I'm currently running a mildly worked Holley stealth ram intake on my 414 combo. It is gasket matched and blended at the top of the base and the runners were smoothed but basically left stock in size. Heads are AFR 210's and cam is a roller 236/242- 600 lift with a 58mm TB. I have not had this engine dyno checked but mid range power is great and it pulls hard to 5-5500 but seems to flatten out by 6000. I am considering a conversion to a single plane intake. However, I like how the HSR looks so it needs to be worth the effort and expense power-wise.

First, what power improvement might I expect?
What is a good 2015 era single plane intake choice?
Should I use the 58mm TB with an elbow or use a vertical flow TB?

All comments or discussion is appreciated.

 

does your afr heads have a vortec intake bolt pattern? if so ive got a cheap single plane in the for sale section that just needs a fuel rail mount fixed on it and you can try for yourself and find out how much better you like it haha. text me at 513 969 6156 if you can use it

 

I will need to check into this. I know it is not vortec specific but seems like it has extra bolt holes in it. What was your experience with single plane?

 

I had mine on a 327 that saw about 7000 safely and it didn't seem to have any breath issues anywhere I just didn't wanna blow it up going any higher lol

 

Subs.

I have a similar combo 415cui, AFR210, similar cam and had a HSR, swapped to a SP last year.

But since the HSR was max ported and the SP was stock it wasn't a fair comparison.

Will have the SP ported until next year.

/N.

 

My TBI swap to port fuel with SP did not affect the ability to rev smoothly to 6000 rpms. Seems SP got there much quicker. However I had adequate air flow in both setups. I used a Edel Victor E SP with 1000 cfm Edel throttle body. throttle response was 100X better. Both cases Edel RPM heads.

 

I doubt you would see much of a difference (maybe a couple hundred RPM) going from a HSR to the best of the off-the-shelf single planes. The HSR shouldn’t be a choke point on your engine and I’m thinking that you COULD have more of an exhaust or valve train issue than an intake issue.

The single 3.5” shouldn’t be that much of a pinch-point, so what muffler are you running? Most single outlet mufflers flow better than the dual outlets.

Assuming that there are no kinks in the pipes and a good 3.5” muffler, I’d start looking at the valve-train. I’m assuming this is a hydraulic roller - what lifters are you running and how much pre-load do you have on them? What valve springs are you running? I’m assuming you changed the springs (210s typically come with solid roller springs). If so, do you know the specs on them? What was the installed height?

If all that checks out OK, is the cam the typical 110 lobe spread? Did you degree the cam? The Comps typically come with 4-degrees “built in” and I’ve seen people add another 4 to it and the cam ends up 8-degrees advanced. That can make one drop like a rock past peak - especially a smaller sized cam in a larger engine.

 

You don't have enough cam.. My 412" has a 224/236 roller cam and it's well done by 5500. Your cam isn't that much bigger, so I'd expect around a 6000-6100 rpm peak.

260/266 @ .050" 106lsa is about what you need if you really need the RPM.

Personally, I'd put forced induction on it. A motor that shifts at 5500 will last forever, have a nice idle, great part throttle.

-- Joe

 

On big inch motors with enough head flow, a single plane should outperform the hsr since hsr is usually limited to 1205 port size. I have seen big gains on a 512 whp 406 switching from a 1205 miniram to 1206 victor e efi sp

 

Ok guys a lot to address here. Cam is on 112 and degreed in at spec which is 4' advanced. Springs are AFR upgrade for hyd roller. Small diameter not solid roller spring. Exhaust should be good with mandrel bent and dynomax ultra flow straight through muffler. Headers could be a problem with 1 5/8 shorty hookers. Stock Y inlet with k&m filters and cut out boxes.
interesting comment about forced induction. Are you thinking turbo or centrifugal blower? I don't really need to rev higher just seemed flat. I really need to check it on a dyno to see where it makes power.

 

Shorty headers at that size are gonna hurt you alittle bit. Intake swap wont help that

 

Lol no doubt.

 

Why not try an exhaust change first? Dyno don 1 3/4 shorty if you need shorty

 

Makes sense. I wonder if there is a way to test for header restriction. Are there any indications in the data log that may provide a clue? It would be interesting to know what kind of difference it would make. Probably need a dyno to really quantify the results. That's probably what I need to do first anyway. Maybe I just got used to the extra power and just think it's tapering off.

 

Probably have to dyno to see whats up. But a good sized sbc with decent exhaust ports in the head should run atleast a 1 3/4. That atleast covers the exhaust port on those heads

 

I agree with Orr on all accounts. I should have specified that there wouldn’t be much difference between the HSR and a “good” single plane assuming the HSR had been ported to a 1206 gasket – not just gasket matched, but ported the entire length of the intake. There are some single planes that would have trouble matching the power output of the stock HSR as evident in the “Ten Times the Torque” intake shoot out where a “small” Holley single plane feel short of the StealthRam at most all RPMs.

Headers definitely could be an issue – especially if the flange is overlapping the port. That’s quite common on a lot of off-the-shelf headers, particularly the smaller oval port headers. Most Hooker headers seem to have the “SAP” or “same as port shape” (kinda square), which tend not to overlap in the corners like the oval port shaped headers. However, the smaller headers still tend to be problematic on heads with larger than stock exhaust ports. Best way to know for sure is to pull the header and look. Any overlap can hurt and effectively reduce the size of the port more than just the amount of the overlap (due to turbulence).

I ran a 3” system with a single Dynomax Welded Ultra Flow with the dual outlets. It did OK with a 430-ish HP car running 12.3s on the engine, but it affected ET a good bit on a 150 shot – it just could flow enough (evident by the “ffffffffffffffff” sound from the exhaust). That said, if you’re running a 3.5” Ultra Flow “welded”, then that shouldn’t be an issue.

My money was on the exhaust system, but I’m still not convinced that it isn’t valve-train related. Good to hear you degreed the cam – a 112 set on 108/116 shouldn’t be problematic (a 108 spread set on 100/116 could have been). I think the pockets on the 210s are 1.58”, running 1.55” springs with the height set at 1.95”. When going with the smaller diameter spring, did you use a spring locator to keep them from wiggling/walking around? That could be more of less of an issue depending on how tight the retainers fit the inside of the spring. Do you know the specs on the springs and at what height they’re installed? Too little or too much seat pressure could affect performance. For instance if you have the 8019 springs, no locator, off-set retainers and/or locks and no shims were used,,,, if they were set to the “stock 210s” 1.95” height, you could have as little as 92# at seat and only 362# going over the nose.

How about the preload on the lifters? If they’re not already set to a 1/4 turn, you might try that to see if that helps before changing a bunch of stuff. Plus that should give you a good visual on whether or not there could be a setup issue on the springs.

 

Yes I agree on the primary tube size. When i was putting the new motor in the hookers were available and in my budget at the time. I noticed quite a mismatch between the Afr ports and header port so I welded the primary tubes on the outside of the flanges then I was able to match them to the gallergasket with out grinding through the tubing. The parts matched up very well although they were a bit funnel shaped due to the smaller primaries. Probably would be a good idea to upgrade to larger headers. I don't need short headers but chose them due to concern about ground clearance and fitment issues with long tubes. Do you think I should use long tube headers?

Btw hsr was gasket matched to Afr heads and the runners were smoothed and opened up slightly but not necessarily the whole way.

The motor was built by a reputable shop so i can't personally verify questions about spring height and cam installation. However I received a build sheet that stated the specs and I have faith they are accurate.

The heads came directly from Afr with the upgrade springs. I don't have the number but they are the optional hydraulic roller springs for the 195 heads. I expect that Afr set them up properly but do not know if the shop verified the setup. ???

The lifers are comps best short travel retro hyd roller lifters set at 1/8-1/4 turn.

 

Subbed for info

 

You might have read a thread on here or a few other sbc boards where the owner had a higher rpm engine and the rear cylinders were becoming starved for air. Although a bigger inch engine might suffer from this more easily. In that case a single plane is better, it equally splits airflow. Single plane also allows you to add the carb spacer to toy with added plenum volume. You also gain some room. I think the professional products single plane with an Accel throttle body is good and inexpensive combination. If you prefer an intake elbow with a ls1 or TPI throttle body I believe orr knows a guy.

 

What size accel carb style throttle body would you want to run on a single plane engine this size? Are the accel TBs a pretty good unit vs say the Holley.

 

Can't comment on the Holley piece but I really like my Accel throttle body. I think it's a 1000 cfm. Idle air and tps and vacuum port provisions. When you press the pedal half way down the first two throttle blades open half way. After half way the second two blades begin to open so both are fully open at full throttle. Makes driving around town easier and it allows for almost two separate VE tables on the same VE table.

 

That used to drive me whacky when trying to tune it with the '730 ECM. When the secondaries opened up it was another blast of sudden air, and it would get a lean pop.

If I recall it required a lot of AE vs tps work.

Are you using regular AE or EAE ?

-- Joe

 

Me: 350 cid, victor jr single plane, Edelbrock 1000cfm TB sequential, EBL. no crossover since RPM heads. Runs just great. No AE problems or cold start issues. EBL has expanded AE tables so maybe that is important.

 

I think I'm only using regular acceleration enrichment. I've never heard a lean pop. It's possible my mixture leans out for a few millisecond id have to look at old datalogs. I'll look at my settings when I open it up next.

 

What's the difference in the AE functionality in the EBL vs $8D ?

With the exception of $EE on my Corvette, I have not used any stock stuff in over 10 years now. And the Vette is stock so I'm not really doing much tuning wise with it.

-- Joe

 

I'm using normal AE as well. Working quite well with the miniram, I just kinda wish I had gone sequential so I could trim the rear cylinders.

-- Joe

 

Why would you want to "trim the rear cylinders"? I ask because I run the HSR and my rear plugs always look darker than the fronts.

 

Oh just to update a few points.

I did end up doing a dyno tune on an inertia dyno. The original cam made 418WP at 58-6000. It was difficult to pinpoint because it was very flat and hadn't really "peaked" when I aborted the runs. So what I was feeling as running out of steam was probably just the fall off in torque from earlier in the rpm range. Some have questioned the power level but the rpm range tells it's still pulling up top.

I have since changed cams due to a drivability issue and now have a 229/239 on 114. Much better all around and actually picked up a mile per hour or two at the 1/8th mile and shaved a few thou off the et. Haven't dyno tuned yet but there not a noticeable drop in performance. Had to pull the motor to do the cam swap so I went ahead and checked out the top end and ported the HSR intake to better match the heads and open it up a little. Everything else is the same.

I'm probably going to keep the intake since it won't make a huge difference. If I were starting from scratch I would likely go with a single plane setup. Heck if I were starting over I would probably go LS but that's a different subject.

 

The answer is within your question

The LT1's had rear cylinder trims because the rear cyls always were more rich than the front. My ECU won't do 8 cylinder sequential as I only have 2 fuel drivers so I can't trim the rear cylinders. If I upgraded to a MS3 I could, but I don't wanna bother with adding a crank + cam trigger.

-- Joe

 

I have the MS3 extra, and I thought when I was configuring it I had the option to use 8 fuel drivers without a crank sensor if they were still batch or port. Enabling trim on certain cylinders for our systems.

 

I cant comment on 8E having never seen or used it. EBL is said to have expanded tables. AE TPS runs from 3% to 50% in 3 % increments. AE MAP runs 10 MAP to 80 MAP increments of 10 MAP. EBL AE has 6 different Tables/Functions. AE in Constants are four areas of use.

 

Hrmm. Yeah, ok you are right. Trim isn't tied to sequential.

I was thinking you needed sequential to use the cylinder select functionality, but you don't.

-- Joe

 

Just found this thread, I'm also working on an HSR --> SP conversion. I bought a ProComp efi intake + rails off craigslist and a Holley 4bbl throttle body from Summit. Had to use a spacer, because the throttle linkage was hitting the rails. The rails also screw up 700r4 TV cable brackets, my current hold up.

Looking to see if I can get more top-end power. I'm currently running a Vortec HSR, bone stock, unported.

-Dave

 

I ran that same intake in 2012, but with a different holley Throttle body:







-- Joe

 

 

I'm also running the procomp efi intake with a dry 454 tbi unit.

 

Tell me about your water pump and coolant pump setup.

 

Did it work well?

Were you running a 700r4 with it?

-Dave

 

It's an LT based 383 running a standard distributor, Jegs electric water pump and an EBL Flash

 

Worked fine, but required a cowl hood.

I had a manual trans at the time.

-- Joe