Took the Nova to the track on Friday and was not running the times I had hoped. Just put on some Dart Iron Eagle 180 heads w/64cc chambers on the 355. About 10.25:1. With the old stock heads, I ran a 14.5@95 and with the new, I ran a 13.95@97. The engine is a 74 truck motor with flat tops that has been zero decked, balanced and blue-printed and a XE 268 cam with 1.6 rockers. On top, a Holley dual plane intake and a Holley 650dp. Original TH-350 with a 2000 stall and 3.42 posi and 26/8.5/15 slicks. Car weighs about 3500 with driver. Full int and a/c. Nothing was as fast as I had hoped. Here is the time slip for all you to look at.

R/T ..... .309 graemlins/clonk.gif
60' ..... 2.069
330 ..... 5.832
1/8 ..... 8.927
MPH ..... 79.23
1000 ..... 11.638
1/4 ..... 13.950
MPH ..... 97.70

Any input would be great.
Dave

Does seem slow. What are your timing numbers? Whats the jetting on the carb?

A 1/2 second faster with a head swap with same cam seems pretty good to me smile.gif

You should be faster yes. With an out of balance motor, unseated rings, Pro 200cc heads, the 262cam, and a 3750lb car w/ me in it I ran 13.7 with a 2.0 60ft at 101MPH.

Try timing changes. I've seen cars pick up a second because of a bad timing curve.

An extra 500 rpm of stall speed in the convertor would help a bunch. I also run a XE268 with a 2000 stall and while it runs good, that cam really comes alive around 2500 rpms. You'll probably need to make some tuning changes with the better heads too.

I run a 355 with Dart IE 180's, 2000, stall, and 3.42 gears, just like you. I also use a Holley 650 on a Performer RPM. Only difference seems to be I am running the smaller cam, the XE262. I have run a best of 13.54 at 98mph, with a 1.94 60' and an 8.61 1/8 mile at 80mph. My car does weigh 3850 with driver, so you should go about 3 tenths quicker than me once you get it tuned right.

I have two observations...first, obviously, work on the 60' times. Second, I experimented with 1.6 rockers on my XE262 and the combo didn't like it...runs quicker with the 1.5's. Especially with the 2000 stall, which may be a bit tight for the XE268, I think 1.5 rockers will work better for you.

As Mike said..60 ft.
Its all in the 60 ft.

3500 10inch and some 3.73's ;) 4.11's if strip only :D

Is it just me or does that carb (600 cfm) seem a little bit to small for that engine?
Would a 700 or 750 be better?

Thanks for the help. I'll try changing the timing some and jetting it differently. I know all combos are different, but what are some good timing and jet sizes I could try that are working for some of your engines???

Play with the combo. You can't really find out much after just one trip to the track. As has been said a 2000 convertor is awfully tight unless you have a very mild big Big Block.

I run my Holley 650 DP #4777 box-stock...only think I changed was a slightly bigger pump squirter on the primary side. My ignition timing is 12* initial, 36* total.