And it gets mighty hot in there real fast. I don't think my fiberglass hood is gonna like that too much. Might also have to invest in an oil cooler and maybe a bigger radiator. Those turbos blow pretty good once things get warmed up. When I first started it they didn't blow anything hardly. I was getting worried that they weren't gonna work, but after it got hot they started blowing good. One problem though. When I shut off the car it likes to backfire through the carb. Is that because of the extra backpressure or what? Other than that it was fine. It ran fine when I parked it now it backfires, almost sounds like it wants to start dieseling. My temp gauge is reading good. The fan comes on when it's suppose to. Guess I'll have to play with timing or something.

Brad...

 

how long are you idling the motor for before shutting off?

should be at least 30 seconds.

 

Not a lot of info, but, is it doing this after takeing the car out for a test drive? Under boost?

sounds like the combustion chambers are getting too hot.
Some causes are detonation, spark plugs too hot (heat range)
lean fuel mixture while under boost. Richen up the secondary jetting. Being too rich is not a bad thing. Start your tuning RICH!.
Too much ignition timing while under boost.
On a turbo motor you have to retard the timing to avoid detonation while under boost. The amount of retard needed, and at what boost level its needed is dependent on the grade of gasoline used (octane), the compression ratio of the motor,
the amount of boost produced. And the A/F Ratio.
Generally a street turbo motor with 8 psi boost should have a compression ratio of 8.5:1 or less. This will need about 4 to 6 deg
of ignition retard while under boost.
In your case I'd say its a combination of Too high compression
(vortec heads on a flat top motor = 9.5:1 +)
too much timing, back er down to 24* total till you get a boost retard . get cooler spark plugs. And richen up the carb.
Is your fuel pressure referenced to the boost pressure?

This back fireing through the carb when you shut it off is a warning that something isn't right.
The motor is getting too hot inside.

Because your compression ratio is higher than it should be
for a non intercooled turbo motor on street gas you'll need to use water (water/ methanol) injection to allow a decent amount of boost without exessive ignition retard and no detonation.
It's easier than it sounds.

Sounds like your going to need some engine guages to know what is going on in the motor.
A boost guage, O2 sensor(AFR guage) , exhaust temp guage
and fuel pressure guage would be nice as a mininum...

 

I only started it up for a while. I don't have the bonnet yet, or my fuel pump yet. I just wanted to start it up and see if everything was working before I went ahead and bought more stuff. I will be getting a boost gauge and an O2 sensor and a fuel psi gauge. I'll be ordering that from Summit after I type this. I had my idle set way too high, that's why it kept running/backfiring when I'd shut it off. Doesn't do it anymore. A friend came over and wanted to see it, so I started it up again and turned the idle down. How effective would an EGT gauge be on a log style exhaust since I can't really put it in individual cylinders. Here is a pic of what I have so far.

 

On a turbo motor your ehaust and exhaust side of the turbo will give off a lot of heat. Especially during and after a hard run under boost. You should get some exhaust wrap and turbo wrap
an or some turbo heat shields.

Your non turbo specific camshaft timing is causing contributing to the turbos to be hotter too. Hotter than they already need to be.
The exessive overlap and exhaust duration will alow the turbo to push unburned fuel through the motor and into the exhaust system while under boost and low boost conditions (high cruise).
Over scavageing.

The remedy is to get a new camshaft with less overlap and less exhaust duration. wider lobe separation.

A low restriction big exhaust system after the turbos helps a lot too. Bigger is better when it comes to turbo exhaust systems.

 

A egt guage will be very effective mounted on the log.
I would mount it right in front of the middle 2 cylinders right on top of the log. I would put one on each side.

I believe EGTs should be about 800-900 deg at idle and cruise
and not exeed 1400deg under high boost.

Over scavageing : exessive exhaust duration and overlap
will increase EGTs.

Good pics

Looks like you're doing a A-1 job so far...

 

bhaas
Can't give much technical advice here, but a little compliment wouldn't go amiss here!
That looks awesome! That is SOME work! Keep us all informed.

:hail: :hail: :hail: :hail:

Andy.

 

smog cams can work well with forced induction... see if you can work a deal on an unused one that has been changed from a crate engine.

 

Thanks F-Bird and Andy, I appreciate it. I got a few more questions before I go and order a bunch of stuff from Summit. I'd like to have a fuel pressure gauge in my car. They are spendy. I'll be using a mech. fuel pump. Will this work? Part # atm-3313 inside mount with isolator. WTF??? A/F meter #atm-4475 does anyone know if it comes with wiring? Rods and jets for an Edelbrock carb. Does Summit have them? Not in the book so I'll have to call for those. Cam? I will get another one I guess. The one F-Bird mentioned in another post probably from AMOTION. It's gonna suck pulling that oil pan. Nevermind. I just remembered I put a 2 piece timing cover on. YES!!! That's a load off. Anything else I might be forgetting? Phil, I had it idling for a couple of minutes before I shut it off. Thanks. Also, anyone know what sizes the stock fittings on the stock fuel lines are? Are they AN fittings. One line is 5/16 and the other is 3/8. 2.8L V6 lines. Here is a good site for EGT gauges.
http://www.aircraftspruce.com/catalo.../micro1egt.php

Brad...

 

Very nice looking bhass.....finally someone who completes their setup and makes it look nice.

i told you those logs would look/perform nice

keep it up

 

Thanks 89, looks like I'll be changing the cam to. I'll either call AMOTION or CompCams tomorrow. Figured I've gone this far might as well no screw it up not having the right cam. The track around here opens Feb 2 last I heard and I'm way ahead of schedual. I still gotta put my 9" in there. Is there any problem with having that pinion off to the side a bit? That's the only concern I have with that 9". I also ran the exhaust off my turbos into my pretty much stock Y pipe exhaust. Is that gonna hurt me?

Brad...

 

awesome looking engine bay pics!!!

 

Most likely, i would imagine

 

Wow, if my engine bay looks half as clean as that when I'm done, I'll be amazed! Nice work man, keep the pics comin...

Cheers