renegade intake? for cross fires

87vette81big said:
That's not Shorty Accel Spark Plugs I recall using.
They were Yellow Ceramic insulators with a Nickle Chrome plated hex base.
They were about 1.00" shorter than standard Accel plugs and other manufacturers plugs.
Click to expand...
That's what I thought Brian, my shorty plugs are real short. With the addition of the gasket I am going to use I will have a lot of clearance. Mine are very bright yellow, think they look cool with all my other colors, they are also copper core.
 
Its been almost spring the last few days, i had a muffler shop expand my muffler inlets to fit the 2 1/2 in exhaust.

They did not think it could be done but it fit!

I took the car for a little spin and the iac's set and my idle is normal.

The car still needs some work, i think my tps is on it's way out but the car is very fun!

I think my mufflers can't handle it, when romping on the throttle they are rattling like crazy and i think i shot out a bunch of muffler innards lol

I still have to narrow down some running issues, but i'll start with a new tps and mufflers first.

I'm also keeping in mind my wires might be shorting out, i could not make out any blue sparks...

I also installed the distributor module, i noticed it came with dielectric grease with a note saying its for thermal conductivity...

The unit i removed with a napa tag in it had thermal grease...

Anyways i used the supplied "thermal grease" for connections, and used some artic silver 5 i had laying around for the thermal connection...

The car revs faster, and it wants to rev higher, very fun!

I do have a slight hesitation around 3500 rpm, it feels like it's missing a little...
 
the mufflers may not be securely, supported in a way or location that prevents them from rattling against some other surface, the restriction to flow should be very low.
how does the cars power curve feel? check your fuel pressure ,and ideally check your fuel/air ratio, you might find its not keeping up and needs to be increased, try to get it matching the engines needs, thats a VERY common issue with those cross fire mods, you might find thats the cause of the "MISS", Id try bumping it up at least 3 psi, you should be running 12 psi-14psi not lower, if you don,t have a adjustable fuel pressure regulator you might want to convert to a good one
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AFR_Torque.gif

Octane_Requirement.gif

Stoich.gif

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related info
remember the sub links hold most of the info

http://garage.grumpysperformance.com/index.php?threads/1984-fuel-pressure.11776/#post-55675

http://garage.grumpysperformance.com/index.php?threads/fuel-line-sizing-return-vs-feed.3067/

http://garage.grumpysperformance.co...s-air-flow-vs-speed-density.11952/#post-56852

http://garage.grumpysperformance.com/index.php?threads/carb-tuning-info-and-links.109/

http://garage.grumpysperformance.com/index.php?threads/setting-up-your-fuel-system.211/

http://garage.grumpysperformance.com/index.php?threads/fuel-pressure-regulators.635/

http://garage.grumpysperformance.com/index.php?threads/setting-up-your-fuel-system.211/

http://garage.grumpysperformance.com/index.php?threads/1984-fuel-pressure.11776/#post-55675

http://garage.grumpysperformance.co...p-after-running-out-of-fuel.11309/#post-51444
 
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Thanks for the info!

And one thing i noticed was my mufflers did have a bit of internal rattle, while driving i noticed one muffler suddenly got louder.

I thought i might have lost it, or it disconnected... :rolleyes:

And i found one of the throttle bodies did not have a plug on one of the vacuum pipe, possible this contributed to the miss.

The way it was running did feel like fuel related...
I'll check the fuel pressure, and i also noticed while using my timing light to brighten up my fuel spray pattern, one fuel injector has a wider spray pattern...
The spray looked good, just weird...
 
Last night i adjusted the rockers to ensure its not the knock sensor or something silly.

Took it for another spin and i had the same problem. Weird thing is i can work past the power loss point, almost seems to be related to where the throttle is.

While adjusting the tps yesterday i noticed that manually moving the tps sensor arm has almost a dead zone while watching the fuel injector in that mid area.

Also moving the tps to the max and bringing it back will randomly change my idle voltage.

And to make it even more anoying, the first 5min or so the car is fine.

I need to watch the voltage while playing with arm...

And to explain the power range leaving out the little issue... I left two black marks pulling out of my culdesac, getting out on the road and shifting the car manually the power just keeps rising, no noticeable power drop off like before, but instead i have a nice power band that pushes me back in my seat and a smile on my face!

I have a new tps sensor on order, hopefully thats the issue...
 
yeah you should have a rather noticeable power increase over the original engine,
Id suspect at least a 100 hp plus so the original engine put out about 200 rear wheel hp
you should now feel a significant boost over that

the stock 1984 cross fire cylinder heads are pathetically restrictive
more info
just a bit of info on those stock #624 head flow rates

.......intake....exhaust
.100..44..........41cfm
.200..101..........82cfm
.300.155..........125cfm
.400..182..........137cfm
.500..196..........140cfm
1984cr.png

http://www.vettefacts.com/C4/1984.aspx

if you just calculate the bare minimums
the new headers and low restriction exhaust should allow a minimum of 35-50 more hp
the cam upgrade and heads an easy 45-55 plus
boosted compression, an easy 10-15 hp
the intake an easy 25 hp
rocker arm ratio change maybe 7-10 hp
so a 115-150 hp gain would be very likely , probably even more with a bit of tuning ,
and I would certainly not be shocked to find it closer to 150 hp gain at the rear wheels... think about that,
a few well selected, and reasonably selected mods will allow the car too far more effectively access the engine potential power,
gaining about 70% additional, effective power,
when rated against,
the original engines power or 205 original compared to potentially about 350 hp now
Car = 1984 Corvette with Z51 package

Intake = renegade crossfire: ems-msren-100p http://www.summitracing.com/parts/ems-msren-100p
Intake bolts = ARP 12pt: http://www.summitracing.com/parts/arp-134-2101
Camshaft = Crane 114132: http://www.summitracing.com/parts/crn-114132
Camshaft lock plate: http://www.summitracing.com/parts/crn-99168-1
Rocker Arms: Scorpion 1.65 ratio http://www.summitracing.com/parts/scc-scp1008 (to give total lift just shy of .500)
Head gasket = SCE copper .021 thickness: http://www.summitracing.com/parts/sce-p11062/overview/
Timing chain = Compcams magnum double roller: http://www.summitracing.com/parts/cca-2100
Head bolt set = ARP 12pt: http://www.summitracing.com/parts/arp-134-3701
harmonic balancer = Summit Pro Street 6.750in: http://www.summitracing.com/parts/sum-161350
harmonic balancer bolt = ARP 12pt: http://www.summitracing.com/parts/arp-134-2501
Valve covers = Edlebrock Signature series: http://www.summitracing.com/parts/edl-4449
Heads = Edlebrock EStreet 70cc pn 5073: http://www.summitracing.com/parts/EDL-5073/
PushRods: http://www.summitracing.com/parts/sum-g6400100 (Adjustable pushrod was key here)
Headers = Melrose brand with ceramic coating option, came as a package with 3in exhaust: http://www.melrosecorvette.com/1984-1985-l98-corvette-header-system/
Header gasket = Felpro 1406 http://www.summitracing.com/parts/fel-1406 (they matched up with the edlebrock ports perfectly)
Mufflers = FlowMaster 40: http://www.summitracing.com/parts/flo-80430402
Sparkplugs = Champion RC12YC http://www.summitracing.com/parts/cpn-711
Ignition Module: http://www.summitracing.com/parts/dui-000333 (not installed yet)
crossfire balancing info: http://www.thecubestudio.com/CrossfireThrottleBodyBalancing.htm

Transmission: stock 700r4 for now.
Transmission TV cable: http://www.summitracing.com/parts/atp-y225
Click to expand...
 
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Last year i took a 2002 c5 out for a test drive, my current power increase feels like more than what that base c5 had.

That leaves me pretty happy!

And a little more on my current issue, right in that power loss point the car will backfire a little, even giving me a little flame up the intake...

Manually moving the tps sensor into that deadzone will also cause the car to sputter and backfire...

It's a little anoying if thats the issue it suddenly showed up with the upgrade, i tried to make sure the car was running near perfect before the upgrades started.

And it's also possible i damaged a spark plug wire or two...
Or it is shorting through my thermal wrap...
 
Can you hook a meter to the TPS and measure a smooth resistance from
fully closed to fully open. If not, then it sounds like you have found the
problem ..... problem solved!
 
yes a defective TPS sensor on an older early c4 corvette is almost expected,especially with that sensor approaching 32 years old if its OEM.
ricks suggestion to test the TPS sensor is a good idea


http://www.ecklerscorvette.com/corvette-throttle-position-sensor-1982-1984.html
84tpssen.jpg
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http://www.ecklerscorvette.com/corvette-throttle-position-test-switch-wiring-harness-1984-1991.html

A MULTI METER AND TIMING LIGHT WILL BE USEFUL
image_12926.jpg

yes you can find a good deal more info in the links
http://garage.grumpysperformance.com/index.php?threads/ported-crossfire-383.10240/#post-41071

http://garage.grumpysperformance.co...lay-switch-locations-and-info.728/#post-54562

http://garage.grumpysperformance.com/index.php?threads/1984-fuel-pressure.11776/#post-55675

http://garage.grumpysperformance.co...sfire-vette-won-t-run-right.10096/#post-39656

http://garage.grumpysperformance.com/index.php?threads/got-a-cross-fire-corvette.640/#post-25767

http://garage.grumpysperformance.com/index.php?threads/bits-of-crossfire-info.1148/#post-5322
 
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Thanks, and i replaced every sensor except the tps sensor, using the updated modules if available.

I suspect the tps is the original...
And if not the original, its old.
 
Your stock injectors are gonna have a hard time keeping up. Grumpy's right you need to bump up the pressure to about 13 psi. Even then the stock injectors will only support about 250 hp max. Getting to 15 psi will get you up to supporting 265 hp You are getting into the range of needing to be able to program your PCM. Excellent parts list, btw, that will make it easy for others to replicate. How's that power increase feel? It's nice not having the motor fall on its face at 4k rpm isn't it?
 
last year before the tear down I bumped the fuel pressure to about 13psi using a cobbled together hose adapter that leaked a bit.

Before reinstalling the throttle bodies I gave the built in regulator a few more turns, not quite max but getting close.

I bet it's right at 14psi or real close.

As for fuel injector upgrades, will a pair of these babies work? http://www.amazon.com/gp/product/B000FRTZJU
(from a 92 caprice)

I'm still a little grey on the pcm upgrades, I know DCS use to offer nice packages, but no longer.
I very much want to be able to reprogram this thing, this is something I have been wanting to learn for some time now.
(also being that one of the purpose of this car is a toy I can tinker with... ;) )

I also upgraded the fuel pump from an 86 or 89 if memory serves me, it required a new ground... lol

And the power increase feels fantastic, it feels like how one would expect a sports car to drive. :)

Now right where the car use to fall on it's face I start feeling the car wake up, reminds me more of my old RX-7, but cooler/meaner. :cool:
That thing loved to redline, it seemed to need it!
 
Also I want to add that the rear exhaust hangers I picked up are from a C6, and they bolted right up to the rear end!
I have them dangling right now, I need to figure out a bracket idea, that or I'll just weld them directly to the tubes.

I'm pretty sure they are a small part of my rattle source right now :D

(someone else's picture)
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if your reading this and are not familiar with the c4 corvette drive train configuration or what a c-beam is this may help
Image from the ebay ad (the ones I bought)
upload_2016-2-22_5-27-33.png
 
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I don,t know if that fuel injector you linked to will fit and function in your 1984 corvette, but I do know that if you look around your area your almost sure to find a local efi /fuel injection shop that can sell you upgraded higher flow rate injectors that will fit, your particular application.


heres a useful thread with some calculations youll want.

http://garage.grumpysperformance.com/index.php?threads/calculate-fuel-injector-size.1200/

http://www.witchhunter.com/injectorcalc1.php

http://www.rceng.com/technical.aspx#Selecting_the_Proper_Injector_Size_

a quick bit of math suggests youll need two injectors that are larger than stock (roughly a bit less than twice the flow rate of stock)
calculations based on horse power suggest the stock injectors are about 30%-40% under size for best performance Id suspect youll want something flowing more fuel, the injector supplier should be able to suggest something compatible, in flow rate per hour to max out the throttle body intake induction system, and of course it will work far more efficiently with a bit better soft ware controlling the injectors or at least a skilled local tuner.
youll see and feel the power increase from the better fuel/air ratio control once its done correctly
Timing_Torque.gif

AFR_Torque.gif

Octane_Requirement.gif

Stoich.gif

volumetricz.jpg

volumetric.gif
 
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Drawman 44 is Pretty Well Versed With EFI Tuning these 1982, 1983, &1994 Crossfire Engines ( 1983 would be Z28 Camaro & Trans Am).
He is back to work.
Maybe he will bw back on Geumpys tonight.
He knows more what it takes to EFI Tune Crossfires than me.
 
I sent some emails out to some local EFI shops, pending a reply.
I also sent one to an EFI shop on ebay that had some 90lb injectors offered for a 454, he suggested they would work fine...

So using my amazon account knowing how nice they are with returns, I ordered a single injector for an 88 7.4l big block.
It took some digging to confirm what kind of fuel pressure that thing runs, but I found a reference of 10psi.

if it looks like it will fit in my tower I'll order a second injector.

if it runs ok I'll look into more flow and see where that takes me....

I still need to figure out the whole computer refit...
DCS had it all figured out, but they don't have anything available any longer...


And doing some searching around I found this nice little parts list that might help others... assuming these turn out to be compatible... :)

5235279 - White / Green - 54pph - 5.0L / 305 Cars/Trucks

5235206 - Orange / Black - 61pph - 5.7L / 350 Cars/Trucks

17084327 - Yellow / Brown - 65pph - 5.7L / 350 Police Package

17084304 - Black / Blue - 74pph - 7.4L / 454 - 91-93

5235231 - Red / Blue - 80pph - 7.4L / 454 - 88-90
 
GOOD FIND!
And doing some searching around I found this nice little parts list that might help others... assuming these turn out to be compatible... :)

5235279 - White / Green - 54pph - 5.0L / 305 Cars/Trucks

5235206 - Orange / Black - 61pph - 5.7L / 350 Cars/Trucks

17084327 - Yellow / Brown - 65pph - 5.7L / 350 Police Package

17084304 - Black / Blue - 74pph - 7.4L / 454 - 91-93

5235231 - Red / Blue - 80pph - 7.4L / 454 - 88-90
Click to expand...
 
So remembering some information provided earlier on about computer upgrades, I'm browsing around here http://www.dynamicefi.com/EBL_Flash.php

it looks like I need to get a connector from a newer car and adapt my current plug.

Remembering what it was like just being able to swap the prom in my computer... sounds like I might need to do some disassembly to get some space to work on the harness.

It's also not clear if I need to do any prep work on the computer prior to firing it up (programing ect), or if I can get them to do a base programing to start...
 
Update,

I installed the new tps sensor, that helped to clean up the idle however it still ran a little rough while driving.

So i installed the 454 injector.

Much better!

I have the second injector coming monday.

Next issue...

TV cable connector end is a total pos, i had noidea however the aftermarket cable end popped off of the throttle bracket.

Weird thing is it shifted hard, however it also shifted super late.

I did not get the feeling it was loosing pressure, but instead it felt like what i would expect with raised pressures.

I even made it through gears, however od never locked in for me.

I unfortunately drove for a few short intervals of about 10-15min each, and the final one was a good 25min when i decided i better readjust the cable.

I reconnected the tv cable and adjusted it to the most firm i could, and zip tied the end to the bracket so it can't pop off again.

It seems to drive fine, i can't detect slipping, each gear is working and the fluid looks good.

I also don't get the super harsh 1-2 shift like i use to get before touching anything...

Thoughts?
 
 
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