forgive me but i dont see / cant find any threads on gen 1 sbc into these gen 3s. I have a newly built 300 hp carburated gen 1 350 and am considering swappin it into my 92 305 z28. thoughts???

 

The 92 Z has a gen1 sbc. However, it is updated for better rear main, pan an valve cover gaskets along with a roller cam.

Is your Z a tbi car or tpi car now? If it's a tpi, I'd do a correct 350 with roller cam and something like a stealth or mini ram.

 

As noted, it came as original equipment is most models.
The 350 should be a 90% drop in replacement for your 305 Engine mounts, headers, oil pans and most of the accessories will swap over.
Converting from EFI to carb is a different matter.

 

It's a tuned port injection car. So you guys are telling me that this engine is just a plain old small block Chevy block anyways. So my rebuilt engine with a carburetor on it would fit in this car and everything would bolt up and I could use the tuned port injection with that engine

 

Engine for engine, yes, the 92 is a plain old SBC albeit, as TTOP pointed, somewhat improved in it's architecture.
What year is your 350?
What year are the heads?
Both important to know.
There'll be crossover from 2 pc rear main seal to a 1 piece version so the oil pans are different.
Manifold bolt alignment is another matter. Older engines have all of the manifold bolts at 90 degrees to the head. Later models have the centre 4 bolts at a different angle.
There are workarounds but it depends on a few other details.

 

As already brought up...

1987 through 1995 Model Year Heads require an Intake-Manifold specific to those Heads.
So Earlier Heads and Later Heads will not fit a 1992 TPI Intake Manifold.

 

I've no experience with the post 87 versions but I am aware that there's a workaround to get one to adapt to the other.
Any insight into that?

 

Yes.
The difference is only in the Angle that the Intake-Manifold Bolts go into the Cylinder-Heads.
Many people have been successful mating the 1987 - 1995 Intake-Manifolds to Older/ Newer Heads by elongating the Bolt-Holes in the Intake-Manifold.
The same could be done with 1987 - 1995 Heads with an Older/ Newer Intake-Manifold (elongate the Bolt-Holes in the Intake-Manifold).

Note: Any Flat-Milling or Angle-Milling of the Cylinder-Heads, could further complicate a Mix-Match of these Parts.

Note-2: This does not really work out with the 1996 and Up Vortec Parts... I don't recommend mixing them with 1987 - 1995 Parts.

 

I mentioned I haven't direct experience but I had heard of these.



https://www.summitracing.com/parts/pfs-52112



As for Vortecs, that's been my platform since I got back into the game twenty years back. Bought them new from the General in 2001.
My current heads are the RHS Pro Torker Vortec. Upgrades of the OEM version. Interestingly, they're drilled for a Vortec pattern as well as the early Gen 1 pattern.
Something I haven't done is verify port alignment with a Gen 1 intake. I understand it can be problematic.
Currently looking for a Vic Jr intake (or equivalent) for the Vortec pattern.

 

I did some substantial Engine-Dynomometer Testing of 350", 383", and 400" Engines with OEM Vortec Heads (and GMPP "Fast-Burn" Heads).
I found the Vortec Victor Jr. Intake-Manifold to lose HP and Torque in almost all Engine Combinations, compared to the Vortec Performer-RPM Air-Gap.
Please feel free to PM me with your Engine Specs... I will let you know which Intake-Manifold would produce which results; and you can pick one.

BTW, a slightly modified and ported Vortec Performer-RPM Air-Gap Intake-Manifold beat out the Victor Manifold in all but one Test for Peak-HP.

 

I'll look tomorrow to see what I have. I know it has a spread bore air gap intake. Aluminum heads.

 

What is the part number on this? I will do some searching.

 

Just to make a correction on my behalf... The Edelbrock Intake Manifolds are Vortec Super Victor Manifolds.
There never have been Vortec Victor Jr. Manifolds.

The Edelbrock Part Number for this Intake Manifold is #2913.

Not to be confused with Edelbrock Part Number #2814... which only fits GMPP Bowtie Vortec Heads (NOT production Vortec Heads).

 

I think Mr Vortec beat you to it. All good though.
It's one of those areas I'd like to experiment with even though I'm aware how versatile the two plane Air Gap is.

 

That information isn't lost on me. From most accounts, the Air Gap gets the job done.
Still, there a those that say if north of 6500 is a target, then maybe a single plane may be the way to go.
But...
That is interesting.
I've read and watched the Performer intakes stepping up their potential with a carb spacer but haven't seen anything (verifiable) with a spacer on top of the RPM Air Gap. That too is something I'd like to experiment with when I'm back at the track.

 

An Engine with a higher RPM operating range/ higher power band, can definitely benefit from a Victor Jr. or Super Victor.
Also there are single-plane Intake Manifolds that are intended for lower RPM use... and can increase peak HP.

When comparing a Dual vs a Single Plane Manifold...
If the Engine makes peak HP at 6,500 RPM...
and the Single Plain Manifold produces less HP below 7,000 RPM...
Well there is no point in using the Single Plane for that application.

The Vortec Performer RPM Air-Gap Manifold, and the Super Victor Manifold produce results of a similar nature.
Also by removing the Dual-Plane Divider (increasing Plenum Volume), adding a 1" Spacer, preferably a HVH Spacer (increasing Plenum Volume), and some minor porting...
The Vortec Performer RPM Air-Gap Manifold can beat out the Super Victor Manifold, in Peak HP (below 7,500 RPM), while retaining the higher Average HP of the Dual-Plane design.
Not to mention, keeping the higher Average and Peak Torque of the Dual-Plane design (not as important with 400+ Inches... but i would never actually use these Heads for an Engine that size).

 

The last of the Production Small Block Chevrolet Engines were done nicely!
GM actually tried to "go out with a bang" for the 5700 Vortec (L31 350 R-Engine) Project.


I wish that they were just as successful with the last of the Production Big Block Chevrolet Engines...
The Gen-VI 8100 Vortec (L18 496) Engine was crap compared to the 5700 Vortec Engine.

Sadly GM actually invested a good amount of money in the Project...
They created a larger Iron version of the LS1 Cylinder-Heads.
The idea was good on paper, but did not workout so well in reality.
GM should have just started with a previous Aluminum Oval-Port (NOT the "Peanut-Port" Design) Cylinder-Head...
and make small changes for Emissions and Fuel Economy.

O well!
Thanks to modern Turbocharger Technology being massively better than anything from 20 to 30 Years ago...
and the fact that all Turbo Tech other than the "Cutting-Edge" is inexpensive and very affordable!

We now have a bunch of higher-power Turbo-Engines running around...
like many of the members here have.
Gen-I and Gen-III/ Gen-IV SBC Engines are everywhere now...
Many of them Turbocharged and make decent power!

No one 30 Years ago, thought that Smaller Turbo V8s would be the Fuel-Efficient, clean Emissions making Engines that are seen everywhere now!

GM wanted all of this to happen by the Early to Mid-1990s.
The Turbocharger Technology was no where near good enough...
They were too hot, too dirty, required too much maintenance, and made too little power.

Now Turbochargers are as efficient (at making power) as all but the best Screw Superchargers.
Turbos way surpass Roots Superchargers.
They surpass Centrifugal Superchargers.
They are on par with some of the Screw Superchargers...
and it wont be long until they surpass even the best Screw Superchargers!!!
(Unless the Screw Blower Tech also improves).

 

This quite possibly the direction I'll be going.

 

Nice!

When I modify those Intake Manifolds...
I TIG weld the HVH Spacer to the Manifold, and re-shape, contour, port, and blend the Plenum opening and Spacer into one uniform opening.

The material/ areas that have Black Lines outlined, are removed and re-shaped to be more like a Single Plain opening:


The taller Manifold/ larger Plenum area, with the transition from the ported HVH Spacer into the ported shared Plenum space...
along with some Runner transition porting, and Port-Matching... really improve the already great performance of the Intake Manifold.
The HVH Spacer is shown Upside-Down in the Image Below:

 

ok got some info on my gen 1. 350 4 bolt 30 over. world products heads roller rockers summit 1102 cam, air gap performer intake with a Q jet. Does this combo make sense for my gen 3 92 z28 305

 

Yep.
Pretty much like any of the hot rodded 350's that are in these cars. More or less.
The devil is in the details regarding if that engine performs or not. But as for fitment, it'll drop right in.

 

I'm still in the planning stage. What do u mean by correct 350?

 

I believe he was referring to using a 350 Cylinder-Block/ Engine, that is of 1987 or newer Design...
that was produced to use a Hydraulic Roller Camshaft.

The older Design Cylinder-Block/ Engine would use a Hydraulic Flat-Tappet Camshaft.
This Design could use what is called a "Retrofit Hydraulic Roller Camshaft" and a Thrust-Button with Solid Timing Cover.

 

I like the concept and way that spacer extends into the intake - looks like they more or less took one of their standard 1" spacers and milled down the mounting surface. I could see where that would help a good bit on certain combinations.

I've had really good results using the big Brodix 1016 dual plane with a Street Sweeper spacer (below) on 406 combinations making upwards of 600HP. I've never dynoed the two, but I've built near identical 406 combinations using a Victor Jr and the 1016 with the Street Sweeper made better power based on the ETs and MPH - they shifted at the same RPM also. The dual plane combo was a good bit more responsive.





Not meaning to derail the thread (it's kinda related), but curious if you've ever tested one of the 1016 Brodix intakes. I'm pretty sure the Air Gap wasn't available back when I built those engines and wondering if the next one I build If I should go with the Air Gap.

 

Sorry, I do not have any Dynomometer Data for a Brodix 1016 Intake-Manifold.

 

Take notice between the two designs.

 

Without getting in High RPM (7,500 to 11,000) or High Power at High RPM Designs...
The Gen-I SBC Edelbrock Performer-RPM Air-Gap Intake Manifold is an AMAZING Part!

 

That visual gives an excellent representation of how difficult it is to actually get a defined runner length for the Air Gap.
Virtual engine building (Like the old DynoSim program I fiddle with) loses that input value whereas with a single plane, the runner length can be used for tuning an overall combination.

 

Seems the conventional thinking is that it too often benefits from a spacer or two as has been discussed.
I'm actually looking forward to getting to that tuning point. At the very least it'll mean heap is up and running again!

 

The reason I tried the Brodix 1016 with a Street Sweeper to begin with was an old Circle Track dyno comparison against what I think was an SP1 on a 406 making, best I can remember, around 540HP. I think that was in the mid-90’s (?) and I looked to see if I could find it on the internet.

I wasn’t able to find it but I did find the following dyno comparison on a 430-ish HP, 355. The combo isn’t really relevant to something I would build, but thought it might be worth posting
https://www.motortrend.com/how-to/su...fold-benefits/



While the single planes may be a little easier to look at to determine which one might be designed a little better than the other, looking at this dyno comparison, it appears dual planes aren’t as easy. That said, the above test was an RPM against the 1016 and I probably will try an RPM AirGap with the Street Sweeper spacer on my next dual plane build. I really like the air gap separating the runners from the intake floor - now that is an easily seen design improvement.