430 Overhaul with TA-212

Background:


I've removed my Riviera 67 430 engine for a "spray can" engine overhaul: ball hone, re-ring and bearings changeout. Engine was unmolested standard, with 88k on it (no broken gear teeth's found on pan!). Pistons had some pitting from detonation but measured all good otherwise, no cracks, etc.

Modifications: some basic head porting (throat / "3-angle" valve job), front grooved cam bearing, TA-212 cam (installed with new stock springs), B4B. The timing cover looks good, will blueprint new oil pump, seals, etc.

The let down: The so-called "10.25:1" engine has pistons 0.055-0.06 down the deck and with 0.041 Felpro head gaskets, it has a measly ~9.03:1 compression. Quench is terrible and I need some advice on heavy cay / cam advance / low DCR / etc combination to put me at ease...

Using a non-adjustable new timing chain, "straight up" install puts the cam 4 degrees advanced (108, card call for 112 degrees install). With Felpro gasket, the SCR / DCR is 9.03 / 7.32 - i.e. too low, as far as I understand.

If I install a shim head gasket (.020 thick), the SCR / DCR jumps to 9.45 / 7.65. I.e. better for DCR but maybe not great for detonation given iron head / heavy car / 3.07:1 rear ratio / poor combustion quench.

Question:

What do the experts suggestion for my application? "Do not over-complicate", invest in an adjustable timing chain + shim head gaskets, "buy an LS" (haha - no way!).


Cheers/Alex

 

Im not an expert by any means, but will speak from experience.
At the VERY least, replace the pistons with new ones, you can have custom pistons made that will give you near zero deck.
The advertised compression ratio is always lower than actual.

 

The Buick people that come thru shop here automatically cut deck surface on heads and block to bump compression.

 

-Adujustable timing chain set and a degree kit to properly install and degree your cam.
-Cut the block deck and head surface just enough to clean them up for mating purposes, plus you'll gain some compression and head cc's
-Recondition your rods and have ARP bolts installed, buy some Custom pistons (Autotec or Diamond) to help achieve 0 deck, they're not much more $$ than off the shelf pistons but you get better results.
-Have your Qjet properly rebuilt and tuned to your new soecs/combo, I used ken at Everyday performance but there's others on the board here too.
- And lastly it's a must in my book especially since you have a big car (I have a 69 Riv) is get one of JW'S 9.5" big car converters you'll have your mind blown on how different the car becomes and acts on the street, they're amazing and a hands down "must mod" for big cars.

There's 1000's of things you can do and spend $$$$ like crazy to achieve it but that's just a quick list to stay with your budget friendly engine spruce up and to not get too crazy.

 

(may be obvious)
Don't forget to check the push-rod length. Cutting block/heads/valve job and gasket thickness from OEM add up.

 

That .100" or more total clearance is what makes such a low comp motor detonation prone as your piston tops prove out.

I would do whatever I had to to get your total clearance to no more then .045".
The chambers are deep in those heads and decking the head is a great way to unshroud the valves from those deep chambers!

I would mill the head .035" and make up the rest with Pistons with more compression height.

 

Thanks all for the input so far - all sound and meaningful. However, this is a budget rebuild and by the time one put new Autotec / Diamond pistons, machine block, re-balance crank and so forth, it won't be a budget overhaul anymore... Pistons / cylinders measured fine according to servicing manual for a re-ring job and that is the route I am taking.

I am planning to put the engine together and keep it original (with exception of small cam) and have plans for a new 482 power plant through JW later in 2021 with all the goodies including new converter - henceforth, I am not spending on pistons and machining now... It is summer time in Australia and I want to start enjoying the car over the next 2-weeks or so.

The poor quench is something the car has lived with for over 50 years. I experienced detonation myself on a 40degC day driving of freeway conditions... Pulled some time off (vacuum hose) and was back to business. WOT blasts were not a problem when temperature has been under check, even at 34degrees total advance. The TA-212 will increase cylinder filling and likely make detonation worse - I understand that.

I have assembled the short block already and given above background, I would appreciate advice on the combination of the following two parameters:

1) Camshaft install: what would be an adequate camshaft install position (i.e. how many degrees retarded / advanced) and
2) Should I use shim gasket (0.02in) for higher SCR / improved DCR or use Felpro (0.041) for a lesser DCR, performance and detonation prone characteristics?

Cheers/Alex

 

Thanks Larry, that is exactly what I've been thinking too - I will go through the "thin gasket and 4 degrees advances" route and report to the board later on how did it end.

Cheers/Alex

 

I am on the final stages of installing and commissioning engine back, hope to get it started on this weekend.

I installed a B4B and though this would be a straight swap but carb sits higher and some 1-2 inches forward the original position - meaning a new detent transmission switch bracket and a few "bumps and adjustments" here and there. Question: will the hood close with original filter given carb sits higher and forward? It is a 67 Riviera.

Cheers/Alex

 

Hood to air cleaner clearance on these Rivs is very tight. Are you using the Star Wars air cleaner? I have a performer intake and Qjet on my 455 in my 69 Riv and I had to make a Custom drop base for my star wars air cleaner so it wouldn't rub on the hood, and thats with the hood insulation removed already. The base I made sits 1/4" lower than a stock SW base. If I remember correctly from what I've read the performer intake puts the carb close to a stock intake location whereas the b4b moves the carb up and forward. You may have clearance issues using that intake.

 

I bought the B4B because I read somewhere "it would be fine" (perhaps the same TA source before mentioned?).

The car is the original LHD - and I won't change it! It is a Californian model fitted with the AIR systems and standard air cleaner, which looks rather tall indeed. I removed (and stored...) the AIR system but not keen on replacing the original air filter for some "chromy" aftermarket. I guess I will have to put the hood back and see how if fits... Will report back with findings.

Cheers/Alex

 

News are, Riviera is back to business!

B4B + OEM air filter touches the hood's sound insulation - I used some crumbled aluminum foil and it gets compacted to ~1/4in but there is not problem to close it or the hood "bulging".

Did some ~15 min break in of cam, 60 PSI oil pressure at 2200rpm. Then went for a drive, have got 20-25 psi with 15W40 oil hot at some 600rpm idle, otherwise runs at 40-45 psi at ~1500rpm. I did some "street tune up" and idle did creep a bit after second and then third 10kms drive. Engine still feels a "bit tight", I suppose the cheap cast iron rings may take a few load cycles to know their place!

TA212 sounds great, is has a very slight lope. I was planning to leave the switch pitch on high stall constantly but there is no need, the car launches off idle without hesitation. Carb had the original tune and did not have to do any (jetting) adjustments so far. It is operating without choke but it literally takes some 30 sec of feathering the throttle to get it going.

Next steps:

- There is a small oil leak from new sensor line / branching fitting. I did not want do over-tight the brass fitting but looks like I under tighten it...
- Did change the trans dipstick o-ring on the past but never stop leaking. After engine removal wiggling, it is bad (worse) again... Anyone knows a better alternative design of tubing and PN? For now, will just put another o-ring and silicone...
- I will invest in a wideband to check carb with some science. Have got an "800 cfm APT model" tuned to Cliff's book, will install it after all the commissioning is completed.
- Drain water and "washed off 50-years barnacles" I could not wash and complete fill with coolant.
- Change oil/filter.

In all, happy days - I call it a success! Thanks all for the hints and tips.

Cheers/Alex