Loosing power up incline

[brian72]

Some specs....
Motor - 302
Carb - Holley T/A 470
Tires - 35x12.50 BFG
Drivetrain - 3.50 gears - 3speed

A couple times going up this incline I would get up about 1/2 way and run out of power and or any forward movement. A bunch of times it died and I had to just coast back down to the bottom. Then other times it made it all the way.

I know the motor and the 3.50 gears don't help, but sometimes it worked. Just trying to understand why sometime and other not?

I Made it..1
I made it..2

No power..1
No power..2

 

[trailpsycho]

It seems like when you made it you had momemtum on your side, when you didnt you didnt have as much. I would guess that youre probably not in the optimum gear and having no locker and the 3.50 gears are further hurting you. I believe that if you were in a lower gear with a bit more consistent throttle, that you would be fine. 35"s w/ 3.50 is asking alot from your motor. THe motor sounds really good though. I had similar experiences with mine...much bigger longer hill climb though...I needed to be well into the throttle or it would bog down....especially with crappy ATs (MTRs made a difference; didnt need as much throttle b/c the traction was that much better so less wheel spin). I think not having any locker in the rear is hurting you a bit too, if you look at the 2nd vid, once your forward momentum stops, nothing is being translated to the driver side tire...my guess would be that the PS is probably spinning...just not with enough to get you up and over. It may require a bit of tweaking on your carb too...I realize its a TA, but its still a Holley and they need to be adjusted-typically. Are you running a C4, then the right gear comment I made is useless and its all about your axle-gearing.

 

[kbronco]

I've got about the same equipment as you and the same problem and the only thing I can figure is the 3.50 gears. Mine hasn't died on an incline yet, but its pretty doggy and lose a lot of speed. I've got 33's instead of 35's, but sounds like thats about the only difference.

 

[Sac '68 sport]

will it make it in 4 low? Hard to tell, but the first one where you didn't make it looked like it quit before you were even really into the hill. Is your carb flooding out (fuel slosh) from all the bouncing? Might try lowering the levels in the fule bowls, see if that helps.

 

[brian72]

this was all in 4L - I could get to the speed quicker that way.

 

[Duke Nukem]

Even with 3.50 gears you should easily make it up that dinky hill. When you say you lose power I'm assuming that you are losing engine power. Does this only happen on hills offroading or does it happen at other times, for instance on the freeway going up a grade?

 

[brian72]

Even with 3.50 gears you should easily make it up that dinky hill. When you say you lose power I'm assuming that you are losing engine power. Does this only happen on hills offroading or does it happen at other times, for instance on the freeway going up a grade?

Yes - that was a dinky hill. I was hoping to just crawl up that thing in 4L / 1st gear. But I had to hit it to get up because I would Lose engine power, and yes...somtimes engine even dies.

Not too bad going up grade, normal loss of MPH going up hill, but not too doggish.

 

[TJK74]

Definately sounds like a carb issue.
What fuel pump are you running on that? If its a High volume they like to put out more pressure than holleys are happy at and blow fuel past the needle and seat. A pressure regulator would help in this situation. Another sign of this is if its running rich or loading up at an idle.

Check the float bowl level this could be part of the problem and you could be getting some slosh but it shouldnt be enough to kill it on a mild hill laik that being that the T/A has the crossed ove vent tube.

Can you get it to Idle steady on an angle or steep incline or decline?

 

[bronko69er]

I did a lot of wheeling with my stock setup like yours with 33's. Only time I had a problem was on a really steep incline (much steeper that that little hill) my edelbrock would start to flood. That was before I installed the offroad springs. Even with the gearing/tires you have, in 4-low 1st you should be able to "crawl" up that small hill at just above idle no problem without it dying. I agree, its likely a carb/fuel problem.

 

[brian72]

Definately sounds like a carb issue.
What fuel pump are you running on that? If its a High volume they like to put out more pressure than holleys are happy at and blow fuel past the needle and seat. A pressure regulator would help in this situation. Another sign of this is if its running rich or loading up at an idle.

Check the float bowl level this could be part of the problem and you could be getting some slosh but it shouldnt be enough to kill it on a mild hill laik that being that the T/A has the crossed ove vent tube.

Can you get it to Idle steady on an angle or steep incline or decline?

Fuel Pump - Carter P4070 http://store.summitracing.com/partdetail.asp?autofilter=1&part=CRT-P4070&N=700+115&autoview=sku

Sometimes it would not crank on the incline. When it did...it would blow black smoke. Did not think to try and see if it would idle on angle.

Called holley and they want me to send the carb back....

 

[RRRAAAYYY2]

While you have the carb off, put a fogger plate underneath it before you re-install it.

 

[cj54]

The carburetor float might be tweaked sideways slightly, just enough to cause it to hang against the float bowl due to the bouncing going up the hill.

 

[BUCKETOBOLTS]

Before I sent it in for repairs I'd try to adjust the primary float. To adjust use a 5/8 wrench and a wide flat screw driver. The screw is actually the jam nut, so hold the nut still with the wrench to brake the screw loose. Sounds like your float level is high. To adjust turn the nut clockwise. I would move it 1 to 2 "flats" of the nut at a time. Adjust then try it out. If it needs more try again. But It probably shouldn't need more that 2-4 flats.