Greetings gang,

I hesitate to dredge this topic up again, considering the beating I took from CFI-EFI in regard to using MegaSquirt for engine management but some of you may find my results interesting.

I just finished converting my 79 from carb to TPI (which I plan to do with my 84 Crossfire also). I used a TPI setup from an 85 and put it on top of a redrilled Vortec roller cam motor. The engine is de-smoged except for the stock narrow band O2, IAT and coolant sensors. I chose a MegaSquirt II Version 3.0 ECU for engine management. The MS II is controlling not only the TPI but the HEI, TCC and cooling fan.

After a bit of around town tuning I took the car out on the hiway for a 90 mile run. I maintained about 70 mph (2000) rpm during the trip and attained 25+ mpg. I am sure that I can improve on that number as I learn more about tuning the MS.

CFI-EFI was right about one thing for certain. MS is NOT for guys who want a plug & play ECM that they can plug in and roar off down the street! I had to learn some things about VE maps, ignition maps and AFR tables and I am still learning of course. I am still addressing a few tuning issues, trying to get more horse power etc. But as it stands now I am VERY happy with the overall performance AND economy of the TPI using the MS II.

If any one out there is considering MegaSquirt just drop me a line and I will help any way I can.

Take care and be safe,

Ken

 

I am glad you came back to report . Sounds like a great success. I bet tht motor looks real nice with that TPI on it also.
Let us know when the other car is done also.

 

maybe you ought to post a few pics.

 

Are all your digital gauges still working?

 

That is a beating? First, I never mentioned the MegaSquirt, as I have no personal experience with it. I guess I could have been more clear, but the comment was aimed at the expensive, time consuming, sideways move to TPI, regardless of the management system used. But even more so, the post was aimed at whomever was responsible for the sales job done on you. I was responding to THIS more than anything else.


If you are going to accuse me of giving you a "beating" (which I didn't), at least pay attention to the subject matter. It certainly wasn't the MegaSquirt.

RACE ON!!!

 

I'm glad you went ahead with the conversion, others will give there opinions on cost effectiveness vs. horsepower, time etc... but, to some people that doesn't matter. In the end you did something that a lot of people wouldn't and now you have something different that you can be very proud of and enjoy!

Your "79" must be a lot of fun to drive now with a fuel injected engine!

 

If I had a C3 with a carb, I would have kept it that way. The gas mileage cant be that much worse and its so much easier to work on. What kind of gas mileage were you getting before?

I had a '77 C10 with a 4 bbl 350 in it and man did it suck gas, but even newer trucks with a 350 dont do much better. Never had a problem with that truck, tons of torque, and very very easy to work on.

 

Way to go Ken.
Thanks for sharing that.

 

Ken,

Before you dump the Xfire, go here www.dynamicefi.com.
Much better than MS and it comes with all the software needed for scanning along with a VE Learn capability.

 

Glad you are on here posting. Obviously you have some wrenching ability. Glad it's going well. Gee, you did it without "you know who".

 

KJ', about your 84,
have you considered ditching the Crossfire manifold
but keeping TBI?

That way, you get rid of the worst part of CFI
but keep a lot of the other stuff.

 

how much was it? i am wondering because i may want to do it to my '84

 

that tpi must look pretty cool, post some pics man!

 

I converted my 84 to a multiport dual plane intake with a 4bbl throttle body. All digital guages work, the mileage is not accurate ( but never is once you change FP or injectors anyway).

Megasquirt is an amazing engine management, I have done half a dozen cars with it already.

 

Um, I'm not sure how familiar you are with megasquirt, but the dynamicefi is ancient in comparision. MS can do also do autotune, however the biggest advantage is realtime wideband closed loop.

As a tuner I can't express how critical that is. By filling out a 144 cell AFR table, and setting EGO control, you can have a very very consistant tune at all driving conditions.

 

Here is my megasquirt '84

 

Kjones, What did you do to mate the TPI ports to the vortec Ports? Did you use the SPDC vortec baseplate?

 

I'm not a "big fan" of the cfi to tpi conversion but all that matters is that you like it and are happy with it. Get some pics up so we can see it!


Silver84- Not only is the CFI intake restrictive, but the heads are restrictive as well.

 

When I read that, I thought, "That sure is different. I wonder what he used for fuel rails?". The pictures look like a single plane intake manifold. Can you elaborate on the manifold, please?

RACE ON!!!

 

I machined my own fuel rails, then sold them and picked up a set of edlebrocks, until i can machine another set.

The intake is unique due to the heads I am running, which are the fast burn vortecs. At the time there was no EFI intakes for the head from the aftermarket, so I found a mercruiser intake and machined it to work. All the injector pockets as well as the TB mounting flange needed machine work. It is actually a very large dual plane manifold.

If I had to do it over again I would just weld in bungs, like I did on this 1972 Olds 455