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ok me and my cousin are wanting to put a 383 into a 87 camaro with 305 feul injection. will it work? i think its got a mass air flow instead of mapp.

is this a good plan?
people told us that it probly will but did anybody in here ever do this?

it puts out 420hp
we have the 383 sitting on the floor in the shop and the car sitting in the yard. so we are ready to get started.

he was thinking about a duel carb setup but i dont think thats a good idea. any suggestions?
 

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start figuring out bsfc(brake specific fuel consumtion) numbers. many peolple have injected there sbc's. you will have to make changes to the factory system.

im not a know it all. i just want renforce the fact that its possible. and may even be easier than carb setup. for people who are new to carbs.

for duals were you thinking 390's?
duals would kill street performance, a single 4 barrel is the way. you can accomplish more at that level with one 650-750 carb than with duals. now if you went Port FI , you could really maximize your 383. i cant wait to see the suggestions of others. this is something ive been thinking about doing to my caprice, even with a newer GMC TBI. i was a acura tech for a few years so im pretty good with FI.

upgrade fuel system to support 45-65 psi w/ a return.back with more..
 

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I would think the injectors may need to be upgraded to feed the engine,possiblely go with a larger MAF sensor,you will be pulling more air in.Also would probably want a bigger throttle body.I am not real sure.I have rebuilt several TPI motors,but just mild,never did anything more than that on them.Siggy,seems to know alot about these engines.Have you checked a Corvette Forum?They would probably be a good start point beig that that is where a lot of the TPI cars are.You could even look for an F-Body forum.
 

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You'll definitely want an injector change. Your also going to want to do the chip to remap the fuel and timing curves. However the more mods you make, the more nessesary it will be to again reprogram the chip. Its almost better if you have the burner and software yourself to customize. The 305 TPI's intake manifold (all stock TPI manifolds actually as they were all designed for a 305 regardless of what size engine they were on) and runners are seriously going to hamper your 383's performance. Accel, Edelbrock, TPIS etc. all make aftermarket manifolds for this. Holley makes a cool Stealthram however these only work with Speed Density (as I recently found out). They can be made to work with a MAF however the cost involved is pretty high for the retrofit.

You'll also want to keep in mind the vacuum your cam is going to produce. My TPI runs fine off about 13 inches (a bit low compared to OE specs) so there is some leeway with it.

A bigger throttle body would be nice as well although not nessesary. As you move to a bigger intake and runners, you'll want to port the plenum a bit (a very easy task) and upgrade the throttle body. I would actually reccommend staying with the TPI design and just getting the larger runners and baseplate instead of going to a Mini-ram type setup. The TPI's were torque monsters and that would compliment your 383 very well.

If your fuel system isn't already setup for this high pressure FI you'll need an intank or inline fuel pump that can supply 52+ pounds (and I'd reccomend an Adjustable Fuel Pressure Regulator so you can tinker with this). You can use an inline pump from an 85 Mustang (or Ranger) that had FI. I think they go for about 80 bucks. Walbro also makes some great aftermarket intank units that are 119 bucks or so.

Run the knock sensor if at all possible (sometimes you cant get those coolant drain plugs out of the block lol) although do not run them if you have timing gears.

If you checkout CorvetteForum.com and look under their Tech and Performance for the C4 Vettes you'll find many guys running TPI's on 383's and loving it. Many 11-12 second combos on there.

Hope I havent forgot anything and I hope this helps :).
 

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Go with the TPI setup.I began building my buds 85 T/A 7 years ago,About 1 year into it he lost a lot of money,due to court and a stint in the county correctional facility.When my money train dried up,I had to stop work on his car.He called me recentley and asked if I wanted to buy it from him.I may run out and see what he wants for it,just because I want the engine.I think he would be happier with the TPI setup.
 

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TPI's for larger displacement small blocks

Hi There.
I have been building TPI's for large displacement small blocks for about 4 years now. You can run a stockish TPI on a 383, but you will be seriously down on Horsepower above 4500 rpm. The ID of the stock runners is 1.448". That is rather small for 377, 383, 406 or 427 ci small blocks. I can and have bent my own runners out of 1.665" id Tubing, put them in the stock flanges and ported the Plenum and base manifold to match. I have even successfully opened up a stock throttle body to 55mm and made new butterflies to match. I have fit the new butterflies for a .0015 clearance.

To give you an idea of what these mods are worth, we dynoed my 406 ci small block first with a Performer RPM air gap and 750 Holley. this setup made 384 HP at 5100 rpm and 430 ft/Lbs torque at 3700. Next we installed and tuned a Stock TPI unit with 24 pph injectors to compensate for the larger displacement engine. that setup made 334 hp and 390 ft/lbs at 3100 rpm. Clearly too small for the engine. I went back to the shop and modified my system to the specs above. Then redynoed. I should mention that I was using a pretty sophisticated Computer Dyno Simulator to get the runner size and length right before I cut or bent anything. That is where the 1.66 dia and 15" long runners came from. I built the Throttle body on estimated air flow numbers from the software.

When we retested, what I got was pretty amazing to me. The engine made 434 hp at 5250 prm, which I think it pretty good, but what really impressed me was the torque. we were over 400 ft/lbs from 2600 rpm to 5200 rpm with a peak of 519 ft lbs at 4100 rpm.

I have enclosed a few pictures of the unit I just completed with these modifications done and custom powder coated of a customer. Let me also say that I personally use a Megasquirt Injection Management system to control everything. Fuel Economy went from 8 mpg with the Holley to 19 mpg with the TPI. I just added a well built 700R4 trans to the package. Now I make 434 hp, 519 ft/lbs torque and get 24 mpg on the highway thanks to the tunability of the Megasquirt.

You can have your horsepower, fuel economy, and good looks also.

anyone that would like additional information can certainly contact me.
 

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What are the specs of your 383? Heads, Cam, compression. The stock lower intake manifold's ports don't have a lot of material around them. My bowtie heads are gasket matched to fel-pro 1206 and in my opinion doesn't leave enough sealing area. Regardless of the intake and breathing problems you will need larger injectors, adjustable fuel pressure, and a custom tune.
 

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Rippin Ron

Hello Ron. I guess I was not clear enough in my last post. I dont have a 383. I have a 406 soon to be a 421. The cam specs and cam timing, I'm not prepared to discuss, but it was the same with the Performer RPM and 750 Holley and all the way through to the TPI that I am now running. Heads are nothing special. World Products Torkers 175cc intakes 68cc chambers straight plugs 2.02 1.60s. Compression is calculated at 9.78 to 1.

The base manifold is a production unit, but ported to match the 1.665 id runners. When porting, there is plenty of meat to go that far. you just hve to work a bit away from the common wall. I am down to 0.090 between the two runner passages, but as long as there is a wall between them, thats all that matters.

I did epoxy up the complete EGR passage and run gaskets without heat crossovers.

As for the injectors I did say I started with 24 pph injectors. And to ne exact, I am not running a typical adjustable fuel pressure regulator. The unit in the pictures however is not my unit. That is one with the same specs as mine, but it is one I built for a customer. As you can see, in the pictures, that unit DOES have a Holley Adjustable fuel pressure regulator. Holleys are the only ones to une in my opinion because they come with a new diaphram, and they use a thumb wheel to adjust the pressure not a bolt and jam nut. I use an aeromotive remote regulator and also 2 fuel pressure guages. 1 in the fuel rails and 1 at the regulator.

I guess I'm not sure what you are driving at when you are saying that regardless of the breathing problem I am going to need bigger injectors and adjustabe regulator and a custom tune. This unit is already running. I wouldnt need an adjustable regulator at all with the megasquirt. I could even be running at 30 psi instead of the 42 that I am running.

My unit has been running for roughly 8 months and we have been driving it in the city, on the highway and even at the track and towing w 4000 lb trailer. The unit operated flawlessly now that it is tuned in.
 

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65 Chevy Wagon said:
Hello Ron. I guess I was not clear enough in my last post. I dont have a 383. I have a 406 soon to be a 421. The cam specs and cam timing, I'm not prepared to discuss, but it was the same with the Performer RPM and 750 Holley and all the way through to the TPI that I am now running. Heads are nothing special. World Products Torkers 175cc intakes 68cc chambers straight plugs 2.02 1.60s. Compression is calculated at 9.78 to 1.

The base manifold is a production unit, but ported to match the 1.665 id runners. When porting, there is plenty of meat to go that far. you just hve to work a bit away from the common wall. I am down to 0.090 between the two runner passages, but as long as there is a wall between them, thats all that matters.

I did epoxy up the complete EGR passage and run gaskets without heat crossovers.

As for the injectors I did say I started with 24 pph injectors. And to ne exact, I am not running a typical adjustable fuel pressure regulator. The unit in the pictures however is not my unit. That is one with the same specs as mine, but it is one I built for a customer. As you can see, in the pictures, that unit DOES have a Holley Adjustable fuel pressure regulator. Holleys are the only ones to une in my opinion because they come with a new diaphram, and they use a thumb wheel to adjust the pressure not a bolt and jam nut. I use an aeromotive remote regulator and also 2 fuel pressure guages. 1 in the fuel rails and 1 at the regulator.

I guess I'm not sure what you are driving at when you are saying that regardless of the breathing problem I am going to need bigger injectors and adjustabe regulator and a custom tune. This unit is already running. I wouldnt need an adjustable regulator at all with the megasquirt. I could even be running at 30 psi instead of the 42 that I am running.

My unit has been running for roughly 8 months and we have been driving it in the city, on the highway and even at the track and towing w 4000 lb trailer. The unit operated flawlessly now that it is tuned in.
Actually the question was for the guy who started the post who wants to use his 383 with a tpi setup.
 
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