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Horse Power Opinions

Junky

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Was talking with a Mopar guy about my Coronet's 383 horse power. I'm hoping at least 370? What do you think?

Hughes cam: 229/242 at 0.050, 0.518 lift with 107 LSA installed at 102°.

346 heads that have received porting, blended bowls, 3 angle 2.08/1.74 valve job, milled 0.030 with steel shim head gaskets.

9.2:1 compression.

3310 Holley 750, secondaries fully open by 6k.

Edelbrock RPM intake with 4-hole half inch spacer.

MSD ignition.

Schumacher Tri-Y headers, 2.5 exhaust pipes, x-pipe, free flowing mufflers.

Fan clutch.

Denso Alternator

Windage tray.

180 thermostat.
 
The compression needs to be closer to 10 to 1.
 
The compression needs to be closer to 10 to 1.
I posted this question on one other Mopar web site. Together with you there have been 360hp, 370hp with 9:1, 400 with 9.5:1 and yours 370 with 10:1. I ran a Dyno program that indicated 392hp with 9.2:1. I guess it's somewhere between 360 and 400. :eusa_think:
 
Only way to tell true HP is to dyno the engine....but why are the secondaries so late? I want them to be open as soon as possible without bog and that should happen well before 6k...
 
Only way to tell true HP is to dyno the engine....but why are the secondaries so late? I want them to be open as soon as possible without bog and that should happen well before 6k...
So far I'm running the purple secondary spring. Secondaries start opening about 1600 RPM's and are fully open by 6000 RPM's. I just got this engine running, so I'll try the tall yellow spring next. That spring will let the secondaries start opening about 1400 RPM's fully opened by 5000 RPM's. I like the sound of the yellow spring. :)
 
The 3310 is supposed to be a really good carb but I have never liked the vacuum secondary carbs from Holley but really like the TQ. Yeah, the TQ has a learning curve but if you get your hands on the secondary air door tool to adjust the opening spring without a big hassle, then they are the way to go. Fugly (Damon) is the guru on the Eddy carbs. He also has a very good 'white paper' on carbs over on Style. Back to the Holley....Years ago I got frustrated with my 3310 because I could never get it to be consistent so I threw on a DP and never looked back but the DP needs to have some stall in the converter or a 4 speed for best results. Btw, I direct people to here too when needed....
 
So far I've been happy with the Holley. Weather here has been crappy. As soon as the weather gets better for dry roads I'll try the tall yellow secondary spring and post the results.
 
How does it run now? I'm thinking the try-y's are hurting you. Your cam with the narrow LSA probably comes on like a 2 stroke somewhere up high and that's more suited with a 4 into 1 header. More CR can only help with that cam. I ran a 3310 with an auto and a 4778 with a 4 spd on a 383 and both were great. I'm running a 750 AFB now on a 440 and I'm happy with that as well. I guess whatever works is the bottom line.
 
Before I had the XE262H Comp Cam. That didn't need a whole lot of air/fuel. I was running the brown secondary spring, medium heavy. With the new cam, the brown spring was not cutting it. The engine didn't start coming on until well above 3 grand. Would only turn the tires (275/60/15) over three or four times from a stop. So I tried the purple spring, medium light. That made a BIG difference. Now it comes on like a freight train, off idle. The first time I hit it from a stop it blew the tires off and the RPM's went straight to 5 + grand! It shocked me, so I pulled my foot out of it, fast. Now I have no traction. :) Tomorrow I'm gonna try the tall yellow spring (light) to see if the engine wants more air/fuel. As it is with the purple spring, it pulls hard to 6k, off idle. I really like it!!!

I'm gonna need some sticky tires. This new cam (Whiplash) improves torque way more than the XE262H did. One other thing. With the Comp Cam and brown spring the tires would chirp hitting second gear. Now the tires actually spin when hitting second. Did I say I really like this cam?

The 3/4 length Tri-Y's aren't hurting enough to speak of for a hot rod street cruiser.
 
Tried the tall yellow secondary spring today. Not as crisp as the purple spring, so I'm going back to that one.
 
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