Carbs seem to be alot easier to break in...but i got a question or two

i'm rebuilding my L98 and will be going with a pretty healthy roller cam. its a EFI motor, using HSR and stock 89 ECM. I can burn my own chips and have a fair idea of what to do. it will not idle very well using the stock chip i know, and i have no base tune for this combination. And certainly it wont drive part throttle or WOT very well.

I can "wing" it and make some changes to the bin/prom, that i hope will get it running somewhat close to being right.

I want to break it in by running it hard. I want to get initial startup going, somewhat set base timing to get it "close", let it warm up abit, get all the coolant into the motor, and maybe take it out on a short few mile trip varying rpms but not hammering on it at all. Then change oil/filter/etc, then warm it up and take it out to hammer on it a few times to set the rings. 3/4 throttle or so

Without a base tune its gonna be hard to do that. Its gonna run like crap or may not run at all. My question is can i somewhat take it easy for alittle trying to get part throttle and idle tune in order before i hammer on it? Since its not a flat tappet i wont worry about the cam break in since there is none

Or should i dump 150 bucks or so on a rough mail order tune to get me ball park?

 

I just did this on my engine today. I had a chip to start with though, but it still took all day before it broke in. It was crazy, I had 75 KPA and it was rich until the engine broke in, then it dropped to 65 KPA and was running 128/128 as I adjusted the tune. We though something was wrong at first as it needed 15 degrees initial timing and wouldnt start unless I held down the throttle. Good luck!

 

You got Frankenstein in the car??

 

Yes, its in and its running! A few little things to finish and it should be ready to drive home Monday night.

 

cool, i'm looking forward to this..... lol

i got a MAF sensor setup so maybe it wont be as finicky as SD and MAP, but its still gonna require some good tuning