bensbaby

I just built the engine last winter and just spent 2 months installing it

no codes I got 10kms on it idels fine
as soon as you go to accel just a bit it misses 1 or 2 cylinders
I have brand new 8mm wires
brand new cap and rotor today did nothing
new plugs with new alum heads I got

is making me crazy
this is a 10.5 comp 383

and it sould ne running amzing
not horrible

I have checked the firing order 4 times in the last week

the one thing I did was I know the timing was set to 7 to 8ish

and I had the chip burner guy burn me a chip

it feels like its missing when you go 1/4 throttle

and im about to go to a boost leak test just to see if I can hear a vacuum leak anywhere

don't have a cat either

can my valves be adjusted to tight causing missing

or just no power

the only thing I did was bypass delete my fuel filter sat and it helped a lot I can actually accel now

I have new 30lb inj that where brand new rebuilt I got on ebay

should I take the plugs out and inspect them

and should I do a compression test????

does anyone know if my valves are to tight would cause no power

maybe my fuel pump is old and dying

pls anything guys

im lost scratching my head

Abubaca

iTrader: (3)

Was it running fine to begin with, and this problem is new, or has it been doing it all along? ....once you get past 1/4 throttle does it run ok, are does it feel bad at everything beyond 1/4 throttle? ...is the tune done via mailorder, or was it dyno tuned/street tuned in person?

mmadden55

vacuum leak, not enough octane and maybe just detonation. Try some octane boost if that doesn't help look for a vacuum leak or a loose plug wire.

Abubaca

iTrader: (3)

What kind of intake? TPI/Multiport? TBI/throttle body based?
Check your fuel pressure and watch what it does while running....and when you run into that rough spot. Should stay fairly constant, but slowly rise with RPMs. It'll always fluctuate a little, but if it's TPI based, you'll want about 42 or 43 at WOT and mid 30s at idle. Again, they're all slightly different at idle, but if you're at low 30s or lower....and pressure doesn't rise as throttle is applied, that's definitely a fuel problem. 30 pound injectors are probably ok, but even if they're a tad small, they should be MORE than enough to handle normal driving duties, and at WOT, they'll probably be just a little over 80% duty cycle, which is about as high as you wanna push em. Stock original pump could easily be the problem, or at the very least, could easily be a problem in the future, even if it's not THIS problem.

bensbaby

my chip was mailorder

it was running with my 305 tpi t5 it ran amazing
that's why I did the swap
I have had the car im my family since brand new 305 t5 88gta

now its a 383 t56

1/4 up throttle it just misses and cuts out

I am still breaking the engine 10kms on it

it has 91 gas that's all I have here

tpi with the 305 but now I have a stealth ram intake and stock tb
I have a 44psi adjustable aem fpr with a gauge

and I have a wideband 02 in a gauage pod with a vacume gauage

I also have a chevy perf lt1 hot cam

it just feels like it needs spark plugs bad

maybe I have a bad plug

????

im gonna go do a vacuum/boost leak test first

but I wanted to know that if I adjuted my valves to tight would they miss and feel like no power

it also seems to be ideling kinda high and my vaucume gauge was -12 600rpm before and now its 800 -20
I cant seem to get to idel down/

bensbaby

If I pull the plugs and do a compression test I should have 210 10.5-1 right in all them
what if they are low from the valves somehow being to tight keeping a valve or to open

ideling the car runs perfely
it starts so fast turn key fast
and I have a new walbro fuel pump im gonna put in to
I was just trying to see if I could get it broken in to 1000kms

I have 10km

bensbaby

I use 91 I would have to drive 1 hour each way to get 94

mmadden55

Octane boost from the autoparts store I think you just have detonation.

bensbaby

ok I took out my 8 plugs one had a cracked all the way around porcin wiggly loose
I would have never put it on knowing that it was broken

do you all think that that could be it
the spark arcs out when you start trying to go

im gonna try to order them

but im sol for tonight

but I got the front 4 compression test closes to the rad
firewall
---- ----- I cant get to these without taking my fing header off which I have to do tomm
---- -----
205 205
205 205

rad
and I wll try the octane booster

does anyone know a good one that actually works.

bensbaby

my timing is still 7 to 8 ish not 6

it should be 6

that would make it knock less if it was

Orr89RocZ

iTrader: (20)

bensbaby

I will let you know how it goes

I do have a wideband

Abubaca

iTrader: (3)

I'm with Orr. I think it's in the tune. ....mail order is hit or miss. More miss. ....at the very least you'd need the software to at LEAST datalog and get back to the tuner so he can make adjustments.

bensbaby

this person I used did it perfectly the first time

and as far as im concerened he did a good job now

the spark plug prorclin was broken all the way around causing a short on the plug

I replaced it took it for a ride and no more missing at allllll

and I felt the power and 1/4 throttle
2000 to 3000

I havnt gone past it but I may tonight just go again

I have a mega header to head leak and when I drive it now for the last couple weeks I get baked

I got some 2007 remflex gaskets and once it cools off tonight im gonna go out again and maybe do I side tonight

its so hot and humid here today I want to puke out

bensbaby

scott Hansen.net is the guy I used

for a chip burner

auto_god

I'm curious if the spark plugs are the appropriate length/style etc for the aluminum heads you acquired. Some more detail on those may help.

bensbaby

i had them custom built from dw performance last year

hes the one who told me what plugs to use

and my cars not missing anymore

its gonna be a wheelie machine
runs like brand new

mad power

6250rpm redline

the spark plug was cracked and arcing out

sofakingdom

iTrader: (1)

*** 383 found under hood after brief search ***

Sorry, I just had to

Orr89RocZ

iTrader: (20)