Patrick's Twin Turbo 350 Build Thread

Take your fully sssembled heads to the machine shop and let them decide what they need, unless you KNOW FOR SURE exactly what is going to be needed and what you want

 

Resurfaced your valves if your not going bigger.
Some cleanup porting in bowl with alittle of the valve guide milled and smoothed should net decent flow under pressure

 

I have done Fitech's on two 455's with D-1 Procharger's. Mine and Bobb Makely's. Bobb's is a Tomahawk block with Bulldog heads. Mine is all iron and so much stock stuff it is scary. For cars that do most of their time on the street get the EFI. I have never seen a blow through carb that was not being constantly messed with and never give you the street manners that you need. Don't see a lot of difference between the Holley Sniper and Fitech. Do an in tank system with a 340 Walbro. Use the fuel regulator on the units with return line. I do not like to skimp on the return line size. For ignition use an MSD 6530 and use it for timing control. I run and intercooler, Bobb doesn't. If you can run a single plane manifold. 400 hp at the rear weals is a realistic goal. Run a really high quality alternator. Forget the Braille battery and run an XS Performance.

 

I would just bring the heads to the machine shop for an estimate of work needed and then order stock valves from rock auto if needed. Let them tell you what needs to be done.

 

Thanks for the tips! EFI is the plan for sure. Probably Holley for the in-tank setup as well. TA SP3 all the way.

Couple of questions: How come you use the MSD box to control timing and not the built in timing control on the EFI (both the FITech and Holley have this ability)? That was one of my main selling points as far a tuning. Was going to use an MSD Streetfire box to keep it cost efficient.

Also, how come XSPower instead of Braille? I've never used either but have seen good reviews for both brands. I'm just tired of crappy parts store batteries that die one month after the warranty expires.

Got it, that's what I'll try! Hopefully this shop near me is a good one.

 

I use the MSD programming because you can get a more sophisticated timing curve. With boost you need a box anyway so just a bit more for the programmable model. The Braille battery works but there is not a lot of extra capacity in them. The size and light weight is nice but as more load was placed on the electric system it could not keep up. The fuel injection systems need really stable electric power to work reliably.

 

Got it! I will look into the MSD vs the Holley timing capabilities more. The MSD 6530 is about $250 more than the regular MSD box. I will also do so more research on batteries. Cam should be here Friday! I probably won't have time to work on the engine until next month since I'll be out of the country starting next week to visit family. However, I was able to get a decent amount of garage cleaning done. Still a lot more to do though! All those tools on pegboard were previously in different piles on the floor

 

Cam and lifters here a bit early! Now I just need to order a bunch of stuff from TA, including a new front cam bearing so I can install/degree this thing.

 

It's been a looooong time since I've updated this thread, but it's also been forever since I've had a chance to work on the engine! But with the way things are now, I've got a lot more free time and have been putting it towards the Buick finally.

Since my last post I have installed new dual-backrooved TA Cam bearings, a new neoprene rear main seal (though I probably messed it up, we'll see), and the camshaft/timing chain. I've also removed the heads to use my Comp Cams degree kit. Oh and I also cleaned all the carbon from the tops of the pistons with a wire brush, and used a shop vac to try and make sure nothing messes up the bores. Aside from the engine I also added some cross-bracing and a fuel cell to my run stand.

During this time I've learned that the pistons are .030" over and at least the #5 main is .020" undersized. So it's definitely been rebuilt, probably why it still makes good compression. Also I think it has the weaker non capscrew rods?

Here's the engine as it is now, I'll going to be posting another thread to ask for cam degreeing help!









Are these the less desirable rods?

 

Nope, those are the capscrew rods. Stud/nut rods are weaker, but lighter. capscrew rods are heavier but stronger. Not by a whole lot, but enough to matter. I'd get a razor blade and scrape as much of the head gasket material on the surface on the block as you can.

OR

Turn the engine upside down, bring the piston you'll work around to TDC, use a red scuff pad in your hand, and go to town scrubbing the block. Having the block upside down will prevent a large amount of the scuff pad particles getting into the engine.
Use compressed air, brake cleaner, etc to get any of the bits out, or before you scrub bring the piston almost to tdc and use some masking tape and mask off the bore and the piston.

 

Thanks man that's a good tip! The way I cleaned the piston tops was by having my girlfriend follow my wire brush with a vacuum, but I didn't turn the engine upside down. Then we vacuumed around the piston/bore a bunch. I also did razor scrape the old head gasket as much as I could, again right side up with the vacuum. Will do scotchbrite now too. I hope I didn't mess anything us by getting stuff into the engine? So from now on I should clean upside down, but will spraying brake cleaner/compressed air into the bores cause grit to make it's way past the rings?

Is there any way to really clean the bores without taking the pistons out?

 

You should take them out. You could hone it, install new piston rings, etc. It's the only way to ensure no grit is in between the rings.
They're numbered on the rods anyway, so you can't mix them up. the rod caps have a small divot in them for the bearing tang, the tang divots ALWAYS go on top of each other. plus with how the capscrew rod caps are shaped, it will be very obvious when a cap is backwards.

In short, i would remove the pistons and rods. Then scuff pad the cylinder deck with the block upside down. Clean up real good, clean up the pistons and rings real good, oil em up, then put your pistons and rods back in with new bearings since old ones have lost their "crush", then put oil on the deck surface to prevent flash rusting. You don't need to re hone if you can still see the cross hatching and you put the pistons back where they were, obviously.


Now, if not done already, before you put the pistons in, put in a dual groove TA front cam bearing. $15 and some time is worth it. you may be able to use an old cam to help guide the bearing in if you leave the other 4 alone. then use a spare bearing if you have one to center the bearing in the bore. it can't be flush with the front of the block, needs to be inset what... 1/16"?

 

There is nothing or there should be nothing IN the bores to clean, leave 'em be, you said it has good compression so obviously the rings are happy with the bore finish, don't piss off the rings LOL
It was a good idea to have your girlfriend help you clean the deck by following you with the vacuum, she's a keeper!
The only thing I'd use on the bores is a lint free rag and some WD40 and wipe 'em out, then you could rotate the crank to bring each piston to TDC then go a bit more until the piston starts going down, then stop. Doing this will push any carbon flakes/garbage to the top, the rings will act as a squeegee.
Engine looks good
Yes it has been "gone thru" once before by the number stamps on the rod caps, Im assuming you checked the rod/main bearings being you said the rear main was .020, or was it because that's the only one you removed to do the crank seal?
I would assume ALL the mains are .020 under, which is no issue.
How was your oil pressure before you removed the engine?

 

I have been avoiding removing the pistons and going the honing route since this engine already makes good compression, and as Mark mentions below I am afraid of "pissing off the rings"! I have a spare 455 I might try this on as an experiment, but when I bought this thing it made 150psi across the board after being warmed up on a stand. I'm afraid to mess that up!

You may have missed it in my earlier update, but I just finished installing TA back-grooved cam bearings in all 5 journals! I was originally going to just do the front but figured I may as well do it right and do em all. I was afraid of misalignment causing camshaft binding, but I went slow and tested the cam as I did each new bearing. It spins easily by hand with all the new bearings installed so I think my bearing tool works well! That and my camshaft journals are all aligned. I did find that I had to measure the location of the oiling holes front to back as they are offset towards the front IIRC. So I had to do some math to figure out exactly where to locate each bearing, but they all ended up sticking out of the front a bit except for #1. TA had a spec to install #1 0.125" - 0.130" (again if memory serves) from the front of the block, and I think I ended up going 0.120" based of my measurements of the front oiling holes.

Haha thanks, she's the first one who's been willing to help with and learn about car stuff, which is amazing!

Thanks for the tip about cleaning the bores, will do that. Also yeah I only pulled the rear main cap to do the seal, I figured no reason to disturb any other main caps if I could help it! Unfortunately my memory of the oil pressure is foggy (got this thing almost 2 years ago) but I'm pretty sure it made 60psi when warming up, have no idea what the hot oil pressure was. I do have a rebuilt timing cover ready to bolt on (done by UNDERDOG350), that with the new cam bearings I'm hoping will give good oil pressure, assuming bearing clearances were good when it was rebuilt.

 

Anyone have any advice about degreeing my cam in? I started another thread here:

http://www.v8buick.com/index.php?threads/need-help-degreeing-my-cam.356763/

 

HAHA Believe me if you HAD issues, you'd remember
Just keep doing what your doing, disturbing as little as possible.
What I WOULD do tho is check a few of the rod bearings, BUT, if you'd rather not I don't blame you, as the UPPER bearing shell is the one to check as it sees most all the load/wear, and you have to rotate it out of the rod and around the crank journal to remove it if your not tearing the engine down, its not hard to do, but you have to be careful.
On degreeing your cam, I've done mine numerous times, but to rattle off how to do it, I'd need the instructions in front of me
Others on here are more well versed, HAHA.

 

Following as well

 

Thanks Sebastien, I hope you're doing well! Were you able to sell of your Turbo 350 stuff?

 

h
No I decided not to. I kept everything and converting to Efi soon. Just waiting in my shop to be built.

 

Couple of small questions/updates:

I have two distributor gears, one from this engine and one from my parts engine (I have no idea which came on which) and they look different! Which should I use? I'm inclined to go with the one with chamfered teeth because it looks more friendly haha. They both appear to be in decent shape:





Also, which way does the fuel pump eccentric face? There is an "F" on one side so I would assume that goes towards the front of the engine, but you know what they say about assuming!



Check out the difference in wear between these two eccentrics, that groove is deep! Going to toss the bad one. Imagine all that metal in your engine



Lastly, spent the last two days cleaning the decks with scotchbrite and simple green with the engine upside down, thanks to UNDERDOG350 for the tip. Also cleaned one of the heads today in the same fashion. Going to pull the valves tomorrow and clean the backside as they are a bit gunked up, and replace the valve stem seals. I tested the valves on that head with brakecleen and got no leakage! Fingers crossed the other one doesn't leak either.

Here is where I was half way done cleaning: