Re: Crossfire mod.. plenum volume or enlarged TBIs first?

["Kevin Reynolds" <kereyn@gte.net>]

The 747 is in, but haven't done any of the other mods. I'm kinda waiting to
do the EGR tunnel etc when I pull the intake to replace the stock heads and
upgrade the cam. Lack of $$$ right now is holding that off.

Still using the stock Vette injectors which as far as I can find are about
10lb larger than the stock 5.7 truck ones give or take due to the front rear
stock variation. It may be true because I had the fuel pressure at 14.5psi
to compensate for a lean condition in non-feedback sections with the 84
Vette ECM/prom and mentioned engine mods. With the 7747 running a 1990 5.7
chip it was overly rich in cold start and is running 108 BLMs. Will re
adjust back to the original 11-12psi range and see what happens.
I will be going to matched injectors etc, but since the power out put will
(hopefully)
be quite different with the cam/head change I don't want to buy 55lb
injectors then have to replace them with 80 to 90lbers.
With the stock heads and current cam I doubt it's capable of more than
250-260hp. The stock injectors should be capable of that, but I feel the
engine needs more CFM than it is getting and is this cause of the lack of
higher RPM oomph. Since my setup is fairly mild and I'm pulling around 34-35
kpa at idle, my idle quality isn't a problem, I feel I canhold off on the
re-plumbing the fuel stuff until the larger injectors are needed. I'm just
wondering which would be a better way to cure my problem. larger butterflies
or Spacer for volume?
Of course the reason I'm here is to find answers, not because I have them,
so fire away.

Kevin R

> Your now running the 747?.
> What injectors?.
> Ya, replumb the fuel pressure reg.s?.
>
> You need to have the fuel up to snuff first.
> If you overdo the air first then you can go lean, and start buying parts.
>
> Did you cut the EGR tunnel out, and runner roofs back?.
> Grumpy
>
>



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