So im about to sound stupid.. but this has been on my mind.

My first car was a LS1 then another LS1 then a LT1 so the SBC stuff came last haha..

I found a deal on a accel coil and figured id pick it up if i can use it.. but I have a HEI distributor and the coil is in the cap... So is it worth it to get a aftermarket coil? and how do i even go about installing it, Swap the caps??

 

The coil can be removed from the cap. You need the proper coil to fit the large cap hei you could also swap to a small cap hei if you wanted and run the coil seperate like the later models do.

 

I may be doing something similar in spring. Summit(msd) sells an adapter to allow use of an external coil. There is a pic of adapter in the HEI kit to replace the internal and go external(MSD) coil with an ignition box. I dont think you need the ign box unless you plan on losing the module as well. I am going with a digital MSD model 6A with the adapter and a MSD coil.

 

I picked up the mr gasket 1480 air cleaner and it fits perfect( I switched to small cap hei) wouldnt fit if I still had the large cap hei just in case anyone was wondering. They do have a 8" diameter version that fits under the vette hood cause I also tested that one out too

 

I've been a member here for a while, been doing more reading than posting, but I did this to my 83 trans am about 3 years ago. I put in a stock 350 from an 89 truck first, then add a performer intake and single tbi unit. Huge difference in performance! it had way more low end torque, but still ran out of breath by around 4000 rpm. drove it for about 2 years, with the stock ecm. What I noticed is that the ecm had it run too lean no matter what I did, if I raise the fuel pressure, it would run great untill the ecm leaned it back out again. eventually I had a problem with a sticky intake valve, so knowing me I did what any other person would do, I installed a set of s/r torquer head I had, and of course installed a lt4 hot cam. Got it running a few months ago and It has run like crap ever since. It runs great when the engine is cold, when it warms up, its so lean I can't drive it. I just recently put on a 454 tbi unit to see if it would richen up. I think it's worse. It runs quiet and supper smooth when cold, but after that it's not drivable. I noticed today when it warms up the injectors are going from 1 extreme to the other by watch the spray pattern while idling. Eventually, they will go so rich it will flood out and die. Any idea's on what to do? I'm wondering if I have a bad ecm ground.

 

Check your coolant temp sensor, I don't know if you have the oem type sensor & connector. The latter ones are much more reliable.
Make sure the map sensor is working good & thats its hooked to a true manifold vacuum source.
Check your fuel pressure, maybe the pump is getting weak.
The ecm can only dial back the fuel so much on these early tbi systems, you need to match the injectors to the engine, a pair of 65lbs/hr is good for a 350.

 

I've checked all the sensors with a snap on scanner. It has the early type connector, there are no glitches when watching everything while running, but the ecm is do slow, I'm supprised it runs the engine at all! It has the original map from the 305, someone told me I need to have a 350 one in there, but I don't see why, plus it ran ok before.

 

IMHO you should read a sticky that covers 305 to 350 conversion and tuning. In addition, a LT4 hot cam is a bit too much for a stock calibration (which BCC do you have in your ECM?). In your post you did not mention injector size you are using in your TB. This important together with fuel pressure to have a at least a fighting chance.


//RF

 

350/305= 1.15 One could increase the fuel pressure 15%. Your fuel pump may not be adequate. Cheaper than buying injectors. Not sure if it is linear in that respect. you need to do a datalog to determine if the resulting fuel trims(BLM) are close. winaldl is easy to use in that regard. Need an aldl cable.

 

Ronny

It is not linear - it is a square root ratio: SQ(New GPH / old GPH) * 13PSI = NEW PSI

//RF

 

Thanks. I have a calculator that shows the increase in FP needed for increased HP. Like stock 305 is maybe 160 and 350 may be 190 HP. 305 cid 12 lbs FP with 45 lb injectors are good for 163 HP. 350 cid at 17 lbs FP same inj is good for 195HP. Assumes a safe BSFC and 80% DC.

 

I read the 305 to 350 thread, alot of good info, but am still using the ecm, knock sensor, and ign. module from the crossfire injection. Those are on my list of things to do next. I was running a tpi fuel pump with 55 lb injectors with the pressure raised. I just put on a 454 tbi unit that I had here with 90lb. injectors to see if it would richen up for know and make it drivable. It actually runs better, but the ecm still leaned it way out after it warmed up. It idles much better though. I can get the ecm, wiring knock sensor and module for free from this 91 454 truck. I can use the ecm, but what about the prom, knock sensor and module?

 

Prom definately not. KS probably not but try it and see. Module I am not sure. Check to see if part #'s are different?

I replaced the crossfire induction with a 7.4l tbi "SYSTEM".

 

How did your crossfire to 7.4 swap go? Is it a 350 or 305? What mods do you have on the motor? How does it run? Did you burn your own prom? Details please!

 

Depending on calibration and ECM part number SA tables from 91 454 might be very conservative. Some 454 were equipped with 1228747 ECM which depending on applications omitted KS + ESC module. SA tables were setup for BBC designed to pull heavy loads without pinging while burning regular gas. These are less than desirable for F-body!

I would look into data logging O2 voltage (WinALDL) to make sure that it is correctly swinging (0.2 to 0.8V) once it goes into CL.

//RF

 

My swap went well cause my friend is a pro engine builder and more. vette restoration shop
.
350 cid 84 vette holley projection manifold 7.4L TBI tpi pump edel rpm 64cc heads(late edition cnc) comp 224/230 @114 crane roller rockers(1.5) dual ext with crossover hook muffs EBL innovate WB nos n20 with 75 HP jets

 

That's great info on the truck system, I didn't know that, I would've thought that a ks would be important for towing applications. I can't find the thread now, but I read somewhere that the ebl system can be used with it. Am I right? Or am I better to get a different ecm?

 

I can take a complete wiring harness out of a truck, or a p series chassis if I want. Would it be easier or better to locate one from a firebird instead? Would it be more of a plug in and I'm done? It's going in a 83 crossfire.

 

Truck harness has some minor difference vs. F-body and unfortunately it will not be a direct plug in into your 83 crossfire. Some modifications will be required, but they are not too bad. In fact for carb to EFI retrofits that's what I use - I find 87-92 C/K donor truck or a van and use its harness, sensors. Further, to make it all work you'll have to install 2000 ppm VSS (unless 83 has VSS - do not know) inline with mechanical speedometer cable, wire in P/N switch relay circuit, and if you want to retain TC functionality brake switch will have to be replaced with one that has NC contacts in addition to normal NO set for automatic trany cars. Simple enough...

In your case the HAM board is an easier alternative or if you are very adventurous get 24 and 32 pin ECM pig tails from JY, get new connector pins from Mouser electronics and re-pin your ECM interface to match 8746/7747 ECM I/O.

//RF

 

It has a vss sensor in the speedo head, so that should work I hope. The ham board is nice, but my harness is in poor shape, so ill figure out which will be best. I'll be ordering the elb flash soon and am looking forward to swearing a lot now! What brake switch do I need to get? I thought all the ones with tcc were the same.

 

Last I heard the HAM boards were out of stock BO.

 

Take a look at your brake light switch - if it has two sets of terminals you are in good shape. Since I did not know if crossfire originally came with TH350C/ 700R4 - equipped with lock up converter this is why I raised this question. NC - normally closed set of contacts provide power to TCC solenoid located in trany. The moment you step on brakes power is removed and TC lock-up releases. Alternatively, source GM# 25524845 brake switch which has the required NC set of contact needed for TCC operation. Insomuch, you can drive without lockup at the beginning - fuel millage will suffer a bit.

EBL makes tuning life easy - no swearing required. Get couple clean ECM's from JY (always have a spare) pay no more than $40 for unit. Either 1228746 or 1227747 should work just fine with EBL.

If you source C/K (aka truck or van) harness you will not have IAT connector. You can live without it (and disable IAT in EBL) or if so inclined add this circuit. If you source your harness from JY make sure to take your time and gently remove it from the donor vehicle. Be very picky - oil covered harness or previously repaired harness should be avoided. Connectors are prone to crack with age (especially tab's) but these can be easily replaced with proper connector tools. Pin removal tools and replacement connectors bodies are readily available.


//RF

 

My donor truck has a 16147060 ecm in it. Ive never heard that one mentioned, I'm betting because it wil not work?

 

The '7060 is a PCM - power train controller designed to control engine and trany as a unit. It is an advanced computer-controller (P4) and has better performance vs. earlier 1228646/7747 C3 ECM's. The EBL is designed to incorporate advanced features (and more) found in PCM's into earlier ECM's, but can not be used with '7060. You can still use '7060 PCM in your crossfire, but there will be some DIY involved. The '7060 uses $85 mask and there is some support for it in TunerPro EPROM as definitions are available. You'll have to purchase either a chip burner and some FLASH chips or Moates APU1 system to make EPROM changes. If you go down this path you'll be better of locating 16197427 PCM - which was used in 94-95 trucks and vans. The '7427 definitions have been developed extensively vs. '7060 PCM. The good thing that I/O interface (red and blue connectors) is the same for engine side of the harness. Transmission side of the harness may be different - which trany do you have in your '93 donor??

//RF

 

The trans I think is a 4l80e, but don't know if I can rob that, its not my truck. I also have a 95 p chassis that could have the 7427, I was looking forward to the ebl since this I'm a first timer. I think I'm better off with the 700r4 too, the 4l80e might be lots of fab work.

 

If the 4L80E is good, and you can get it, go for it. If you are already using the harness, find a '7427, and run the $0E mask. The 4L80E is awesome. You will need to do a little bit of fab for the mount, shifter, and driveline. But it is well worth the upgrade. The '7427 also has the ability to run 1 or 2 electric fans with the addition of some code.

 

I'm thinking ill stay with an ecm for know, keep things simple as possible. I've been doing lots of reading, and confused myself! I was over on the moates site, and its all written way over my head. Is there a good thread somewhere to help understand? Do you have to keep burning chips with the ostrich? Or just plug in? Seems way more complicated that the ebl flash.

 

With the Ostrich, you plug it in similar to the EBL and make realtime changes. if you decide to remove the Ostrich then you need to burn a chip to put back in. I like the Moates/TunerPro stuff because it is completely user configurable, and I can replace my PCM easily if something happens to it.

 

Look into APU1 - even though it is more money than Ostrich 329 vs 175 the convenience of having a burner - emulator - data logger in one package. Read through product documentation to understand features of this all-in-one, datalogging, realtime emulation tuning, and chip burning hardware.

//RF

 

The Ostrich I would consider a temporary substitute for the chip. It is a tuning tool. It resides at the ECU in place of chip as you do a series of corrections of the .bin file. Once corrections are complete(maybe 100+) then you burn a chip and remove Ostrich.

Ostrich is portable EBL is not. Other than using it in another car. I would say EBL is an ECU. Ostrich is an emulator or substitute for a chip. EBL is also a datalogging system.

 

Is there a thread or a website somewhere that will explain what all this means? Sounds like datalogging and emulation are a necessity, but I havnt found any info that will take a step back and explain all the terminology clearly. I'm not too old of a guy, but I've always resisted technology, I still think a well tuned carb will do the same thing and is easier to tune. But I want this one to actually show up to pass smog for a change! But anyway, I figure I gotta join the 20th century at least!

 

stickies in DIY-Prom board right here. "free tune" in stickies on TBI board.

check out dynamicefi.com and clink link "intro to tunin part 1 and 2".