RHS 170cc vortec airflow

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Ron Golden
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RHS 170cc vortec airflow

Post by Ron Golden » Mon Dec 27, 2010 8:18 pm

Has anyone here flowed the RHS cast iron, 170cc, 2.02/1.60, Pro Torker vortec head? We're building a 10:1, 358 SBC mule motor for our new dyno with thoughts of eventually marketing an inexpensive (?) "crate" engine for mild street applications. Has anyone dynoed a similar combination? HP & TQ?

Thanks, Ron

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Re: RHS 170cc vortec airflow

Post by randy331 » Mon Dec 27, 2010 10:52 pm

Ron, the RHS # 12410 head, with a 2.02" valve with a 30* backcut, with a 4.060" test bore, on my bench flowed,

.200---143
.300---198
.400---233
.450---244
.500---246
stall above .500

I know you didn't ask, but the RHS #12407, with a 1.94" valve, with a 30* backcut, on the same test bore, and bench flowed,

.200---135
.300---188
.400---230
.450---241
.500---241

The 12407 is about $75 less, but doesn't have the dual bolt pattern for the intake manifold.
If you look at valve discharge, the 12407 is better everywhere.
On the 12410 head RHS claims 27 more cfm than a stock vortec head, but it comes up way short on my bench.
The stock 062 vortecs flow about 235 on my bench. 235+27=262 the way I add, but I'm not that good at math, so I may have not added right!!

I ported a set of the 12410s for a 10/1 comp 355, for my sons 4 wheel drive truck. It wasn't dynoed, but it makes more power than a 17 year old needs. I went with the 12410 because I wanted to use a ported performer rpm, or a stelth I have, but after running it for awhile, I put an unported out of the box Edelbrock 2701 performer eps intake on it, to lower the rpm some. Now I wish I had went with the 12407 since I've bought the vortec intake anyway.

Randy

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Re: RHS 170cc vortec airflow

Post by Ron Golden » Tue Dec 28, 2010 12:14 pm

Randy,

Thanks for the info, that's exactly what I needed. By the way what kind of flow bench did you use?
The longer I mess with this crap the less I know.

Ron

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Re: RHS 170cc vortec airflow

Post by ProPower engines » Tue Dec 28, 2010 5:16 pm

RHS advertize flow numbers are done using a 4.200 bore I went through this a couple weeks back Called and got the tipical salesman answer regarding it as to why its an industry standard. But they used a bigger bore to make them look better.
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Re: RHS 170cc vortec airflow

Post by 78vette » Tue Dec 28, 2010 6:27 pm

You may want to look at Enginequest Vortec heads also. I just bought a set and ported them myself, (first time porting- followed info here and by Joe Mondello)
they flow 259 @ .400, 277 @.500. 286 @.600 on the intake with 1.94 valves. They are very nice castings and they have several combinations of intake faces and center bolt or perimeter bolt valve cover. I did not flow them before porting but they are supposed to flow as much or more than a stock vortec.

Randy

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Re: RHS 170cc vortec airflow

Post by Ron Golden » Tue Dec 28, 2010 8:26 pm

Thanks guys for the info. We plan to run several combinations of heads, cams, intake, EFI, etc on the short block before we decide if we want to market the engine. I think it'll be fun. Plus it will answer lots of questions that I've never had the time to research/test before.

Ron

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Re: RHS 170cc vortec airflow

Post by randy331 » Tue Dec 28, 2010 9:51 pm

Ron Golden wrote:Randy,
By the way what kind of flow bench did you use?
The longer I mess with this crap the less I know.
Ron
First I want to make it clear my flow numbers posted earlier in this thread on the RHS heads were as cast flow numbers. (no porting) I tried to edit my first post to say they were as cast, but I couldn't seem to get it done.

Ron, my flow bench is a home built unit. I've compared it to several super flow benches, and it's very close to them.
Most others report 235-236 range on the 062-906 vortecs, and that's right where my bench shows them to be.

On a crate type engine, I'm not sure you could add enough on to the price, to justify porting, so I guess the best flowing as cast head would win the PR sales contest.

Randy

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Re: RHS 170cc vortec airflow

Post by F-BIRD'88 » Wed Dec 29, 2010 4:28 am

RHS's +27cfm claim is accurate when comparing unported 062 vortecs (with just a 2.02 valve job cut in) against their Pro torker vortecs 2.02. My 062 vortecs flowed 228cfm box stock factory valves and 218cfm after just cutting in a 2.02 3angle valve job with no bowl cut etc. Thats right -10cfm from stock. 218+27=245cfm.

Having messed with a few pairs of vortecs before.
Your numbers look very real/accurate for the out of the box RHS vortecs. They are what I would have expected from these heads in out of the box form on a realistic bore size.

My vortecs ended up very well once correctly finished with 2.02-1.60 but the initial 2.02 rough in valve job killed 10 cfm from stock. This was not a surprise to me as I had read this would happen, and it did.

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Re: RHS 170cc vortec airflow

Post by Keith Morganstein » Wed Dec 29, 2010 4:53 am

78vette wrote:You may want to look at Enginequest Vortec heads also. I just bought a set and ported them myself, (first time porting- followed info here and by Joe Mondello)
they flow 259 @ .400, 277 @.500. 286 @.600 on the intake with 1.94 valves. They are very nice castings and they have several combinations of intake faces and center bolt or perimeter bolt valve cover. I did not flow them before porting but they are supposed to flow as much or more than a stock vortec.

Randy
The EQ heads are nice. The castings and and the ports are super clean compared to a stock vortec. There can be some issues with rocker stud pad height though. (have had to mill them down for shaft rockers)



EQ CH350C (vortec replacements) opened up to 2.02/1.60 and blended from the VJ into the bowl. No porting.

SF 600 Bench. 4.060 bore

Lift - I / E

.100 - 79 / 56

.200 - 153 / 94

.300 - 200 /149

.400 - 238 / 177

.500 - 255 / 186

.600 - 266 / 193

(stalled at .625)

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Re: RHS 170cc vortec airflow

Post by ap72 » Wed Dec 29, 2010 11:53 am

78vette wrote:You may want to look at Enginequest Vortec heads also. I just bought a set and ported them myself, (first time porting- followed info here and by Joe Mondello)
they flow 259 @ .400, 277 @.500. 286 @.600 on the intake with 1.94 valves. They are very nice castings and they have several combinations of intake faces and center bolt or perimeter bolt valve cover. I did not flow them before porting but they are supposed to flow as much or more than a stock vortec.

Randy
286cfm with a 1.94" valve?! That's incredible! Can you share some details? What depression were they tested at? Volume, min csa? Valve/seat angles/widths? Throat diameter?
LOL, according to the post count I'm an "expert." The only thing I'm an expert at is asking questions.

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Re: RHS 170cc vortec airflow

Post by 78vette » Wed Dec 29, 2010 6:16 pm

ap72 wrote:
78vette wrote:You may want to look at Enginequest Vortec heads also. I just bought a set and ported them myself, (first time porting- followed info here and by Joe Mondello)
they flow 259 @ .400, 277 @.500. 286 @.600 on the intake with 1.94 valves. They are very nice castings and they have several combinations of intake faces and center bolt or perimeter bolt valve cover. I did not flow them before porting but they are supposed to flow as much or more than a stock vortec.

Randy
286cfm with a 1.94" valve?! That's incredible! Can you share some details? What depression were they tested at? Volume, min csa? Valve/seat angles/widths? Throat diameter?
I thought that was really high also. I am not an expert on this stuff by any means. If the exhaust wasn't so low I would not have believed the intake. They were tested at 28" with a 4.060 bore fixture. I opened up the push rod pinch to about 1.96, I did not check the port volume- I did not take a lot out of the ports, just cleaned them up with a carbide and then cartridge rolls and made everything nice and straight. The throat was 90% on the intake- because of the way the seat and bowl was in the exhaust I only opened them up to about 87%. I should have went with 1.6 on the exhaust and opened them up more because they did not flow as well.
I don't know the valve angles, a local guy with a good reputation (Kim Barr) did the valve job and the flow- I know it is a 5 angle. If you are really interested I could find out.
Here are the complete numbers.
Lift I/E
.100 87/70
.200 160/ 117
.300 217/ 143
.400 259/ 165
.500 277/ 171
.600 286/ 174

Randy

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Re: RHS 170cc vortec airflow

Post by the nitro man » Thu Dec 30, 2010 1:03 pm

by ProPower engines » Tue Dec 28, 2010 5:16 pm

RHS advertize flow numbers are done using a 4.200 bore I went through this a couple weeks back Called and got the tipical salesman answer regarding it as to why its an industry standard. But they used a bigger bore to make them look better.


lord knows everybody has a sbc with a 4.200" bore.

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Re: RHS 170cc vortec airflow

Post by Newold1 » Wed Aug 09, 2017 6:40 pm

RHS's comments on using a 4.200" bore size for flowing an SBC sounds like it deserves the old saying. "IF YOU CAN'T DAZZLE THEM WITH BRILLIANCE , THEN BAFFLE THEM WITH BULLSHIT!"

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Re: RHS 170cc vortec airflow

Post by JodyB » Wed Aug 09, 2017 9:05 pm

Hate to be "that guy", but have you considered the 200cc aluminum china dart head copy? Many are using it as a core for their cheaper cnc heads.

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Re: RHS 170cc vortec airflow

Post by Keith Morganstein » Wed Aug 09, 2017 9:39 pm

I was reading this, and thinking of posting about EQ vortecs,

But, then I saw that I did post on this thread... Almost seven years ago! #-o

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