To replace? Or not to replace my cam?

[AlexTJ]

On your desktop dyno, you show single plane for the manifold type. Shouldn't it be TPI?

Actually shouldn't we set it to sequential injection instead of TPI?

[SilverXJ]

Whats the real difference between TPI and sequential? I wonder how Desktop Dyno interprets those differences because when you switch it from TPI it takes a huge torque hit.

[4.whoa]

Tpi or tbi? Tuned Port Injection like the late 80's camaros had the "tuned" runners for tq-iirc. Throttle Body Injection is just the injectors in the throttle body- not much if any runner difference so shouldn't be much power difference.

[SilverXJ]

TPI. Would our intakes (maybe just the 99+) be considered TPI?

[AlexTJ]

TPI. Would our intakes (maybe just the 99+) be considered TPI?

I always thought that TPIs were batch fire

[SilverXJ]

I always thought that TPIs were batch fire

I don't know. I thought sequential improved low end torque a bit. I think the main point being if our manifolds are tuned or not. I don't know that much about Chevys. Ask me about Jaguar engines or how to screw up a stroker.

[Cheromaniac]

TPI. Would our intakes (maybe just the 99+) be considered TPI?

All factory 4.0 intakes are considered TPI (tuned port injection).