383 TBI buildup, lots of pics!

[chromechevy]

wow, this is agreat set up, you are gonna LOVE the Torque .This thing would make my truck a total BEAST LOL. once this thing is tuned in, i assume you are gonna have a custom chip or tuning ??if you dyno this thing let us see!

[ImpalaGuy]

Originally Posted by chromechevy

wow, this is agreat set up, you are gonna LOVE the Torque .This thing would make my truck a total BEAST LOL. once this thing is tuned in, i assume you are gonna have a custom chip or tuning ??if you dyno this thing let us see!

I'm either going to program it myself or get Brian at TBI Chips to do it. It all depends on how much time vs how much money I have. I have the programming tools, but it can take a lot of iterations to get it right. I'm sure Brian could get it close a lot faster than me.

Right now the engine is almost ready to drop in. Here's what I've got to do:

1. Remove the LH valve cover and drill a breather hole.
2. Figure out how the plump the coolant/vac lines off the Edelbrock intake. The PITA is getting the fittings; it always seems to take 3 trips to the store to get the right ones.
3. Buy the torque convertor. I'm going for the Yank Truck Thruster 2600. It's $425 w/shipping. This $$$ is really what's holding me up.

[bigred2004]

Where did you order your injectors from? I want to do this same build myself. Im gathering all the parts right now for the build, where and how much were the set of 80 lb/hr injectors? I have a 50mm tb.

[ImpalaGuy]

Originally Posted by bigred2004

Where did you order your injectors from? I want to do this same build myself. Im gathering all the parts right now for the build, where and how much were the set of 80 lb/hr injectors? I have a 50mm tb.

I found my 80lb injectors on ebay. They're GM P/N 1708430. I feel like I stole them for just $60 shipped. Of course I'll feel differently if they don't work.

Other then scouting ebay the best deal I saw was from Turbo City. They sell 75lb injectors (which may be the same as mine, nobody really knows for sure) for $92x2=$184.

Which 50mm TB did you get? Mine is from Xtreme-fi. It's a GM unit that they bore out. It looks like they did a decent job, but for $220 it had better be.

[bigred2004]

Yes I have their 50mm TB too. Im trying to decided on which injectors to go with for now. The 75lb/hr injectors should do awesome with the fuel pressure adjusted right. Where did you get your vortec heads?? Were they just factory truck heads you had modified?

[RnuovZ71]

Originally Posted by ImpalaGuy

Thanks. You're right that GMPP has a TBI intake, P/N 12496821. I looked at it but decided against it for two reasons: (1) The dang thing is $400. I like GMPP stuff, but they must think it's cast out of gold for that price. I paid $170 for an Edelbrock Performer RPM plus $35 for a TBI adapter plate. (2) The ports are small. The larger ports on the Performer RPM are better for a 383. And even then I ported them out more to match the intake ports in the heads.

Ahh ok I got you now.

[MStefak]

Originally Posted by ImpalaGuy

Right now the engine is almost ready to drop in. Here's what I've got to do:

1. Remove the LH valve cover and drill a breather hole.
2. Figure out how the plump the coolant/vac lines off the Edelbrock intake. The PITA is getting the fittings; it always seems to take 3 trips to the store to get the right ones.
3. Buy the torque convertor. I'm going for the Yank Truck Thruster 2600. It's $425 w/shipping. This $$$ is really what's holding me up.

I did the same thing as you, with the intake and tbi adapter plate. I used the Performer RPM intake as well for a carb then put the Holly adapter on. As far as I remeber the thread is 3/4 for the heater core .. I used some brass pipe fittings and some solid line with a flex in it for my brake booster.

[Fast305]

The GMPP intake may seem like it has small runners, no suprise it does. What it helps does however is build torque while giving good fuel mileage. The GMPP Vortec intake also has EGR provisions. The GMPP intake is very similar in design and size to the Edelbrock Performer 3704 TBI intake. I have the 3704 on a TBI engine that is making 325+ RWHP and pull it to 6,100 rpm WOT shift points. Torque forever. It has been bored to 2" and has a BBC TBI unit on it. I am about to help a guy convert his 1994 C1500 to Vortec heads, using the GMPP conversion package. To no suprise his block has roller lifter provisions and we are using the LT4 cam in it. His dyno should look very similar to mine.

[TIM222]

I've been wondering how a engine similar to this (383) would do with a Paxton?
Pretty sure if its do-able, this is the direction I want to go.
Nice pics.

[ImpalaGuy]

Originally Posted by Fast305

The GMPP intake may seem like it has small runners, no suprise it does ...
The GMPP intake is very similar in design and size to the Edelbrock Performer 3704 TBI intake.

Yep, it's not just similar in design, it's the same design. Edelbrock makes the GMPP intake for GM. I spoke to their tech line about this last year. It's equivilant to the Performer vortec manifold, but with the TBI provisions.

I do recommend the GMPP manifold for a 305 or even a mild 350, just because it's easy to plug-and-play. But since I'm building a 383 I chose the Performer RPM manifold. Its bigger ports are better for the increased air flow demands of larger displacement engines.

Just my $0.02...

[ImpalaGuy]

Originally Posted by MStefak

I did the same thing as you, with the intake and tbi adapter plate. I used the Performer RPM intake as well for a carb then put the Holly adapter on. As far as I remeber the thread is 3/4 for the heater core .. I used some brass pipe fittings and some solid line with a flex in it for my brake booster.

Hi. Do you have any pics of your vaccuum and coolant plumbing? I'd love to see some with the air filter removed. I really don't see any big problems, but it's always nice to see what others did.

[Fast305]

Originally Posted by ImpalaGuy

Hi. Do you have any pics of your vaccuum and coolant plumbing? I'd love to see some with the air filter removed. I really don't see any big problems, but it's always nice to see what others did.

BTW, GM made the first TBI-Vortec head intake. It is used on Mexican Export trucks with the TBI Vortec 350 as well as some stock 1996 G30 vans. Edelbrock does make the GMPP piece. The factory van piece is very similar.

[tmbrguy]

Neat build, thanks for sharing. I just can't imagaine having a garage so clean. Thats truly impressive! Watch out for hood clearance, can't remember where, but someone else used that same intake set up and placed a dandy 1/2" pimple in the hood. Im using the GMPP vortec TBI manifold, for the plug and play theory. Took 3 weeks to get it

[reeder5001]

Ok ImpalaGuy it is time for an update.... inquiring minds
want to know.

[SUNNYCHIVA]

I have a simular set up. I am installing a full roller 383 stroker in my 95 tahoe, it has an edelbrock rpm air gap. What can be done about the egr, since there is now no place to mount the sensor.

[ImpalaGuy]

Originally Posted by reeder5001

Ok ImpalaGuy it is time for an update.... inquiring minds
want to know.

Yes it is time for an update. I've been waiting for my torque converter, which just came in this week! It's a Yank Truck Thruster 2600. Total cost was $465 (i.e. the main reason the project was on-hold). Here's a pic...



The motor has a few more parts on it as well. I installed the distributor, plugs and wires. It looks like the water pump I was sold won't work -- it doesn't have a connection for the heater hose. Really sucks since I decreased, primed and painted this one...



Right now I'm looking at install dates of 12/9 or 12/30. Basically depends on when my install buddies are available and how cold it will be in the garage. I also have to come up with a base tune for it.

[badassstroker]

Looks good impalaguy. I just built a 383 also. i went with brodix heads tho cuz i heard they were awesome. i also decided to go with the stealthram tpi setup. now i just have to figure out how to get it tuned. my friend has a ford lightning and thinks he is king sh*t on turd island. i gotta prove him wrong!!

[TrmBrainInjury]

I've been scouring the internet and every magazine/catalog I own researching almost the exact buildup you're doing. I'm trying to decide on what intake and injection system to go with. I have the same comp cam you've got the only difference really is I used the dart aluminum heads. I like the idea of the RPM intake, I'm just worried about emissions inspection without the EGR, I don't even know if it's required in AZ. I'm waiting for some 1 5/8" headers I ordered and an aluminum waterpump but I can't decide on an aftermarket injection set up or modifying an edelbrock multiport conversion or trying to get an upgraded TBI system to work. I really want the TBI to work so please let us know how it goes. I'm working on the same '95 platform so hopefully we can trade notes. Do you think the cam will require that converter? I'm at 9.75 compression with some JE pistons, what did you end up with?

[TrmBrainInjury]

Bad news, I called Tom at Turbo City today to buy all of the upgraded TBI stufff I would need to run this motor and he said there's no way to upgrade even a big block TB to feed this motor and cam combo. Now I'm looking at the xtreme xfi stuff and it looks like it's going to take a while to afford this set up. Has anyone tried any other systems that work well and are emissions legal kits?

[ImpalaGuy]

Originally Posted by TrmBrainInjury

Bad news, I called Tom at Turbo City today to buy all of the upgraded TBI stufff I would need to run this motor and he said there's no way to upgrade even a big block TB to feed this motor and cam combo. Now I'm looking at the xtreme xfi stuff and it looks like it's going to take a while to afford this set up. Has anyone tried any other systems that work well and are emissions legal kits?

I bought the 50mm TBI from xtreme FI as well as 80 lb/hr injectors. As you found, it's not cheap. I thought of using a vortec stealthram also, but was leary of trying to get an LT1 throttle body to work. I don't know if it would be impossible, but I'm sure it would take dozens and dozens of tunes trying, and even then it might not work. So I bailed on the stealthram idea and stuck with the TBI.

The Edelbrock MPFI isn't that great for bigger displacement motors. I tuned a friend's truck with a 383 and that system and an even smaller cam and non-ported heads. I would read vacuum at WOT with the datamaster. The intake that comes with it has ports that are too small. They're basically the same as the Performer manifold, verses the Performer RPM that I went with.

Looks like I'll be installing her around 12/30. It was freakin' 18 degrees this past Saturday!