BBC performance intake manifolds

[F-BIRD'88]

Dumb question but have to ask. Does this engine have hydraulic roller lifters?

[Erland Cox]

No, solid roller.

Erland

[GARY C]

It would be interesting if you could find a low cost way of testing the surface temp of the intake on the track vs sitting still on a dyno, my guess is there is a lot more air moving through the engine compartment at speed than there is with just a fan.

[Erland Cox]

Probably but it is first moving through the radiator.
It is more of an on the dyno thing because the Corvette has more power than it can ever use mon the track.

Erland

[pamotorman]

if the rules allow it block the back of the hood up to allow the hot air out.

[MadBill]

That would appear to be a good move, but I've tested a number of vehicles using yarn tufts and at speed they were always sucked in through the gap. (think cowl induction)

PS, Erland: PM sent.

[gnicholson]

If its pulling cool air in from the cowl its pushing out hot air somewhere else

[cjperformance]

That would appear to be a good move, but I've tested a number of vehicles using yarn tufts and at speed they were always sucked in through the gap. (think cowl induction)

PS, Erland: PM sent.

Isn't this an eye opener! Wool and BluTac! Sure shows where the air is going and can be very surprising indeed !

[pamotorman]

leave out or cut holes in the inter fenders panels.

[CharlieB53]

Why are we reluctant to paint alum intakes with flat or satin black to radiate heat out rather than polish which tends to retain heat?

Lifter cover plates can and will lessen oil splash from the bottom of the intake but wouldn't it be wise to fabricate another polished reflective protector plate that could bolt to studs welded on the bottom of the intake?

Sometimes I think too much.

[MadBill]

This was discussed on pages 1. & 2...

[pdq67]

Just how good is a port-matched, Holley oval port, "Strip Dominator", intake on a 427/454/496?

Compared to say oval port, "Team G", and a, "Victor", type?

I have read that some considered a, "Strip Dom", as an under-rated intake.

pdq67

[F-BIRD'88]

The Holley Big Block chev oval port strip dominator intake manifold is a very very good racing single plane intake. It is also a great baseline start point for those who like to carve and create with a die grinder and tig welder.
We did one with a carb adapter and a Holley dominator carb on a serious 468CID oval port BBC.
it make serious serious power and ran great.
Likes to be used on a power capable motor. it likes to eat.

This is a good intake I would use with my dual Qjet carbs ("six shooter") carbs on a adapter scheme
if on a street strip bracket racer Big block chevy. Its a great start point for this and many other powerful BBC oval port combos. Some people even stick them on Rectangle port engines.

[MadBill]

One of David Vizard's books (I thought it was the Holley one, but no...) details his extensive work to reduce manifold temperature on an SBF. He used spray foam on the underside with an aluminum shield, divorced the water manifold, used heat-rejecting paint, etc. I'll try to find the reference, but AIR, he picked up ~ 20 HP..

Found it, in DV's 2010 edition of How to Build Horsepower. Unfortunately, he did some manifold porting at the same time, so the 30 lb-ft. and 40 HP gain on a 5.0 SBF doesn't relate.

[MadBill]

A couple of thoughts on manifolds, an engine sidebar and some pulse-raising Corvette (mostly) Vintage racing:
o The long restrictive runners of a dual plane, even with the divider trimmed, trade off mid and top end power in favour of lower RPM grunt, say <4000 in this case. The last thing a stout Road Race BB with skinny tires needs is more grunt!
o What it does need is air and again, even with the divider removed, the dual plane with an 850 CFM carb will tend to choke off the top end.
o If you stick with the trimmed dual plane Erland, are you familiar with the factory L88 stagger jetting and fuel distribution tabs for same?
o A Chev recommendation for the ZL-1 heads that I haven't seen mentioned lately is to use projected tip plugs in 4 cylinders and retracted ones in the others, to compensate for the good/bad cylinder flow variations. (can't recall which go where at the moment...)
o https://www.youtube.com/watch?v=tH8B1qGbeu0