Power loss from new Cam or Convertor 2 small?

I have a question. This is my setup... BBB 455... Edelbrock intake, ported polished heads, HEI ignition, TA413 cam, Holley 750 cfm.carb; 9.5:1 compression ratio, Built TH350 transmission with shift kit. 4:10 rear gears? (4000 rpm @ 70mph)

I had a smaller cam before . I was able to do burnouts no problem until I got the new cam!
It hooks up like crazy now. (I also added a rear sway bar)
Would a new Torque convertor help with power? I have basically a stock convertor now. I ordered a 2800 stall convertor in hopes it would pickup some power. Is this a good street convertor?
I thought it would be super powerful after the cam swap but seems a little less than before. :-(


I have also noticed when excelarating hard and I get to about 40mph with it still floored it sounds like the car is dieseling or lacking fuel? What's up with that?
Thanks for any ideas or answers.
Lost in WI;
Mike

 

Install a fuel pressure gauge and see what you have under varying conditions.

I believe there's an electric one available now, but I prefer mechanical ones.

Be sure and run a fuel pressure isolater if you do run a mechanical gauge inside the passenger compartment.
In fact, I'd run one even if the gauge was outside on hood or cowl.
Autometer has a nice combo package with gauge and isolater.

There are smaller fuel pressure isolaters out there than the Autometer isolater - which seems to be unavailable by itself.
My local speed shop was able to get one for me - which was nice since I run S-W instruments and already had the gauge.

A fuel pressure gauge along with a vacuum gauge will tell you a whole lot about what your engine is doing as well as what it wants.

 

the torque curve moves up as the cam gets bigger, so if you have a stock converter the moter is struglging to get in its power band, the 413 would be at least 2000 rpm, i have similar 113A cam, and run a 4000 switch pitch,and 373 gears, even with the low stall at 1500, i can light the tires up even at 30 mph. from a dead stop there is absoluty no traction on street tires. just my 2 cents

 

..........

That 750 Holley is hurting you even on your mild combo. Did you re-jet the carb for the new cam? How about ignition timing? Try at least a 1" open spacer and/or a 850.

A 2800 should wake it up.

 

Exactly what I was thinking.....not enough carb.

On the converter side - I drive alot on the highway so I wanted to limit how much the converter was slipping at my "usual" cruise RPM. Mine is 2200-2400 stall loose 11". 70mph on the highway and Im at 2600rpm

 

Thank's

Great advise guy's I really appreciate it.
I have a new Holley 870 that I just recieved with a heat spacer and the new stall converter will be arriving shortly.

I blew a header gasket tonight. Grrr! So I'll be wrench'n tomarrow. oh boy!
The timing I am not real good with, still confused about it all.

After cam break-in should the timing be adjusted?

No the 750 carb was not rejetted. The previous owner just bolted it on the way it came.

Thanks for your time and help guy's!
Mike

 

Timing

With a larger cam you want to make sure you have 12-14 initial timing with 36 total. Larger cams feel real weak at lower rpms without enough timing.

 

Your SCR is kinda low for the 413. 10:1 would help. Did you degree the cam? Where did you put the ICL? You might want to try advancing the cam some to get a little more bottom end torque.

 

I had a shop put the cam in. Not sure if it was degreed or not.
What is ICL?
How do you advance the cam and adjust the timing? How do you know what the timing is reading? I have seen it done but do not understand the concept.

 

I'd bet the cam was not properly degreed.......99 out of a 100 times people do not degree the new cam.

 

I installed a 413 cam in my car this past winter. It was sick with the stock converter. I installed a 2900 stall and couldn't believe the difference. The car came alive! I did need fuel supply upgrades also. Good fuel pump, big carb and the right amount of timing with your new stall converter will make you grin.

 

Yeah I doubt it was degreed also.

Thanks I sure hope it comes alive. I should have Tri-Shield Performance toon it for me next spring.

It's amazing how many people are Chevy "brain washed."
I ordered a new header gasket at the local parts place and they got me manifold gaskets for a 454! I said Buick 455 Header gaskets! So I'll wait on TA and get the right thing. Thanks to them we have a good source to go through.
Mike

 

ICL is "Intake Center Line". It's an indication of where the cam is degreed at. You degree it while you are installing the cam by using a degree wheel and dial indicator. It's common for the cams to not be degreed correctly if you just use the dot-to-dot method.

 

Thank's

Thank's Scott.
Now I know what I.C.L. means!
Mike