt | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 445 Registered: 7-2002 |
Russ I ran the car with the 36mm venturis/150 mains/65 idles/185 AC late yesterday. Idled ok, not great but Ok. Mid range OK (I think the main is about right). Top end weak - needs a bigger AC. However, biggest issue is the lumpy running below about 4000. I am going to go back to the 34s as a compromise I can live with. I don't doubt that the 36s will deliver quite a bit more power at the top end when properly jetted, however it is a bit of a pig around town. Of note, two other sources using bigger carbs (42s - UK; McCormick, 44s) both ran 34 mm chokes. | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 440 Registered: 7-2002 |
I now know the meaning of "standout" through the carbs. Flames lit up the entire engine bay at about 3500 - 4000 rpm with light throttle! I put in the 65 idles. Ran it. Let it idle. Backed the idle mixture screws out progressively a total of one complete turn. Idles pretty well. Should get the bigger mains tomorrow. To your point, Russ, amazing what 2mm does on the venturis! Progress but not perfect yet. More to come. | ||
| Edward G. Salla (350hpmondial)
Member Username: 350hpmondial Post Number: 373 Registered: 2-2002 |
Russ, Damn hurrrrrrricain...! Best thread ever. She's a beast, , , , , , , and I want her. | ||
| Mark Eberhardt (Me_k)
Member Username: Me_k Post Number: 705 Registered: 5-2002 |
Great!!! | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 436 Registered: 7-2002 |
Congrats Russ. I know it has been a birthing process. Look forward to more when you have the digital camera going. | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 489 Registered: 2-2003 |
IT'S ALIVE! Was not there, but after fabricating and elegantly simple linkage, I'm told they started it up and drove it around the lot yesterday. Started absolutely instantly. While not descibed as offensively loud (carbs+tubi+Stebro resonator), the mech said the sound of the engine with the new carb induction noise is fantastic ('snarley') and the whole shop is enthusiastic. Will need to sl. trim the underside of the decklid to clear the air cleaner, but everything will line up great. Will be synching the carbs and setting the mixtures after the hurricane. Pictures next week. Damn hurricane. I can't wait to get up there. Best regards, and thanks to all who have advised and supported along the way Russ | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 487 Registered: 2-2003 |
Hello from the Hurricane Isabella target area! Philip, I am extremely interested in how the idle jets work out. I think you need to turn up the heat across the board, as I will bet your cams and requirements are not too different from the Austrailian Cam'd 308 below, which ran 152m/155ac/62id - and that was with 34mm venturis! I'm a thinkin' that you are looking at 260-270hp+ at the rear wheels and over 300hp at the flywheel as well - that's just how much flow it takes. | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 435 Registered: 7-2002 |
Russ I talked to Pierce yesterday and ran through my symptons. Here's where we came out: - Idle. Increase jet size. No 62s in stock, have 65s which I'll try. - Mains. Will put in 150s. - Accel pump. Going to leave stock at 45 for the moment - the LeMans car was the same too (but with richer mains) - AC. No insight yet. Will leave at 185 and do a plug cut at the track to test. I hope to have it back together this weekend. Amazing noise (quality, amount) from the intake without the airbox (or deck lid) on the car. More later. | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 429 Registered: 7-2002 |
Russ Good thoughts. I'll give it a better test and report back. Philip | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 483 Registered: 2-2003 |
Philip Terrific report. Would absolutely look at richening the mixture across the band. Did you find you may need larger pump jets when the throttle was opened rapidly? It's amazing what a 2mm change, less than 5% of the diameter, can make. | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 428 Registered: 7-2002 |
Russ Well, the rain eased a bit and I took advantage of a window for a short test run. It feels like it is lean across the range, but particularly at idle and also in the 3000 - 5000 range (spluttering or standout through the carbs). I am waiting on some new fuel line hardware and will try the 150 mains. Also going to look at richening up the idle a bit. I haven't had the chance to wind it out on a long stretch, but the initial impression is a loss below around 2500 or 2750 from the venturis, as you'd expect. | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 481 Registered: 2-2003 |
Philip Have been taught the A/C primarily affects richness in the mid to upper end. Based on that austrailian cam'd 308, would look at a 150 main AND a 150 - 155 A/C to beef up the mid - high range. I've gone ahead and will have a set of 190 and 175 A/C jets available next week when we start to bracket requirements. I'm learning a lot from all this. | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 426 Registered: 7-2002 |
Russ I have the 36s in, trumpets (velocity stacks) temporarily mounted and after finding some temporary hardware to seal the fuel line bayonets, started her up without the airbox et al yesterday. Waiting for the roads to dry out to try it properly. Sound is incredible. From my experience at Gingerman on Monday last week, I think it is going a bit lean in the mid range, which the 36s will likely exaggerate, so I am going to try a larger main (150s). Keep you posted | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 471 Registered: 2-2003 |
Philip I'm sure she will idle as the venturis are upstream on the throttle butterflies - and I am sure it will run. In my mis-spent youth, I converted a FI Alfa 1750 Spider to twin sidedraft 40 DCOE Webers from a 1600 coupe found in a parts yard. Once, I took the venturis OUT and drove it around. What a howl, and sluggish response, but it went!!! Let us know. If you don't use the 36s pemanantly, let me know and perhaps we'll work something out as you have my curiosity up. | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 424 Registered: 7-2002 |
Russ I fitted the 36mm venturis tonight. Waiting on new fuel line bayonet washers and will then temp fit the venturis and start her up to make sure she'll idle before putting the airbox and hood back on. While I had the tops off, I checked the float heights (48mm) - spot on. Still wondering about the 44 DCNFs. | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 468 Registered: 2-2003 |
Barry Thanks for the words! Best I can tell, it will be the world's first (and only) carb'd Mondial...or Ferrari 3.2 engine that I can find. I waiting for that call from Cavallino or Forza for the magazine cover shot....NOT  | ||
| Barry Wolinsky (308gtb)
Member Username: 308gtb Post Number: 673 Registered: 2-2002 |
Russ, It looks REALLY good so far! I like what you're doing to your Mondial. Barry | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 466 Registered: 2-2003 |
UPDATE: Good news - just realized that the ABS brakes DO NOT need a vacuum take off. Wow. So, will just put one small vacuum hose leading to the A/C control system. Carb re-jetting: Well, after looking at a few more examples of jetting, am considering changing the a/c jet to 175 from 190 to keep the richness in at high flows (34mm venturi, 150 mains). Any advice welcome. Will be utilizing the existing O2 sensor to a temporary Hall meter to watch mixture. Will be venting crankcase through to aircleaner using original 308 stuff - anyone know how neccesary the vacuum line id to the air/oil separator? The gas tank vent will go to the airbox. Still working linkage to get it just right with Pierce Manifolds. Suggestions/Advice welcome. Ben Millermon is finishing the distributor and block off plate this weekend. Will remove the Marelli coils and fit the new distributor to the front (bow) bank. The MSD unit will go in the trunk where the ECU used to be. Will power everything from the original harness, and try to use the Marelli ignition ECU to run the tach. If not, Ben has a tach adapter.  Philip Sorry, not near the car or my books and the online parts catalog does not have the washer size either. Pierce Manifolds # is 800-874-3728. Next week is looking like Almost Final Assembly Week and start it party. Wish us luck. best rt | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 415 Registered: 7-2002 |
Russ I am installing the 36mm venturis. Do you know the size of the copper/fiber washers on the fuel bayonets? Mine are at home and I need some more. Philip | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 464 Registered: 2-2003 |
Barry - thanks! Interesting the airbox I got did not have the rivet holes for one. I guess that is because it has a foam noise silencer around the inlet opening - new to me. You can see in the picture how it is built up. Thanks again, best rt | ||
| Barry Wolinsky (308gtb)
Member Username: 308gtb Post Number: 668 Registered: 2-2002 |
Russ, the Firing Order Plate (Ordine D'Accensione) Peter mentioned looks like this:  as installed on an early carburetted 308:  Barry | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 462 Registered: 2-2003 |
Jeff Howe is great. Highly recommended. Check out the Superformance tech chat - a guy modded his 308 with 42dcnfs, 302 cams and pistons and got 270 RWHP!!! That's like 320 or something at the flywheel. Quote from the thread: the carbs are setup as follows, chokes=34mm (42 dcnf ) idle jets=62 main jets=152 air corrector jets=155 aux vent and accelerator pump, standard the the 42 dcnf. this setup was established using a rolling road/dyno. the car drives really nice at town speeds. i have have the odd bit of tempermental starting, but this only uccurs when she hasn't been started for more than about a week. the spark plugs are of a cold grade and the engine needs them to get up to operating tempreture before it's fully happy, but when all the fluids and plugs are up to tempreture... the performance and that sound! Unquote. http://www.superformance.co.uk/cgi-bin/yabb/YaBB.cgi?board=tech;action=display;num=1045485250;start=0 Pretty impressive. Very inspiring. I'm hoping for 260 - 265 RWHP or so. Hopefully mine will be running by next week - will report back. Again - thanks to Jeff Howe rt | ||
| Jeff Howe (Ferrari_uk)
Member Username: Ferrari_uk Post Number: 538 Registered: 12-2002 |
Hi all. We have now shipped Russ his venturis !! See our new carb thread - we have loads of internal Weber bits here ! Cheers. | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 459 Registered: 2-2003 |
Update: Fuel system is complete and wired - will be running a return hose. Using an inline filter and Holley pressure regulator with the Facet pump. And for those of you wondering how I was going to connect the Air Cleaner box to the shortened Mondial duct of larger size, I have found a section of heavy duty tire inner tube that fits snugly around each end that will also have a clamp to hold. Thought of that myself. Working linkage issue. Still desperately seeking 34mm venturis - Jeff Howe where are you? You have mail. Also a word on Carobu Engineering (from Forza 308 mods): they have been great to bounce ideas off of and are following this conversion as well as theirs - great folks to work with. Any suggestions on what all of this working well removed FI manifolds and kit is worth? thanks to all! best rt | ||
| '75 308 GT4 (Peter)
Advanced Member Username: Peter Post Number: 3072 Registered: 12-2000 |
Looks great Russ. Now to finish it off, get proper cover nuts (gold-cad plated knurled "buttons". I got mine from Superformance, but I bet FofUK has 'em too) and add a firing-order aluminum plate ( Berlinetta Motorcars has them at a reasonable price. Maybe FofUK as well). | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 453 Registered: 2-2003 |
All Thanks - I'm pretty well convinced that the return line is the way to go now. On another note I decided to follow Peter's advice and do the airbox myself. Took a Scotch bright and knocked off the surface rust from a few small places and after a thorough (and supervised) detergent wash and rinse by my 10 yo daughter volunteer, followed by a rinse and dry with rubbing alcohol, three coats of Plati-kote high temp black crinkle coat ( "for cam covers and air boxes" ) was applied. One can was all that was needed. I'm pretty happy with the result. Still desperately seeking a set of 34 or 36mm Venturis if anyone knows where to go. best Russ   | ||
| PSk (Psk)
Member Username: Psk Post Number: 923 Registered: 11-2002 |
One of the advantages of the return line is it takes the pressure off the float needles in the carbs, ie. if your pump is supplying way too much fuel the needle valves have to seat hard ... I would stick with the return line myself Pete | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 409 Registered: 7-2002 |
Russ Pierce indicated to me they were expecting a shipment [of 36s] in from the UK on 9/12. I also talked to Webcon in the UK and they don't have any right now so my guess is someone has got to make them up. Jeff Howe at Ferrari UK has come to my rescue with a set (thanks Jeff). | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 450 Registered: 2-2003 |
Andy - I'm interested in the 34mm DCNF chokes. You've got mail. best Russ | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 449 Registered: 2-2003 |
Philip - About $11/choke new and $10 each to mil. Will know more Thursday. Andy - Thanks for the offer! Not sure what they are worth either, but applying the older 50% used part rule that would be about $5-$6 per choke, or $40 - $48 for the required set of eight. Does that sound fair? - I'm just guessing here. Do you have all eight? A complete set is the key. Again - many thanks for offering. best rt | ||
| Andrew A. Illes (Andyilles)
Junior Member Username: Andyilles Post Number: 190 Registered: 10-2002 |
Pretty sure I have a set of 34mm chokes for 40DCNFs.. they'd be out in the barn. Anybody want me to try to find them? As usual, I have no idea what they're worth/what to ask. Regards, Andy | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 407 Registered: 7-2002 |
It would seem to be a simple enough job. Are they saying the cost of the chokes is $10 or a choke ($11 - 12) plus $10 to machine each? | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 447 Registered: 2-2003 |
Philip - Breaking news - Pierce manifolds just called and said that the chokes would not be in until mid October, if then. They can machine out the commonly available 32mm choke to 34 or 36. He said that they have done this before. $10. It sounds easy enough - anybody with experience or advice? | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 442 Registered: 2-2003 |
Philip Pierce is also out of 34mm venturis, so we are both on hold. Talked to them on the phone and they did concur that 34mm/150/190/.6/.6 was about right. Will be very interested in transition. Peter - Will try the high temp spray. Alan - will look at finding an orificed fuel fitting for a return line thanks all! rt | ||
| '75 308 GT4 (Peter)
Advanced Member Username: Peter Post Number: 3055 Registered: 12-2000 |
Russ: "Will be repainting vs. powder coating the airbox crinkle black this week. Any pros/cons on straight high temp paint vs powder for the airbox? (Cam covers are powder)". My airbox had an intact wrinkle surface, but was matte in finish. A few light coats of a high-temp, glossy black paint over-top the old wrinkle surface made it look new again. Very quick and easy. Clean the box with soapy water and rinse thoroughly before to get rid of any grime that may be on there. Powder-coating is unnecessary for an air-box (not subjected to vast amounts of heat, and rough service/wear-and-tear. I'd even say the P-C was not needed for the cam covers too...). | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 404 Registered: 7-2002 |
Russ Quick note. Pierce is out of the 36mm venturis. Will have to wait on results. All looks great Philip | ||
| Alan Ing (Alan)
New member Username: Alan Post Number: 19 Registered: 2-2002 |
Hi Russ, I'm no expert, but I thought I read somewhere that a fuel return line helps to prevent vapor lock. My 1977 308 has so many hose fittings on the top of the tanks that I would think that a QV fuel tank would have an extra fitting or two that you could use for the return line. Especially since it appears that you don't need your smog equipment. | ||
| Russ Turner (Snj5)
Member Username: Snj5 Post Number: 438 Registered: 2-2003 |
This is beginning to look really good. It truthfully does look better in person. Especially to me. News/issues: Although GT Auto Parts told me they would respec the carbs, they did not (Grrr), so will be calling Pierce Manifolds tomorrow for the correct initial settings (34mm/150/190/.6/.6). With removal of the inside metal piece, it looks like the air cleaner will just fit under the stock bonnet - way cool. Note especially that these manifolds position the carbs where a stock airbox will work. Frank Capo of Modena Engineering who cast the manifolds is a sheer artistic genius - some one in Oz tell him please. Will vacuum tap one runner for the brake booster line (like 308GT4) and one runner for the a/c controls. Linkage is the main thing that is yet to be worked out, but we have ideas - if you have some pass them on!! Will hook up the crankcase breather to the airbox sans the small vacuum hose as on a 308 will be able to run fresh air flex hose from scoop to airbox after shotening channel. News to me: the airbox looks to actually has a little silencer built in the inlet nose. It's still gonna' howl! Will opt to go with one way fuel to carbs without a return unless I'm missing a reason why we should. Advice welcome. Will be repainting vs. powder coating the airbox crinkle black this week. Any pros/cons on straight high temp paint vs powder for the airbox? (Cam covers are powder) Grand Touring has a dyno, so will eventually have some numbers, but the way it looks and like it's going to sound, I mean, woo-hoo! Any advice appreciated - hope to have it running soon. Will try to figure out how to record. If you want to see/hear it and you're near DC, let me know and we'll arrange a party. Of course with the qv, longer ported/polished runners, webers, tubi and stebro resonator, you will be able to hear it in DC. This could be pretty amazing. Looking at it you just know that it will breath and respond light years ahead of the Kjet. Thanks to the FCHAT and Ferraritech folks for all of your help so far!! best Russ     |