Alright guys so heres my situation..
Please take the time to read

A few weeks ago i decided to finally swap out my old 305 TBI from my 91 RS and swap in a 350 vortec from a 97 1500 silverado.

Before



After




I got my car back about 2 weeks ago, the engine i swapped in is completely rebuilt with forged pistons etc..heres my complete new set up that i want verified to see if it checks out if not so that i can have it fixed.


-Vortec heads

-After market Comp Cam
specs found here:http://www.summitracing.com/parts/CCA-08-450-8/

Hooker 2460 shorties

Edelbrock Performer intake

Holley 650 4 barrel carb
info here:http://www.holley.com/0-82651.asp

2500 stall



The thing is im not so sure of how well the swap was done at the local shop i took it too... I went fully carburated instead of my old TBI setup. Since i got my car back ive put about 500 miles on it so far and heres what ive noticed.

Questions

1)On cold starts in the morning my car makes lots of popping sounds, so im assuming that maybe the carb needs to be tuned better? or is that normal? The popping stops once im driving its only on cold start

2) Since the swap, is overdrive still fully functioning?

3) What items do i need to double check on.Sensors? etc

4) is the valve lift on the cam adequate for the vortec heads?

5) I know the shop did some sort of fabrication with the TPS, using springs and the old TPS rod from my TBI, i know for a fact that the TPS is on there but what voltage should it be giving? Last i checked the mechanic told me that it was set up at its max reading.

6) What should my Timing be set to? I saw the shop "time" my car and they were just randomly turning the distributor and timing it by ear and i personally want to have it timed properly but i need a spec.

7) when i drop my car on Drive it hits pretty hard, when going into second gear it jolts u back a bit, although when the tps was added it did it a bit less.

8) Does spark plug gap size and all the original 305 specs stay the same?

9) About how many horses am i putting to the ground with my new set up? Was it a big jump from my 305? Ive really started to doubt myself, i spent about $2700 on this swap and im really hoping that i didn't make a mistake.

10) one thing i left out on the swap was the rear end gears, i figured i would swap em in later after the break in period, how big of a difference do they make? and are 3.73s the right choice for my setup?

I pretty much need to do a complete check on everything that was done to my car. I know the shop is legit and all but they are the kind of people that grow up with cars and don't necessarily do research on computers or look up specifics so i need to help them out a bit which is why im making this thread.

I have documented just about everything and can provide pictures and any info needed. I could really use some help from the pros here at TGO because even though my engine looks pretty and all it doesn't mean its running like it should.

Thanks for reading, any help appreciated.

 

First thing to do is lose the "triangle of death" air cleaner...

The choke may need adjustment.

Yes, but the TCC may not be, depending on what they've done.

Without an ECM there are no sensors doing anything useful.

The other way around is more of a concern. Is the lift available on the Vortec heads adequate for the cam. .560 is pretty high for unmodified Vortecs.


Not much point to having a TPS anymore, and there isn't one visible in your picture.

All the advance in at about 34-36 degrees by 2,000 RPM or so, depending on how the engine likes it without pinging.

What TPS?

Stock gap is fine.

3.73 are fine, you'll notice a big improvement from this alone.

 

The only reason i have that air cleaner is because of clearance i have stock hood and im afraid the others wont fit correctly.


How can i know for sure the choke is adjusted properly?

What should i do about the lift issue, what happens if i continue running the car with the current lift? Ditch heads? ditch cam?

What all does the ECM control now? just my gauges?

The TPS is on there but id have to take a better picture of it

So running on Overdrive still restricts my engine a bit? like previously on my 305?

Can you give me a little bit more of a noob explanation for the timing?


Thanks apeiron

 

that new engine looks really nice, congrats on the swap. I want to do the same with my 305 tbi in my 92 bird, whats the average cost to do this?

 

You can adjust it a bit for yourself and see if the cold start performance improves.

Supposedly stock Vortecs don't flow any more past .500 lift, so you wouldn't be gaining anything from the increased lift. That's assuming that the valve guides have at least been machined to deal with the physical lift limits.

The gauges are independent of the ECM. It won't be doing anything now.

That'd be good.

I don't know what you mean by "restricts".

Have a read through the old tech-article first https://www.thirdgen.org/hei

 

@sandiegobird thanks, the rebuilt engine cost me $950 but i bought a new intake aftermarket cam, shorties, and stall, labor was about 500 + all the little things ended up being like 2700 for it all.

@apeiron

-I just got done reading the tech article and basically what i got from that is that i need a non computer controlled distributor for best performance, correct? Right now im still using the same one i had on my 305, i had originally replaced it with one from jegs. The article said i need to get rid of pretty much everything computer controlled, what else should i look into replacing aside from the distributor?

-i shouldn't run into any major problems with the lift then? i just wouldn't get the full potential from the cam?


-by restricts i mean, will i still notice a decrease in power between overdrive and drive

TPS pictures; i took these after work so they are a bit dark.
The guy made a mounting plate for the tps, and used the tps rod from my old tbi unit.

 

if those vortec heads werent worked for higher valve lift you have some problems.. they are only good to about a .460 lift before you have contact between the spring retainer and the valve seal area....

 

you don't need tha TPS at all now... and the tranny may need to be reworked since it is no longer controlled by the computer either. I did a swap like this a long time ago on a crossfire to a straight carb. All my sensors went the way sid e except for the coolant temp sensor in the drivers side head which works your temp gauge. I completely removed the ecm from mine and had to rework my grounds because the main ground straps were cut or not there.. I can't tell if yours are there either.

 

So they've put the TPS on to try to get the ECM to keep controlling the timing and the TCC. I'd rather lose it and use a non-computer distributor and use another way to lock the TCC.

 

If they haven't beaten themselves to death by now, they've been reworked.

 

@ scamaro/apeiron

I know for a fact that everything was taken to a machine shop, however i dont know about them being reworked specifically for the cam i ended up with. Since i bought the cam after everything was back from the machine shop. ( i let the mechanic choose the best cam for the set up, originally he was gonna put an LT1 cam, but i asked for an aftermarket so he picked my current cam) ive questioned him about the lift before and he said not to worry about it that hes used that cam in the past.( but ive done my research on here and everyone said the lift should be in the late 0.400s not late 0.500s

Should i still worry about the lift or am i ok for now? I have a bit over 500 miles so far and i havent really noticed any problems.. yet. so im not sure whether to worry or not.

@drew its odd because before the TPS was added, when my car hit 2nd gear it would go in really hard with a thump, after the tps was added it still thumped but not as much. Whats the reason behind the hard shifts?

How can i make my transmission completely independent from my ECM?

I too had to keep my temp sensor for my temp gauge, which is supposed to trigger my fan, but im thinking of just making the fan turn on all the time because i don't want any overheating issues and the temp sensor seems to hesitate to turn on my fans sometimes.

@apeiron

The non computer controlled distributor is definetly on my buy list right now, is there any specifics that i should look for when picking one? any suggestions on one?


What other methods can i use to lock up the TCC? whats its purpose?


Lots and lots of questions guys, thanks for the replies.

 

They didn't swap in the Silverado's transmission with the engine, did they?

 

Nope i kept my camaros transmission

 

ok the 700r4 dont work off the computer... the only thing that is controlled is the torque converter lockup.. its works off the speed sensor..if you look in the tech articles for the lock up.. well heres a link https://www.thirdgen.org/torqueswitch As far as the timing goes you could get into burning your own custom chips and go that route.. but if you dont wanna mess with that you could pull out the distributor and go with an older model coil in cap design.. because if you useing the factory timing curve... it could be costing you alot of power!!!

 

Will i be running into any problems with my current transmisson setup? What exactly does that switch do? Whats the purpose of it?

Yeah since apeiron showed me that article, i think i want to go with the older style distributors, but then i still have to figure out how to time it correctly and what setting etc. I really do think my car is missing out on power at the moment.

Is there anything else that i should look into besides the switch, and distributor?

 

Don't use a switch, there's much more sophisticated ways to control the TCC besides doing it manually. https://www.thirdgen.org/forums/carb...c-control.html

You might want a thermal fan switch, too.

 

[QUOTE=Apeiron;4772331]Don't use a switch, there's much more sophisticated ways to control the TCC besides doing it manually. https://www.thirdgen.org/forums/carb...c-control.html


thats a good article

As far as the timeing goes thats something you'll just has to play with because every engine is different..

 

ive been looking at the HEI distributors on summit racing. What is the difference between these two?

I was thinking about going with this one
http://www.summitracing.com/parts/MAA-8548201C/

but im curious if i would benefit more from just getting this one, although its double the price.

http://www.summitracing.com/parts/MSD-8365/

Is it worth the extra bucks or am i ok with the first one?

 

The MSD comes with timing weights, springs, and bushing to customize the advance curve.
Is that worth the extra cash? Honestly, I don't know. I just bought the kits for OEMs never used aftermarket distributors.

 

honostly ive had VERY good performance out of the Jegs one it was like 120 bucks im almost positive it was an un baged MSD it works great unless you wanna spend the extra money id recommend it

 

Don't have to spend that much even, this would be fine http://www.summitracing.com/parts/SUM-850001R/

Assuming you can still find one there, you can take one out of a car in the junkyard and clean it up for even less.

 

this one would work fine for you... then just get a timing curve kit from them seperate..

 

Thanks for the suggestion guys I was almost going to spend 150 bucks on the dizzy alone.

@Scamaro could you point me to the proper kit? I don't want to end up buying the wrong thing.

My car is giving me horrible mpg ATM, I
Filled it up yesterday and I've driven about 20 miles and im already at half a tank.

I'm hoping the distributor helps my mpg atleast a little.

 

here ya go man hope thing helps ya out http://www.summitracing.com/parts/MOR-72300/

 

Thanks Scamaro, i should be good to go now.

you guys have been a great help.