Hi guys, I am going to get rid of this cfi and go to tpi. I have a 83 z28 with a newer crate 350 in it, otherwise the car is really all stock. I already have a new tpi fuel pump, just need the underhood components. Before I order them I need some questions answered please. I want to use the edlebrock base and runners to start, but I would like to avoid the 9th cold start injector as I heard this is possible in some way. My question is how to delete the 9th injector since I have to go with the early style tpi base and runners cause I have early style heads? Someone told me just to get a top plenum and fuel rails from a 89 and that would take care of it, is this true and would those parts work with the intake I want? Let me also give some info on future plans I have for this car, someday I would like to replace the cam and do some work on the heads, my goal would be 12's, and my car is a daily driver and must pass smog in CA. My plan was to order the base and runners from edlebrock and find a used 89 iroc setup and put them together for my car, would this work and make the best setup for what I want with my car? Sorry for all of the questions, I am new to tpi. Oh, don't want to get into a crazy debate over maf vs. speed density, but does anyone think speed density is better for me and my cars future plans? I just want the most info possible before I start this big project, thanks guys.

Will

 

you want part number

3890

or just click this link

http://store.summitracing.com/defaul...=KeywordSearch


this is the base and runners for perimeter style heads. you can thank me later.

if you dont want the 9th injector, but want to retain MAF, you need the 89 ecm ONLY, no other year, 85-88 have 9th injectors and 90-92 use Speed Density. you will need a custom chip though because ironicly, 89 is the first year of VATS. so you need VATS deleted out of the 89 chip.

dont forget your 24# injectors and throttle body. you will also need the TPI filter housing unit. you know what im talking about.

 

Traviz got some of it right, but just for a little more info...

late '85-'89 used the 165ECM...EPROM is the difference for which setup...(with without CSI)

Edelbrock base should be drilled/angles for new and old innner bolt angles...I know my Accel is.

You don't really want to try to push it all through the stock runners, best to look at Edelbrokc/Accel/SLP's, etc to get more flow...you can't port the stockones...nothing to port, just thinwall tubing.

You need to check with emissions compatibility for your swap, just to be no the safe side of things...unless you're doing the Traviz thing

As mentioned, base should be the same for anything...runners dictate CSI or not. If you're going to be tuning the EPROM yourself, might be best to go SD on the swap, just because the DIY_Forum seems to have more info, plus the fact you don't need to spend the $$ on the MAF and the extra two relays to run it...plus the ESC is in the ECM and will come with a stock setup...yo'd have to purchase an additiona; one for the MAF setup. Also, even if you run CSI fuel rail, you can plug the end, so if the price is right, don't pass it up.

You will need to have some minor PROM work done to eliminate VATs..since your car's column won't have the wiring in it, etc.

How big a hurry are you to get going on this? What's your budget? I happen to have a bunch of TPI parts, also some aftermarket bases, ect, I probably won't be using in the next 20 years...since you're not too far away (based on your bio-line), you could actually come down and look things over for what you want/need.

 

I just cruised through Summit, looks like they do show 2 different p/n for bases...must be early/late difference with inner 4 holes. Guess Vic wasn't wise enough to just cast one base

 

actually the one i had was drilled for both, which i believe the link i posted is drilled for both because if you look at the application link.. it says all early sbc's while the other part number says only 88+ which is centerbolts

 

I saw that too...maybe they're selling off old stock or the others?

 

Thanks for the info so far guys. I did notice edlebrock makes a early style base for my car and that's the one I will order. So if the runners dictate wether or not you have the 9th cold start injector then can't I just order the later model runners, will they fit with the early style base? Oh, I am talking about the edlebrock runners just so you know, not the stock ones.

8Mike9, I am in a bit of a hurry as this is my daily driver. Money is really not a issue to be honest. Thanks for the info and offer for parts, when the time comes I will be in contact with you. Also, I would like to get into tuning, now as for speed density my brother seems to think I would have trouble running it cause it uses a vehicle speed sensor from your tranny, which I don't have now and he made it sound hard to modify, is there any truth to this? What are other advantages to SD besides saving some money on sensors, etc? I really need some hard core info on the MAF and SD setups, anyone can chime in and give info or opinions please.

 

I'd take a gander through the DIY_PROM forum, main advantage to SD is the ECM has much more capability as well has there seems to be more knowledge about the '730 tuning than the '165.

You still need a VSS for MAF, so that's a tossup. VSS is under my dash on my '89 driven via the cable...also, pretty sure there are some type of conversion boxes for swaps...I know the 4x4 crowd uses something similar that aftermarket

I'm not advocating SD or MAF...but if I were starting from scratch and had nothing in my hands, I'd opt for SD.

 

Thanks again for the info and reply, I really appreciate your help. So the VSS is taping into the speedo cable sounds like, interesting, wonder where it is on the SD setups? Sounds like something I can modify to fit my year though either way. My basic understanding of MAF is it responds to mods better and adapts more quickly, but it has it's limits and once they are reached you have to tune the rest of the way. SD is all computer controlled and doesn't respond much at all to mods unless you tune it and then it gives you the best of the 2 setups. Is it also safe to say SD is more simple and less expensive to mod and tune when you are moding your engine? Is that the real advantage to it, and is it that SD can just flat out give you better performance from your mods than MAF once it's tuned?

 

I just converted to SD a few weeks ago and absolutely love it. I had a few idling problems and after the SD swap- without adjusting the minimum throttle screw or TPS- I have a perfectly smooth idle. It also made my CAI alot easier to install, not to mention less wiring, less relays, and cheaper sensors.

 

I think only a few years had the VSS on the tranny...might be a question for the drivetrain forum, SD cars also have the VSS under the dash, IIRC. Infact, you may have a VSS as well...something needs to tell the ECM the speed?

You're pretty much correct in your MOD's assessment, MAF measures incoming airflow and SD uses preprogrammed information...but, once you start to mod the PROM, most recommend the SD is easier than modding MAF tables. The expense to modify either a SD system or MAF system is the same. I don't think the end performance is much of a factor until you really get into some serious HP where you start requiring more airflow than the MAF will allow...but that pretty high, and also a lot of RPMs too...not necessary for mid-12s.

Either setup is going to need tuning once you start with heads, cam,etc, to take advantage of it, both SD and MAF can run the stock tune with just intake and exhaust.

 

all 3rd gens have a VSS. it helps with torque converter lock up and egr i know off hand.

 

firebirdjosh, thanks for your info, it really helps me out in my desicion making. More and more I am liking the SD setup.

8Mike9, and Travis, thanks for the info about the VSS. Sounds like it won't be hard at all to swap to tpi. I will keep you guys updated about what I am going to do.

 

Hi,
I have one question concerning your CFI. Did you port the CFI intake to match up with the 350? If you did not port the CFI intake then the 350 is choked. There is a lot of performance that can be had from the CFI if the intake is ported.

I did not that the intake is ported, but I don't think TPI will buy you that much more power. The CFI intake contains tuned runners that should boost power.

 

Thanks for the input, yes the intake is gasket matched and the runners are ported some, although they could be ported more. You are right in some ways, the more and more research I do there is really not that much gain in power for all of the $ it costs to swap to TPI. I have also found a aftermarket intake called X-ram to replace the stock CFI intake and it seems to boost power more than TPI and costs only $500, nice thing is you keep all your other parts stock and retain the look, and now the same company who makes the X-ram also makes ported TBI units for my car.

 

who wants my hsr? im going x-ram now

 

Ya right Travis, you already spent too much money, stick with what you have. You are full of s*h*i*t anyway, you wouldn't switch.

 

your right.

HSR>X-RAM>TPI>TBI>CARB

 

Ya whatever, you are not going to switch to anything. Stop posting you post ****.

 

wills

I did the tpi swap on my 82 LG-4 and added 373 gears, headers awsome improvement ... ditch the cfi you will love port injection

 

The TPI swap into an 82, is vary expensive if it done right. And doing a TPI swap on an LG4 is a waste of time. The LG4 engine just sucks, I know I had one.

I swaped in an crate 350 with TPI using all new parts back in 98. The combination is very powerful. I can smoke the wheels. Gun it on curves to make the rear end come around, etc. I am still using the orginal 2.73 rear end.

His CFI setup has RAM AIR. I think the RAM AIR setups on the 82 and 83 Thirdgens are cool. So if he switches to 350 and uses the x-ram intake, he will have an smoking setup.

 

he does have a tre' fiddy

 

Thanks for all of the input guys. I have decided to stick with the CFI and go to a X-Ram intake. This way I can keep the stock hood and look, plus I want to keep my tire smokin low end torqe. I have also heard there is less hp/tq gains with TPI than going with X-Ram, and X-Ram is a 1/3 the price.

 

 

Bruce

I've finally got all the parts to ditch my LG-4 and yes I agree they suck. I have a complete L-98 and purchased SLP runners, accel lower intake. I am also pondering with the idea of running a single turbocharger. I wish I would have dyno'ed and run my stock setup and compared but I remember the stock LG-4's inability to spin it's tires on glare ice ... I would like to someday run it against a mod'ed cfi car someday, seems all comparisons evolve around a moded cfi against a stock tpi car.

So my guess is if a stock tpi car outran a cfi car two modified systems would result in the same. I have a 82 corvette so maybe I will mod it's cfi and see how it does against my trans am.

My basic setup will be a 1990 corvette engine with a LT-4 hot cam, ported aluminum vette heads, the slp TPI intake stuff, edelbrock TES headers, Flowmaster catback, stock 5 speed with the 373 gears. So I'm hoping all this will be a decent combination

No this isn't meant as a TPI/CFI flame I just think technology is the way for performance but you gotta improve and run what you have right.

 

Thats all cool.. I remember when my 82 Firebird was new, I thought I was at the top of the world with that LG4. First V8 car I ever own.

But when I did the 350TPI transplant back in 98, I then realize how weak the LG4 was. But now I have a new problem.

With changes to my exhaust system back in 2003, I ended up moving my power-band up about 300 to 600 RPMS. With the new exhust configuraton, the engine wll now spin about 5000 RPMs. With the orginal configuration of my 350TPI motor power came in good around 2000 RPMs. Now the power comes in around 2500-2600 RPMs. I have an 1600 Stall convertor. Its a lot more powerful but it does not drive as well with light thottle like it once did. So I must move to a higher stall convertor when I transplant the 700r4 transmission.

Please no comment guys on my convertor problem. I going to post a new thread over in the Tranmssions section.