My problem...

[bbaspense]

I run a stock piston in my 400..

The specs:
400 stock pistons
490 something, 292 dur cam
polished crank
ported 452 heads
windage tray
Baffled oil pan
high volume oil pump,
M-1 dual plane intake with heat cross over blocked
recurved distributor
3310 Holley 750
SMR 3000 converter
3.91 gear
Cowl induction with a volocity stack..
3900lbs..with driver

It has run a best of 13.10 @ 104..in the heat, 12.80 @ 107 in the cold spring and fall air..

This is with the power valve blocked in the holley and 78's in the front and a 78 metering plate in the back..

Last year In put a 6 power valve in it, replaced the front jets with 74's and milled off the choke horn..

Now the car won't run quicker then 13.35..in the comparable heat. How can I lose that much horsepower.. I thought all my mods would help flow?

I would like to find a thermoquad to see if my carb mods where the reason for the problem..

[fastmopars .inc]

what is your mph compared to the old timeslip? how many runs have you had to test out the new carb tricks? if it was just a one day or a couple day test and tune, was anyone else running slower?

i would compare the new timeslip with the old and see when and where the power started to drop off, or whether it was just a humidity thing. did you try any other jet sizes than the 74's? maybe its still too fat.

[bbaspense]

I tried it last year at a two day Mopar show.. it is stower all the way down the track..from the 60 ft on..

I'm thinking of putting the carb back the way it was just to check to see if was the jetting or something else..

I did notice that it wasn't as fat at idle (my eyes didn't water) and the throttle responce was better after the changes..

I only had one power valve that I stole out of a 650 double pumper I had.. never checked the actual vaccum.. I just used what I had.. maybe I'm too lean now.. the plugs looked ok..

I'm sure it was a 6..

I would like an adjust a jet so I down have to tear this carb apart everytime..

[Glen440]

If you can make it to TMP I'll let you try the 750 off my 400. I'm working on 2 carbs, one street and one track only. MY street carb is a holley 3310, 2 metering plates, I run 77 front jet with 6.5 power valve and 84 rear jet with no valve. Car went 12.93@107.3 in very bad air. My track carb is a proform bodied 750dp. I only made one pass with it but it went over 108mph.
The dp does not fit my air cleaner so it really is a track only carb. My friend tried my holley 3310 on his 360 and I watched him go 12.30 with it.

I'm trying to have things ready for April 4th. The rotating assembly from my 400 is at the machine shop. I'm waiting for pistons. 3 pistons were siezing on the pins so I'm saying goodbye to 8-1 comp and going to have around 10.2.

Let me know if you can come out to TMP.

[bbaspense]

So you have two metering blocks or plates.. the proform takes a metering block on the secondary side to replace the metering plate..

I'm thinking of going to Mancini's to get a proform main body for my 3310 too.. it's only $99 US.. I was quoted over $250 Can for one here.

I might make that trip to see you.. depending on my work schedule... I'm still using the same 400 I've been using since 1998...