Latest progress- set minimum idle, set the IAC, and base timing

[KANE]

Yesterday was a great day!

I set the timing for 6 degrees per GM for speed-density TPI. Then I set the minimum airflow (per GM procedure) followed by the idle.

Now, GM calls for a minimum of 450-500RPM in drive for a stock TPI, but between the components (runners, chip, injectors, L82 factory cam & heads), I have her set at 600RPM. 500RPM was just too low for my set-up and she'd stumble and stall. 600RPM was the lowest she'd run comforatbly.

Then again, in my experience, 450-500 is just way too low. The previous TPI system I built was on an LM1 based 350. Same scenario though- when I tried to set the base to 500RPM it stumbled and died. Seems my combinations don't like a 500RPM minimum idle. Maybe the L98 does better at 500RPM with the more restrictive intake snorkeling and oppresive exhaust system- most likely having to do with back pressure & scavenging. It has never worked on my TPI motors. I guess it doesn't matter because they don't throw codes at an idle between 600-750RPM and they NEVER stall.

She sounds great overall. The throttle flows freely off idle and she roars through her RPM band. She really wants to run and she does well getting there. I'll have to add some octane booster when I finally get her on the street to help burn out the old gas. She really looks good with the polished intake. I really feel like the little details have made this just that much more successful in terms of the swap.

I really enjoy TPI over carbs. That may be blashemy amongst most C3 owners- but it is sooooo much easier to tune and more reliable (if done right). It cleans up the engine bay nicely. Just my $.02 though.

I'm ordering new seats this week. With any luck... she'll be on the road by the end of the month- I've still got to register her (bad owner!).
:cool

 

[silver 80]

Sounds like you should be on the road soon. I'll have to tap into your knowledge when I get as far as you are. Right now I'm just going with the stock TPI set up, from an 88 I have a complete engine, I just need to find a place that will clean the intake of all of the carbon . I am putting it on a ZZ4. I looked on the efi connection website and will most likely go with them for a harness. Have you looked into the race pumps setup?
Well it's back to the garage.
Tom

 

[KANE]

...Right now I'm just going with the stock TPI set up, from an 88 I have a complete engine, I just need to find a place that will clean the intake of all of the carbon . I am putting it on a ZZ4. I looked on the efi connection website and will most likely go with them for a harness. Have you looked into the race pumps setup?...

Sounds like your project is off to a great start too!

I was very happy with the harness I purchased from EFI connection. I would refer anyone contemplating a TPI swap to Mike Noonan. He has a stout S10 with an LT1 intake and AWD- really slick.
http://www.s10wildside.com/wildside/default.htm

I used a Painless Wiring harness on my first TPI install and wasn't happy with the length of the MAP sensor pigtail (waaaaay too short). The location of the EST bypass connector was next to the computer versus under the hood where it belongs. The power lead wiring configuration was peculiar at best. The worst part- the directions were terrible and there were NO hepful schematics.

EFI connection's harness is a perfect replica. It has the GM color coded wires and not cheap substitutions. Diagrams are simple, helpful, and to the point. The pigtails are the right length and it makes for a straight forward install. I also like the fact it comes pre-wired for fans (with relays), a fuel pump relay, and uses a heated 02 sensor (nice touch!).

As for fuel pumps, I decided to go with a high output AC Delco external pump. It is the most cost effective pump therefore costs less to replace than the expensive aftermarket pumps- this is important in the long run. I also found the best location was on the frame next to the tank and the best access to it was through the tail lights.

Good luck on your project too!

 

[silver 80]

I'm think I'm going to try the race pumps.
www.racepumps.com
I'll have to ask about the wire harness and computer, not using the ele. fuel pump.

 

[Crimson Thunder]

I'd be interested in how the Racepump works out for you and your fuel injection swap.I've been thinking about a F.I. swap and thought the Racepump would be a great alternative to running an electric pump.Please let us know how it works out.Thanks

 

[Bill75]

I'm think I'm going to try the race pumps.
www.racepumps.com
I'll have to ask about the wire harness and computer, not using the ele. fuel pump.

Racepump looks real interesting! I don't know much about FI so forgive me if this sounds stupid but don't you need the full fuel pressure at startup that an electric provides? The racepump wouldn't provide pressure until the engine was running or cranked maybe?

 

[82CorvetteGuy]

Thats cool, I just finished up my speed density TPI swap this weekend. I still need to fix some of the bugs. Right now my car is idling way to high and I can't seem to fix it, gonna play with it after work tonight. But I def like the way it looks now. :cool