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Bandook's 01 Imp, top swap-ified

bandook

bandook

Donating Users
Well, after just finishing replacing LIM gaskets in my na 01 Impala, I realized how easy it was and how much better the engine would look with an M90 sitting on top :) So...I've picked up almost all the parts for the swap. I will use this thread to consolidate my questions and hope you guys will be able to help.

I found a 99 grand Prix as a donor. What I wasn't able to pick off it I have found on order. M90 will hopefully be bought this weekend and rebuilt soon. The heads are at the machine shop and I'm waiting to hear how they check out.

I'm installing a fwi and speed daddy headers. I will mildly port the heads and intake myself. Basically just clean up casting marks and smooth things out. With these mods my questions are:

1. What size pulley should I start with? I will be getting it dyno tuned. Can I safely start with a 3.6-.5? I've seen members with same mods running a 3.4 but I think they had an l67 motor. With the higher compression of the l36 should I leave stock pulley on? I want to make the most of my money spent at tuner so I want to buy the smallest/best pulley for my current setup.

2. Talking to the tuner he highly suggested that I plumb in my IAT into the lower intake manifold. He seems to be a reputable GM tuner, and I don't want to doubt his strategy, I just haven't seen anyone do this. With my limited knowledge of tuning it kinda makes sense tuning the timing based upon the post m90 air temps, but I question things like heat soak and the iat fowling due to the dirty environment it will be in (the intakes I've seen are always full of carbon and oil). Anyone help me understand his logic?

Thanks for now. I'll keep you updated as I go.
 
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Re: Top Swap in progress, few questions

Putting the IAT into the LIM is something I've seen done on TBSS's when they SC them. I don't believe our pcms adjust fast enough to take that as a benefit.
 
Re: Top Swap in progress, few questions

BillBoost37 said:
Putting the IAT into the LIM is something I've seen done on TBSS's when they SC them. I don't believe our pcms adjust fast enough to take that as a benefit.
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I'm trying to make sense of this. What refresh rate would the iat need if in the intake vs. Stock location? I have an extra IAT so I think I'm going to put one in lim and leave the stock one in too. Then ask him to tune it in both locations for a comparison. That way I can have some solid data either way. Perhaps he has some trick up his sleeve that hr is able to pull off a better tune with it in lim. His exact words were "I would highly suggest getting a IAT sensor plumbed in the lower intake manifold so we can pull timing based on IAT temps."
 
Re: Top Swap in progress, few questions

Do you have a way to monitor for KR? If not, then I'd start with the stock 3.8 pulley. You don't want to drop pullies on something that you have no way of seeing how much KR you have right off the bat or you'll be chipping pistons in no time, especially with the higher comp. Are you going to use a GTP ECU or modify your GT ECU?
 
Re: Top Swap in progress, few questions

FordMan77 said:
Do you have a way to monitor for KR? If not, then I'd start with the stock 3.8 pulley. You don't want to drop pullies on something that you have no way of seeing how much KR you have right off the bat or you'll be chipping pistons in no time, especially with the higher comp. Are you going to use a GTP ECU or modify your GT ECU?
Click to expand...

Yeah I have a scanner. I use torquepro with Bluetooth obd adapter. That's how I learned that adding a fwi reduces knock. I was seeing up to -5 , now rarely see -1.

This is an 01 impala, stock l36. It will be fully tuned. Tuner will flash my pcm well enough to get 30 miles to his shop. Then he will dial it in there.

How are guys pulling off a 3.4 with such minor mods?
 
Re: Top Swap in progress, few questions

Does this exhaust valve look usable to you? This is after cleaning it up. Should I just get new valves or try to save these?

Its pretty rough, but can't say I've seen enough to know if its too far gone. Intake valves look fine though.
 


Re: Top Swap in progress, few questions

if thats pitting its trash.

if its not pitted you could try lapping the valves. search you tube for lap lapping if you dont know what that is. its pretty simple. your just using a paste compound to grind the valve to the seat in the head, this way they mate up nice.
 
Re: Top Swap in progress, few questions

id just order them from rockauto or some other vendor before over paying at zzp.

and you should lap the new valves for sure.
 
Re: Top Swap in progress, few questions

Started some work on the throttlebody last night. First thing was to put it on an immediate diet. First time I saw that hump I knew it needed to go.


Then I cleaned it up a bit and painted. Don't know exactly how the paint will hold up to the temp swings, but its certainly better than it was.


Now I just need to find the screws to the butterfly... :(
 
Re: Top Swap in progress, few questions

Picked up the m90 last night


Five minutes later it was opened up.


Its in good shape. The case has some minor scratches inside, most likely from sloppy needle bearings. So I'm ordering new needle bearings and snout bearings. Wish it was easier to replace the front case bearings, but I imagine they will be OK. Now I've got to decide if I am going to purchase a press or trust a local garage to press them in right. I'm always nervous when someone does my bearing installs. I might ask a local guy to rent me some shop time and just use his press. The place that's doing my heads could do it but I can only imagine what they charge.

I'm going to open up the inlet and clean up the outlet on the case, and of course clean it up and paint it. Still undecided if I'm going to plug the silencer ports. If I do I have some ideas that doesn't involve jb weld or epoxy. I've yet to see conclusive evidence that it makes the blower louder or more efficient. If it was guaranteed to make it as loud as a Whipple I wouldn't hesitate.

The m90 came with a throttle body, so if anyone needs one let me know.
 


Re: Top Swap in progress, few questions

If your tuner cant get it perfect without it being on a dyno find a new tuner.... you can get a zzp pcm for 100 bucks and not have to mess with it.
 
Re: Top Swap in progress, few questions

darkhorizon said:
If your tuner cant get it perfect without it being on a dyno find a new tuner.... you can get a zzp pcm for 100 bucks and not have to mess with it.
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Where do I get the pcm for 100? On zzp's website it's 200.00 for top swap tune. And I have ran across many different opinions of zzps tunes, which kinda steered me away. However I'd love to get a good tune for 100! I could throw the extra money at rockers or something. :)

Got the case pretty well cleaned up.



Looks better than I hoped, which is good. When looking at it through all the carbon it makes it looked pretty scratched, but its not. Just the bottom had a couple deeper ones, most likely from the bad needle bearings letting it drag a little.

Rear valve cover, L67 injectors and valve seals came in. Though now I've been thinking I want to get 60's for e85. I would for sure need a different pump, I don't trust the cheap aftermarket one i just put in. What is a recommended fuel pump? All I've heard talk about is Walbro, but I definetly don't want a loud pump.
 
Re: Top Swap in progress, few questions

So what's left as far as the topswap goes what other parts are needing


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Re: Top Swap in progress, few questions

REDCOMPG said:
So what's left as far as the topswap goes what other parts are needing


Sent from my iPhone using Tapatalk
Click to expand...

All L67 swap parts I have. Well, except balancer but I'm ordering a new one. Still waiting to hear about my heads. If they don't check out I'll have to find another set and send those back in. Gaskets, headers, bearings for m90 will be in this week. Ordered a few things from zzp: mps with 3.4, wiring, rocker bolts. Have a few things from amazon I'll probably order tonight: idlers, head bolts, balancer and misc bits.

I was hoping to do the install in two weekends, but just found out we're going to cousins bday party that weekend. Kind of a bummer but at least Russians know how to party so it should be a good time :) So probably install first weekend of May. Unless I can't stand looking at a table of parts and take a day or two off work.
 


Re: Top Swap in progress, few questions

99GT2dr said:
$200 for a "top swap" tune? Wtf?
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Yeah... They charge an extra 75 for it being a top swap. Its all good, just makes the 400 dyno tune look less costly. Still haven't quite came to the conclusion that moving the iat into lower intake is a good idea. Wish someone could help me understand this logic. Everything I've seen on I at either has folks moving it closer to filter, or closer to throttlebody. I guess as long as the tune has it reasoned into the new location it shouldn't matter. I can see it being more useful under the blower because of the (in)efficiency of the m90.

Its just funny that there are talks of moving it closer to COOLER air, near filter. On an untuned car all this would do is cause the computer to lean out the fuel trims, right? So it seems it would be better to get the warmest reading right before its combusted. Which kinda backs up putting it into the LIM. Am I tracking right here? If the computer is reading cooler air than what is entering the combustion chamber, that's gonna cause it to run lean, which creates detonation, which causes the pcm to pull timing. That's why the tuner said he wants to base timing on the LIM air temps?
 
Re: Top Swap in progress, few questions

I think you're looking into the iat sensor too hard, don't have my laptop handy to look at the table, but it really doesn't pull much timing in the extreme hot/cold ranges that it does. I zero it out completely, less variables when trying to control your timing. We know the outlet temps are high, if that's a concern get an IC, lol.

Regardless of the outlet temps, you start with stock timing and add a degree or two at a time until you start seeing kr, then back off .5 at a time til it's gone. Whether it's 10* or 1000* outlet temp, it's still gonna get tuned the same way, you just won't be able to add as much timing the hotter the temps are.
 
Re: Top Swap in progress, few questions

99GT2dr said:
I think you're looking into the iat sensor too hard, don't have my laptop handy to look at the table, but it really doesn't pull much timing in the extreme hot/cold ranges that it does. I zero it out completely, less variables when trying to control your timing. We know the outlet temps are high, if that's a concern get an IC, lol.

Regardless of the outlet temps, you start with stock timing and add a degree or two at a time until you start seeing kr, then back off .5 at a time til it's gone. Whether it's 10* or 1000* outlet temp, it's still gonna get tuned the same way, you just won't be able to add as much timing the hotter the temps are.
Click to expand...

See, I figured I was missing something :). Could you possibly find out how much timing it pulls at x temps? I'd like to have more info about this before I commit to drilling a large hole in my intake.
 
Re: Top Swap in progress, few questions

If nobody else gets to it before me, I'd be happy to. Not sure how set you are on the dyno tune, but that price seems close to what an hptuner suite costs, being able to do your own tuning sure comes in handy. I've had my powrtuner for a very long time, would never consider giving that up, lol.
 
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