alright. the V6 that we're talking about is an '89 2.8L. The timing chain skipped teeth, so obviously that means new gears and a new chain. but i can't shake the feeling that the valvetrain is probably damaged. the pushrods look ok though, so its most likely the valves, unless i'm wrong. the car isn't running so i don't have a lot of info on performance. it has fuel pressure and spark. it backfired when i would try to turn it over, but since i've started taking apart the engine i'm obviously not trying to start it.
so here's the question. what's a good idea for heads on these engines? just a valve job on the stock heads? keep in mind i don't have a lot of money to spend on this.

 

There is a great possibility that you have a few bent valves. A valve job isn't gonna fix that; you'll need to replace some.

It's time to go junkyard hunting. You can use heads from any fuel injected 2.8/3.1/3.4 rear wheel drive (S-10/f-body) or the 2.8 fiero. They are all the same. Also the Isuzu rodeo if it had a 3.1 Throttle body injection engine.

You'll probably get a good used set for less than the cost of a couple of new valves and a valve job!

 

well, i was assuming that we all knew that valves would need replacing. i was talking about improving performance cheaply

 

No such thing for the 60 degree V6.

The closest thing to budget top end is the front wheel drive parts swap that I see in progress from firstfirebird. I have yet to see one actually running...

When they iron out that system, things will get better, budget wise. Unfortunately, you can't do it with your engine because you have to use an oil pump drive instead of a distributor and then find another way to get a cam/crank signal to run the coil pack ignition...

 

do a compression check once u put the chains and gears on, may buy u some time to find good performance

 

So mine that I had running for over two years and close to 30,000 KMs, wasn't "actually running"?

I did that over 5 years ago, with a 2.8L block, small port 3100 top end (wish I had just went ahead and used the 3400 top end I had sitting beside it instead of "saving" them for another project that didn't happen), FWD 3.1 crank, small T3 turbo, etc, etc.
I've made several posts about it in the past, it works, and works well. The thing that would have really improved the outcome would have been tuning the ECM, and using larger fuel injectors. I didn't have a whole lot of money at the time and couldn't afford those two last parts to the puzzle, now that I have better parts and tuning equipment the outcome will be even better.
The only reason I took it apart was because I thought the turbo was bad (turned out to be the inlet gasket), and decided that while I had the turbo off for an upgrade, I would also upgrade the top end. Then I bought a buisness and had no time to work on it after that, until this year.

 

Where did you get your crank signal to run the DIS? I'm sorry if I put down your project; I didn't mean that...

I just haven't seen the rear drive blocks except the 3.4 run a DIS...

 

External trigger. Custom made by my Grandfather with some design input from me.

 

The DIS was my biggest holdback from even starting mine, but when I spun a rod bearing from detonation the 3.4 block was the best route for me to take (fuel-cut for rev-limit , also attributed to lack of tuning on my part).

Six, when did you first do the swap? I know Russel did a Gen2 top end in 2001 and upgraded to a Gen3 in 2003 IIRC, but again his was easier on a 3.4 block/car. He chassis dynoed 191hp and is still running with a stock tune last I heard from him (and has since put in a cam).

I have yet to see anybody besides mine and the other engine I'm building for someone else that used a 3500 top end and Camaro pistons.

BTW: GrimmCS (bought my old turbo kit) has found a reluctor wheel that gets bolted to the front of the dampener. He is also installing a MegaSquirt, so it may be a product meant for it, haven't aksed.

 

Got any pics of that setup? That alone would allow us to all jump on the front wheel drive top end band wagon...

 

i forgot about external triggers! aren't they magnetic?

 

If Russel is who I think it is (94camaro IIRC), then his was completed shortly before I did mine, I added the hair dryer to mine though. His wasn't a genII top end, it was a small port genIII (3100) again, if it's who I think it is.

 

Yep, posted those pics several times, and even enquired about desirability for people wanting a similar product.

This is pre notches cut/smoothing of the bracket:



Here it is after break in, so it verified it works! :


I ran this through two years, including harsh winters, and never once had an issue with the ignition system. I was worried about the sensor being exposed to the elements, but it was fine. If you drove through a large cloud made of metal particles, you may experiance some issues though.

I would do it a bit different in the future though, as the way the bracket was made, I had to hammer in the front of the oil pan, to clear the bottom of the bracket. It worked this way, but would not be what I would design for a production piece.
----------
Most aftermarket crank triggers are not, the magnet is in the trigger wheel. The OEM GM set-up uses a maganetic sensor though.

 

i have a complete 2.8l v6 from a 89 camaro ran when i pulled it to start my turbo drag setup. has tranny too. id sell it for 250.
motor and trans. i drove the car home so i know how it ran when it was installed.


here is the car it came out of;

 

I am not planning on installing MS. First I want the car to run and be reliable, plus I dont really understand all the computer stuff. I was planning on finding someone who can put the turbo 3.1 code into my ECM. Mabye after I get it working right and have the need for more boost Ill go down the MS path. Havent really got this far yet though.

 

Do you have a '7730 or '7727 ECM?

 

He said it was a Gen2, but some people get confused between the Gen3 small port and Gen3 large port as two generations.

Yes, same Russel. Calls his car "Elanor". It's a black early 4th gen fbody.

Him and Tiago flowed the small port heads and some $900 ported iron heads. The irons flowed 158cfm int/ 142cfm exhaust and the unported "small port" flowed 162 cfm int/ 139 cfm exh all at .500" lift. Ben flowed the stock 3500 heads at 218cfm, also at .500" lift. The aluminum Gen3 top ends are capable of .750" or so (roughly measured) but the inexpensive LS6 springs will only allow .580" or so without modifying the seats. (I'll get some accurate measurements when they are finished being assembled)

The 3400 heads ported to FelPro Problem Saver actually flow better then the ported 3500 heads, only because the metal/rubber intake gaskets won't be available until March for the 3500. As of now, you have to get the 3500 gasket set from GM, BUT the UIM gasket included is much larger then the FelPro UIM gasket. The larger UIM gasket allows the runner to be opened up at the top to increase velocity, and allowing even bigger porting on the head side. Needless to say, I can't wait until March

We are also building a flow bench at the shop, and we can accumulate more data, more details to come later.
----------
IIRC all the 3.1 Fbodies come with the SD '7730.

I would also be interested in the DIS mod to the '7730. I have read that you need to do a few re-pins, but the ICM is looking for the same signal from the ECM as the HEI does. (5v referance, correct?)

The only hang-up I have with that is I have a MS unit already, and no burning equipment yet.

 

who said the ported 3400 heads flow better then the ported 3500 heads?


I'm expecting 250-260CFM from the intake ports whenever i get the time to take them in....

 

I'm going on Ben's data. Did you open up the gaskets?

 

Who swapped a dohc 3400 into a camaro? I thought that was russel...

 

Yep, same Russel, he did indeed start with a small port genIII top end, just as I did.

The "DIS mod" is not difficult, at least not on the PROM side, essentially once the genIII top end is on the engine, you can use the same bin file that would be used for the hybrid swaps or even full 3400 swaps that are used in the J-body swaps. I'd have to look at both wiring diagrams to know for sure, but I don't recall any pin swapping being needed.

Yes, the signals between the ICM of both the dizzy and the 660 DIS ignition are essentially the same.
----------
AFAIK, that car was never finished. I only recall seeing preliminary test fitting pics of it.
----------
I just noticed tonight how the exhaust ports were changed between the 3400 and 3500, to promote smoother flow after the valve guide. Also the ports are seperated a bit from the 3400 to 3500.

 

These iron heads you're referring to, are they with the small or large valves?

 

Damn, that looked like a sweet setup.

 

Of course, one would be crazy to spend $900 on the old carb heads.

To show you the difference between the iron and AL heads check out these threads...

https://www.thirdgen.org/forums/v6/4...t=#post3329697


https://www.thirdgen.org/forums/v6/4...t=#post3419830

 

Wow, talk about a thread Hijack...lol

If the Chain skipped and the vehicle ran fine before the chain problem, then the heads and valves are fine. Our engines are non-interference, so unless you've done some serious head milling and put in domed pistons then there is no way for the valves to hit the head, there's just too much room.

The reason for the backfire when you tried to start it was because the valve timing was off. when you install a new chain, everything will run as it did before.

 

I have the 7730 ECM. We could move this to my "Man Down" thread to go further into it.

 

Well worse things have happened, ha ha. I did a very quick port and polish on the older small valve heads in school (for a project) and almost hit that number which is why I asked. Despite leaving room for improvement, I still gained over 20cfm of flow. Are there flow charts for each of the different heads somewhere?

 

Not everyone is willing to share their charts, lol.

Once my flowbench is complete, then I can share more info.

Can you imagine what you can do with a set of heads that START flowing at 218cfm (intake)?

 

I ment the stock flow actually, sorry for the confusion. Just curious how they compare (or not ha ha) at the different lifts and such was all.

I would love to swap over to the 3.9 setup (sounds like there's impressive numbers there), but the swap to DIS sounds a bit involved especially since my source for ECM tuning says he doesn't have access to a definition file. Long story short, I'm still trying to figure out how I'll build mine. Is the only reason for going to DIS because of the intake manifold design? It looks like the 3.9 might have clearance for a distributor...

 

DIS swap is not that difficult and the def files are available for free from moates.net, among other sources.