Jump to content
Sign in to follow this  
Guest Anonymous

Just got back from the dyno

5 posts / 284 viewsLast Reply

Recommended Posts

Guest Anonymous

I thought you guys might be interested.

Best run was 140.1 hp at 6,200 RPM. I didn't want to turn any higher rev's as the engine only has 8 hours of break in on it so far. It was still climbing at 6,200 and so maybe had 4 or so hp more in it had I reved higher. Max torque of 124.2 occurred at 5,200 RPM. Did this north of Atlanta at around 1,000 feet elevation and close to 90 degree day. The dyno operator said we should get a little better readings after the engine breaks in more. He also said that they have measured drive line losses at between 15% to 20%. Assuming 17.5% for our ride, would give us 170 hp at the flywheel, which seems pretty good to me.

If my math is right, this engine is displacing 2.13 liters or 129.98 cubic inches. We have 90MM pistons and standard stroke. Our power would be equivalent to a 350 Ford or Chevy putting out 458 hp. So the old 4 banger is humping it.

This engine has 11 to 1 Venolia's, Schrick 304, extra big Stahl header, Weber 45's. It has an E21 head that's been massaged and port matched.

Our best run was with 36MM venturi's, 145 mains, 60F8 idles, and 200 air correctors. Our air/fuel ratio was all over the place, particularly in the progression phase. It was lean at first, got about right at 2500, then climbed to lean again at 3300, then too rich by 4000 and then started to improve to pretty decent, so the main and air correctors are keepers. We need a little richer idles and may need to mess...God help us...with the emulsion tubes. THe part everyone says don't mess with. These Italians were nuts. I like Webers but they are a total PITA. Stick with a 38/38 if at all possible. Imagine 6 of these damn things on a Ferrari. 2 is more than I can deal with already. Maybe ignition advance curve may have something to do here with our wacky progression, but we are most interested in how it runs 3500 and up, and we are at max advance here already.

We also tried to run the car with 38MM venturis and it was a disaster, performance was abismal, and all we did was increase the opening area by 11%??!! That part totally floored me. We tried bigger jets, and to no availe. Our piston / cam set up may not have enough suck to power these, or more carb bits need changing than I had or know how to do.

Best power was made with total advance at 37 degrees, so that's where we are leaving it. Power dropped at 39 degrees and at 35 degrees, but torque was a whisker higher at 35 and came a little sooner as I remember. Seat of the pants dyno does a good enough job here. The timing where it idled smoothest also lead to best top end.

Share this post


Link to post
Share on other sites
Guest Anonymous

(nt)

Share this post


Link to post
Share on other sites
Guest Anonymous

(nt)

Share this post


Link to post
Share on other sites
Guest Anonymous

(nt)

Share this post


Link to post
Share on other sites
Guest Anonymous

(nt)

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.