Hi I just got my rebuilt 305 installed and it has a mild cam and a wiend x celerator intake with the tbi to carb intake adapter plate but other than tthat its stock. I set the timing and its hard to keep it idling but I took it for a spin and it just has no power and just boggs down like something is keeping it from doineg anything at all. I forgot to mention its in a 92 caprice. Any help would be awsome thanks.

 

Check the fuel pressure. You'll probably have raise the fuel pressure as that intake moves alot more air.
Is it possible that harmonic balancer has slipped? If so your timing maybe way retarded, try advancing it. Make sure it advances when you rev the engine.

 

Not enough info-

What cam?
What tuning have you done?
Fuel pressure?
Cold air mods?
Performance chip?
Rear gear ratio?
Tire size?

anything else you can think of would help us...

 

The gear is 3.08
The tire size is 255/35/ZR20
The cam is a comp extreme energy the intake lift is .447 exhaust is .454 the intake duration is256 and exhaust is 268 and the lobe seperation is 110°. As far as tuning ,chips, cold air mods I havent got there yet I didnt know if something minor could be doing it.

 

Tune tune tune along with an exhaust. From what I understand tbi won't be easy to tune with your 110 lsa cam.

 

yeah the 110 LSA is a problem. Look into getting a chip tuned for you, or buying self tuning program like dynamicefi.com flash EBL

 

Datalogging + Tuning 4 sure. Does it run better > 160F or < ?

 

No it runs alot worse

 

worse which way over or under?

 

Over just as soon as it warms up it gets pretty bad

 

All adds up. OL it runs off a fuel map based on RPM/MAP- A/F. No 02 sensor feedback. CL it uses BLM and a fuel map that is not correct for needs of motor. Also the cam may be sending more 02 to NB sensor causing ECU to add fuel.

 

Would that have an affect on it even while im trying to drive it

 

yes it would. Idle as well. you need to go to DIY board here and study the stickies. also one of the best is TBI sticky "free tune".

 

Can I tune it with just the ALDL cable and a program

 

I tinkered with it yesterday and took it for a spin and it just boggs down, the rpms wont even climb when it gets into second gear.

 

I think the OBD 2 vehcles allow that. Ours is 1. Only tune by a wire to ECU that I know of is provided by dynamicefi.com. I have that in my car. My ECU was modded by them(RBob) to allow a flash to update ECU prom in about 3 seconds. It also makes corrections to bin as I drive. If I accept corrections I flash it into ECU. Megasquirt way be similar....

edit: consider making buying an aldl cable and dowload winaldl(free) and report values to us. you have a laptop?

 

I do not have a laptop

 

Is that something that cam be tuned by that program

 

go to their site and read up. ebay for used laptop. serial port favored over usb.

 

Would swapping cams make these issues go away

 

what size cam do you have now?

is intake a single plane? If so it may need tuning as the intake internally is larger on surface area. Needs more fuel in AE or aka pumpshot.

 

The cam has 447/454 lift with a lsa of 110° and the intake is a low rise single plane.

 

Comp Cams Xtreme Energy 256, 12-234-2

http://www.compcams.com/technical/Dy...56H-10_001.asp

 

Not terribly large but enoung to require a tune.
It will require tuning due to single plane as well....

 

I also have a dual plane holley and this motor is an early non roller motor

 

Ducking for cover but from reading it id bet the simplicity of putting a carb on it will make up for maybe 1-2MPG difference.

http://www.nationalcarburetors.com/

Great place, give them your engine and car specs and they will send you one you can just drop on and go. You will just smile every time you stomp it.

very affordable too, one could resell their work even with the core charge n make money.

 

I have the tbi on it with an adapter plate but do you think going with a carb would be better.

 

if you do not want to learn to program yourself... or pay for a dyno tune.. then yes a carb is your only alternative

 

I wouldnt mind knowing how to do all of the computer work but I just dont have the funds todo s, it took me a year to get where I am now.

 

call national and get a carb, their lvl2 performance qjet is under $270 shipped.
Just bolt it on and go.

autozone or local will charge more then $300 for a stock tune carb you will have to fiddle with.