I am thinking of exchanging my old quadro-jet intake for a Holly high-rise. Will I see enough improvement to do this or should I stay with good old quadro? Engine is stock with stock Rochester carb., high rise would be a square port "Trantula" Holly.
Thanks,
Saulsss

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Such a manifold will pretty much trash your low end torque. If this thing is to be driven on the street, especially on a daily basis, stick with a good dual-plane manifold. Holley, Edlebrock and Weiand all make really good ones, many of which are available to reuse your Q-Jet. The Q-jet isn't a bad carb. Usually they just need a good rebuild and some fine tuning. Q-jets certainly stay in tune better than a Holley. Holleys tend to need a little more day-to-day tinkering to keep them working in top shape.

A lot hinges on your use for the vehicle. In some cases, the original manifold and carb may be your best bet and it's a lot cheaper and less hassle to rebuild that carb than to replace everything and try to get it running just right. How is this car used and driven?

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Rich's 1965 Malibu SS Restoration Project Progress Page (http://www.geocities.com/motorcity/flats/8627/)
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The car is used whenever it isn't raining or other bad weather and driven easy "most" of the time. The car runs smooth and easy just wondering how to get a little more power. Engine is starting to smoke a little so I talked with a macine shop about a rebuild and he said; $2,400.00 for total rebuild and that would be putting the 350 horse cam is it along with pulling and stuffing. He also said that the Quadro manifold is a great one and unless I was going to strat racing keep it the way it is. I also have the HEI dist. that is the only non stock part on engine. Thanks for the reply and more info..

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I think your mechanic is a pretty bright guy. Sometimes the best, most reliable, most effective parts are the ones GM put on in the first place. The HEI is an excellent and effective upgrade. If my L79 wasn't restored bone-stock I'd plop an HEI in it. I love the $25 HEI I put in my sb 400 in my truck.

By the way, my mildly modified 400 in my truck is running the original cast iron manifold and q-jet and it runs like a banshee and has not had any reliability problems at all. It is driven much like you described your Chevelle is to be driven.

Also, keep in mind that that 350hp cam will give the engine a little chop at idle and may mess with your power brakes a bit. The cam has so much overlap the engine doesn't pull much vacuum at idle so it can lessen the effects of the "power" in your power brakes at slow engine speeds. Regardless of this, the 350hp cam is one of the best SB cams out there. But I could be biased.....

The 350hp cam really comes on at higher RPMs, so a manifold and carb upgrade WOULD be a good idea to better match to the cam's capabilities. Maybe this cam isn't the best for the car's driving use. The 327/300hp cam is excellent too and better suited to lower compression motors (under 10:1). The 350hp engine uses 11:1, very large valves, heads and intake runners. The Holley carb's primaries are also much larger than the Q-jet primaries.

You've got a lot to think about! Be careful and make wise decisions and ask lots of advice. You don't want to spend a lot of $$ buying one or two hi-perf pieces that will only have a modest effect on performance. With engines, it's always important that the whole package be set up to work together. One part (manifold, cam, carb, etc.) can't make a performance engine out of a standard motor.
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Rich's 1965 Malibu SS Restoration Project Progress Page (http://www.geocities.com/motorcity/flats/8627/)
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[This message has been edited by Rich-L79 (edited 02-24-2000).]

Saul, from my tinkering as a kid you'll notice, immediately, the need for more throttle opening to get her moving, the "trashing of low end torque" referred to earlier. I went through a number of intakes and carbs because I had too much time on my hands.

Now the tarantula is not one I'm familiar with. But I ran stock GM Q, Holley Street, Holley strip and the Z/28. The best of the bunch overall was the GM Z/28 manifold which I ran a Qjet on ( also the best of the carbs I tried ) with an adpater. Didn;t like running the adapter but had to.

That's 20 some odd years ago and a mouse mill. Today, I would run a 425 HP Vette or an EDEL performer. I think a high rise dual plane will give you the combination of low speed smoothness and above 4500 rpm punch you're looking for. So in lieu of the stock GM Q mani, I would consider either of those. But stick to a dual plane with center divider. You lose low end when you go 360.

If I misunderstood and you are running a SBC, then I found the z/28 manifold tops all the way around.
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Chaas
Gold #62/ACES
67 SS396/L88



[This message has been edited by Gene Chas (edited 02-24-2000).]

So the general concensus is a dual plane high rise and keep the Qjet on running the 350HP cam? And will I need a spacer for the Qjet and if so why?
Thanks

If you get an intake that is for a square bore carb only you will need an adapter to mount a Q-jet. But Wieand and Edelbrock make intakes for Q-jets and they also have dual bolt patterns for a square bore and spreadbore carbs. I have a Wieand Action Series Plus on my big block with a Q-jet and a 406 small block with a Edelbrock Q-jet Performer RPM intake with a Q-jet and they perform great.

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69 SS 454
69 Malibu 406
ACES Member #3635

I would like to know why you think Holleys need so much attention.I installed mine 3 yrs ago haven't touched it since.It did however take time to set it up to run the way I wanted on a Performer manifold.Goes and gives 20 MPG...FRED

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thge guy is talking about a big block here...a 350HP 396 grind makes you lose low end? I don' think so.