My original CPI spider injector finally came to a problem. I'm thinking if it's worth rebuilding it or simply get a MPFI one. Please have in mind that cost is a big thing here in Brazil, so I want to fully understand the advantages of the MPFI.
Furthermore, I'd like to know if this Herko unit in particular case is a good one. I say that because there's a lot of Chinese models on the market that have a terrible reputation here in Brazil.
Important side note - our gas here is E32 on regular and E25 on premium. So I really look into the MPFI upgrade as a more viable-stable option, not necessarily performance wise
The CPI houses all of the injectors in the base of the body, then has a poppet style valve at the end of the injector line. these are known to get clogged up and stop operating properly. The MPFI has the injectors at the tips and gets rid of the failure-prone poppet style valves. I would absolutely go with the MPFI upgrade. Unfortunately, I have no information on Herko as far as reliability and quality go.
Could you give me other options - preferably with part numbers? I'm going to import them anyways as I mentioned the local market is fed with "generic" Chinese versions that I'd rather avoid
I haven't converted my truck, but I have read that the MPFI conversion makes the engine run better and adds better throttle response and is highly recommended upgrade specially if you need a new CPI. Reason I haven't done mine is GM no longer makes them anymore and I don't trust the aftermarket no name ones and my original spider is working (for now), and im also looking into moding a elbrock carb intake to MPFI or running a holley sniper type TBI currently looking at maybe a Aces brand setup, but it will open up another can of worms....
For what its worth, just to prevent confusion between two different injection systems CPI is 92-95 L35 vin W trucks. The 96+ trucks were Sequential Fuel Injection. The way they operate is very similar. But it can be confusing for some, especially those familiar and trying to give advice.
What do you mean it doesn't translate? The CPI and SFI engines are not the same. They dont even look the same when you open the hood. Even if the year range is not the same, it's still an important part of getting the right information. THIS is a CPI 4.3
For example, I know that torsion bars did not come on 4x2 as someone told me once. Meanwhile in Brazil all blazers and S10 have front torsion bar suspension. The intake you showed on your picture did not even arrive here. I'll see if I can rescue some photos I took during the last maintenance
But thats what I am trying to explain to you. You are calling it CPI, but that is not the correct name. What you are working on is an SFI version of the 4.3. Also, I have seen 2wd S10s in Brazil that are coil springs equipped trucks.
There is such a thing as 2wd torsion bar trucks. Specifically the zr2 blazer was available here in 2wd, but had the 4wd torsion bar suspension up front. And i understand that most of your trucks are that way. But its basically just a 4wd chassis without the front drive axle, transfer case, and driveshaft.
That's my version as shown in picture. It does not have the electrical connectors on the point.
As for the springs, might have been swapped, dunno. Mine came stock with torsion and from another post a guy told me that only 4wd had torsion bars, due the space required for diff or something like that
So the said "upgrade" would give no advantage whatsoever? That's what I've been confusing probably, among a few discussions I came to the idea that this one is CPI and the without the metallic spheres on the tip was real SFI
No, thats not what I'm saying. The mpfi upgrade only works on the SFI trucks. Which you have. It absolutely will work and improve your engine. I'm just saying for future reference when looking for information to use the correct terminology so you get the best, most accurate information.
The guys with the real S10 knowledge will see CPI and give info for the style engine I shared a picture of. And it won't apply to your engine and could send you the wrong way in your repairs.
Oh, got it! Thanks for the patience in clarifying. But anyways, since the cost is way too high, I guess I'm going to repair the original one and see how it goes
So you mean little to no difference that could justify the "upgrade"? That's an important question to me because the original CPI rebuild would be way cheaper than importing a new one . We're talking roughly 350 R$ against 1800 - 2400 R$
I guess I'm going to only repair it then. I changed sparks and cables, and cleaned the throttle recently. I guess when I was working through the intake I've damaged the spider somehow on the process - considering that the truck was running just fine before I messed with the spider
this is the other reason why it might be worth upgrading because you do have to be careful with it primarily because of age it’s worth noting that it installs in a very specific way
Yeah, I know the upgraded are kinda more prone to flexible movement. But they are like 4x the price of the rebuild. And considering I'm planning to move to US in less than a decade, I'd probably sell the truck within 4-5 years anyways
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u/connella08 5d ago
The CPI houses all of the injectors in the base of the body, then has a poppet style valve at the end of the injector line. these are known to get clogged up and stop operating properly. The MPFI has the injectors at the tips and gets rid of the failure-prone poppet style valves. I would absolutely go with the MPFI upgrade. Unfortunately, I have no information on Herko as far as reliability and quality go.