Motor losing its Chevy Heart

[Devil Pup]

Guys idk why but it seems i put in a new motor "Twice now" with all the umph in the world and after a few months it just seems my 350 is losing power. its nothing special just a small black 5.7L running an RV cam, edelbrock performer rpm manifold, 600CFM Carb,HEI street fire MSD distibuter, Hooker Pro comp Headers, Accel plugs, Taylor high energy wires and a turbo 350 tranny with a B&M Street strip shift kit with a B&M Shifter. . . idk why but i keep frying plug wires no matter how i run the wires, the motor seems out like its just not all there. it hesitates when i push the gas, the kick just isnt there like it used to be and i really wanna know how to get it to run right all or most of the time. i want to be able to drive it daily without worrying if im gonna be stuck . . . any suggestions, should i run a MSD box for the ignition to gain the power i miss. or change my manifold, or poss change plugs or . . . . . any suggestions are helpful. i just cant seem to figure it out anymore. thanks guys.

[chevroletman223]

for the plug wires it sounds like your exhaust is running real hot which can be caused by retarded timing, you might want to check that. as for power loss, maybe you wiped a cam lobe or possible carburetor issues. It could either be not tuned right, or one time i had a brand new holley and after a couple weeks it started to run really bad so i took it apart and found alot of metal cnc shavings in the carb that apparently holley didnt clean out..... anyways it clogged one side of the carb and didnt let gas get to 4 cylinders. so i was only running on four cylinders. Plus i could never get my holley to stop leaking... since then i switched to edelbrock and i love it, never had a problem! Just a few thoughts. Hope it helped. Dan

[ripdog28]

Agree, check the timing And get your carb tuned AND get wire boots. From summer to winter, your carb usually needs some adjustments. Temp outside changes, there for the air density is a little diffrent and the carb needs a little adjusting.

[71tahoe]

Also make sure your plugs are gapped for an HEI.

[aboveall]

i had same problem with holly carb put brand new on and started running like crap took it apart and lot of metal fileings in it they dont clean them good enouph when put together funny you had the same problem to chevroletman223 happen to me twice but other then that i still like the hollys and i still use them

[aboveall]

also forgot to mention check all grounds make sure your grounded proberly

[aboveall]

properly my spelling sucks lol

[Devil Pup]

ya that makes alot of sense. The wires run close to my headers at certain points, i do have heat boots on those but they still fry. and as far as the carb thats something i have to have done? or is it really hard? how much should it cost to tune the carb?

[chevroletman223]

aboveall- yea apparently they dont clean them very well lol i switched to edelbrock because i found that theyre alot easier to tune, and i like the design where the gasket is above the fuel level in the bowl so it cant leak. But i guess its personal preference. And devil pup, ive never payed someone to tune my carb so i dont know exactly, but if i had to guess id figure an hour or two of shop time. and shops get around $60 an hour i think? so probobly around $100-120 but i dont know for sure. Or you could read some how to articles and learn it yourself and save some money and gain some valuable knowledge. its really not hard. Hope this helps. Dan

[ripdog28]

I have an excellent Carb article at home i will link once off work. You can do it yourself after reading it. it isnt as hard as people make it out to be. Should try tuning a 3.5cc Nitromethane race engine, way harder.

[knsmodels]

if it is losing power gradually I cant help but wonder if your cam is good....when I wiped a few lobes on mine it was a gradual loss until it started popping.....just a thought

[ripdog28]

Here... more of a tune up rather then a adjustment.

[ed2552]

Here are some wires that probably won't melt on you: http://www.taylorvertex.com/Products...i/fullMetal8mm . Although I do know some people who have had nothing but issues with Taylor wires, so take it at what you will.

[Devil Pup]

Im gonna do the "Tune up" lol and a new set of wires. . . hey ed2552 would i need the part #91001. . . for my 69 running a 5.7? and are they really worth the $166 bucks their asking for them? maybe new headers would be a better option? or?

[Devil Pup]

ok so today i messed with my timing a bit as well as the carb. I didn't delve all the way into jets and such just messed with the mixture screws on the front. It seems that it helped a lot. it allowed me to turn down my idle and it stays running nicely. it has a slight hesitation when i hit the gas but seems like the power is there again. could this hesitation be timing? should i run my vacuum advance or plug it? also i pulled a plug and its pretty black. i know that's bad but i cant afford to change them until pay day. could that also be the issue with the hesitation?

[johndawelder]

You need to run your vac.advance.Unplug it from distriutor and plug the hose when you set your timing though.Sounds like carb was running rich if your plugs are black.Turn your idle screws all the way in (be gentle) then turn them out 1 1/4 to 1 1/2 turns out.This will get you real close.

[HighwayHum72]

keep messing with it dude. mess with it all the time. take those valve covers off everytime and get to know all 16 pieces and their personalities. don't go anywhere without the 5/8", 9/16", 7/16" flathead, allen, pliers, torx bits, sparkplug socket, some racing oil, and take your calibration kit and use it until you can pick out the orange springs and the 7037's with a blindfold on...and don't be too lazy to get to the jets. vacuum leaks can be real hard sometimes too. make sure your floats are right and pressure not to high. a flashlight is muy importante amigo and a rag maybe and make sure your hazards work ok and hopefully you got top posts so you can just twist off that negative wire while you turn the crank and look at the rotor and pop the cap back on. you'll get it after awhile. maybe try out a bigger cam and get yourself a mechanical dizzy and some light springs. keep on listening, smelling, twisting and feeling everything until she acts the way you want. unless shes sticking through the firewall that chevy 350 has a lot of heart.