1989 Camaro RS

[TerryD]

Check your ECM. Many tbi are not tunable, you’d have to do a chip. Later years are mem over prom, so you can use a laptop

It's a chip ECM. Moates makes an emulator that will work with it and allow me to tune on the fly but then to be permanent I would have to burn it to a prom and install it.

There is some info on getting a LS computer to run a TBI unit, but I have to do more research. Probably use a vortec timing set and cover with crankshaft pickup and a Vortec distributor. Then some kinda wizardry with assignments for the injectors or possibly a driver off a single injector. Gotta dig a bit deeper.

 

[JoshHefnerX]

If you're gonna go for power on that, you'll want to do some other kind of fuel metering.

Edit: I forgot about the Moates stuff. That dude was getting pretty old a few years ago - is he still doing those mods?

 

[TerryD]

If you're gonna go for power on that, you'll want to do some other kind of fuel metering.

Edit: I forgot about the Moates stuff. That dude was getting pretty old a few years ago - is he still doing those mods?

His store is still up so I guess?

 

[beags86]

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This is 2021. I would quit playing with all that old outdated 1990s tech and step up to some real capabilities. It will cost you more up front, but would solve all of your problems.
If was going to do a tpi engine, this is the ONLY way to fly in my opinion.

 

[TerryD]

Holley EFI 550-601 HP EFI ECU & Harness Kits

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This is 2021. I would quit playing with all that old outdated 1990s tech and step up to some real capabilities. It will cost you more up front, but would solve all of your problems.
If was going to do a tpi engine, this is the ONLY way to fly in my opinion.

Will it run TBI?

 

[Bent77]

If you're going down the rabbit hole, avoid the pigeon hole. Look for a factory TPI or MPFI setup, the Holley will for sure run those and they are far superior to any TBI things. A complete engine would have the above parts you mentioned, and should be relatively inexpensive due to the LS craze. Or LS it

 

[82355]

Did you go buy the L98? Is it a complete engine? Or were you going to run the TBI on it?

I had a friend years ago who had a 1991 RS with an LO3 and a TH700R4. He got an LO5 short block that I disassembled and cleaned up. He re-ringed it, and put it back together with a roller cam, a set of L98 heads, and a Holley TBI. He ran that combination with the factory LO3 tune. The car ran fine. Took it to Scribner back when it was still open, and it ran a 14.00x (twenty years ago, I forget the trap speed). He also had a 3.45 9 bolt rear axle from a Firebird Formula.

This is actual first hand information, not blow hard........

Martin

 

[TerryD]

Did you go buy the L98? Is it a complete engine? Or were you going to run the TBI on it?

I had a friend years ago who had a 1991 RS with an LO3 and a TH700R4. He got an LO5 short block that I disassembled and cleaned up. He re-ringed it, and put it back together with a roller cam, a set of L98 heads, and a Holley TBI. He ran that combination with the factory LO3 tune. The car ran fine. Took it to Scribner back when it was still open, and it ran a 14.00x (twenty years ago, I forget the trap speed). He also had a 3.45 9 bolt rear axle from a Firebird Formula.

This is actual first hand information, not blow hard........

Martin

I haven't gotten it yet. It's a complete engine with intake but I had planned on using my TBI on it. I don't really want to go away from the tbi. Had just planned on getting a system to tune it. I figured a Holley TBI unit or even a modded 454 TBI unit would handle 300hp pretty easily. And with a cam as mild as a L31 truck cam I didn't think it would be hard to tune in. Heck, guys in TG.O have the TBI L31 .bin they'll usually give out.

 

[Bent77]

I think my biggest reservations to that is making sure to get continued support on the software. With Eagle Mark gone and Moates stuff slowly disappearing, you could get to that point

As for the rest of the parts going on it, should work fine. I think there’s some IAC differences in the Holley vs BBC throttle bodies. You may want to look into that

 

[TerryD]

I think my biggest reservations to that is making sure to get continued support on the software. With Eagle Mark gone and Moates stuff slowly disappearing, you could get to that point

As for the rest of the parts going on it, should work fine. I think there’s some IAC differences in the Holley vs BBC throttle bodies. You may want to look into that

I've had those same thoughts. The LS computer swap on a TPI engine is extremely tempting too. But at that point, I'm changing so much of the car I might as well go with the PF4 system or even LS swap. Which is what I wanted to avoid by sticking with the factory LO3.

 

[Bent77]

Yep, you could hit $2k really fast by changing stuff. That said, even adding the other parts (just for the injection) you will likely get close to $1k. Budget may be a way to consider what your best option is

 

[TerryD]

Yep, you could hit $2k really fast by changing stuff. That said, even adding the other parts (just for the injection) you will likely get close to $1k. Budget may be a way to consider what your best option is

Yeah. Budget was where I started. Intake swap and headers and run it. Maybe a L98, L31 or LT1 cam swap in the future.

Then the whole L98 popped up. And things are trying to snowball. So I'm holding off on the L98 for now and reigning in my ambition a little for the time being.

Again, not trying to set the world on fire but a 300hp 305 in a numbers matching car is possible and not that exotic.

Just gotta be able to tune it.

 

[82355]

Just swapping the L98 long block in place of the LO3 long block would be a worthwhile upgrade.

Martin

 

[Bent77]

So lets back up a minute

Does the L98 not have the intake with it?

 

[TerryD]

So lets back up a minute

Does the L98 not have the intake with it?

It does. But again I hadn't wanted to dig into that swap. Gotta pull the fender to change the harness and on top of that I've got to actually find a harness and ECM.

 

[USSkoval]

I still vote to keep it as it is and make the best of it with the simple and cheap upgrades. It's mostly a cruiser, right?

I've daily driven a lot of third gens from carb 305's to modified TPI 350's with a manual trans. My tweaked '92 RS with LO3 and 700r4 gave me a lot of smiles per gallon and I actually miss driving that car. Was it actually fast, well of course not. But it was dead nuts reliable and felt fast.

 

[beags86]

Just gotta be able to tune it.

It seams like your major thing you keep going back is tuning it. You want to break into it? Just because? Also you keep stating you want a cruiser, but then keep on talking about how you want the extra 10 or 15, then that turns into 330hp.

Buy the L98 and swap it. With the holley setup it will be every bit as good as a LS. Without the swap cost. The L98 bolts in. And will easily spend 2k chasing the tune ability of any other system that the holley gives you from the start.
No reason why L98 tuned up really well won't push 275 in stock form. The cop car L98s were 245hp.
Then you have the ecu for a cam swap, headers, F3 procharger, or what else mods you do in the future.

 

[TerryD]

It seams like your major thing you keep going back is tuning it. You want to break into it? Just because? Also you keep stating you want a cruiser, but then keep on talking about how you want the extra 10 or 15, then that turns into 330hp.

Buy the L98 and swap it. With the holley setup it will be every bit as good as a LS. Without the swap cost. The L98 bolts in. And will easily spend 2k chasing the tune ability of any other system that the holley gives you from the start.
No reason why L98 tuned up really well won't push 275 in stock form. The cop car L98s were 245hp.
Then you have the ecu for a cam swap, headers, F3 procharger, or what else mods you do in the future.

Partly I want to try my hand at efi tuning.

The goal is a cruiser. Tweak the timing and ect just to maximize what the 305 is. Then add headers and possibly a different intake to wake it up a little more. The Hooker SMOG legal ceramic header set-up. And I was looking at the EGR Holley dual plane 4bbl intake with an adapter.

Then possibly a L31 or LT1 cam swap. Just to play with the 305. See what I can get from it.

Then in looking, the L98 popped up for a good price. Pretty easy swap and starting with bigger CID but then I'm going away from what I intended to do. So I'm rethinking that.

And everything else was just thinking via keyboard and wandering down the rabbit hole.

 

[beags86]

Fuel efficiency only makes you smile when you put pen to paper and figure it out.

Horsepower makes you smile every time you mash the pedal and drive the car.

I have no idea why anyone would bother with a 305.
All the 305 talk is irritating in itself. I can't imagine actually working on one.

 

[beags86]

You will maximize your gains with the 350.
Why stick any time into money into a 305,"just to see" only to be disappointed.
Plus if you ever sell it, the tpi 350 will be far more desirable.
I would buy a tpi, holley ecu'ed 350 camaro.
I would not bother for a second with a tbi 305, with headers,