Hope I'm in the right spot. Few engine questions.

[WhoIsThisGuy]

Sorry for no intro but between my job, and this project I'm short on time.

Long story short a good friend of mine's dad was just diagnosed with cancer, doesn't look great hence my urgency. Years ago the dad taught me how to build an engine, and him and my friend have done everything on cars, except that. So I'm going to make that happen one way or another.

Due to time constraints we settled on a 2.8 because we have one (40k miles). At this point we just want to build an engine. We do plan on doing turbos down the line, so I'm donating an extra Haltech to the cause and an e-throttle. I have tried to do as much research as I can but I'm still left with a few questions, ones I'm sure have been asked a thousand times before, but I just haven't found the answers. I will keep looking and will cross post this to v6z24.com. We're not chasing big numbers, just want to build a memory, and do a few neat things to it when it goes in the car, (88 Sunbird).

My first thought was making the engine breathe better by doing the 3100/3400 head/intake swap, but as I understand it this will send compression through the roof?

I keep seeing references to not crossing the 7psi threshold when boosting. I'm curious how that number came about. Is there a weak link to the engine that limits it? Tuning issue? Oiling?

I only work on Japanese engines, so I don't know which is the best route for a rebuild kit. New bearings, rings, etc. Open to the idea of a different cam and springs, but again, we're more concerned with making the memory than the engine itself. So if I can't source that bit in time we'll work with what we have.

Thanks for your time, and apologies for being blunt, and if this is in the wrong spot I truly am sorry.

This Guy

[SappySE107]

You already have aluminum heads, so the compression won't be high. I think you are reading about iron head 2.8s and not aluminum head. You have a gen 2 motor. Iron heads are gen 1. 3400 is gen 3.

https://www.60degreev6.com/vb5/articles/-1987-1994-aluminum-head-mpfi/424706-gen-2-to-gen-3-top-end-swap

No idea on rebuild kits. I source all my parts individually because all the kits I have seen are cheap garbage.

[WhoIsThisGuy]

Awesome, I really do appreciate the info, in my reading I kept getting confused as to what engines they were talking about. So a trip to the junkyard is in order then, and thanks to you 1/3 on the way to getting this done.

From the bottom of my heart, thank you.

[SappySE107]

I have performance parts on wot-tech.com, some of which I would consider for a turbo, but none of which you absolutely must do. ARP rod bolts are high on the list. MLS gaskets, mostly to go thinner for quench. I prefer the timing sets I sell because they are an OEM chain. I would use an M134a melling oil pump as well. It uses a 3/4" inlet vs 5/8". Not use high volume or pressure version. A 2.8 with a 3400 top end on it should be a lot of fun even without a turbo.

[WhoIsThisGuy]

I have performance parts on wot-tech.com, some of which I would consider for a turbo, but none of which you absolutely must do. ARP rod bolts are high on the list. MLS gaskets, mostly to go thinner for quench. I prefer the timing sets I sell because they are an OEM chain. I would use an M134a melling oil pump as well. It uses a 3/4" inlet vs 5/8". Not use high volume or pressure version. A 2.8 with a 3400 top end on it should be a lot of fun even without a turbo.

Oh wow, I remember your site from a long time ago, same buddy showing me something, forgot all about it till now. I think you might have an order soon. Do you recommend different springs with your turbo cam?

Appreciate all the info. Thank you!

[SappySE107]

The stage 2 springs are a drop in for the stock seat/seals on the 3400 heads, and will handle at least 14 psi. The stage 3 springs would be my choice for an all out build for more boost, but I would also use the ls style seat/seals because the springs ID rub on the stock seat setup. Stock springs are no good for boost.

[WhoIsThisGuy]

The stage 2 springs are a drop in for the stock seat/seals on the 3400 heads, and will handle at least 14 psi. The stage 3 springs would be my choice for an all out build for more boost, but I would also use the ls style seat/seals because the springs ID rub on the stock seat setup. Stock springs are no good for boost.

Awesome, I really appreciate you getting back to me. Will definitely be getting the springs as well.

Making some progress now, feels great!

[WhoIsThisGuy]

The stage 2 springs are a drop in for the stock seat/seals on the 3400 heads, and will handle at least 14 psi. The stage 3 springs would be my choice for an all out build for more boost, but I would also use the ls style seat/seals because the springs ID rub on the stock seat setup. Stock springs are no good for boost.

So sorry to bother you again, and I really hope this image resizes itself. All I can find, just using amazon as an example cause it came up in my search, I can find a Melling M134, but I can't seem to find anything that says M134a. It looks right, but hoping to make sure.

One more thing, putting together my list from your site, might as well go with stage 3 springs, awesome value! Are your seats and seals the LS style you mention? I might be sabotaging myself and causing confusion cause I'm looking at the cams under your 2.8 section, and moving to the 3100 section (3100) heads for the springs, seats, and seals.

[SappySE107]

Its just M134. I bet I was thinking R134A for air conditioning. Make sure you get a pickup tube to go with it. 251S.

https://www.wot-tech.com/product/valve-seat-seal-set/74

Those in a .553" guide OD for the rocker rocker arm gen 3 heads.

[WhoIsThisGuy]

Its just M134. I bet I was thinking R134A for air conditioning. Make sure you get a pickup tube to go with it. 251S.

https://www.wot-tech.com/product/valve-seat-seal-set/74

Those in a .553" guide OD for the rocker rocker arm gen 3 heads.

We're tearing it down today to get our measurements. Thanks for the link to the seats/seals!

That turbo cam, what kind of RPM are we looking at with it? That's just out of morbid curiosity. Also wondering what temp spark plug you suggest. Generally anything getting boost I go with a cooler plug. You have a ton of experience with these engines, so I'd value your input on what you'd suggest. Granted it won't be running for a bit, but need something to put in those holes, and it might as well be the right plugs. Also, for the conrod studs, and head studs, just go with ARP's specs? Seems like a no brainer, but every engine is different, had one engine that didn't like their specs (finicky little motor) and it didn't end well, and I value those with experience. Not their fault, it was just a goofy deal.

I appreciate all your help and am looking forward to ordering from you. Very squared away shop, and you've been a massive help.

Edit. I don't have the 3100 heads yet, so I can't check rocker ratios. So with the 3100 heads, do I stay with the 2.8 pushrods, and rockers?

[SappySE107]

Somewhere between 6-7k RPM. Until you boost it, stick with stock plugs. 1 step colder is a good start once you do add boost. I like the iridium plugs the 3500 came with (2005 G6 3.5l) as a starting point. Keep the gap around .050" NA and less with boost. Might take some trial and error but id start at .045" once its boosted. Not sure what you mean by ARP specs. You wouldn't torque stock stuff to ARP torque spec. The 3100 is 1.6 ratio, stamped or roller fulcrum. You will use the 3100 rockers, and a custom pushrod would be a good idea to measure the pushrod lengths you need. Roller vs Flat Tappet lifters so its going to be closer to the stock 2.8 pushrods but probably not identical. Since its not an adjustable rocker, you will need custom length pushrods to set the optimal lifter preload. If you have the roller fulcrum rocker, you won't use pushrod guide plates, and won't need hardened pushrods.

[WhoIsThisGuy]

Somewhere between 6-7k RPM. Until you boost it, stick with stock plugs. 1 step colder is a good start once you do add boost. I like the iridium plugs the 3500 came with (2005 G6 3.5l) as a starting point. Keep the gap around .050" NA and less with boost. Might take some trial and error but id start at .045" once its boosted. Not sure what you mean by ARP specs. You wouldn't torque stock stuff to ARP torque spec. The 3100 is 1.6 ratio, stamped or roller fulcrum. You will use the 3100 rockers, and a custom pushrod would be a good idea to measure the pushrod lengths you need. Roller vs Flat Tappet lifters so its going to be closer to the stock 2.8 pushrods but probably not identical. Since its not an adjustable rocker, you will need custom length pushrods to set the optimal lifter preload. If you have the roller fulcrum rocker, you won't use pushrod guide plates, and won't need hardened pushrods.

Appreciate the info on the plugs and heads, ignore my brainfart.

Would your adjustable push rods suffice for this? The "Adjustable Pushrod 5.800" - 6.800"" in the 2.8 section?

So far as far as your site goes, I've got the turbo cam, springs (stage 3), seals/seats, lifters, timing chain, mls head gasket, arp head studs and con rod bolts, and cam bearings. If those push rods work I think we're set as far as the top end goes?

Getting excited, oil pump arrives today, downside is I tore everything down yesterday which means cleaning, least favorite part.

Edit: Nvm found the preload info here https://www.60degreev6.com/vb5/forum...stable-pushrod