i have a stock ZZ4 crate engine and a fine tuned TPI ($8D) calibration for it but want to build a TBI from a stock 350 TBI (VIN K) Engine on it (in fact i want to build the engine into a 89 Van and keep the factory TBI from this Van).

Of course i will have to fine tune the TBI later but first to get the engine running with a nearly appropriate cal is it possible to copy&paste the VE's from the TPIs MAP-table to the TBIs?

I'm using Tunercat and have bin-def's for both ECMs...

or, if someone has already calibrated a ZZ4 on a stock TBI could you post your cal?

 

It's possible to copy and paste anything into anything else- the question is how well or poorly it'll work. Clearly the intake runner lengths are markedly different between TPI and TBI, which will affect the fuel and spark maps. My suggestion would be to start with the factory TBI calibration and go from there.

The ZZ4 cam isn't that hard to tune around and my hunch is that you're not going to be that far off from the factory TBI calibration anyway.

 

the basic question is, does a VE value of 70 in a TPI table mean the same in a TBI table

 

NOT AT ALL....Its VERY different between them.. You can use the timing map, but I wouldn't suggest it.

I have tuned a ZZ4 Cam in a TBI headed TBI engine in my 1983 G20 Van. Get with on this project, I know alot about getting it running correctly. I would love to see your project running well as I am partial to the older G-vans.

I would drop the TPI in the van, but to each his own.

 

the TPI is already planned for an other project ;-)

ok i have to think a bit about it, but likely i will start with the factory cal of the stock 350