low end lag after H/C/I

[SPEEDYLIFSAVR]

I recently did my H/C/I swap .(Mods in sig) I was very pleased as this was my first time , I did it myself and I had visions of oil and coolant just spewing everywhere upon my initial startup . but everything went very well .

started right up no leaks !!

I hand tuned it with 14* timing and 38#'s fuel pressure . after initial beak in and oil change I took her for a run . The sound is absolutely unbelievable !!!


I was a little disappointed with the low end . before 2800 rpms there is a noticeable hesitation . after 3000 its just pulls hard all the way to 6000 , very impressive however I am concerned about the loss of low end . I messed with timing and FP it seems to just want to take timing , I had it as high as 20* with spout connector out without any spark knock . Does this seem right?

I backed it down to 18 with FP at 44psi vac line off . still hesitation in low rpm's . is this just a product of my set-up or should I be looking for other problems ??

 

[Foxfan88]

the gt40 p are a higher flowing head with bigger valves which favor higher rpms. (the intake at least, exhaust on Ps are smaller but flow better than regulars) and the cam which shifts up the power and the intake which contributes also. i u want low end back. tear back down and advance the camshaft 4* and you will get some low end back.

 

[Foxfan88]

opps dbl post

 

[GTOreturns]

What headers and mid pipe r u running? MAF/TB ?
Oops,scratch that. Just saw your sig.

 

[GTOreturns]

Is your MAF calibrated to the 24's??

 

[SPEEDYLIFSAVR]

Yes , MAF is calibrated to 24's

 

[Brn N Rubr]

Make a video and "take us for a ride" so we can hear what it is doing.

 

[DMAN302]

If your getting up to 20deg without detonation on iron heads I am willing to bet either your reading it wrong, or that balancer has spun its self around a bit. I wouldn't run anything over 14-15 on irons. Fuel pressure should be set at 38-41 max with your current setup...44 is too high. Have you cleaned the meter or is it new?...some aftermarket mafs tend to run on the rich side out of the box and dirty elements will play games with your performance, you might benefit from a few pulls on local dyno to check A/F. As stated earlier you could play with the cam timing but dot to dot the E cam will often be a little flat down low....hesitation though should not be a factor. I sugest you find TDC and check your balancer marks against it then try 14 deg to start, drop your pressure, and make sure to pull the codes to see if anything is up there...sometimes sensors can get a bit cranky when engines are taken apart and put back together.