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Blowthrough build repeat.

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I kept forgetting to hit record on the logger so I only have logs from the 2nd hit and the 10.88 passes.
From the data I got I can keep on turning up the boost and leave even harder, the ignition timing is still under 20* .
Going to have to get a new boost gauge I'm over it's range.
 
Seems like I may be taking the top end off for a reseal soon. So believe I may have lifted the odd bank head after the last track outing. Once off the trailer I put the Buick in garage and it sat for a week with the slicks on. Got it out for a cruise last Friday and the car would cut out if you got into boost, figure the fuel filter is clogged or my tune went wonky after the last data log. I put it up and the next day pulled it back out but it was missing a bit and then cleared up but I could smell coolant. I checked the radiator and it was half full, topped it off and checked the oil, damn milkshake but the level was low.
I fired it back up let it get up to temp with the milkshake oil and it ran fine, didn't miss and the coolant level in the radiator is the same.
I'm going to try a re-torque on the head studs and change oil and see if the coolant stays in the radiator.
RJC head gaskets with studs, I've never had one leak or blow out before.
 
Yeah, I'm well aware of what water does in oil and I'll take the chances with the HP series king bearings holding up to the idling time with the mixed oil. I'll have decided what route to take now by the weekend.
 
I had an RJC seep before under boost between #5 and the coolant passage at the back. That was on a stock short block with factory heads that had been ported and surfaced. I bought a large 1/2" thick piece of glass on line somewhere and used some 3m spray adhesive, and adhered some 220 wet sand paper to it. The piece of glass was sized to put 3 pieces side by side in the short direction. The floating process for making glass makes it about the flattest thing you can buy. With the block on the stand I started sanding the deck. You could immediately see the high and low spots which were numerous, and it was low between #5 and the coolant passage. It took a while to sand each side flat. I also checked the heads on the glass by sanding a little, heads were flat. After cleaning everything up, I reassembled with cometics. I followed what some other guys on the board did, I think it was Jerryl who recommended the method. I took the cometics apart, washed them, and sprayed hylomar on each layer both sides, and assembled. No leaks of any kind. After my current build, I did the same with the cometics, but the block was surfaced at the engine shop, no leaks this time either.
 
This current block deck was surfaced for gaskets like Cometics when I got it, it's flat and I did the heads myself the way you mentioned a few years ago.
I'm going to pull the top end check the RJC gaskets out and reseal it if they check out.
 
Saturday night tear down and I see the culprit. #1 blew sealant out into the valley, the rest looks like when I put it together.
Bad light pic:
I'm working on removing the head to see the condition of the RJC gasket and the block/head decks.
 
A retorque definitely wouldn't have worked. The decks are good as well as the gasket, the block deck had some heat buildup right at the fire ring. So going to clean everything up and reseal the RJC gasket on the odd bank. Will be back up ready for track action this week given the valve cover gaskets/boost gauge arrive on time.
Block with the heat mark:
Head with RJC gasket still attached:
 
Delay but moving on,
Head is back on and torqued, I'll recheck it in the morning.
Going to use my new tall TA turbo 6 valve covers this time. This setup goes back together quickly but I'll have to pause for a grommet on the intake to catch can, the old one was split and filling my lower intake base with oil. Also will have to revise my catch can/breather setup, I just gained two more breathers on these valve covers.
 
It may be the picture but that one cylinder looks a lot leaner than the others? What do the plugs say?
 
It may be the picture but that one cylinder looks a lot leaner than the others? What do the plugs say?
It's steam cleaned from the gasket leak, That's #1 cyl. All the plugs are black and look like they should be thrown away but I'm going to run them.
 
Torque check this morning was good, I went over ARP/RJC specs to 90 ftlbs.
I retorqued the even bank head down that I didn't remove this time, two ARP nuts under the valve cover took almost a half turn to get to 90 ftlbs.
Time to button this all up tonight and finish, I have to plug/delete breather port on even bank valve cover after mock up. No clearance for a breather and the charge pipe into the carb hat.
 
Took a few trips and run time but coolant seeping into #1 after several heat cycles. It was worth a shot to reuse the warped gasket but failed.
Pulled both heads this time and will install new RJC gaskets as soon as I get them.
 
Well not quite what I expected to see upon disassemly, gasket layed down great actually but the GE sealer didn't exactly stick everywhere and was uncured gooey in places. I grabbed all the GE silicone sealer tubes I had from the kits, new unopened tube 03/19 expiration. The tube I used had no expiration printed on it. So I now believe sealer just failed because of age and that was the source of the coolant seep. The new gaskets/GE sealer still in mail as of this post.
I still fully intend to finish this and attend the last few track events that are left this season.
 
Cracked or a pinhole in cyl 1 so this finished my year off on this machine.
On to another 109 build.
 
I think I said this before, but your test mule experiments and posts over the years have been some of the best reading and info. Keep up the good work.
 
I think I said this before, but your test mule experiments and posts over the years have been some of the best reading and info. Keep up the good work.
Thanks Sir, I will keep up on it, I have learned a lot over the last 15 years and enjoyed all of it's high and lows. I also like sharing it with my Buick brothers!
 
I have a lot of good parts to keep on with a 109 3.8L and that is the plan.
But..
When I want to change it I have a very nice engine build I have been collecting parts and info for.
Just post it here.
Fully forged 10:1cr 4.1L for future power using:
T6P stock stroke steel crank
Molnar 6"rods
Racetec pistons
Will still be iron headed though.
 
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