Drivability/Performance Update

[Elan+2Novice]

Hi All,

Thanks again for all the feedback on my previous thread...Hmm...well I guess I've drawn the conclusion that each Lotus is unique in it's drivability/performance/tempermentalness (is that a word ).

My mechanic is in the process of ordering new main jets for my Dellorto carbs...but has cautioned me that the car will either perform well at low revs < 2500 or between 2500-6000 and not both...this is a bit disappointing....any comments?

After driving it on freeway conditions, and then downshifting to 2nd, then 1st gear, it always stalls out....which supports the theory that the car is performining well in the upper rev ranges...

He also stated that these cars DO NOT do well in stop and go traffic which contradicts another opinion....

So, bottom line.....I don't know... Someone else told me you have to work with the car like a team...maybe I should just treat it like riding a horse...

Cheers,
Linda

[types26/36]

My mechanic is in the process of ordering new main jets for my Dellorto carbs...but has cautioned me that the car will either perform well at low revs < 2500 or between 2500-6000 and not both...this is a bit disappointing....any comments?

Yes,only one.....................find another mechanic

[Elanintheforest]

I totally agree with Brian. When they are set up properly they will tick over all day, won't overheat, won't stall, will be easy to start hot or cold and will rev out without stuttering. The only difference between an Elan and another 4 cylinder car of the same period is that you have to give it a few more revs to get cleanly off the line, as they develop very little power under 1500 rpm.
Talk with Dave Bean in Ca...he knows his stuff!
Mark

[1964 S1]

How many Lotus has your mechanic owned, or worked on? How many Delortto carbureted cars has he owned or worked on? His analysis of performance may be an indication of his performance!

[Elan+2Novice]

Update --- I did call Dave Bean Engineering and spoke with someone that seemed like he had a clue...He agrees with you all and stated the car should perform well in all conditions if tuned correctly. He recommended
1) Check ignition system 2) check for vacuum leaks in the soft mount kit 3) Then look at the carbs.

I also told the Dave Bean guy when I removed the main jets(my current mechanic thinks that is the performance problem) that the gaskets were missing. He said "not good". I told him my mechanic said it wasn't a "big deal" that the gaskets were missing, which surprised me, but what do I know?....bottom line....yes it is time to find a new mechanic who has worked on Dellorto carbs....

Thanks again for your comments,
Linda (69 Lotus Elan+2)

[types26/36]

I also told the Dave Bean guy when I removed the main jets(my current mechanic thinks that is the performance problem) that the gaskets were missing. He said "not good". I told him my mechanic said it wasn't a "big deal" that the gaskets were missing,

Linda,
I really dont know which gaskets are been refered to, there are no gaskets under the main jets if thats what is being implied, any other gaskets in/around the carbs are there for a reason, usually to seal the item and are therefore nessesary.
The main jets will effect performance but mainly at the high end of the rev range, jets dont really wear out and unless some one has changed them for much smaller ones the standard jets will be fine for a most applications.
If you have the main jets out and do not have any specs post the size so we can tell if it is within reason.
As has been mentioned, get some one with common sense to check the car from basics, point gap, timing, compression, connections, air leaks, plugs, air filter etc. before going to carbs and extream measures and let your "mechanic" (and I use the term loosely) stick to his model T Fords or hotrods.

[denicholls2]

Unlike many carburetors, the idle and main circuits of Weber and Dellorto carburetors are remarkably independent. Tuning issues generally arise in making a smooth transition between the two circuits, which requires skill and patience.

Given that the idle jets are in control up to about 3,000 RPM, your mechanic's strategy of monkeying with the mains to correct low-speed performance is a clear indication that he has no clue. Ditch him before he ruins your car and your bank account.

-- Doug Nicholls, 54/1822 Ma~

[Elan+2Novice]

Just for clarity's sake regarding the missing gaskets....(per workshop manual) the gasket between the emulsion tube and jet main air corrector were missing...The Dave Bean guy said the Dell carbs are very sensitive and the missing gaskets may...well probably would have effect on performance....it is just common sense....all the pieces should be there! (even I know that)....

[dlbarnes1]

Since you are in Truckee at elevation 5000-6000 feet, keep in mind the effect of that elevation on carb setup and performance. If you talk to Ken (or Dave) at Dave Bean, you should get some guidance in that regard.

Dave - 72 Sprint DHC