Quest for a better flowing TPI
#101
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Car: 1990 G92 IROC Z Miniram
Engine: 388cu 6.4 Liters
Transmission: G-Force T5
Axle/Gears: 3.73 Gears
Re: Our quest for a better flowing TPI
I heard a simeased Super Ram lost power and torque. Those simeased runners had help making power with the manifold being the main reason for the higher horsepower. The manifold has metal added and reshaped to flow over 310cfms vs an Extrude Manifold that flows 261 cfms. If you notice you don't see most Dynos Runs with a Super Ram make power up to 5800 without falling off. Most fall off around 5200 to 5400.
#102
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Re: Our quest for a better flowing TPI
wow and people dont understand why i swapped from tpi to carbed...im gonna swap to an edelbrock fuel injection setup sooner or later. not trying to be a ****, looks like yall have alot of time invested in this looking good so far maybe when yall figure it all out ill switch back to tpi....so keep up the good work...
#104
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Car: '88 Camaro
Engine: 5.7 L98
Transmission: 700R4
Axle/Gears: Borg Warner 9 bolt w/3.27 lim. slip
Re: Our quest for a better flowing TPI
Are any of these cars 6.3 or are they all 5.7's? How did "comp cams" get there TPI's around 410?
http://www.compcams.com/Community/Ar...?ID=1737510521
http://www.compcams.com/Community/Ar...?ID=1737510521
#105
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Re: Our quest for a better flowing TPI
You're looking at a bunch of 5.7's.
That link you posted, those are flywheel HP numbers, not rear wheel HP numbers. Who knows what other items are missing like smog controls *cough* AIR *cough*, power steering, alternator... Oh and I'm sure they had a cat attached to those headers.
That link you posted, those are flywheel HP numbers, not rear wheel HP numbers. Who knows what other items are missing like smog controls *cough* AIR *cough*, power steering, alternator... Oh and I'm sure they had a cat attached to those headers.
#107
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Car: 90 IROC
Engine: 406
Transmission: GMPP 93/4L60
Axle/Gears: 9 bolt 3.27
Re: Our quest for a better flowing TPI
I heard a simeased Super Ram lost power and torque. Those simeased runners had help making power with the manifold being the main reason for the higher horsepower. The manifold has metal added and reshaped to flow over 310cfms vs an Extrude Manifold that flows 261 cfms. If you notice you don't see most Dynos Runs with a Super Ram make power up to 5800 without falling off. Most fall off around 5200 to 5400.
#108
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Re: Our quest for a better flowing TPI
Yes the base was the same between the Super Ram and the modified TPI setup. It was the one that flowed well past 300cfm and used for both tests. The runners on the Super Ram have been Extrude Honed. The only thing that was switched were the runners and the plenums.
Thank you Kevin and Vincent for taking the time to do the test. Not often do you see a back to back test like this.
Thank you Kevin and Vincent for taking the time to do the test. Not often do you see a back to back test like this.
#109
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Car: 90 IROC
Engine: 406
Transmission: GMPP 93/4L60
Axle/Gears: 9 bolt 3.27
Re: Our quest for a better flowing TPI
Allen... thanks for clearing that up for me. After reading vincents post again i understand what he was saying. Sorry to hear about your driveshaft good thing it didnt happen while the car was moving. A safety loop would be on your list of things to do im sure.
And yes the base is the key even though its a 350 i still havent seen many superrams with that much topend. With my 400 opening the base up like you guys have done is a must do.
Would a machine shop be able to handle the welding? Not sure what type of place to go for this service. Any advise where to go?
And yes the base is the key even though its a 350 i still havent seen many superrams with that much topend. With my 400 opening the base up like you guys have done is a must do.
Would a machine shop be able to handle the welding? Not sure what type of place to go for this service. Any advise where to go?
#110
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Re: Our quest for a better flowing TPI
Any place that can weld aluminum. I would think a welding shop for sure. Maybe a machine shop if they also do welding. The reason for the welding on top is twofold. One to get more cross sectional area and two to arch the roof of the port for a better entry into the head.
#111
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Re: Our quest for a better flowing TPI
Now we just need someone to send us a StealthRam so we can test that. I might have a set of aftermarket long tube runners to test, as well. But its probably not worth it since these were all tested in that article in the sticky post.
#112
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Car: '91 Z28 L98 G92
Engine: Modded L98
Transmission: Modded 700R4
Axle/Gears: Modded 10-Bolt
Re: Our quest for a better flowing TPI
Bill
#113
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Car: '88 Camaro
Engine: 5.7 L98
Transmission: 700R4
Axle/Gears: Borg Warner 9 bolt w/3.27 lim. slip
Re: Our quest for a better flowing TPI
What kind of difference would you expect from a 5.7 with a 400 crank(6.3)?
#114
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Car: 1988 IROC-Z28
Engine: L98(383tpi) modified
Transmission: 700R4 rebuilt
Axle/Gears: 3:73 10bolt rebuilt
Re: Our quest for a better flowing TPI
Hey guys iv'e been reading your posts for awhile and I would like to know what would be a reconmended max. rpm for my IROC with my setup?
Engine:
383 L98 TPI, 350 bored .030 over truck block 4 bolt main honed and magnafluxed
Engine Modifications:
Stock plenum ported/simeased for the runners and throttle body
Edelbrock intake manifold and runners ported and simesed
Edelbrock Performer heads 64cc & 160/202 intake/exhaust
Edelbrock Valve Covers
Moroso valve cover breathers
Edelbrock 58mm Throttle Body
Racetronix 37lb. Injectors
Walbro high performance fuel pump
Holley adj. fuel pressure regulator
Manly Pushrods
Crane 1.6 Roller Rockers
Comp cam Hydraulic roller:
510/540 gross lift 1.6 rockers bump up lift to 576
Duration at .050 intake:230/exhaust244
Lobe separation:112
Keith Black hypereutectic 10:5: 1 pistons
Chrome Molly rings
Scat forged piston rods
refurbished truck 400 crank turned down
Cat harmonic balancer
Moroso 6qt. Pan
Edelbrock water pump
MSD HEI distributor with cap & rotor
MSD Blaster coil
MSD box 6AL with rev. limiter
Accel 8.8 wires with heat retarded sleeves
Bosch platinum plugs
Hooker long tube coated headers 1 3/4
Mufflex 3.0" Cat Back Exhaust System
3” Flowmaster Race Series muffler Cat-back
SLP cold air induction
K/N air filter
Grantanelli adj. Mas air flow sensor
Under drive pulleys
Modified custom serpentine belt system
Transmission:
Re-Built 700R-4 Trans
Transmission Modifications:
B&M Ratchet Shifter
B&M shift kit
B&M 3000 stall
Corvette servo
B&M Trick Shift fluid
B&M large capacity trans pan
B&M trans cooler
Transmission tunnel mounted torque arm w/ DS loop
Chassis:
Comp. Engineering sub-frame conn.
Brakes:
Stock brakes
Crane vaccum boost
Front cross drilled/sloted rotors
Hawk pads
Earls braided lines
Suspension:
Lakewood drag shocks
Mack LCA’s
Mack Panhard bar
Mack torque arm
IROC wonder bar
Axle:
Re-Built 10 bolt rear end with 3.73’s and T/A girdle
Wheels:
16" IROC rims polished and powdered coated
Tires:
Future Mods: Drag Radials
Exterior:
Custom paint; Chevy Orange
Interior:
Jegs racing seats
5 point belt harness
B&M floor shifter
2 gauge Pod pillar
(Autometer trans & water temp.)
No rear seats
Audio:
Pioneer with amp Jenson speakers
future Mods:
Nitrous
C4 front brake upgrade
Subs in the trunk
Miscellaneous:
Custom chip: Fast Chip Performance
3 core radiator
Water Wetter with 50/50 mixture
180 dergree thermostat
Hayden electric high flow cooling fan
PowerMaster High torque Starter re-build
PowerMaster Alternator
Optima Battery
Pennzoil 20/50
NO SMOG EQUIPTMENT:
Such as;
No cats
No egr
No smog pump
Etc.
----------
Sorry for the long post!
Engine:
383 L98 TPI, 350 bored .030 over truck block 4 bolt main honed and magnafluxed
Engine Modifications:
Stock plenum ported/simeased for the runners and throttle body
Edelbrock intake manifold and runners ported and simesed
Edelbrock Performer heads 64cc & 160/202 intake/exhaust
Edelbrock Valve Covers
Moroso valve cover breathers
Edelbrock 58mm Throttle Body
Racetronix 37lb. Injectors
Walbro high performance fuel pump
Holley adj. fuel pressure regulator
Manly Pushrods
Crane 1.6 Roller Rockers
Comp cam Hydraulic roller:
510/540 gross lift 1.6 rockers bump up lift to 576
Duration at .050 intake:230/exhaust244
Lobe separation:112
Keith Black hypereutectic 10:5: 1 pistons
Chrome Molly rings
Scat forged piston rods
refurbished truck 400 crank turned down
Cat harmonic balancer
Moroso 6qt. Pan
Edelbrock water pump
MSD HEI distributor with cap & rotor
MSD Blaster coil
MSD box 6AL with rev. limiter
Accel 8.8 wires with heat retarded sleeves
Bosch platinum plugs
Hooker long tube coated headers 1 3/4
Mufflex 3.0" Cat Back Exhaust System
3” Flowmaster Race Series muffler Cat-back
SLP cold air induction
K/N air filter
Grantanelli adj. Mas air flow sensor
Under drive pulleys
Modified custom serpentine belt system
Transmission:
Re-Built 700R-4 Trans
Transmission Modifications:
B&M Ratchet Shifter
B&M shift kit
B&M 3000 stall
Corvette servo
B&M Trick Shift fluid
B&M large capacity trans pan
B&M trans cooler
Transmission tunnel mounted torque arm w/ DS loop
Chassis:
Comp. Engineering sub-frame conn.
Brakes:
Stock brakes
Crane vaccum boost
Front cross drilled/sloted rotors
Hawk pads
Earls braided lines
Suspension:
Lakewood drag shocks
Mack LCA’s
Mack Panhard bar
Mack torque arm
IROC wonder bar
Axle:
Re-Built 10 bolt rear end with 3.73’s and T/A girdle
Wheels:
16" IROC rims polished and powdered coated
Tires:
Future Mods: Drag Radials
Exterior:
Custom paint; Chevy Orange
Interior:
Jegs racing seats
5 point belt harness
B&M floor shifter
2 gauge Pod pillar
(Autometer trans & water temp.)
No rear seats
Audio:
Pioneer with amp Jenson speakers
future Mods:
Nitrous
C4 front brake upgrade
Subs in the trunk
Miscellaneous:
Custom chip: Fast Chip Performance
3 core radiator
Water Wetter with 50/50 mixture
180 dergree thermostat
Hayden electric high flow cooling fan
PowerMaster High torque Starter re-build
PowerMaster Alternator
Optima Battery
Pennzoil 20/50
NO SMOG EQUIPTMENT:
Such as;
No cats
No egr
No smog pump
Etc.
----------
Sorry for the long post!
Last edited by Americanmouse; 03-27-2008 at 12:33 PM. Reason: Automerged Doublepost
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Bmassa75 (10-13-2022)
#115
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Re: Our quest for a better flowing TPI
I'd also be curious as to what the Stealth ram would do compared to your modded TPI and superam setups. I have a feeling it will surpass both by a good number based on a few results i've seen.
Americanmouse, your 383 should peak around 4800-5000 unless its ported out alot and siamesed alot. MAYBE 5200 but i doubt it with those large cubes. On the side note, did you ever run that car before at the track?
Americanmouse, your 383 should peak around 4800-5000 unless its ported out alot and siamesed alot. MAYBE 5200 but i doubt it with those large cubes. On the side note, did you ever run that car before at the track?
#116
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Car: 1988 IROC-Z28
Engine: L98(383tpi) modified
Transmission: 700R4 rebuilt
Axle/Gears: 3:73 10bolt rebuilt
Re: Our quest for a better flowing TPI
Thanks for the reply!
I never took it to the track.
Also I did some major gutting out in the intake manifold,runners, and plenum.
I also thought that the stock T.P.I.'S run at 4800, and yet your saying I should be running 4800 to 5200!? Even with the heavy mods I have done!
I'm confused!!!
I never took it to the track.
Also I did some major gutting out in the intake manifold,runners, and plenum.
I also thought that the stock T.P.I.'S run at 4800, and yet your saying I should be running 4800 to 5200!? Even with the heavy mods I have done!
I'm confused!!!
#117
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Re: Our quest for a better flowing TPI
Look at these guys' results. There extremely modded TPI setups are peaking at 5500 and carrying to near 6000, some abit more but most of them will peak at 5500. Thats a seriously modded runner system and base. Also they have much better heads than those edelbrocks you have.
If you have done the same mods to the base/runners as they have done, then yours will peak just a tad lower since the 383 requires even more airflow to satisfy it. 5200 rpms peak from a 383 TPI is pretty darn good. your cam has ability to peak near 6000, but the heads/intake i dont think will support it much over 5200 rpms or so.
If you have done the same mods to the base/runners as they have done, then yours will peak just a tad lower since the 383 requires even more airflow to satisfy it. 5200 rpms peak from a 383 TPI is pretty darn good. your cam has ability to peak near 6000, but the heads/intake i dont think will support it much over 5200 rpms or so.
#118
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Car: 86 vette
Engine: 383
Transmission: 700R4
Axle/Gears: 3.07
Re: Our quest for a better flowing TPI
Everything happens at a lower rpm because of more air flow.
The dynamics are different because it is all stroke increase, as opposed to bigger bore. It pulls same air (bore) for a longer time (stroke). 1/4" stroke difference means 1/2" total (1/4" tdc and 1/4" bdc).
#119
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Car: 1990 G92 IROC Z Miniram
Engine: 388cu 6.4 Liters
Transmission: G-Force T5
Axle/Gears: 3.73 Gears
Re: Our quest for a better flowing TPI
Yea! But the article did not test it with a modded manifold. This is one way to find out if the manifold is the main restriction. I'll pay half of the dyno time if you like.
Last edited by VincentZ28; 03-27-2008 at 08:42 PM.
#120
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Car: 1990 G92 IROC Z Miniram
Engine: 388cu 6.4 Liters
Transmission: G-Force T5
Axle/Gears: 3.73 Gears
Re: Our quest for a better flowing TPI
[QUOTE] We saw a simular set up except it was a 406cu with a Comp Cams 280XFI an AFR heads, 5 speed, Super ram with a 58mm TB an Edelbrock manifold(not ported) made 386rwhp@5500-434rwtq@4400.
Your set up might be around 340-355hp@5200 and 390-415tq@4400 because you have smaller flowing heads. 37lbs injectors is way to much. The most you would need is 30lbs.
Hey guys iv'e been reading your posts for awhile and I would like to know what would be a reconmended max. rpm for my IROC with my setup?
Engine:
383 L98 TPI, 350 bored .030 over truck block 4 bolt main honed and magnafluxed
Engine Modifications:
Stock plenum ported/simeased for the runners and throttle body
Edelbrock intake manifold and runners ported and simesed
Edelbrock Performer heads 64cc & 160/202 intake/exhaust
Edelbrock Valve Covers
Moroso valve cover breathers
Edelbrock 58mm Throttle Body
Racetronix 37lb. Injectors
Walbro high performance fuel pump
Holley adj. fuel pressure regulator
Manly Pushrods
Crane 1.6 Roller Rockers
Comp cam Hydraulic roller:
510/540 gross lift 1.6 rockers bump up lift to 576
Duration at .050 intake:230/exhaust244
Lobe separation:112
Keith Black hypereutectic 10:5: 1 pistons
Chrome Molly rings
Scat forged piston rods
QUOTE]
Engine:
383 L98 TPI, 350 bored .030 over truck block 4 bolt main honed and magnafluxed
Engine Modifications:
Stock plenum ported/simeased for the runners and throttle body
Edelbrock intake manifold and runners ported and simesed
Edelbrock Performer heads 64cc & 160/202 intake/exhaust
Edelbrock Valve Covers
Moroso valve cover breathers
Edelbrock 58mm Throttle Body
Racetronix 37lb. Injectors
Walbro high performance fuel pump
Holley adj. fuel pressure regulator
Manly Pushrods
Crane 1.6 Roller Rockers
Comp cam Hydraulic roller:
510/540 gross lift 1.6 rockers bump up lift to 576
Duration at .050 intake:230/exhaust244
Lobe separation:112
Keith Black hypereutectic 10:5: 1 pistons
Chrome Molly rings
Scat forged piston rods
QUOTE]
Your set up might be around 340-355hp@5200 and 390-415tq@4400 because you have smaller flowing heads. 37lbs injectors is way to much. The most you would need is 30lbs.
Last edited by VincentZ28; 03-27-2008 at 11:00 PM.
#123
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Car: 1988 IROC-Z28
Engine: L98(383tpi) modified
Transmission: 700R4 rebuilt
Axle/Gears: 3:73 10bolt rebuilt
Re: Our quest for a better flowing TPI
[QUOTE=VincentZ28;3694842]
We saw a simular set up except it was a 406cu with a Comp Cams 280XFI an AFR heads, 5 speed, Super ram with a 58mm TB an Edelbrock manifold(not ported) made 386rwhp@5500-434rwtq@4400.
Your set up might be around 340-355hp@5200 and 390-415tq because you have smaller flowing heads. 37lbs injectors is way to much. The most you would need is 30lbs. Ok! are these rwhp/rwt for my IROC or at the fly?
As far as my heads go I was told after having several valves and springs replaced last year due to retarding my cam to far "duh" that my heads flowed very well, and he said if I did any more modification to them would greatly affect daily driving. This is coming from a Cylinder Head shop owner who builds race engines.
I went to 37lb. injectors for any future upgrades such as nitrious.
And thanks again for all your replys.
As far as my original question goes I had a custom chip done in 05'. Since then I have done additional mods. That requires a new chip which they said could be done for a little up grade fee. I know alot of you frown on that, but I don't have the time or patience to play with Tuner Pro, ACCEL, etc.
We saw a simular set up except it was a 406cu with a Comp Cams 280XFI an AFR heads, 5 speed, Super ram with a 58mm TB an Edelbrock manifold(not ported) made 386rwhp@5500-434rwtq@4400.
Your set up might be around 340-355hp@5200 and 390-415tq because you have smaller flowing heads. 37lbs injectors is way to much. The most you would need is 30lbs.
As far as my heads go I was told after having several valves and springs replaced last year due to retarding my cam to far "duh" that my heads flowed very well, and he said if I did any more modification to them would greatly affect daily driving. This is coming from a Cylinder Head shop owner who builds race engines.
I went to 37lb. injectors for any future upgrades such as nitrious.
And thanks again for all your replys.
As far as my original question goes I had a custom chip done in 05'. Since then I have done additional mods. That requires a new chip which they said could be done for a little up grade fee. I know alot of you frown on that, but I don't have the time or patience to play with Tuner Pro, ACCEL, etc.
#126
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Car: '91 Z28 L98 G92
Engine: Modded L98
Transmission: Modded 700R4
Axle/Gears: Modded 10-Bolt
Re: Our quest for a better flowing TPI
Bill
----------
If I have a 355" or 383" short-block built, then I will go bigger on the cam.
Bill
Last edited by Burnout91; 03-28-2008 at 07:36 AM. Reason: Automerged Doublepost
#128
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Car: '91 Z28 L98 G92
Engine: Modded L98
Transmission: Modded 700R4
Axle/Gears: Modded 10-Bolt
Re: Our quest for a better flowing TPI
Bill
Last edited by Burnout91; 03-28-2008 at 03:43 PM.
#129
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Re: Our quest for a better flowing TPI
i think it wil hold it for awhile. Shifting at 6K isnt bad, its going much above that it becomes a problem I had a buddy shifting a Lt1 intaked L98 with a cc306 cam at 6000 ish rpms for awhile. car touched 11.90's with stock heads.
But even the 268 cam should make peak power somewhere in the 5800 rpms range. May shift that one at 6000 as well. Either way i think you will like both cams. Nothing wrong with slighly short shifting the bigger cam if its making more hp at the shift point than the smaller. I think the hot ticket would be the 224/230 xfi version. Comp has the lobes, they just dont offer it off the shelf. they could make it for you for the same price tho.
But even the 268 cam should make peak power somewhere in the 5800 rpms range. May shift that one at 6000 as well. Either way i think you will like both cams. Nothing wrong with slighly short shifting the bigger cam if its making more hp at the shift point than the smaller. I think the hot ticket would be the 224/230 xfi version. Comp has the lobes, they just dont offer it off the shelf. they could make it for you for the same price tho.
#130
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Car: clapped out 84Z
Engine: 355 efi roller
Transmission: tremec TKO
Re: Our quest for a better flowing TPI
I also have to agree with this.
My thoughts on the outcome:
-probably a couple hp more with a carb setup
-probably peak around the same rpm
I think the limiting factor is the heads, followed by the cam.
From my personal experience when trying to make big #'s and spinning a 350 past 6K.
I went from a set of home ported 200cc dart sportsmans to a set of competition AFR 195's (flow 280 something on the intake) and a rev kit.
With only a head change, my hp peak went from just around 5900 to 6200-6300, torque peak was the same, and peak rwhp increased by about 60. And I spun it up to 6700-6800 and it only dropped off 10-15 hp from the peak (like an LS1 and probably b/c of the rev kit). With the sportsmans it fell off a cliff at 6300. I'm running a comp hydraulic roller 230/236 on a 110, 106 CL 544/555 lift with 1.6 rockers and a pro-ram.
Great thread to read and two thumbs up to all of you and your methodical approach and efforts.
#132
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Car: 1988 IROC-Z28
Engine: L98(383tpi) modified
Transmission: 700R4 rebuilt
Axle/Gears: 3:73 10bolt rebuilt
Re: Our quest for a better flowing TPI
Well after doing a little reseach, I'm amazed at the numbers on the AFR heads to my Edelbrock. With that being said Would it be best for me to get my heads re-worked especially to save money. Or get say the AFR'S 195. I don't care about emissions since my IROC is now under show car insurance, which means its emission exempt.
#134
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Car: 1988 IROC-Z28
Engine: L98(383tpi) modified
Transmission: 700R4 rebuilt
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Re: Our quest for a better flowing TPI
I'm going to make a couple calls and see what could be done to my heads. I think it would a lot cheaper and they may be able to come close to the numbers that the AFR'S make. Which would be fine for me!
#137
Re: Our quest for a better flowing TPI
for the guys running a hsr? besides maybe a port match to a 1205 gasket are you guys runnig these things with no other porting work inside the intake ,i mean where the top plenum meets the base with the 8 d shaped ports i just got my hsr and noticed these d shape ports r freakin tiny and inconsistant between the 8 d ports this thing looks like it would choke up a 305 not to mention the manifold ports measured smaller than a 1204 gasket they just look like they need alot of work to flow enuff for 383ci one more thing has anyone wondered why the injector bosses are like a half inch higher than the stock base? if u put an injector in it then flip the intake over the injector end tip is way up in the hole like a half inch it looks like you wont get a good spray pattern because of this on a stock int or my tpis bigmouth int the injector tip sits closer to flush with the port roof , looks like it would spray better into the cyl head port better. i know i should have started a new thread for this but i wanted the top dogs in here to read this like orr 89 roc and his friends i know you guys are very good with tpi because ive been lurkin 4 a long time sorry if i bothered any body an thanks
#138
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Re: Our quest for a better flowing TPI
HSR ports do look small, but they do flow 275cfm out the box. I opened up my intake alittle to better match my AFR heads and to gain more flow for my 383 even tho its probly not necessary. There are guys making near 400whp with somewhat smaller cams with HSR out the box, so its capable of doing a good job as is.
thats one reason i would like to see their motors dyno'd with a HSR for comparison purposes. HSR may flow less than their ported TPI stuff, and the effective runner length may be the same or close to it, but the shape of the runners are different. So lets see if the runner shape effects the airflow. If the HSR makes more power even tho it flows less, then TPI runner shape is not optimal for power.
thats one reason i would like to see their motors dyno'd with a HSR for comparison purposes. HSR may flow less than their ported TPI stuff, and the effective runner length may be the same or close to it, but the shape of the runners are different. So lets see if the runner shape effects the airflow. If the HSR makes more power even tho it flows less, then TPI runner shape is not optimal for power.
#139
Re: Our quest for a better flowing TPI
thanks orr
ya i read a thread between sofa kingdom an another guy an sofa was sayin the hsr cant flow 275 cfm ,he said those numbers came from stealthram .com an enthusiast site not a real test sie or whatever he said they were. has any1 on tgo ever flowed a hsr that u know of? if it really flows 275 cfm thats plenty. sofa an this guy got really heated he made some good points . any i just started cleanig the d shapes up a little bit tryin to straighten out the the bends an stuff just tryin to get more of a straight shot to the cyl head port some of the ports are quite a bit smaller than others thanks for listening later , keith
ya i read a thread between sofa kingdom an another guy an sofa was sayin the hsr cant flow 275 cfm ,he said those numbers came from stealthram .com an enthusiast site not a real test sie or whatever he said they were. has any1 on tgo ever flowed a hsr that u know of? if it really flows 275 cfm thats plenty. sofa an this guy got really heated he made some good points . any i just started cleanig the d shapes up a little bit tryin to straighten out the the bends an stuff just tryin to get more of a straight shot to the cyl head port some of the ports are quite a bit smaller than others thanks for listening later , keith
#140
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Re: Our quest for a better flowing TPI
Sounds like you are on the right track with making the ports the same.
Regarding the moded TPI's. With my next trip to the dyno we will find out if it is the exhuast that is holding us back somewhat. We have test pipes to remove the catalytic converters on the dyno and see what that does. By the way all the repairs have been made and a new aluminum 3" drive shaft is now in place. We are ready for the next dyno session.
I just don't see where the restriction is on the intake system. If you consider that I have 4 mini plenums feeding two runners each than it is almost a straight shot into the heads. Not quite as straight as an HSR though or as short.
Regarding the moded TPI's. With my next trip to the dyno we will find out if it is the exhuast that is holding us back somewhat. We have test pipes to remove the catalytic converters on the dyno and see what that does. By the way all the repairs have been made and a new aluminum 3" drive shaft is now in place. We are ready for the next dyno session.
I just don't see where the restriction is on the intake system. If you consider that I have 4 mini plenums feeding two runners each than it is almost a straight shot into the heads. Not quite as straight as an HSR though or as short.
#141
Re: Our quest for a better flowing TPI
ya 89 gta ive been following this thread since the beginning i hope the exhaust change helps you out lookin forward to seein ur numbers imo a hsr cant keep up with a fully modded stock tpi like yours but will see . i wish i had a flow bench so bad lol. i read that article in super rod an the hsr number seems high for what my ports look like on my hsr
#143
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Re: Our quest for a better flowing TPI
any i just started cleanig the d shapes up a little bit tryin to straighten out the the bends an stuff just tryin to get more of a straight shot to the cyl head port some of the ports are quite a bit smaller than others thanks for listening later , keith
Reguarding the advertised 275cfm, that may be correct that it may not flow that much. I have NO idea. I havent seen any other test results either. If you read about the hSR in some earlier threads you will find many haters saying its not a performance manifold, and to some extent its not really the best design for all out performance. BUT that doesnt mean its not capable of putting down respectable numbers
I have seen AFR headed 383 dyno sheets with HSR putting down near 380 whp thru an auto with the LT4 hotcam which is a mild cam. I have also seen some so/so dyno figures for this manifold. I am hoping to crest the 400whp mark if not exceed that mark with my 383. I'll definately keep you posted as to what it does tho and we'll see what the limits of this HSR intake are. The biggest support for this manifold was a guy that made 500whp thru a 427inch small block n/a. Thats getting it done!!
1989GTAtransam, good to hear you got that car together and are ready to go again. Hopefuly the exhaust is not a big restriction and you can get the tune in order and see the numbers your after
#145
Re: Our quest for a better flowing TPI
ya thanks orr . yup i know ur tryin to break the 400 rwhp mark ive been following all your posts and goals or is it called stalking lol. thats killer that guy got 500 hp id bet that if the hsr were opened up right it would exceed your goals thanks for the info and ill be waiting for those results
#146
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Car: clapped out 84Z
Engine: 355 efi roller
Transmission: tremec TKO
Re: Our quest for a better flowing TPI
Well after doing a little reseach, I'm amazed at the numbers on the AFR heads to my Edelbrock. With that being said Would it be best for me to get my heads re-worked especially to save money. Or get say the AFR'S 195. I don't care about emissions since my IROC is now under show car insurance, which means its emission exempt.
flow numbers look good on paper, rwhp #'s deliver. It's not just the # it flows, but how it flows. I would ditch those edelbrocks and go to a set of those new AFR 195 elimnators. btw, my 355 I posted about before put down 391 hp to the wheels. Too bad I can't drive it well enough to get in the 11's.
#147
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Car: '88 Camaro
Engine: 5.7 L98
Transmission: 700R4
Axle/Gears: Borg Warner 9 bolt w/3.27 lim. slip
Re: Our quest for a better flowing TPI
Details on said 355? Your vB garage is empty. I'd settle for 391rwhp if I could still pass CA. smog and keep my TPI.
#149
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Car: clapped out 84Z
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Re: Our quest for a better flowing TPI
10.25 to one flattops, balanced and blueprinted bottom end, and a pro-ram single plane EFI setup. Running 1 3/4 SLP's and a single 3" exhaust with one of those straight through dynomax mufflers. It did manage to pass the MD smog test too.
#150
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Car: '88 GTA, 90 Formula
Engine: 5.7 TPI, fed growth hormones
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Axle/Gears: 9bolt
Re: Our quest for a better flowing TPI
Just keep that in mind. I had mine ported, but they cannot reach the AFR numbers because of several design issues, a primary one being thinner valve stems on the AFRs, it's right in the middle of the port, and you just can't reproduced those results with a larger stem valve. The entire experience was a lesson in spending a little to get a lot.
TA