I was reading through a book titled "Camaro Bolt on Guide" and ran across this Accel unit that has me interested. The entire kit comes with the ECU, injector harness, TB, air cleaner, fuel pump, fuel filter, coolant temp sensor, air temp sensor, TPS, MAP sensor, IAC motor, O2 sensor, and all the linkage. Accel Part #74135

WE HAVE ALL THAT ON OUR CARS NOW!!! I guess it would make a good retro kit more than anything. One thing is that Accel also recommends the use of a comp. controlled ignition system, which we ALSO have already.

What would be great is if just the TB could be bought and adapted to work with our ECM. Or even if it could be used in conjunction with our ECM. I doubt that it uses the same connectors that our stock TBs do such as the TPS, etc. But if it could be used then HELLO 4 BARREL INTAKE MANIFOLD!!!! The bad thing about it not working that way is the price for the entire system. ~$1300 through Summit!!!! UHG!!!! Plus it's only calibrated to run up to a 300 HP engine. You can reprogram the CALMAP for stronger engines by using the proper software, but that just ads to the cost of the swap. For that much money I could switch to TPI.

I would like to use the Accel TB on a mild 350 (~330HP) that I'm building for my car right now. If I could have 750 cfm (which is what this TB flows) on tap for future upgrades, then that would be awesome!!!!!!

I'm sure that if it could be done, that JP, or fast_broker would have done it. But maybe it's just never been thought of yet. I tried Accel's web site with no luck. Guess I'll have to call their tech line. Although they'll probably tell me "No" just so I have to buy the entire system.

Anywho, let me know what you all think, know, or hope for,

AJ

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92 RS w/t-tops 305 TBI Auto.
170K miles and don't burn a drop o'oil
-K&N Truck filter #1500 w, open ele.
air cleaner
-Dynomax 2 1/2" cat-back
-B&M TransPak
-Jet Stage2 Chip
-180* T-Stat w/ 185* Fan Switch
-JVC CD--Alpine speakers & 4ch. amp
Rockford Punch 100. 1 - MTX 12" sub

[This message has been edited by AJ_92RS (edited October 08, 2001).]

 

Dan W. has one. Do a search on "Dan W". I think he ran it off the truck Tbi computer. It has trouble at high RPMs if I remember. That might have been fixed by now.

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-Tas
'89 Formula WS-6

305, TBI, 700R4, P.A.W. 14x3 open element with K&N, Milodon 160* thermo, functional Formula hood, cross-flow Flowmaster, '99z28 rear pipes and tips, Hooker 1-5/8" 50 state legal headers, Dynomax 3" I pipe (PN 44063 and 43248)
Super GRK_Taz World
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AOL IM: superGRtaz



Got Beach?


[This message has been edited by Tas (edited October 08, 2001).]

 

Thanks Tas, but no luck searching "Dan W." Do you happen to know his username? Or is that it?

AJ

BTW, no luck under "Readers' Rides" either.

[This message has been edited by AJ_92RS (edited October 08, 2001).]

 

I noticed that. I edited my post above. its "Dan W"

 

Anyone else have any input?

AJ

 

I've been looking for something a LOT cheaper than accel, it's from Holley. They might not have the best injectors but so far I have no problems with my unit.
I posted about a 4 barrel TB unit, just look for it, it's recent so should be on the first page. As for getting it to work with our ecm, not hard, edelbrock has a kit that converts the TBI injector drivers to control 8 batch fire injectors with their EFI conversion. I've seen this conversion and I like it a lot. It is the same price as the accel at $1300 and it looks to be made for our engines (350, 305 TBI).

------------------
, Jon (350 TBI!)
91 Red My website

 

Thanks for the response Jon.

I believe I have seen the Edelbrock unit that you are talking about. Is it the one that uses our stock TB but fires the injectors into the runners similar to TPI?

I would assume that the 4 barrel Holley unit which you are referring to is the same as Accel's. After all, Holley is the mother company of Mr. Gasket, which is the mother company of Accel. Are you talking about the Pro-jection TB?

Have you seen the Accel unit I am refering to? Just to jog your memory, it's a 4-barrel TB (as I've already said ) that has the injectors firing into the side of the TB as opposed to them shooting from the top like stock, or even your Holley unit. It just seems that it is a better location since it would not restrict air flow nearly as much. Plus it's a 750 4 barrel. AND it bolts up to a standard, square bore carb manifold, with no adapter needed.

How much simpler could the design be? You get the flow of a carb, along with the accuracy of EFI, and it would still pass emmisions.

I guess I need to call them and find out what it would cost for the TB, fuel rails, and injectors, and see if a standard air cleaner will sit on it, no problem.

Thanks again,
AJ

 

The stock TBI design isn't terrible with cfm. The injectors actually don't get in the way much.
I do know what unit you're talking about, it's in Summit and Jegs with a picture. As for them being better, I doubt it. It's still a wet flow design like carb and OEM TBI so I don't see any real reasons why it would be better. The Pro-jection TB is what I was talking about. I think that's the unit to go with if you want a plug in. It's under $400!

------------------
, Jon (350 TBI!)
91 Red My website

 

ALl I know is a nice .750" hole 4bbl TB dry flow can flow 1000cfm pretty easily and a 1.25" 4 hole TB can flow 2000cfm. OEM small bores are 1-13/16", right? Why can't they flow 1000cfm??????????????? Or at least 600cfm, for crying out loud. I gotta flow one of these things... and the 2" bore, with and without injectors... Anyone do this, yet?????? Snuf???

 

There's a lot of debate concerning how much the fuel spray cone disrupts the air flow. Aparently, it's quite a lot. This would explain the cfm difference between comparible wet and dry flow tb's.

 

Oh, I understand that, but c'mon...

I am still interested in using a 7747 tomake a custom MPFI, like Edelbrocks conversion, but have not heard how/if there is a way to tell what injectors won't fry the 7747 ECU when hooked up like a TPI... Or how to even hook up the injectors? Series, parallel??? I guess I could try to buy a replacement Edelbrock harness by saying I melted mine or something... Then, I'd be ok??? Ineed some help with this, but I stray from this topic. sorry...

anyhow, I like Accel enough to try one of their TBI's, but you'd have my problem in needing to know if our ECU can fire the injectors and fire them fast/slow enough to get the job done. I think Grumpy is a master of this stuff...

 

Did accel buy the design from Barry Grant. Buy the description given thats what it sounds like. I wish I new more about how to design ecu's, it can't be that hard to make an injector driver board that can handle four injectors can it. Say use four drivers out of donor ecu's and run them off the ecu in the car. Oh what do I know, probably couldn't work anyway.

 

You're right the fuel is a major cfm killing monster BUT that is the nature of wetflow. The fuel takes up a lot of space and doesn't leave much room for our good old air.
The injector driver issues are very important. I made a post about my project over on the DIY_eprom board, go check it out.
I'm now figuring how to control the injectors with a custom LM IC (chip driver). Most likely they'll work until about 3000rpm and then start to flake off because of the amount of fuel and only getting half the voltage! This is why you can't just plug 4 injectors into 2 drivers .
Back onto the issue about TBI air flow. The fuel going past the throttle blades actually makes a very nice atomization. The air velocity passing the blades and the walls is very high and is like a carb in many ways.
I do not think the stock TB is all that bad for cfm. We should definatly have somebody bench flow to compair, I'm very curious if it's the fuel or the injector pod that are causing such lousy cfm ratings. Either way I just say increase the TBI unit , that way you have the cfm you want .

------------------
, Jon (350 TBI!)
91 Red My website