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BlackBird's Intake Manifold & Cylinder Head Testing Summary
After discussion with a couple of LS1TECH members, I decided to do a summary thread for lntake Manifold Flow Tests: LS1, LS6, TBSS, BBK, Dorman LS2, 102 Fast, etc: The original thread is sprawling and unwieldy. Later I will also add my data for LS3 & Wegner NASCAR spec 799 heads (early) but initially the data will be cathedral. Likewise, I may have an opportunity to test an additional cylinder heads at some point and wanted a consolidated placed forth results.
Special thank you to Land Speed Cylinder Heads and Brett Land & Jim Stewart for making the tests possible. Land Speed products are among the very best in quality 2nd performance. Brett has an outstanding career with Katech and Jim with Cosworth. Sadly Jim was taken from us way too soon last year. Our dear friend is sorely missed.
99 BlackBird's Flow Testing - Cathedral Intake Manifolds, all. testing was done on the same SF1020 flow bench. This is a heartbreaking bench. Reader digest version. Most ported stock cathedral heads won't break 300 cfm on this bench.
Skip next two paragraphs unless you like details on flow testing
The bench is regularly calibrated, we tested a reference before and after to ensure the results were as accurate as possible, all tests were done on a 4 inch bore, at 28, no pipes were used, bare heads had a normal clay radius. This specific SF1020 reads low even for an SF1020 On the plus side this was in my opinion the perfect SF1020 because it doesn't yield l over inflated numbers. On a reference part of my own, this bench was nearly dead on with another flow bench I had used. Wegner Automotive Research's NASCAR head development bench back in 2001-2004. Both bench are notorious for knocking 20 to 25 cfm off of some numbers claimed.
Flow data is only a starting point for cylinder head & intake manifold development and evaluation. The real tests are dyno results and what's it run at the track. The flow testing is basically the tool I could afford to provide data to the LS1Tech community. Others may get different results depending on the flow bench used and their diligence or lack off with testing procedure.
Three heads were used.
GMPP ported 243's with stock valves
Revised GMPP 's with mid lift valve job & chamber work
Early Wegner 799 Nascar spec heads w/Titanium valves
The data
Added pictures of two outstanding ported manifolds, Mamo MSD Stealth Mamo 102 LSXR on there flow bench.
Last edited by 99 Black Bird T/A; 07-07-2019 at 09:12 AM.
Summary of my impressions from flow testing, DynoJet testing, and observations over the last 20+ years for NA applications. Assuming the parts are correctly matched for horsepower. Others may view differently & I respect that
From worse LS4 to first ported MSD.
LS4 - you know it's garbage if an LS1 intake out flows and out powers it.
LS1 - With or without EGR, same results NA, good for base line testing, works well for forced induction or NOS. I'd favor the non-EGR LS1, it looks better and probably less likely to leak under boost. If it blows up - get another one for $50 to $75. Non-EGR version easily confused with an LS6 at a glance. LS1 has curved bottom. LS6 is flat.
Dorman LS6 - Sounds promising, however it's sometimes more of a 73mm snout opening intake than a 78mm stock size snout. You can hog out the snout to improve. Out of the box it's not what we want for an LS6 replacement. Dorman definitely got noticed with this offering. Better Dorman stuff is on down the list.
LS2 intake - Good design & 90mm snout. You know FAST probably soiled themselves at first glance. This should been, could have been, would have been the bomb - if intake didn't leak air between runners which is bad for NA. Forced induction all good until the sonic welded seams fail and it splits
LS6 - Excellent proven factory intake that's affordable used. New in 2002 for $400 and still see the listed in Marketplace for $350 to $400. Few parts hold value for over 15 years. The intake will fit almost all applications with low hoods.
Dorman LS2 90mm - much better overall than the Dorman LS6. Good construction and 90mm snout. The Dorman LS2 intake flows better than a stock LS6. DLS2 also has room for improvement. Touching up the runners helps with higher lift flow. I would like to know what an all out porting can do. Being two pieces probably not the ideal intake for demanding FI. Stock LS1 fuel rail fits. Needs TB cable bracket for cable TB's. Fits low profile hoods generally.
TBSS - The best factory cathedral intake. Best value too as often sold for $160 to $250 with fuel fail and injectors! Negative is its tall and won't fit under low profile hoods easily. Shaved the TBSS can even look as fantastic as it performs. The intake makes good top end power and pumps up the torque curve. With all the GM trucks on the road this manifold should in demand and be $400.
Ported Dorman LS2 - Dorman stepped up their game dramatically with this manifold. Fast inspired lower shell from a Fast 78 and an LS6 based user shell with a true 90 mm opening snout. The stock manifold flows well to .500 lift and can benefit from basic clean up above .500 lift. With retail around $445 this is a good manifold at at reasonable price. When Rock Auto was under cutting pricing the Dorman could be had for about $325. For cable TB needs bracket. Potential for 485 whp and maybe more with the correct supporting parts. Fits under low profile hoods well.
SuperAuto - this looks like a baby LSXRT and was the best flowing 78mm snout intake in my testing. Keeping with a 78mm stock/ported stock LS1 style TB if this intake fits under the hood it's most impressive on the flow bench. This was probably the most surprising intake in the test. With good port work if should improve.
BBK - the aluminum intake is good based on flow data. Potentially an excellent intake for high boost being metal vs plastic or nylon. The 85mm snout has room for porting. Likewise the runners have ample space for porting. While an all out extensive porting would probably be very expensive it would be interesting to see how much air this intake could flow.
Ported TBSS - Given the low cost of a used TBSS a good porter can really wake this intake up for minimum cost. Basically cartridge Roll clean up for the runners and a few other tweaks go along way. If the TBSS fits it's a great intake for low cost. The intake manifold gaskets can be hard to find as they are different than the other LS manifold gasket92.
LS6 TPiS/LPE 90mm - LS6 intake in hand and the TPIS/LPE 90mm snout can be a nice $350 mod for good airflow gain. Stock snout really restrictions the LS6. The LS6 has a smaller plenum volume than the aftermarket intakes in most cases. In my experience this intake works well on 346 & 383 LS engines. Easy to tune for excellent drive ability. In back to back testing it drove better than the Fast 90 on my car. Mine has been trouble free for three years and 10,000 miles.
Per LPE, LS6 90mmusually down 5-10 whp im dyno testing vs the Fast 90/92 on the typical street 427 build.
The LS6 runner flows max of ~265-270 cfm depending on flow bench and the cylinder head used for testing etc
Selling your LS6 for $350 to $400 towards a used Fast can also be a good option if a decent used Fast 90/92 is available.
Fast 90 - Excellent intake, out of the box. Great deals can be found used. Flows well & makes excellent power. Easy access for porting. So popular a new and improved version the Fast 92 appeared. The bigger runners max flow ~275-280 cfm depending on flow bench and the cylinder head tested.
Ported LS6 TPiS/LPE 90mm - Peak Speed did radical port. The plenum gained volume and definitely looks better. On the flow bench the LS6 runner didn't respond as well to clean up as I'd hoped. Suspect as the cam lift goes up the Peak Ported runners will probably help. Removing supports inside probably helps too.
Spending $400 towards Johnson or Morel lifters probably better choice. However, there are limits to flow bench testing and engine dyno would be the real way to measure.
PeakPorted LS6 TPiS/LPE 90mm bested both a 102 LSXRT (2 peak hp) & Fast 90 (3 peak hp) in back to back dyno testing on my small cam 383 stroker. It had a fatter hp and torque curve at all rpm tested. Big cam and high rpm the Fast intakes would have prevailed. Max rpm in the test was 6,500 and the car was out of cam ~6,000 rpm. The trick LS6 proved best in normal driving - basically stock
Ported Fast 90 - drives very good, a typical tuner can sort one out with good results, makes excellent power, well proven, priced right used. Bigger plenum yet well matched for smaller engines up to 408's and can still do very well on bigger 427's too. A most versatile & flexible aftermarket intake IMHO. Quality porting just makes it better
For 400+ cubes the bigger intakes are well worth considering.
Fast 92 - see comments for Fast 90 , improved revised version with better airflow. More expensive used than its older brother. Has more potential ported accordingly placed here.
Ported Fast 92 - see Fast 90 & Fast 92 comments for details. Just gets better with quality porting.
Super Vic - aluminum intake, 3rd best based in my flow testing. Potentially an outstanding intake for NA & forced induction. The plenum material for porting. Runners have material for porting. In my testing we didn't have an ideal port match. Port matched and all out extensive porting (expensive) it would be amazing to see how much air this intake can move. Suspect total lost flow could be 3 to 5 percent. A 325 cfm head might flow 315 cfm with this intake correctly ported and matched.
MSD - stock not ported, based on two unported MSD's I've seen apart, I honestly wouldn't run one unported. The intake is designed for higher rpm with matching parts and needs the porting clean up to excel. Others will probably disagree.
Fast LSXR 102 - proven performance intake makes excellent power on all set ups from stock cubes to ~427 cubes. Tuning skill determines drive ability -excellent to horrible. 102TB set up can be challenging to tune with cable throttle bodies. More cubes help. Mail order tuning can ease the pain. Frost has an excellent reputation from what I've gathered. This intake has been used on high effort bolt on Ls1 cars and made 400whp + and one bolt-on LS6 made 450+ whp
Ported Fast LSXR 102 - think Fast 102 LSXR just better will make more power and peak slight higher in most cases.
LSXRT - Key questions:
Will it fit under the hood?
Do I have access to a fantastic proven tuner?
Does that upturned snout allow102 mm air tube in the engine compartment?
If the answer is YES to all proceed. Otherwise get an LSXR and avoid much grief. Had one on my 91RS with drive ability issues despite over a half dozen professional tuning attempts. My impression LSXRT well suited to 400+ cube engines and extremely finicky on 383 and smaller engines with a cable drive TB. These long runners even in stock form can move some serious air. Cam accordingly.
Ported LSXRT - LSXRT on steroids. Several years ago a former Ford intake engineer shared he saw a ported LSXRT dyno within 10 hp on a 1,000 hp engine of a custom sheet metal intake that cost five times as much. This can be a very formidable intake manifold.
Ported MSD- in the hands of a skilled expert porter like Tony Mamo this is an outstanding intake manifold if you've got the matched heads & cam for rpm and air flow. I'd skip an unported MSD from what I've seen. This manifold really needs some love shine and careful assembly to avoid leaks.
Last edited by 99 Black Bird T/A; 07-05-2019 at 04:05 PM.
This is my pet way of thinking about airflow. Cam lifts valve off of seat, add flow for each test point going up, then peak, then add airflow for each point on the way back to the seat.
I like to consider total and average forth number of data points. Not saying that small differences are critical but with enough data think it can help evaluation.
I decided to include testing the early style Wegner head with two intakes: The 90mm LS6 and the Super Vic.
We discovered I had over looked an O-ring intake gasket for the Super Vic. I had assumed it used an LS1 intake gasket. The intake isn't machined for an LS1 intake gasket. The shop didn't have a gasket for the Super Vic either. We decided to improvise and make our own with a thin layer of grease on the face of the cylinder head intake port. Luckily the head and the intake are flat and sealed up good. With port matching the Super Vic will flow more air. We tweaked and adjusted several times for best alignment.
The Wegner head is a good head for its application but it wasn't what I was looking for so we didn't test additional manifolds with the cylinder head.
The Edelbrock Super Vic is a nice intake. Nice open straight shots to the cylinder intake ports. The SV is tall probably about 7 inches so hood clearance maybe an issue in some applications.
The TPiS LPE LS6 90mm snout. Its low and fits most applications.
The flow data. The TPiS LPE LS6 90mm snout flowed within 10 cfm of thd Super Vic with the Wegner head. What a surpise!
Last edited by 99 Black Bird T/A; 07-07-2019 at 09:00 AM.
Edited post - Decided to include my data on LS3 intakes collected too. My carpal tunnel was too yesterday to add it.
Test conditions were different than the cathedral testing used 4.060 bore and no clay on head for LS3 tests.
Summary
Here are the flow bench numbers for the cylinder head, LS3 intake + head, WS6STORE / VR ported LS3 Fast LSXR intake.
The head is placed on the flow bench and flow tested. Then the respective intake manifolds were bolted to the head and flow tested. I think the factory LS3 intake is pretty good but the WS6STORE / VR ported LS3 Fast LSXR intake blows it away on the flow bench.
We found an interesting result and to ensure accuracy re-ran the entire series of tests to confirm the results.
All testing on SF-1020, at 28 inches with a 4.060 bore. The owner told me this SF-1020 typically reads 15-25 cfm less than the typical SF-600. Previously, many know cylinder heads that claim 300+ cfm of flow delivered ~280 cfm on this bench. Based on data collected in another set of tests this SF-1020 tends to flow very similar to another heart breaking flow bench one of my NASCAR friends used to test several sets of heads. In short, I think these flow numbers are as accurate and fairly measured as is possible for an enthusiast to acquire.
A few comments on the testing. I took a WARR 92mm TB and a pair of Nick Williams 102 TB's to also test with the intakes. The TB's had no effect on the flow numbers. The WARR 92mm TB bases on flow bench testing does not restrict the stock LS3 intake. Neither of the Nick Williams TB's had any effect on the WS6 / VENGEANCE Racing Ported LS3 LSXR intake. Engine dyno testing might show an effect but flow bench didn't.
No clay intake radius was used on the cylinder head. The intake port was tested bare. No pipe on exhaust.
The two gray column are the,Darin Morgan Reher-Morrison CNC'd LS3 cylinder head intake and exhaust flow in cfm
The blue column is LS3 intake & RM head, note the LS3 intake kills up to ~50 cfm of flow similar to what an LS6 intake does with cathedral heads.
The green column is the WS6/VR ported LS3 Fast LSXR intake. It reduced flow by a small amount at high lift and helps enhance low lifters flow.
The pink column shows how the WS6/VR ported LS3 Fast LSXR intake.increased or decreased flow at various lifts compared to the bare RM head.
This was the very first time I had actually saw an intake manifold match with a cylinder head so well that it enhances flow any any lift.
I did notice the cylinder head intake port sounded crisp & clean when being flow tested. Some cylinder heads have a muddy turbulent sound when they are flow tested. A cylinder head with a dirty sounding port usually isn't a very good head.
Note dyno and track testing are the ultimate measure to make judgements by not flow bench numbers. I think flow bench testing when properly done can help us evaluate parts.
Note - with a baby cam & the LSXR intake the heads made 517 whp 471wtq in my 99 T/A w/Magnum T56, RXT clutch, Hawks 8.8 & 4.11 gears. Typically the heads hit 500whp to 550 whp depending on cam selection, tune and other details.
Last edited by 99 Black Bird T/A; 07-07-2019 at 08:36 AM.
Kidding. And thanks again for the big contribution to the community. Honestly the test helped me better understand manifolds. Not so much a matter of which one flows best - more like which restricts the heads the least
Darth, lol indeed, pure classic "Suck it up Buttercup"
Intake manifolds do generally seem to restrict the heads more than anything else. There's definitely a trend with the 102 intakes flow very well and flowing even better when ported by an expert like Tony Mamo or one of the other outstanding porters like Darin Morgan, Bret Land. There are others I'm just more familiar with the work of names mentioned.
Originally Posted by Ls7colorado
I know its not listed and hate to be "That Guy" but any idea were a Vic Jr would fall in this?
thanks for the awesome writeup!!
Thank you
Vic Jr vs Super Vic
I think on a 400+ cube engine or a high winding LS, the Super Vic would really outshine the Vic Jr. I'm mostly guessing that based on what I've read about the intakes when used on other engines. On a nice street friendly engine that isn't being spun ~6,500+ rpm the Vic Jr would probably work well and be less hassle to fit under most hoods. Under 6000rpm I don't think it would be a much difference.
I've read according to Edelbrock, and various engine builders/dyno operators with ~4 inch bore, or up to 400 cubes, one can use a victor jr. A 1 inch spacer probably helps if it will fit on carb set up. A high rpm engine or 400+ should benefit from the super vic. I've heard of 400+ gaining ~25 to 30 hp with a Super Vic. I have no direct experience to back up my speculation.
If the Super Vic fits, it'd be hard to use the Vic Jr.
I can really appreciate the time involved both conducting these tests as well as the time invested typing about it.....trust me I can relate to both situations but just wanted to say great job and collating all this data you have been slowly collecting is really helpful IMO. The first thread simply had it spread out everywhere by the time it ran its course so to speak
So I see both my ported MSD and ported FAST 102 look solid and I thought that the "total" number you included (adding up the flow in both directions) was an interesting data point and very valid in most respects to output (but a higher RPM combo would still like a slightly weaker area under the curve in favor of more top end flow if complimented by a slightly shorter well designed runner).
That being said I do still feel that my ported 102 FAST is the best choice for the masses while my ported MSD is the best choice for a select few building a more purpose built higher RPM combo (and willing to trade low midrange torque for higher RPM peak power and a flatter curve with a slower roll off past peak extending the gains even further there).
My million dollar question and one of the main reasons I hopped in here (besides the kudos!).....Is the FAST 102 I ported and the MSD I ported both tested with the same baseline heads?? That's very important thing to quantify if we are to really going to compare the numbers. I believe that is the case but I just wanted to confirm.....looking at the flow numbers it would look like something I would have expected to see with the same head used as the baseline.
Also guys.....higher flowing heads can change some of the stats in an interesting way.....I bet the ported MSD I did would have beat the ported FAST in total "points" had the heads flowed even more placing an even higher demand on the intake manifold in question....I think the MSD would have shined a touch more there but even in that scenario.....if the build will primarily see 6800 RPM or less, the ported FAST would likely provide the highest average power and torque numbers.
Good stuff.....once again fantastic job with all the data collection and the time you invested Wade
Tony thank you for taking time from your busy schedule to comment! That really means a lot to me
The Mamo LSXR was tested after the heads got the revised mid-lift Valve Job. The Mamo MSD same heads but the original valve job. To me that makes the peak numbers with the Mamo LSXR that much more amazing sincere heads aren't optimized for .600+ flow.
I expected the Mamo LSXR to do well in the test but am pleasantly surprised with the overall results.
Tony just wondering which engine applications do you like to use a Mamo ported Fast 90/92 intake manifold in?
One of the details the numbers can't directly show is how wonderfullyclean, crisp and turbulence free the Mamo MSD, Mamo LSXR & Peak Speed ported TBSS all sound on the flow bench. I think in a running engine that characteristic will translate into more power under the curve due better cylinder fill. Cleaning the runners up is a good thing. Even the Peak Speed radical ported 90mm LS6 & WS6 Store ported Dorman LS2 sound cleaner than they do unported.
I've learned from the testing, I want at least at 90mm snout on any manifold in an NA engine build or heads and cam package. Likewise the TBSS is clearly an outstanding manifold from GM. The LS6 is still pretty good with a 90mm snout. Likewise for the serious airflow the 102 intakes are where it's at.
Last edited by 99 Black Bird T/A; 07-06-2019 at 11:44 AM.
One of the details the numbers can't directly show is how wonderfullyclean, crisp and turbulence free the Mamo MSD, Mamo LSXR & Peak Speed ported TBSS all sound on the flow bench. I think in a running engine that characteristic will translate into more power under the curve due better cylinder fill. Cleaning the runners up is a good thing. Even the Peak Speed radical ported 90mm LS6 & WS6 Store ported Dorman LS2 sound cleaner than they do unported.
I would bet this means more than many might think! Turbulence in a manifold is not welcome. The straighter the shot without any "distractions" the better the flow, I would think.
Are there any intakes for a 427 TT 1300 rwhp street setup that will fit under a stock SS hood/uncut cowl that would work good at that power level? Hydrolic setup with trick flow 245's that will never see past 7500 rpms? Sniper EFI low profile perhaps? That's going to have a 10% difference in airflow from the worst cylinders to the best, correct? Can 3% or less variance be had and still be under the stock hood/cowl and what intake would that be?
Are there any intakes for a 427 TT 1300 rwhp street setup that will fit under a stock SS hood/uncut cowl that would work good at that power level? Hydrolic setup with trick flow 245's that will never see past 7500 rpms? Sniper EFI low profile perhaps? That's going to have a 10% difference in airflow from the worst cylinders to the best, correct? Can 3% or less variance be had and still be under the stock hood/cowl and what intake would that be?
Hopefully someone else can make an informed suggestion, I've not done a forced induction build as I find NA applications my primary interest.
Seems to me having heads and intake manifold ported, hand touched up together as a unit and tested would probably be a reasonable way to get the difference in flow as small as possible.
While I'm a big fan of cathedral style heads, the BTR intake comes to mind for that sort of rpm too. However, for your 7,500 rpm high hp application, rectangular port heads and something like an LOD intake manifold might be beneficial. The LOD might require spacers to move the K-member down to get the LOD to fit under the cowl. Some cutting might still be needed.
BTW - edited post #3 or #4 and added some LS3 intake flow data, plus the cathedral data for two intakes with an older set of Wegner NASCAR 799/LS2 heads.
07-05-2019, 08:22 AM
BlackBird's Intake Manifold & Cylinder Head Testing Summary 
On the plus side this was in my opinion the perfect SF1020 because it doesn't yield l over inflated numbers. On a reference part of my own, this bench was nearly dead on with another flow bench I had used. Wegner Automotive Research's NASCAR head development bench back in 2001-2004. Both bench are notorious for knocking 20 to 25 cfm off of some numbers claimed.
