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Discussion Starter #1
My mustang made 290RWHP and 306TQ on a dyno jet. I was expecting to be at least 315-330 any ideas what's holding me back. I have trick flow 170cc track heat heads w 1.7 Rr, b cam, unported weiand stealth intake, holley 650 dp. The heads were milled to a 58cc combustion chamber and the timing was set to trick flows specifications, the carburetor jets were changed to 70/71 and the A/F was perfect throughout all rpm. The dyno chart show peak hp at 5800 then it starts dropping off! Could it be that I need a victor jr intake, bigger carb (670 demon), or maybe just a carb spacer on my weiand intake. Am I expecting too much from a b cam? Although I have seen a few guys running a b cam make 315-330 RWHP. I plan on adding underdrive pullies soon. At this point I just wanna break 300RWHP. Can anyone tell me what could possibly be holding me back? Also could it be that I need to port match my weiand intake!
 

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What curve was the powerband? Was it linear and rising at a steady rate, or did it level off anywhere?

290 to the wheels is pretty good, just know you don't have a heavy hitter. 290 to the rear means it's around 330-340 at the engine and that's respectable.

The B cam isn't necessarily a problem, but you could get more with a better cam in there. The B is nearly 25 years old, there's far better sticks nowadays.

You want more power, you have to get more aggressive with what parts you have. That would mean getting bigger heads like the 180-195cc range, rather than the mild 170s.

Most of all, don't get hung up on what dyno numbers you have because it's just a number. How does it drive? That's what's more important.
 

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Discussion Starter #3 (Edited)
It had a steady increase but not linear up until 5800 and the dyno operator said he thought I need a single plain intake or a 1-2" carb spacer on my weiand I wish I could post dyno sheet but working off my iPhone. So shoul I be ok with my dual plain or is there more to be had with a victor jr and demon carb because my neighbor is selling both!
 

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If you want horsepower, then the Victor intake would work. It'd help, but then a cam swap to better match the powerband of that intake would be needed. It goes 3500-8000 and the B would be a mismatch for it.

The B has a peaky powerband, peak torque at 3300 and hp at 5100. Get a cam that will go up to 6200-6500 would get the power you want, that would be the recommended limit for a stock bottom end.
 

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Discussion Starter #5
Cool thanks I think I'm just gonna throw in a OTC cam. Any suggestions for a cam trick flow says I can go 540 lift at max with stock pistons. Xe274hr/xe276hr/xe266hr with 1.6 Rr of course!
 

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Those numbers are not bad. What kind of transmission do you have? Take it to the track, your trap speed will also tell you how much power youre making.
 

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Discussion Starter #8
It's a stock WC t-5. So do you think underdrive pulleys will get me to 300? I thought it's worth a shot since I already have a 3G alternator and no heating problems it could only help!
 

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The UD's are not worth the headache. Your cam is killing you, and the victor intake would be better. Id predict a 320 rwhp with those. Port matching may help also. The numbers on a dyno jet are not accurate and are usually overrated. There is more power to come out of that setup.
 

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Given he is likely staying 6500 with cam choices and stock short block - your best bet would be the Edelbrock RPM Airgap manifold. Dyno tests show RPM Airgap stays with the Vic Jr hp wise until about 6000, but with much more torque down below. Gasket match intake and heads. Is your LT headers at least 1 5/8"? Your fine carb wise. Pullies will help.
 

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Discussion Starter #11
Yes the LT are 1 5/8 and I think I'm gonna take the weiand stealth intake off and port match it to within 1/8 of the heads so the ports on the heads are barely bigger and see what happens. I'm still gonna throw some underdrive pullies on though! What do u mean by headache of underdrive pullies install or heating and charging issues
 

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I have heard people having great results with the weiand x-cellerator intake with TFS170 heads, its a single plane but it is small, compared to a edelbrock single plane. I also was told to get the older version, the new ones arent made as well.
I ran one on an old engine i had, it was a 306, tfs170s, 1.72rr, custom blower cam(but no blower) it the cam was in the 218/220ish dur and 540ish lift, it would pull to 6300rpm great. i was also running a 650 speed demon.
 
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