After much excitement and anticipation, I got my camaro back today having had the 305 removed and a freshly rebuilt 350 (.040 over) installed- only to discover LESS power to the wheels. I'm not sure what the problem is, but I think I can say that I definately have less power now then when I had the 305 (b4 it blew up). In addition, it stalled at low idle today in a parking lot. Something is definately out of tune.
My theories:
#1- I know they kept the 305 induction, this produces a '91 350 engine with a TBI system off my original 305. From what I can tell, there never was a combination of 350/TBI for those years, they were all TPI.
#2- Despite running fairly smoothly (at least it sounds smooth), the computer or chip remains that of the original 305 as well, Can someone confirm if all the electronic controls were compatable?
#3- The cam or other timing parts such as a distributor, may not match up.

this engine has remanufactured heads, timing chain, block, new pistons, rings, water pump, thermostat, etc., etc., etc. I p;an to update the Eprom when I get the chance. Any ideas on what's holding back the power in my 350? Thanks for any help! Especially things to look out for (or test)! I was going to get SFC's to deal with the added torque and power, but if this is all I get then forget it! Thanks again!
-Kevin

 

if you have the tbi crap then you need a new chip the stock one with a 305 will hardly support that a 350 is wayyyy out there try getting a 350 chip and see if that improves the hp if not find out what they put in the engine, and let me know i had tbi and dumped it for a carb and to tell ya ill never look back!! let me know what happens the stock chip feeds the engine exactly like the 305 because thats how its programed. the injectors are 19# units from the factory they SHOULD be enough for your mild 356 the hp loss is becuase of imprpoer adjustment on the computer and tuning check the base timing by un-plugging the brown distributor lead and look at the timing mark!

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89 firebird formula

356 10.7:1compression
comp cams xe262 cam
performer rpm intake
#1405 edlebrock 600
434 casting completely redone with bronze guides and 202/160 valves 64cc chambers.
msd 6al
h.e.i. proform 50,000 volt vac. advance ditributor
700r-4 with 3.08 first gear and 3.23 posi 7 5/8 rear end.
b trans shift kit(will kill shifts...suck dong!!)
shorty heddman hedders with custom 3" pipe y-pipe back(no damn cat!) with 40 series flowmaster!


future mods: 406 roller REALLY REALLY REALLY RADICAL!!!!!

 

Another Case of a Hack Mechanic Job.




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60 Ranchero - Project ( Money Hole )
85 Sport Coupe LG4 - Daily Driver

Just another Hot Rod kid, or thats what they all tell me.
Livin' the Stereotype

 

There were plenty of 350 TBI trucks and full-size cars in those years. Their performance didn't exactly light the world on fire either. The TBI system itself, as executed by GM, was not designed in the slightest for performance anyway; basically it's a grocery cart, nothing more. You just have a little bigger grocery cart now. The controls are "compatible" in the sense that they fit and all that, but probably not appropriate to your intentions.

I would suggest first that you go to the boneyard and get whatever is different off of a 350 TBI truck or Caprice. This might include the throttle body & injectors, maybe the manifold, chte chip from the ECM, etc. You'll almost certainly need an AFPR to have any hope of really tuning it perfectly. Remember: power comes from burning gasoline molecules; if the FI is inserting the same number of gasoline molecules it always used to when it was a 305, you're going to get exactly the same power. That relationship is so trivial it's easy to overlook.

What kind of a 350 is this? Pistons, heads, cam? You may have done something like gone from a 9.3:1 305 to a 8.5:1 350, and slightly lean (grocery cart mode) to pitifully lean (wrongly calibrated grocery cart) all at the same time, which would certainly make it run no better than before. Without knowing what cam you've got, any attempt at a custom chip is going to be rather frustrating, and it's not impossible that you've got a worse cam in the 350 than you had in the 305 too.

So there's lots of things to look at before giving up on it. I think all of us that swap motors have been where you are now, at one time or another; you just gotta identify the possibilities and work through them. Plus, what you're starting out with is of such a nature that it's automatically a disappointment, but there is at least a path for you to make it better than the factory's lame product.

Also, a brand-new motor will take a few thousand miles of proper break-in before it develops its full potential power, so what you have now will grow a little over time.

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"So many Mustangs, so little time..."
ICON Motorsports

 

GEESE JUST RUN A CARB...YOULL NEVER LOOK BACK!!!!
MIKE

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86 camaro:was a v6 car,now its going to be a v-8 5.7l!!
350:cylinders bored .040 over.a little over 9:1 compression(getting a blower some day when im rich lol)line bored.deck is milled a little(was pitted)
trw forged pistons with summit stage 2 polished rods with arp bolts.
194? intake valves(not 2.02( ),pocket ported,gasket matched,and polished ports,old vette intake with new zinc 650 holley

ase certified for a few years,learned alot though

working on freakin NEONS ,cirruses,tauruses,cobras(well` at least they look nice lol)and intrepids all day makes me drink too much
good job security though

im always on the lookout for cheapv-8 t-5,s
and t-56 setups.they must be cheap.i dont care of they need rebuild,as long as they arent totally blown