82 CFI - Crate Motor?

Howard Barker

New Member
So I have had the car for 15 years and its coming out of paint shop soon after a minor (minor? on a vette? did I just say that?) accident.

I originally bought the car because I liked C3's and I planned on driving it often so FI, 4 speed auto and MPG were a consideration for me. Besides I couldn't afford a chrome bumper car. But now it just too slow for me to enjoy.

I have considered every option from X-ram(yes, it's been that long) to carb conversion to Renegade to LS style FI engine. I have read many threads on various other sites and a lot of the ones here until my eyes started to ring and my ears started tearing up . . . I think . . .

What I learned was that although the CFI system works OK for what it is, its just isn't ever going to be anywhere near the equal of the later EFI systems.Having said that, I just don't want to modify the car that drastically from the way it was built. So I'm looking to keep it CFI. Don't get me wrong, I don't have any misconceptions about an "82" drastically escalating in value but only in original factory form. And, as previously mentioned, I realize I'm dealing with a "limited" (understatement of the year?) system. But I just think if I was going to make such drastic changes in the name of performance, I should just get an 80 or even a 79 and start with new bumpers. But . . . I have an 82, I made my own bed and I'll have to sleep in it. Or toss and turn for another 15 years.

What I already really knew, but was certainly reinforced especially here, is that the project as a whole has to be considered and all modifications have to perform in concert in order to be most effective.
So, that brings me to my list of particular goals. I still want to drive the car almost daily. I live in a city where its hot all year, with lots of traffic. We don't survive without A/C down here so it has to idle in traffic and I'd like to be able to put it in gear without having to hold the brake pedal with both feet and still have my head snap back when it hits drive. I need to get gas from an ordinary gas station so 91 or 92 octane is about all I can usually expect. Obviously I don't need it pinging or detonating
.
How much horse power and torque do I want? All I can get with the above conditions and the dreaded CFI.

Of all the Renegade threads I have read, most discuss which cam/head combination to use and so on. Some talk about 383 stroker upgrade also. But I haven't found (or I missed it) exactly what info I'm looking for.
Given all the limitations I listed above, I don't want to be limited by CI. I don't want to be limited by heads or cam. But I also don't want to get stuck with a really nice long block set up the my CFI with a Renegade won't compliment.

So here's my question: Lets assume I start with an 82, no engine, and a brand new Renegade, what would be my best choice given my list of needs.
Here are a couple that I have looked at. Looking at some of the head and cam specs listed on this site some of these may be a good fit but again, I know the package has to be considered as a whole.

http://www.blueprintengines.com/ind...anding/gm-383-main/item/gm-383-base-bp3834ct1

http://www.blueprintengines.com/ind...landing/gm-396-main/item/gm-396-base-bp3961ct

http://www.blueprintengines.com/ind...anding/gm-400-main/item/gm-400-base-bp4001ct1

http://www.blueprintengines.com/ind...ding/gm-427-main/item/chevy-427-base-ps4271ct

http://garage.grumpysperformance.com/index.php?threads/refresh-1982-crossfire-vette.14173/

Probably not a serious consideration but I just couldn't resist!

I guess my main concern is "will my CFI that is upgraded with a Renegade, different injectors and maybe an ECM ever be able to feed 383 or bigger CI with the higher lift cams?" And "will these high horse crate motors ever idle smooth with an auto and be suitable for more than occasional city use?"

I do like the idea of a crate motor as opposed to building one. Two reasons, I can install myself. And gun to my head, I could probably rebuild it myself, but more than likely I would die of old age (I'm already old) before I finished. Also I like the idea of a warranty for a couple of years which I won't get if I find a local builder and get one to my specs.

I should also add, that the car is already equipped with 2" stainless dual exhaust (cat free) and a 355 gear ratio diff. It is in need of a trans overhaul so that can be upgraded as necessary when engine goes in.

And now to address the 900 pound elephant in the room:
I didn't put a horse power goal in my post for a reason. HP is very important to me. But I expect that with a CFI (even upgraded) it would be significantly less than stated claims from the manufacturer. So I would like to know what to expect, but I trying to keep my expectations realistic.

I appreciate the forum and thanks for any advice you may have.
 
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Welcome Howard. You have found the right place. I'm almost certain that Grumpy has already done what you are planning
and Brian surely can give very good advice also.
 
Welcome to the forum Howard! This one is definitely one for Grumpy to help with, I would just get in the way at this point.
 
You want to build Your C3 Corvette Crossfire exact as Drawman 44 did with his Corvette.
Without ability to tune making power upgrades is all for nothing .

Other option is drop in a Big Block Chevy.
Trans and Diff will need to be upgraded rebuilt.
I rebuild the 1980-82 C3 Dana 44 aluminium rear diffs.
 
ANY of the engines listed and especially the roller cammed engines would REQUIRE a 2800 rpm to 3000 rpm stall speed converter be used , to have an engine with a cam like those listed perform well, in a daily driver.
DURABILITY and TROUBLE FREE opperation requires you to think things through carefully and match the components to the intended operational power range, factors like engine and transmission,cooling and fuel supply issues, and matching the converter stall rpm to the engines power band, are easily over looked but will cause you problems if you do so.
Its really no fun having a car you can,t jump into and drive nearly any place you choose to so try hard to match parts and Id strongly suggest than on a street car , parts selection, always starts with you considering durability , and ease of operation in that street driveable friendly, 2500rpm-5500rpm power band more than peak power as the prime goal!
that 3.55:1 rear gear is a good match, the dual throttle body injection on the renegade intake , once upgraded to provide more fuel flow should not be a problem.
but of the options you listed I like this choice, (the 396) the use of the cfi and renegade intake will tend to lower the upper operational rpm range but it may ( and probably will) slightly increase the mid rpm torque, youll NEED to have the two throttle body injectors flow rates increased to run ANY of the engines because the stock throttle body injectors were designed for about 260 hp , not nearly double that power level.
if you were building a TPI version with 8 injectors you would want 40 lb injectors, 40x8=320 lb
320 lb/2 for similar throttle body flow-160 lb injectors
http://www.witchhunter.com/injectorcalc1.php

your stock fuel pump will need to be upgraded and the fuel pressure regulator set up to provide the required pressure for what ever throttle bodies you install .
you can certainly do what you want to accomplish and have a rather impressive car with brisk performance, but the cars fuel system and converter will need to be upgraded and a 2" exhaust will further limit the upper rpm range potential.

http://www.blueprintengines.com/ind...landing/gm-396-main/item/gm-396-base-bp3961ct

CRATE ENGINES

http://www.jegs.com/c/Engines-Components_Engine-Assembled-Ready-to-Run/10763/10002/-1

http://www.tristarengines.com/catalog/high-performance-crate-engines/gm/383.html

https://www.summitracing.com/search/part-type/crate-engines

http://www.shafiroff.com/

http://www.tristarengines.com/catal...-engine.html?gclid=CIiE06P8j9MCFYaIswodlq8Ewg

http://www.chevrolet.com/performance/crate-engines

http://www.speedwaymotors.com/shop/crate-engines~6-10-344

http://rehermorrison.com/

http://www.herbertcams.com/herbert-cams-crate-engines/

http://www.proformanceunlimited.com/home3.html

http://www.jasperengines.com/crate-engines

http://blueprintengines.com/index.php/products/bp-gm-crate-engines-landing

http://www.gmperformancemotor.com/category/ENG.html

http://www.throttlebodyinjection.com/?gclid=CKbS0-Xfz80CFdBZhgod0pcNJg

http://garage.grumpysperformance.com/index.php?threads/setting-up-your-fuel-system.211/

http://garage.grumpysperformance.com/index.php?threads/calculate-fuel-injector-size.1200/

http://garage.grumpysperformance.com/index.php?threads/how-big-a-fuel-pump-do-you-need.1939/
 
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WOW! That was Fast!

Thanks for the feedback and advice.

Correction to my original post: My current dual exhaust is actually 2.5 inches.

I was aware that I would need a higher stall converter but didn't know what speed or how to calculate.

I had also planned to change the pump to an 85 Corvette pump but there also seems to be several of aftermarket choices that also fit into the factory sender as well.

As for the injectors, I knew they wouldn't be sufficient but I was worried that whatever I needed would not exist. Based on this info
320 lb/2 for similar throttle body flow-160 lb injectors
,
I found these injectors available. So now my questions are will they fit into stock TB's? Do the stock TB's have to be modified? And lets assume for a moment that 160lb is to much, Isn't the actual fuel amount determined by the ECM? So then as long as the injector is capable of needed fuel delivery, it can be governed by the ECM to deliver exactly what's programed. Am I correct here?
https://www.holley.com/products/fuel_systems/fuel_injection/injectors/parts/522-161

And as far as the ECM,
Without ability to tune making power upgrades is all for nothing .
I get this. I don't have any solution as yet but I have read that this one (PN 01228746) can work in a modified CFI and can be reprogrammed as necessary. Would that be my best choice? It seems there are other choices for later model GM ECM's that have been used but I haven't been able to find a definitive answer as yet.

Again Grump, Thank you very much for your input here,
but of the options you listed I like this choice, (the 396)
I agree that it is a great choice for me. Problem is I don't understand why? When I am looking at these different specs, I am really just seeing numbers. I can understand the numbers but I am limited in my ability to put those numbers together with the other specs of the car to come up with the right choice.
What was it about the 396 that made you think it was best for the rest of my application? The reason I ask is so that in my further research, I'll know better what to look for and what to watch out for. I am not married to purchasing from BluePrint though. I just posted those because they seem to have a lot of choices. I do like being able to purchase from a major company like Jegs or Summit in case I have a problem but I will look further to make sure I don't over look a better choice before I pull the trigger.

Thanks to all.
 
I am friends with Drawman 44. He hasn't been here on Grumpys in a while.
He has a couple of threads here detailed on his C3 Crossfire engine build.
I believe it was EBL that he used for ECM tuning.
The stock ECM would be lucky to cover an additional 20-30 Hp gains as is.
 
I did pretty close the same as drawmain's build.
I also have a copy of Drawmains early bin (for EBL Flash ECM) file from fall of last year, my car fired right up and idled smooth with it!

Your engine is pretty much the same thing as mine, except I have the cold air intake (I have an 84).

My build got a bit messy due to a tv cable and my 700r4, for my year there is a special tv cable, after market ones apparently don't fit well on the throttle body.
Brian saved helped my butt there :)

My car now behaves totally different, it has real power and an actual power band now, where it use to fall flat on it's face it now takes off like a rocket.
 
Gribbles, I'm glad the old bin worked to get you started :)

Howard, do you have a source to get larger diameter TB's? For a 383 you are going to need at least a 2" bore, and for the larger motors 2.25". The Renegade will handle up to 2.25". If you get your existing TB's bored MAKE SURE they retain the balance ports, otherwise balancing the TB's is going to be almost impossible. If you find some online, same thing, make sure the balance ports are there and working.

You can get 90 lb injectors from Rockauto.com that will fit your CFI, the holley injectors you referenced above are for TPI applications. You will need to modify your fuel pressure regulator on the driver's side TB to allow you to increase your fuel pressure. On a 383, with two 90 lb injectors, you will need 20psi to support 422 hp. 15 psi will support around 365 hp. I got a vacuum referenced regulator from eBay that will allow 20 psi for 100 bucks. Some guys run even higher pressures. (Those figures work for the larger engines you linked, as well) As far as ECM, go with the EBL Flash, its a great programmable ECM with lots of online support. You will need to swap the ends of your harness to the later type (82's have a card edge, the new one is pins) but that isn't hard and the EBL is easy to tune with. All you need is a laptop, and time and patience. A wide band O2 is recommended, but not required ( I haven't gotten one yet). If you haven't yet, check out my thread here: http://garage.grumpysperformance.com/index.php?threads/head-and-cam-swap-82-cfi.10412/

Making the CFI better isn't impossible, it just takes time. Get the Renegade and the EBL Flash, then go for the big motor. Like I said though, for 383 and up, you will need bored TB's
 
http://garage.grumpysperformance.com/index.php?threads/1982-vette-idle-issues.10822/#post-47363

http://garage.grumpysperformance.com/index.php?threads/the-cross-ram-intake.623/#post-834

http://garage.grumpysperformance.co...sfire-vette-won-t-run-right.10096/#post-39710

http://garage.grumpysperformance.com/index.php?threads/got-a-cross-fire-corvette.640/#post-25767

you can easily fabricate a custom built MANOMETER (fancy word for a tool that allows you to balanceand equalize the flow rates of the two throttle bodys on the cross fire intake manifold
STEP ONE



Shopping



Hit the local hardware store and buy 12 feet or so of 5/16” or 3/8” clear vinyl tubing. There are some photos circulating the web of a home made manometerusing very thin tubing . like maybe 1/8”. If you are considering this, slap yourself or poke yourself in the eye with a sharp stick . . because that will be less painful that trying to get the bubbles out of 1/8” tubing.



Get some nylon clips to hold the tubing . . . if you are an actual genuine red-neck, you may use strips of duct tape or bent over rusty nails. For a classy read-neckmanometer, splurge and get a get a $1 yardstick. Here again black marks every inch is all you really need, but the yardstick is in the budget, so go ahead, get crazy.

You need two one inch long pieces of vacuum hose . . you can buy new or snip some from your vacuum gage or from under your hood somewhere.

Some food coloring is nice, but not required. BTW, the term ‘food’ actually means “food, clothing, hands, garage floor, car body, dog and anything else nearby” coloring.

Now the tricky part is finding special ‘manometer wood’. This is rare stuff not usually available at any store. Fortunately it can often be found propped up in the corner of the average garage, origin unknown, age unknown. It comes in various sizes and is easily recognized by the brown color.

Shopping expedition should yield a bootay pile similar to this:

mano1.jpg

STEP TWO



Build the manometer. (i.e. arrange the bootay like so:)

mano2.jpg

STEP THREE



Stick the vacuum tubing into the ends of the vinyl

mano3.jpg



Hardly deserves its own step . . . OK, we’ll do the hanger too:



In keeping with the overall red-neck theme .. concoct some form of hanger. Here we see the recycled peg board hanger method.
mano4.jpg


OPTIONAL STEP



Your water manometer is exactly as accurate as anything you can buy. It is also very . . . responsive, shall we say. If you hook your manometer up to the port when it is pulling a lot of vacuum, you have .001 seconds to disconnect it before the water goes bye-bye. Don’t worry about it if it happens, It will not hurt the engine at all.



You can install restrictors in the line to dampen the response of the manometer without changing the accuracy. Any small orifice will do and it actually only has to be in one leg. I used a piece of aluminum rod with a 1/16” hole drilled thru it. I later discovered that a very small plastic wall anchor stuck into one of the pieces of vacuum tubing works almost as well.

mano5.jpg

And Viola! (that’s French for Gosh Dern!) You now have a working manometer!




STEP FOUR



Just add water.



You can mix up some food coloring in a bowl . . dip one end ogf the manometer tube in the water and suck on the other end until you get about half themanometer’s height in water sucked in. Remove the end from the bowl and hold both ends up high and the manometer will fill up nicely . . .



Perform a quality control test of the hanger mechanism:
mano6.jpg


mano7.jpg

mano8.jpg

mano9.jpg

mano10.jpg

mano11.jpg

STEP FIVE
 
That's exactly right, Grumpy, and I have one of those homemade manometers hanging up in my garage, but when you bore out the TB's on the CFI, it renders the middle port that we use to balance the TB's unusable unless the machinist sleeves the bore and re-drills the port. I don't know of anyone besides DCS that is doing that, and DCS is currently out of business.
 
Bob has hand machined Stainless steel skeeves for me on a Gallop lathe.
.008" thick wall.

Boring out a Pre existing hole in a part is tricky with a Verticle Mill like a Bridgeport Mill.
Even with A Standard Kurt Vise the Knee & Column table setup is not super rigid.
Prone to chattering during cuts.
One off CNC Machine operations none are interested.
No Money to be made $.
Fixture Jigs must be made or changed from regular production work.
And it must be programned.
One error and your part is Junk.

Best done on a Hornizontal Boring machine.
About 10 tons of precision cast iron cast machined & hand scraped ways.
Maintain + - .0001" tolerance eoth a skilled operator like Bob.
When we made Matts one off C3 Billet Aluminium Diff Cover most of it was on a completed on Bobs Work Horizontal Boring machine.

The inside was roughed out on a 5-axis CNC Mazak .
The Shop Foreman programmed himself.
Inside job completed just for me.
Because I worked there prior.
 
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