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Author Topic:   new engine troubles
Shortfuse15
Dirt Full Roller

Total posts: 37
posted April 04, 2005 09:52 AM  
I just built a 350 and im haveing a bit of trouble getting it locked in. All i can get out of it is 5000rpm. up to about 3000 it pulls awesome, but anywhere above that it starts to stumble and wont go over 5. I messed around with timing, jets, reset the valves. what am i missing? sorry, im new at this.

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted April 04, 2005 10:02 AM  
is it a hydraulic cam?

what kind of springs do you have on the heads?

Shortfuse15
Dirt Full Roller

Total posts: 37
posted April 04, 2005 10:12 AM  
yes hydrolic, 484/490 lift. i have z28 springs. (100#)

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted April 04, 2005 10:17 AM  
Could be floating the valves, 100# on the seat isnt much for that rpm. This would be my first guess.

Could also be getting lifter pump up.

BrianW
Dirt Freak

Total posts: 385
posted April 04, 2005 10:48 AM  
Have you checked all the ignition components? What are you running for ignition?

Also - do you have a good battery & alternator setup, and good connections - low voltage to the coil or module can cause this too...

Shortfuse15
Dirt Full Roller

Total posts: 37
posted April 04, 2005 01:33 PM  
im running a stock distributer thats locked up and an accel super stock coil. I got a 1000 cca battery but im not running an alternator. The battery could have been a bit low. I should be still running a ballast resistor to the coil because im running points, right? how would i know if im floating the valves?

Shortfuse15
Dirt Full Roller

Total posts: 37
posted April 04, 2005 01:39 PM  
my bad, the z28 springs are 125# on the seat

dirtbuster
Dirt Forum Champ
Total posts: 2007
posted April 04, 2005 02:54 PM  
do you know what they are at full lift??

do you run a high volume oil pump?

Shortfuse15
Dirt Full Roller

Total posts: 37
posted April 04, 2005 03:29 PM  
full lift is 360#
no, im not running a high volume oil pump

Shortfuse15
Dirt Full Roller

Total posts: 37
posted April 04, 2005 03:56 PM  
whoa whoa whoa... hold on... i was looking at the wrong deal here. I got the "z28" "100 pounders" whatever you want to call them. I would assume that at seat they would be 100lbs, i have no idea what they are at lift. sorry for the confusion

Donnie Ross
Dirt Freak

Total posts: 264
posted April 04, 2005 07:47 PM  
first things first you said points? did you use parts store replacements or high tension if stock replacements they could very well be floating on you at higher rpm.what is your dwell setting? condition of the point cam?unless you have to run points an hei would be a much better option, hope this helps.

Shortfuse15
Dirt Full Roller

Total posts: 37
posted April 04, 2005 08:28 PM  
yes, its a stock replacement, brand new. points are set at .018

Shortfuse15
Dirt Full Roller

Total posts: 37
posted April 04, 2005 08:37 PM  
i think it just hit me. When i hit 3k, the timing light goes out. when the timing light comes back on, she runs great. floating points = misfire. i think im gonna swap out to hei. talk about a brain fart...

racer2
Dirt Freak

Total posts: 352
posted April 05, 2005 08:03 AM  
sorry didnt read all of posts

[This message has been edited by racer2 (edited April 05, 2005).]

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