So with a new season approaching, I am considering next steps on my 88 IROC. Currently sits with some basic changes (Headers, No Cat, Borla Exhaust, AFPR, 3.45 gear) and some not so basic - Vortech kit. this is the old school bolt on kit that retained the MAF. Uses a FMU, booster pump, and boost referenced timing retard box. Currently hitting 6PSI. Also, the injectors have been changed to Bosch 3's and P/N shows them to be the 22lb units. I know there is some power left on the table with this combo running the factory tune.

I have done a fair amount of reading on tuning and "I get it" as in it all makes sense, but I know the devil is in the details and there will be a learning curve and iterations to get things right.

Looking at my options:
1. Keep factory set up, buy chips and tuning equipment and burn chips
2. Go aftermarket to a better set up

My questions are, Keep factory MAF set up and burn chips or go aftermarket? If Aftermarket, Some systems don't work with boost, which would be best to handle a boosted application on a TPI?

Long term plan will be to get a strong tune dialed in on the L98 as it sits. Then once I feel more confident about being able to dial a tune in, move to additional mods. Up to maybe dropping in a ZZ6 with a FIRST on top of it. Could be as simple as a cam swap to one optimized for forced induction. Could be things in between like adding an intercooler and more boost, larger injectors and fuel pump to do away with the FMU, or could just find I am happy where it is when I get a solid tune dialed in.

 

Couple ways to do this. You can keep fmu and as long as your fuel pump can flow the gpm needed to supply that motor with elevated fuel pressure then just tune the maf setup to compensate for any fueling mismatch.

for instance if the fmu is too rich or too lean, you can use pe mode enrichment vs rpm to control fueling to keep it more in line where it makes best power.

Timing control you are stuck with a locked out value, somewhere likely between 4-8 deg less than na normal of 34 at wot. Typically...

or get an ignition box that has built in timing retard via map boost signal. That will take care of that.


those methods will handle some additional boost and some future mods OK


if you really want to step up power, and do alot of customizing future mods, might as well convert to map sensor based fuel control. Dump fmu, get proper sized injectors and pump. Try boosted $8D and repin. Code $59 could work but these are more for experienced tuners. Esp code $59.

EBL p4 can handle boost. I did a car with this system and it works nicely! Its a great option.


else really step up and go holley HP and might as well go coil packs and sequential injection

 

It has the box (MSD) currently in conjunction with an MSD 6AL, but uses manifold pressure just like the FPR. Dial inside the car... 1-2-3-4 degrees of retard per PSI of boost selectable - currently set at 1. I would imagine this is pretty consistent and gives me that feature. Wouldn't any system allow the WOT timing table to be adjusted knowing this compensation exists. Results will be the same in the end, number on the curve in the tune minus the retard from the box? That is one way or just do away with it and dial the timing curve in. It is my understanding this is the old way of dealing with "bolting on" a blower and not getting a custom tune for the timing map. This type of system is probably more useful for NO2 where it's not always on and you want a different timing curve under spray than NA, but obviously this box works off boost pressure and wouldn't function properly with just NO2.

No problem converting it to MAP. I have no love for the MAF Code 36 . In fact, most of my reading has been focused on using MAP based systems.

The wildest I see is going to a ZZ6 with a Cam swap. It seems the most logical step power and simplicity wise. Drops right it, my accessories bolt right up including the blower, but will need a non factory intake to feed it I am sure.

 

Yeah if you have the box already then you are good. Boosted map based codes usually have timing tables for the actual boost pressure. Basically works the same way.

in the end depending on boost you may need the ignition box anyway. I’m not sure, my stock 305 didnt gain anything with the box vs stock hei ignition. But i think my cap may have been cracked and arcing spark. Had a hell of a time lighting off just 7-8 psi til plug gap was super tight. Didnt have the problem with my 400” motor at 15 psi with a box tho

 

I still have the old Vortech instruction that cam with the kit. The PO may have rigged a few things over the years, but he certainly kept good documentation and most was done right. Anyway, both boxes came with the kit and were part of the installation. The 6AL may just be more of a precaution.

 

I would round-file all that old garbage and go to a stand-alone. We have plug-and-play LINK ECU kits that don't require any wiring changes other than a switch to a MAP sensor from the MAF.

GD

 

Forgive me to being new to this particular area of the forum, but who is "we"? I searched LINK ECU and the website found doesn't show anything directly related to TPI.

 

Check the classifieds for a used EBL system or another aftermarket system. The burning chips route has sailed long ago and equipment and support will dry up as well as being tedious. You have way more control over boost fuel and timing curves vs what you have now. You will add more mods and boost later, so plan for it now by getting better stuff. You can find used 60lb injectors on various boards for cheap now, and put in a walbro 255 hp pump which is good to 500rwhp.

 

Not to knock the ebl setup but for what it costs, a few hundred more and you can have a new terminator x efi that is sequential and will more than handle your cars setup

 

Do you have any info on this LINK ECU that we cant seem to find any trace of here on the board? It seems if you were promoting a viable option you would have links and pics of this option as it directly relates to our systems. I want to see one of these ECUs plug and play into a car. Not being an *** at all. I just have never heard of this and havent seen a plug and play ecu in one of these. Would be a great option.

 

We make them to order. There will be a page on my car (86 Trans Am) that's currently running the adapter harness to the 7165 ECM up on the LINK website as soon as the webmaster in New Zealand gets it finalized. Here's some pics of it installed before I tucked it back under the dash:




This harness includes the ignition bypass relays to control the stock TPI distributor (large or small cap), and only requires swapping the MAF out for a MAP sensor (GM 3 bar, or whatever you like), and bypassing the external knock module (two wires joined at the module connector). It's literally 5 wires and you have a stand alone. Of course the LINK is capable of a LOT more if you want to add wires for full sequential injection or COP ignition with crank trigger wheels, etc. All of which is available from a number of sources.

Benefits over stuff like the Holley and FAST systems:

• No re-wire. Uses stock harness and distributor.
• Lifetime warranty.
• Easy tech support - no hold queue with a different "agent" every time.
• Myself and the VP of LINK North America are available for remote tuning (on your local dyno, or for startup in your driveway, etc).
• 1 hour of remote assistance to get you started and idling included with all our packages.
• Full stand-alone capability. Change any input and output to do whatever you want.
• Turbo and supercharging, Nitrous, Meth injection, etc......
• Closed loop with hyper accurate LINK CANBUS lambda module. No more failed LSU 4.9 sensors and no sensor grounding problems with analog stand-alone wideband controllers

There's lots more I'm sure. We can do a harness for the 7730 also but so far we haven't found a source for the blue connector header so we have to cannibalize them from old ECM's (not that big of a deal - they are cheap used).

GD

 

How much would this setup cost?

 

The LINK Extreme-X, CANBUS Lambda module, and adapter harness would be $xxx.

This is most comparable to a Holley Dominator (Currently $2108.95 without wideband or harness, etc) but without the need to completely rewire the car. Though you could if you wanted full sequential injection and COP ignition, or a drive by wire throttle, etc. This packages gives you Dominator level of tuning and capability without the ridiculous number of inputs (Who is going to actually use 30 0-5v inputs...... analog sensors are on the way out anyway in favor of digital acquisition with CANBUS) and includes everything you need for about the same cost as JUST the Holley ECU without wiring or sensors.

GD

 

That setup seems very interesting. Does the smog pump and evap canister still function? Along with the factory speedometer? Any chance we could get a wiring diagram/pinout of the plug and play setup? Thank you!

 

Sure. You can accommodate all those functions within the LINK if you want them (factory speedo doesn't depend on the ECM in any way). I'm not currently using them - I'm using those wires for other purposes (CANBUS signals for the CAN Lambda module, Additional temp sensors, and an MSD DualSync distributor so I can run full sequential injection). The programmable outputs can control anything you want them to control - they can be tied to relays, pull high or low, and drive PWM, etc. It's all very universal and flexible. I'll try to attach my spreadsheets. The first one is basically replacing the stock computer while the second is a full sequential setup using an MSD DualSync distributor. I added 6 wires with a bulkhead connector right above the factory harness bulkhead under the passenger fender for the additional injector drives and merged them into the factory harness. So I have full sequential injection with a 95% factory harness (100% stock in appearance) only having to add 6 wires.

GD

 

Hey if it has "SELF LEARN" feature or something that can get ya up and going realitivley "SAFE" like a holley hp etc can, then fine tune on a dyno, i am game for one on a 7730 MAP setup...