Stock and hopped Z-28 engines here..

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pdq67
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Stock and hopped Z-28 engines here..

Post by pdq67 »

Just how much power did these little old engines really make?

I made a junk 301 that I figure was only like only 325 hp..So know a little bit about them.

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Re: Stock and hopped Z-28 engines here..

Post by bigmike »

Been a number of years but my mostly stock rebuilt 302 plus .030 over 68 Z/28 made about 351 HP on the dyno with no accessories, electric water pump used on dyno only and headers.
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Re: Stock and hopped Z-28 engines here..

Post by F-BIRD'88 »

There was a hot rod mag article that covered just that about the 302 Z/28 engine . Dyno tests in both restored stock oem form and also when modern hot rodded (aftermarket heads, intake, roller cam, headers) I believe the all stock motior was 350 hp and the hot rodded version was 550-560 hp.. If memory serves. Do a search. It was online.
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Re: Stock and hopped Z-28 engines here..

Post by pdq67 »

Little suckers would rock and roll, imho...

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Re: Stock and hopped Z-28 engines here..

Post by Truckedup »

Stock ones from the dealer were not all that fast, maybe mid to low 14's ...
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Re: Stock and hopped Z-28 engines here..

Post by Little Mouse »

Have an old rag that tested the 69 Z/28 against the 69 boss 302 mustang. They claimed both cars ran identical 14.98.
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Re: Stock and hopped Z-28 engines here..

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Re: Stock and hopped Z-28 engines here..

Post by vortecpro »

bigmike wrote: Sat Oct 10, 2020 11:31 am Been a number of years but my mostly stock rebuilt 302 plus .030 over 68 Z/28 made about 351 HP on the dyno with no accessories, electric water pump used on dyno only and headers.
YES
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Re: Stock and hopped Z-28 engines here..

Post by Jeff Lee »

Interesting article; roller cam, aftermarket heads, intake and carb and just about the HP output of a Stock Eliminator 302 SBC.
Have a friend building a ‘70 Boss 302 Stocker. Expecting north of 550 HP. Time will tell.
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Re: Stock and hopped Z-28 engines here..

Post by BILL-C »

A good SVRA spec vintage TRANS AM ford 302 and chevy 302 will both make 600+ HP and 420 TQ in road race trim. Iron heads (aftermarket allowed), dual plane intake, roller valvetrain, and 310 max cid. They also need to survive for hours with a brick on the gas pedal at 8 k rpm and survive the occasional 10 k rpm bad down shift.
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Re: Stock and hopped Z-28 engines here..

Post by 1980RS »

All the people except for one guy I grew up with those 302's were torque dogs. Never wasted any time on them when a well build 400 SBC could make more power for less.
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Re: Stock and hopped Z-28 engines here..

Post by Truckedup »

So how much power at the flywheel did the factory stock Z28 engine make as installed in the car on the factory assembly line?
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Re: Stock and hopped Z-28 engines here..

Post by englertracing »

1980RS wrote: Sun Oct 11, 2020 11:20 am All the people except for one guy I grew up with those 302's were torque dogs. Never wasted any time on them when a well build 400 SBC could make more power for less.
Yeah pdq has some delusion that a short stroke is an advantage....

All it does is make the port look larger compared to the displacement.
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Re: Stock and hopped Z-28 engines here..

Post by F-BIRD'88 »

Truckedup wrote: Sun Oct 11, 2020 12:07 pm So how much power at the flywheel did the factory stock Z28 engine make as installed in the car on the factory assembly line?
You can know this by finding the 1/4 mile drag test MPH and the true test weight with driver of a all stock '67-'69 Z/28 Camaro.

EG: 290 hp net as installed rated power and #3500/ #3600 weight with driver goes 101-102 MPH 1/4 mi.
Last edited by F-BIRD'88 on Sun Oct 11, 2020 1:26 pm, edited 2 times in total.
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Re: Stock and hopped Z-28 engines here..

Post by F-BIRD'88 »

1980RS wrote: Sun Oct 11, 2020 11:20 am All the people except for one guy I grew up with those 302's were torque dogs. Never wasted any time on them when a well build 400 SBC could make more power for less.
Most people will not gear their car up high enough to fully use the high rpm power band of a small cid v8 like a 302.
They won't run the long duration cam nor the high rpm induction system needed . Especially on anything that gets street duty.. The powerband is pretty much 5000+ and up (8000-8500 rpm)
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