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Discussion Starter #41
Fuel consumption

An unexpected benefit of drilling the extra holes is an improvement in fuel consumption. T drove to Rich Hanning's place this morning, 200 mile round trip, mainly interstate at 75 - 80 mph with a little urban and rural driving on either end plus Rich test drove the car on his favorite back roads. I filled up the tank when I got home and it did 247 miles on 9.9 gallons = 25 mpg. I think that it did 22 - 23 when I did the round trip to Al Mitchell's place for the dyno testing.
 

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An unexpected benefit of drilling the extra holes is an improvement in fuel consumption. T drove to Rich Hanning's place this morning, 200 mile round trip, mainly interstate at 75 - 80 mph with a little urban and rural driving on either end plus Rich test drove the car on his favorite back roads. I filled up the tank when I got home and it did 247 miles on 9.9 gallons = 25 mpg. I think that it did 22 - 23 when I did the round trip to Al Mitchell's place for the dyno testing.
I checked my notes and your 190 hp engine is getting the same highway mileage as the '78 Spider with an unconfirmed 150-160 hp.

I last drove Ed's Spider four years ago, before he installed the 45 DCOEs and the new head and pistons. It was so good I was skeptical when he decided to pursue more power. I am now a believer. From 2800-3000 rpm, the engine pulls harder, longer than the old one and it doesn't seem like it is working very hard in the process. It just goes. And stops. The bigger front brakes are noticeably stronger than the stock brakes on my '78 and I doubt the difference is just pad material.
 

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Discussion Starter #43
Two Spiders

Rich took the picture at his place yesterday. I drove his green 78 and he drove my red 79. His motor has the head and pistons from my previous motor and the same cams but with different carbs and headers. His car is a little smoother below 3000 rpm with it's smaller venturis and it has has good power but doesn't quite pin your ears back the way that the red car does.
 

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Discussion Starter #44
The 25 mpg on the drive to Rich's was not a fluke. I drove to Road Atlanta this weekend to crew for Richard Jemison. It is about 220 miles each way of mainly interstate at 75 - 80 mph. I gassed up on the way home with 259 miles on the trip odometer and it took 10.1 gallons.
Richard took it for a test drive after his races on Saturday and had a lot of fun in it but not as much as finishing second in the Sunday afternoon feature race in his Duetto after swapping the lead a few times.
 

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Richard Jemison
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I had the chance to drive the Spider in the infield roads at Road Atlanta. The roads have been repaved, and simulate mountanious elevation and turns, as well as the skidpad. The car`s drivability and torque/HP is not unsililar to my race cars considering the weight!
This is the best developed Alfa street car I`ve ever driven!
 

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Discussion Starter #46
I did not realize that the car would pull such G force until I sat in the passenger seat with Richard at the wheel. I had to brace myself with my elbow and shoulder against the door on the skid pad.
 

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Discussion Starter #47
While this thread is primarily about my engine build and performance here is a quick description of the handling setup. It has evolved over several years and don't see much more change in the future given the way it rides, handles and brakes. When I offered the test ride to Richard I both wanted him share some satisfaction in the performance since he was a major contributor to it and I also wanted his feedback on the handling as I don't have a good frame of reference beyond some brief rides in competition cars. His feedback was that he would not change anything so here it is.
The wheels are 15" Rotas which are pretty light for 15's.
Tires are Continental Extreme Contact Sport 205/50 ZR15, 32 psi front & 28 psi rear.
Springs are Shankle Super Sport about 600 lb/in front & 150 lb/in rear.
It has RJ dropped spindle uprights from an earlier model with Milano caliper bolt centers.
Front sway bar is stock, Rear sway has been removed.
Front shocks are SPAX adjustables and rears are Koni yellows. The SPAX have a very wide range of adjustment, with 14 clicks and they are set at #11. The Konis are set half way. I started out softer on both pairs and gradually increased them until they controlled the spring return over large fast bumps.
The sway bar links have rubber bushings and all other rubber bushings have been replaced with Performatek poly.
Front toe in is 1/16" and camber is 1 degree negative. I have not measured the castor.
I used a 27mm front sway bar for a few years before returning to stock which has improved the handling, particularly on bumpy roads.
The rear brakes are stock except for a steel braided flex hose. Front calipers are Aluminum Brembos from a Milano which are lighter than the iron Ate's, also with steel braided hoses. Pads are plain organic.
 

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Discussion Starter #48
I spent a lot of time on the carbs over the past few years with many jet changes, enlarging of progression holes and finally adding the 4 holes to each F16 emulsion tube. The low end performance of the 45DCOE152's was pretty bad when I first got them and now it is pretty good but it has a small lean spot. Very often I drive straight through it without noticing it but if I drive around slowly at about 2000 rpm in 4th gear I can hit a bad misfire that forces me to downshift. Today I opened up the gaps of the BPR7EIX plugs to .050" and there is a big improvement. I drove up a grade at about 2000 rpm in 4th and the AFR was in the 18-19 range with no misfiring. I still have to verify that the sparks are still good at 7000 rpm and WOT but I don't expect any issues.
The 123 distributor/MSD Blaster2/ballast resistor can make BIG sparks.
 

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Hey Ed, what do you recommend for a coil when using the XR3000 crane ignition which uses no ballast resistor?
 

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Discussion Starter #50
Is that a CD or an inductive ignition?
If it is CD then go with a CD specific coil with very low resistance and inductance. I think that Summit Racing sell one for a reasonable price.
If it is inductive then it depends upon the minimum resistance that can be used with the Crane unit.
 

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Is that a CD or an inductive ignition?
If it is CD then go with a CD specific coil with very low resistance and inductance. I think that Summit Racing sell one for a reasonable price.
If it is inductive then it depends upon the minimum resistance that can be used with the Crane unit.
Thanks. It is inductive. I'll do more research on the XR3000 requirements.
 

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Discussion Starter #52
I confirmed the plug gap benefit today. I can drive in a higher gear at low rpm than I could before and I see the AFR in the mid to high teens with no hesitation. I went to my "test track" and did a WOT 3rd gear run. My normal protocol is the have the car running steadily at a bit below 3000 rpm in 3rd then floor it and run it up to 7000. It usually has a hesitation when I first step on it and then it runs cleanly. Today I stepped on it at a little over 2000 rpm and it pulled away cleanly with no hesitation. It will be interesting to see if it affects the fuel consumption.
 

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Discussion Starter #53
I'll do more research on the XR3000 requirements.
I looked it up. They recommend their own coils that have a resistance of about 0.4 ohms with no ballast resistor.
Their PS60 is probably the least expensive option. I am sure that an MSD Blaster2 coil would also work fine.
 

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Just got home from O'Reilly's with an MSD 8202 Blaster coil. .7 ohms.
I'll let ya know!!
 

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Did an extensive road test today with the MSD 8202 coil. No resistor, using the Crane XR3000 system the car has always had. NGK Iridium plugs gapped at .030" as always.

Wow. Nice difference over the 42 year old Marelli coil.
 

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Gapped the spark plugs to .040" and did a test drive today. Even better!!
The slight hesitation/bog off idle from a stop is now gone.

I'm gonna get another coil and do this on my Spider.
 

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Discussion Starter #57
Good work.
 
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