360 power

[charlesvolare]

I built a 360 for my Volare sedan. It's been a great project and I've finally gotten it together and running good enough to take it to the drag strip for test and tune. It ran 14.2's in the quarter, 2.089 in the 60', but when I plug that into the online power calculators, everything puts out my car is making ~240 hp. I was hoping I would be making more than that... During the passes, the car would pop on the top end, I'd have to shift a little early to stay in the power. And it's a slug off the line, but I'm thinking it just needs a higher stall converter and possibly a locker after that. I'm thinking the top end part is fuel, it only does it under load. In neutral it'll rev past 6000 rpm no problem. Does anyone having any suggestions or comments on what I can do? I'll probably re-check pushrod length soon, within the next week or so.

Specs:
Weight, guessing around 3500 lbs.
Bored .060" over, eagle rods, KB flat top pistons, late model magnum heads, comp cams XE268H cam (with magnum 1.6 ratio rockers-268/280 advertised duration, .509/.512 lift, 110 degree lobe), hughs spings, dual plane air-gap, holley 600cfm carb, stock mopar ignition, distributor has a limiting plate in it so it's at 22 degrees initial and 36 total. Beefed up non-lockup 904 trans with stock stall converter and stock valve body. 8.25 rearend with 3.55 gears. Electric fuel pump- holley mighty.

 

[Oldiron440]

How do the plugs look after a pass?

 

[charlesvolare]

Haven't checked from just a drag pass, I'll get a set next time I go. It's a daily driver and for puttering around town and some highway use the plugs look nearly perfect. I'd still think it should make at the least 50 more hp though

 

[Oldiron440]

Is it a vacuum secondary carb?

 

[charlesvolare]

Is it a vacuum secondary carb?

Yes

 

[brotherGood]

I'm gonna watch this one..that combo sounds rather close to what direction I'm headed in mine. I would figure on lack of fuel myself, but I don't know enough about it to feel solid in that assertion.

 

[Oldiron440]

The vacuum secondary carb is setup with the stiffest spring from Holley, I would get a spring kit and a jet kit so you can tune your carb. The secondary have a metering plate instead of jets so I have found that the primary side needs to be just a little richer for WOT and I have tried every spring in the kit and used the fastest opening spring, I believe it's white.
I used this carb on a 289 Ford with much success 14.0s@99mph. Your 360 would benefit from a 750 do and a converter that has a 2400 to 2800 stall. I'm positive that's killing you 60 ft times.

 

[charlesvolare]

The vacuum secondary carb is setup with the stiffest spring from Holley, I would get a spring kit and a jet kit so you can tune your carb. The secondary have a metering plate instead of jets so I have found that the primary side needs to be just a little richer for WOT and I have tried every spring in the kit and used the fastest opening spring, I believe it's white.
I used this carb on a 289 Ford with much success 14.0s@99mph. Your 360 would benefit from a 750 do and a converter that has a 2400 to 2800 stall. I'm positive that's killing you 60 ft times.

I have a jet kit already, and I believe I have a spring kit too, I just have to find where I put it. I bought it and didn't feel like taking the carb off and apart at the time.

 

[Oldiron440]

I believe that's where your power is. I live on the edge of town and tweaked on my carb for a couple of weeks until it worked like I wanted, a lot of pass's on the black top.

 

[volare 77]

Do you have a fuel pressure gauge on the car?

 

[charlesvolare]

Do you have a fuel pressure gauge on the car?

Yes, it has the stock style filter/pressure regulator combo as well. I think it's running at about 4 psi, but I'll check this afternoon just to verify that.

 

[volare 77]

You should be able to run a little more pressure with the holley. You may be running out of gas and causing the popping.

 

[9secRR]

ditch that carb and put on a 750 DP holley. 3.55 gears is fine. get a 3800 stall converter and watch the ET go down.

 

[old yellow 78]

I built a 360 for my Volare sedan

Hooray! Finally a 4 door sedan!! Lets see some pics!

 

[Duke5A]

Fuel pressure needs to be around seven or eight. 22 degrees seems to be a lot of initial timing for a factory stroke small block as well. How did you set the base timing?

How are the plugs burning? Without an AFR gauge reading the plugs is the only way you can narrow your jet size. Reading plugs for idle and part throttle isn't hard, but WOT will require you to run a full throttle blast and shut down the engine immediately after - pull a plug or two right after that to see.

What kind of exhaust? My 512 stroker lost 35 wheel horsepower hooked up to 2.5" dual exhaust.

Sounds like a very cool daily driver. Would love to see more photos.

 

[Oldiron440]

One more thing, you might want to check the wheght on your car, my 76 Volare Coupe /6 manual trans plain jain was a little more than 3500 lbs without me in it. So you could be making more power because you under estimating race weight.

 

[charlesvolare]

Hooray! Finally a 4 door sedan!! Lets see some pics!

I'll get pics uploaded when I get a chance

 

[charlesvolare]

Here's video of two of the passes:

 

[charlesvolare]

Fuel pressure needs to be around seven or eight. 22 degrees seems to be a lot of initial timing for a factory stroke small block as well. How did you set the base timing?

It idles like crap with less initial timing. Just a lot of trial and error with timing and carb adjustment to get it to idle the best.

What kind of exhaust? My 512 stroker lost 35 wheel horsepower hooked up to 2.5" dual exhaust.

It has dual 3" exhaust with summit turbo mufflers and an H-pipe, dumping in front of the axles. At the strip it was straight headers

 

[Duke5A]

It idles like crap with less initial timing. Just a lot of trial and error with timing and carb adjustment to get it to idle the best.


It has dual 3" exhaust with summit turbo mufflers and an H-pipe, dumping in front of the axles. At the strip it was straight headers

That has got to be loud. You use this as a daily? I must be getting too old.

Did you degree the cam when you installed it? I just can't get over the 22 degrees initial. Wonder if the high amount of initial timing is required to compensate for a cam that is retarded.