selecting an EFI intake

[grumpyvette]

: grumpyvette
Hello there!

I have a question that I'd like to ask you. I plan to
rebuild my engine soon and while I'm there, I'll upgrade
some parts.

Right now I have stock bottom end 350 with ported
(mild porting) #113 heads, LPE #219 cam, complete
superram and LT headers.

I've allready bought .020" over flat top SRP forged
pistons and SCAT I-beam forged rods 5.7" long. I plan
to do more porting on the heads and install larger LT4
(2.00 and 1.56") valves.

Also, I've allready bought Comp Cams cam:
Comp Cams XR288HR-10
Hydraulic roller
288 294 advertised duration
236 242 @0.050
520 540 lift
110* lobe separation

I'm aware that it's big cam for 350, but I'd like to move
the power band more up, into higher rpm range.

What I'm debating over is intake. There are 3 choices
that I have:




1. Fully port superram and use that.
2. Buy miniram
3. Buy modified HSR

What do you think would be best choice? First option
would be best for me financially, but I could sell
superram and buy one of other intakes instead.

Also, I've heard that miniram have some air distribution
problems (front cylinders running richer)??
Do you know something about that?

What about HSR? I've seen you name mentioned in
converstion about modified (for vette) HSR. Do you have
it available and if you do, what is the price?

I'm looking forward for any of your input.

Thanks,

Bruno

viewtopic.php?f=55&t=641&p=1004#p1004

http://www.speedwaymotors.com/RHS-1...MIxaWg5tXZ1gIVA6ppCh09DgVzEAYYAiABEgINIfD_BwE


http://www.westcoastoffshore.ca/Fue...ke-Manifold-w-Fuel-Rails-12903-KIT-P5412.aspx

it states it comes with the fuel rails , it fits standard 23 degree heads and fits vortec heads ,
and at $514 thats not a bad deal,for a high fow single plane SBC intake

 

[grumpyvette]

of the choices you posted, Id take #1,the super ram is a decent intake and if you already own one ID probably stick with that and put any effort into upgrading the cylinder heads which are a big restriction,

IF you select a HOLLEY EFI your going to NEED THIS INFO
http://www.holley.com/data/TechService/ ... 5rev11.pdf

IF your insisting on swapping to a new intake, Id suggest a 4th choice, below, either matches the cam you selected fairly well PROVIDED the compression ratio is up near 10.5:1 and the rear gear is a 3.54:1-3.73:1 and your using EITHER a manual trans or a 3000rpm-3200rpm stall converter, so selecting the correct head gasket and combustion chamber to get to that approximate 10.5:1 cpr range is important to making good hp with the increased flow rates.
now like most guys your on a strict budget, but do what you can, as the cash becomes available, but without decent heads, matched to a decent intake and low restriction exhaust are the basics your really beating a dead horse trying to get better performance, without the combo of gearing, compression, head and intake flow and cam timing matched to compression,
IM also forced to point out that NO AMOUNT of porting or mods to the stock heads will allow them to perform nearly as well as some of the better aftermarket heads, and the stock lower end will pose a few limitations
a set of heads like these (I POSTED BELOW) with the l98 plug angle and small combustion chamber will make a very noticeable improvement....(if the heads are restricting ir flow thru the engine the intake you select , no mater how good it is, won,t improve much) and L98 HEADS leave a good deal of potential un-tapped in nearly stock form, the stock heads only flow about 200cfm, ported you might reach 220cfm, aftermarket heads could get you into the 260-270 cfm range with that cam and a decent intake with some port work, which is wasted on a 200-220 cfm l98 port head

or
http://store.summitracing.com/partdetai ... toview=sku

or

viewtopic.php?f=69&t=433

http://www.airflowresearch.com/210sbc_rh.php


viewtopic.php?f=52&t=796

http://www.holley.com/TechService/Libra ... lInjection

http://www.edelbrock.com/automotive_new ... hevy.shtml

https://www.firstfuelinjection.com/services.html
http://www.cfm-tech.com/

look at the difference in port size before any porting

http://www.firstfuelinjection.com/products.htm

http://force-efi.com/weber.htm

http://www.corvetteguys.com/mass-airflo ... 4-cat.html

http://www.gmtips.com/3rd-degree/dox/ti ... t/port.htm

http://www.vetteweb.com/tech/vemp_0802_ ... index.html

currently Id suggest this intake as the best over all compromise
, it adds better than 1000-1200rpm to the stock tpi (JUST LIKE A PORTED SUPER RAM WILL) but even when ported , and using the larger bases and runners,the of the stock TPI base is a restriction, potentially the FIRST INTAKE is a better design in my opinion than the super ram or
a custom reworked stealth ram ,(Which has a slight edge in peak power over the super ram )but you give up a good deal of low rpm tq to get that, peak hp.TORQUE the super ram and FIRST intake tend to retain,
if you ever have doubts, about any component in a certain application, the first reasonable step is to carefully read the advertizing and spec sheet info, AND THEN CALL the manufacturer for more detailed info if you can., you might be surprised but a lot of times asking for a transfer to the engineer department vs the sales guys is also a much better course of action when looking for confirmation on component use. info.

read these related threads

viewtopic.php?f=55&t=823

viewtopic.php?f=55&t=431

viewtopic.php?f=32&t=430

viewtopic.php?f=55&t=1202

viewtopic.php?f=55&t=431&p=530#p530

viewtopic.php?f=55&t=1052

keep in mind the stock TPI was designed to maximize torque in a 305 displacement engine at under 5000rpm, when you boost the requirements to 6000rpm and the displacement to 350 plus inches the runners are a huge restriction, theres little wrong with the basic intake design as its only directing air, the fuels added at the head ports, its the cross sectional area that's the problem, the first and a couple other choices, in intakes solve the restriction in different ways, (shorter, or larger runners in most cases)

READ THIS
viewtopic.php?f=55&t=2614

 

[grumpyvette]

stealthram base

you may be amazed to find a great deal of research and testing has been done and theres actually proven facts rather than random guess work to use in planing a well built engine combo

stock un-ported runner entrances
the very minor issue here is simply that you won,t have a valid before & after dyno result to compare between the two, intake manifold prep levels,if you install a modified and cleaned-up improved intake manifold without first using a stock as cast version,
thus you won,t have the ability to truly feel , or see on a dyno the DIFFERENCE,
your effort to increased efficiency had, on those improvements to the air flow rates, or the real measurable effect that had , had on the engine.
but I can assure you there is a measurable improvement , simply from similar pass intake port work.
Ive regularly seen power increases in the 15-20 hp range with similar work you've displayed,
but I know that gains in power from similar port & runner clean-up work, of over 25-30 hp are rather common.

porting helps flow significantly
JUST A NOTE, in my experience,if your into building a TPI the secret is in matched components and use of great heads, find heads that flow a MINIMUM of 250cfm at .500 lift, use a 10:1-10.5:1 cpr 36-42 lb injectors
A PROPERLY PORTED AND MODIFIED STEALTH RAM INTAKE, or a FIRST TPI CLONE INTAKE with a hydraulic roller cam similar to a CROWER 00471 or CRANE 119691, 1.6:1 roller rockers, and a 3.73:1 rear gear, manual transmission or 3000rpm-3400rpm stall converter low restriction headers and a 383-406 displacement wil leasily exceeds these numbers
KEEP IN MIND the longer runners on the FIRST TPI clone intake design will produce a bit better low and mid rpm torque and start to become restrictive at about 600-800rpm lower than the properly ported STEALTH-RAM, but displacement, cam selected and heads used will have a big effect on results either intake matched to the correct engine,components like listed above
easily exceeds these numbers, but if you don,t use ALL the listed steps it wont work up to potential

related info
viewtopic.php?f=55&t=1509&p=3459&hilit=runner+porting#p3459

related info

viewtopic.php?f=52&t=3802&p=18031&hilit=119591#p18031

KEEP IN MIND THERE ARE OTHER SOURCES FOR HIGH FLOW TPI STYLE BASES, LIKE THE FIRST TPI CLONE
RUNNERS AND BASE SHOWN BELOW,THAT WILL FIT UNDER A STOCK CORVETTE HOOD UNLIKE THE STOCK STEALTH RAM, but without the matching high flow cylinder heads, good roller cam, matched compression, increased displacement, low restriction exhaust and headers, and gearing your never going to get near full power potential
http://www.firstfuelinjection.com

Came across this info while doing some research and thought I'd share.

http://www.hobracing.com/tech/tpi_flow.asp
TPI Intakes and runners

The following airflow tests were performed on the University of Northwestern Ohio's SuperFlow SF600 Flow Bench. All CFM values are corrected for airflow at 28 inches of water. Injector flow rates are flowed at 43.5 PSI on an injector flow bench using test fluid with same density as gasoline.

AirFlow

Stock TPI/LT1 48mm Throttle Body w/o airfoil -- 783.0 cfm

Stock TPI/LT1 48mm Throttle Body w/ airfoil -- 821.9 cfm

TPI/LT1 52mm Throttle Body w/o airfoil -- 848.9 cfm

TPI/LT1 52mm Throttle Body w/ airfoil -- 898.8 cfm

Stock 98 Camaro 3800 II Throttle Body -- 554.3 cfm

Stock TPI Bosch MAF sensor w/ screens -- 517.8 cfm

Stock TPI Bosch MAF sensor w/o screens -- 658.4 cfm

Stock 87 GN 3.8L Turbo AC MAF sensor w/ screen -- 584.2 cfm

Stock 86 2.8L AC 5-wire MAF sensor w/ screen -- 576.2 cfm

Stock 96-up AC 3100 V6 MAF sensor w/ screen -- 616.4 cfm

Stock 96-up AC 3100 V6 MAF sensor w/o screen -- 670.7 cfm

Stock 94-up LT1 MAF Sensor w/o screen -- 719.0 cfm

Stock 85-87 Firebird TPI airbox mid piece -- 499.3 cfm

Stock 4.3/5.0/5.7 2bbl TBI complete -- 574.1 cfm (dry)

Stock 4.3/5.0/5.7 2bbl TBI w/o injectors -- 584.7 cfm

Stock 3800 vin L throttle body w/ screen -- 419.1 cfm

Stock 3800 vin L throttle body w/o screen -- 444.8 cfm

4bbl MPFI Holley Throttle Body -- 1287.6 cfm

Another source sent in these flow numbers

Flow and HP ratings for Throttle-bodies:

Flow (cfm) Max. NA HP
Stock 668 300
Stock w/airfoil 710 350
52MM w/airfoil 835 400
54MM (AS&M) 900 450
58MM 1050 500


TPI Intakes and runners flow rates

Stock intake manifold with runner
Stock....................198.72 cfm
ACCEL................213.52 cfm
Extrude/ACCEL....217.11 cfm
Super Ram............220.67 cfm

the stock TPI has a hard time flowing 230cfm even with minor port work, look here
most of this info is right off the accel,holley,edelbrock, and TPIS sites, add a little math and the results become much clearer!!!

Intake....... length ....... port in -- out
Stock GM Base--- 6.375"------ 1.47"- 1.96x1.2
TPiS base------ -6.125"------ 1.75"- 2.09x1.28
Accel base----- -6.125"------ 1.75"- 2.09x1.28
Holley base------- 6” runner 2.3”- 1.9”x 1.23 (2.337 sq inches)
Runners
Stock TPI----- -- 7.250"------1.470" round(1.70 sq inchs)
SLP ----------- - 6.625"------1.600" round (2.01 sq inchs)
Accel LTR------- 6.625"------1.615" round (2.05 sq inchs)
TPiS----------- 7.625"------1.660" round (2.168 sq inchs)
Mini ram -----3.5”
LT1 ----------3”

Runners (measured individually)
Stock....................203.17 cfm
ACCEL................242.02 cfm
Extrude/ACCEL...275.83 cfm
Super Ram............289.18 cfm
Intake manifold with 3/8 inch radiused intlet.............................222.45 cfm
Holley stealth ram ………..275cfm

Stock intake manifold with runner
Stock....................198.72 cfm
ACCEL................213.52 cfm
Extrude/ACCEL....217.11 cfm
Super Ram............220.67 cfm
Holley stealth ram …..275cfm

ACCEL Hi-Flow intake manifold with 3/8 inch radiused inlet.........251.51 cfm

ACCEL Hi-Flow intake manifold with runner
Stock....................215.83 cfm
ACCEL................232.53 cfm
Extrude/ACCEL....243.21 cfm
Super Ram............240.24 cfm

Extrude-Honed ACCEL Hi-Flow intake manifold with 3/8 inch radiused inlet ...............275.83 cfm
Extrude-Honed ACCEL Hi-Flow intake manifold with ACCEL runner ..............266.94 cfm
Edelbrock Performer RPM manifold (Stock)..........286.51 cfm
Edelbrock Victor Jr. ............275.24 cfm

HOLLEY STEALTH RAM
the HOLLEY STEALTH RAM FLOWS at 275cfm out of the box, and has the potential when matched to the correct heads and cam to totally out flow most other intakes available,can easily reach 300cfm with minor port work and costs much less
Stock…………………………… 275cfm
Ported…………………………..300cfm

Runner lengths
Stock tpi manifold 8” runners 11.25”, cylinder head 6” total 25.25”
Accel super ram manifold 8” runners 7” cylinder head 6” total 21”
Holley stealth ram manifold 6.26” ” cylinder head 6” total 12.26”
Edelbrock performer RPM runners 6” ” cylinder head 6” total 12”
Edelbrock vic jr , runner length 5.5” ” ” cylinder head 6” total 11.5”



Also interesting TPI mods. Not so sure I agree with the one on bumping up the initial timing.
http://www.hobracing.com/tech/tpi_mods.asp


Basic TPI modifications
Friday, May 23, 2014





Basic TPI Mods: by DEBBIES87

There are a few basic mods that should be done to any TPI car, I call these "entry-level" modifications.

1) Cut the air box open without letting air in the engine without going through the air filter & remove the additional plastic piece below the air box to get more air into the engine.

2) Modify the mass air sensor; remove the screens, & and if your brave cut down the fins.

3) Port the plenum (upper intake). There are two small ridges sticking up in the entry-behind the throttle body, remove these. The throttle body openings are already 52mm, so don't go crazy when porting.

4) While the plenum is off for porting, it is now a good time to get a adjustable fuel pressure regulator & a MAT sensor relocater kit. The Adj. FPR will aid in tuning, and the new MAT sensor will improve throttle response as well. The new LT1 style MAT sensor is placed in the air box instead of the plenum, this allows it to read cooler air and advance the timing accordingly.

5) Advance the base timing to 12-13 degrees. Note: the harmonic balancers on these cars tend to drift with age, adjust timing to where the car still starts good and doesn't detonate.

6) If legal in your area, gut the catalytic converter and remove the smog pump belt (85-87), or run a shorter serpentine belt to bypass the pump (88-92); you will need to remove the smog pump on the 88-92's to reroute the belt properly. Check local smog laws first.

7) On automatic cars, adjust T.V. cable (throttle valve cable), so that the car shifts out between 4200-4500 RPM under wide open throttle. TPI motor power drops off drastically after 4500-4700 RPM, they peak at about 4200-4400 RPM. No need to over-rev these motors.

8) Bypass fan relay to make fans come on manually, or install aftermarket relay to turn on fans sooner.

All together these mods should make the car perform like it should have from the factory, gains should be between .6-.9 tenths of a second from these modifications.




T.V

SOURCES FOR GOOD AFTERMARKET HEADS
http://www.profilerperformance.com/racing/cylinderheads/sbc-23-degree

http://www.airflowresearch.com/index.php?cPath=24_29

“While I’m this far….?”

I must have said this to myself daily for the past few months & I end up going deeper into my corvette engine. So I need some advice on what I should &/or perhaps not do. My vette is an 89 w/around 72k miles on her. I finally decided to pull her from close to a decade of hibernation to...

garage.grumpysperformance.com

http://www.jegs.com/i/Brodix/158/102100 ... tId=760699

http://www.jegs.com/i/Dart/301/127422/10002/-1?parentProductId=1691309

 

[grumpyvette]

IF YOU HAVE AN EARLIER STEALTH RAM WIRE HARNESS

There was an error on the IAC pinout on Stealthram/TPI harnesses shipped up until 7-12-10 on Holley HP or Dominator systems.

This will cause improper IAC functionality.

Can be fixed by moving the wires at the IAC connector (requires a Weatherpack pin removal tool) OR the ECU connectors (requires no special tools, can be done by hand). Both methods are shown below.


Fix 1) Changing pins at IAC connector (requires Weatherpack pin removal tool.


Remove wires from the IAC connector with a Weatherpack pin removal tool. Swap the wires to the following locations on the IAC connector:

IAC Connector Wire Color
A Purple/Yellow
B Purple/Blue
C Purple/Black
D Purple/White


OR


Fix 2) Changing IAC pins at ECU – Does not require special tools

1) Removes the wires out of the following Pins on the smaller 26 pin ECU connector:
- Pin B1 (Purple/Blue)
- Pin B2 (Purple/Yellow)
- Pin B8 (Purple/White)
- Pin B9 (Purple/Black)

To remove the wires, take a small flat-blade screwdriver or something with a small tip (ballpoint pen) and push on the single white clip on the bottom of the smaller 26 pin harness connector. The clip should push inward. Pull the four IAC wires out of the back of the connector. Be careful that you don’t pull other wires partially out of the connector when removing the wires.



2) Reinstall them as follows:
- Purple/Black = Pin B1
- Purple/Blue = Pin B2
- Purple/Yellow = Pin B8
- Purple/White = Pin B9

Make sure they are inserted fully. Look at the front of the connector and you should be able to see the silver end of the pins.

Once all pins are fully re-inserted, push the double white retaining clips on the opposite side of the connector back in. If the retaining clip does not go back in, it is likely that some pins are not fully seated. Look at the front of the connector for pins that are recessed back on the connector.
Doug