Will the injector pod and pressure regulator from the 305 TBI unit swap directly onto a 454 TBI unit?

 

I am interested to know this myself. I dont think so, tho.

That would make the problem of fuel pressure and injector sizing too easy to solve.

 

Absolutely WILL. They are 100% drop in and bolt down.

But I don't see why you would want to complicate things with a 454 TBI on a Stock-Mild 305. The stock 305 pulls no more than about 350-400 cfm, which the stock TBI can easily supply.

 

Wait, so if you were to throw on some heads, and maybe an intake manifold, and you wanted to put on that TB because it has bigger bores, you could use your stock injectors and everything?

I bet that thing has some sexy throttle response.

 

yep, just like Fast355 already posted... but even with those mods, the SBC tb can still feed it, once modded with ultimate tbi mods.. the TB is not the bottleneck.. its flows alot.. but say you did want to put the BBC tb and injectors and regulator off a SBC on it... it would still drive like PURE CRAP! without tuning the PCM for adjustments! so much air will enter the intake at the same throttle postion VS the SBC unit, the engine will lean out, and possible backfire and pop.. its not just a bolt on, cause you have to wire the IAC and TPS sensors as well.. well TUNING..

also with that much airflow, it would be a good time to up your fuel psi, and recalabrate AFR with the tuning..

 

Thanks for the replies guys. I am not running a bone stock 305, but a 350. I've been using a stock throttle body that was bored out by Arizona Speed and Marine back when I did the engine swap. I was led to believe it was punched out to 52mm, but that doesn't appear to be the case. The car behaves like its just not getting enough air and fuel on the top end. I've got an aftermarket ECM that I intend to switch to so that tuning will only involve a laptop, and not chip burning, but that's another story. I had seen some of these 454 throttle bodies available, and was just wondering how compatible they are with the other mecahnical pieces.

Thanks again.

 

I've got a 1992 350 bored 30 over, nice cam, upgraded valve springs on truck heads , headers and edelbrock EFI system MPI.(multi-port injection/ batch fire setup) The chip in the cpu is for off road use. I have the stock TBI minus the injecters on top. Will my setup binift from a big block TBI unit? What kind of up grades can I do to my current system? Thank you for your time and consideration.

 

Easiest method is to data log a WOT blast. Then check the MAP value at RPM versus the MAP value at key-on, engine-off.

The difference is the drop though the induction system (aircleaner and throttle body). If the drop is low, under 1.5" Hg, then there isn't much of a restriction.

RBob.

 

My system is not that advanced. I have the EFI MPI with their intake and the chip in which they supplied. Which all works around the stock computer with the modified chip. Is there away to check the map sensor with a volt / om meter? If yes, what setting do I use? Thank for answering back. This board looks kind of not used much.

 

You can check it with a DVM. Measure between the MAP connector center pin and the engine block. Or between pins C11 and D2 at the ECM.

The conversion from volts to KPa is:

KPa = (Volts * 18.819) + 10.415

To convert KPa to "Hg:

"Hg = KPa * 0.29

RBob.

 

Obviously, others have had different experience here than me. In my case the injector pod was NOT a direct swap between the 305 and the 454 throttle body. I do not remember all the details.... but as I recall the front locating boss was different and even a different gasket was required as a result. I needed to use the injector pod from the 454 tbi. I do not recall if the 305 pod could be modified and used, but it was not a direct fit.

 

Injector pods from 4.3-5.7L TBI will work fine on any 454 TBI, but you must use two 4.3-5.7L injector pod gaskets. Done it many, many, many times.

 

So, I guess your saying you raise the pod high enough that the locating boss does not extend into the throttle body.

 

Yes, that is correct. The injector pods are all identical with the exception of the "locating boss". The 454 locating boss is skinnier than the SBC pods.

The locating boss on the 454 is also longer than the SBC boss. The reason for this is GM put a 1/4" spacer under the 454 injector pod and they still wanted the locating boss to sit securely in the top of the TBI.

The pictures show what i mean. The pod on the left is a SBC pod with a standard 1/8" gasket shown below. The pod on the right is a 454 pod with it's 1/4" spacer.

Hope this helps. Also, the stock non-adjustable regulator covers are identical with exception of the 454. The tab is "closed" down further on the 454 cover compared to the SBC. This is to potentially give a bit more fuel pressure.

I have pulled about a hundred 454 injector pods off and about that many SBC pods and every one of them is how i just described it.

 

They are 100% interchangeable, but you have to use a 1/4" spacer or 2 factory 1/8" injector pod gaskets.

 

i just did an engine swap in my 95 yukon (now refreshed 454) from my 1988 pickup. the newer truck has different plumbing and tps wiring, so i am running the 350 throttle body on the 454. both injectors seemed to have the same bore size, but it has emissions, economy, and idle issues (but great performance).
do i want to try to tune this setup, or do i want to try to rewire for the original 7.4litre throttle body?

 

i have a 350tbi in 94 chevy 4x4 truck i have built a 350 with vortex haeds with a
elderbrock performer intake and i made a adapter plate for the throttle body
i know it works i had the engine in a 92 two wheel drive truck and ran great
then i tried to use a 454 throttle body on it and it did not work to good
should i use the injectors from 350 or 454 and which pressure regulator 454 or 350
i bought a pigtale for iac and i have been told so many combinations none seem to
work maybe the 94 computer may work better than the 92 model