Identify my engine/block

[~MoMo~]

Hi,

I recently got a gs-t spyder and upon inspecting the engine, the identity plate on the block only has SBR 500 stamped on it. It also appear to have what looks like 4g64 664 carved in there with a nail or something.
I´ve been searching but could not find any info on this engine? Is this a built slowboy block?

What is this engine? Compression is very high for a turbo, sitting right at 200psi. Everything looks like a 4g63T to me, oil feed/return, water cooling from the block etc etc.

Apperciate all help identifying this.

 

[bryanwheat]

It could be a slow boy engine. Being that it says 4g64 on the block it is likely a 2.4 or a 2.1 destroked engine. Other than that it is hard to tell what you have. You would have to pull the pan and inspect the bottom end to know for sure.

 

[rastmp]

How about a pic?

 

[GoCanes777]

^^^
+2
Picture please

 

[~MoMo~]

Ok, guess I have to pull the pan to verify then.
I'll try to get some pics up, anything particular or just misc engine bay pics?
I feel the compression is a little high though? The car came with a monster ebay/XS power t70-ish turbo and manifold, but that thing didn't spool until 5k+ so I went back to stock. Safc2 and 780cc's too, but again reverted back to stock.

Reason I'm bothering this much is because the enormous blue cloud the car makes whenever I hit boost. Absolutely no oil in intercoolerpipes nor any shaftplay in the T25. It even did this with the t70(?), so obviously the turbo is not to blame.
Compression numbers were 203-206-210-203, so pretty even but very high. PCV valve rattles when I shake it but I can't blow through it so I guess it's ok? Valve cover vented to atmosphere, as I have nowhere to connect it (intake is a little hacked due to previous owner/mechanic).
Could it be head lift or a bad headgasket not showing up on the compression test?
Any ideas?

 

[bryanwheat]

With compresson numbers that high i would almost assume that it is just a stock 2.4 bottom end or 9.0:1 or higher aftermarket pistons. Are you sure that it is burning oil and not just running real rich?

 

[~MoMo~]

Well the exhaust smells like burned oil and is blue in color whenever this occurs. Stock fuel; regulator-pump-injectors. Previous owner said it used a little oil, but he thought it was the turbo.

Spark plugs looks good, slightly white at the tip and very even colored. Looked like a clean, but maaaybe a little lean burn. So where the heck does this oil come from? I could even see a goldish color on the piston crowns when looking down the spark plug holes so no particular carbon buildup there.
The car runs great otherwise, doesn't overheat or anything. Small idle lope/surge from 1100-900 but nothing really obvious.
Could valve timing cause this compression? I lined up the cams and they looked good but I did not check the oil pump gear.

Also, I was thinking maybe the previous mechanic re-used the stock headbolts, as I understand they are one-time use only? Maybe they are stretched or atleast not able to clamp down the head properly due to the increased cylinder pressure caused by the high compression?

Probably time to pop the valve cover and have a look, is it adviseable to try to re-torque the bolts or should I just verify their tq and order new ones if they are not up to spec?
When I looked in the coolant reservoir 5 minutes ago I noticed that it was missing around 1 1/2 inch from the level I had topped it up to, but as I had to bleed the coolant yesterday it could be because of some additional air in the system. Either way I'll top it up and keep a close eye on it, if it continues to drop then it has to be head-to-block sealing issues?

 

[goodbye]

I'd say valve stem seals by the sounds of the blue cloud stuff, other than that, the rings.

Sounds like a built 2.4, stock 2.4 pistons don't fare too well in a turbo engine. If it is the rings, you might be able to just hone it out and throw in new rings, if the walls are bad, then you need machining and new pistons/rings.

 

[~MoMo~]

But why should the valve stem seals affect high load situations? I do not get any smoke on hard decel or prolonged idle. And if the rings are that bad shouldn't compression suffer? I ran wastegate boost tonight and there was little to no smoke, so it only happens at high cylinder pressure.

I'll be pulling the pan this weekend, maybe that'll clear things up as to what this engine actually is.

Thanks to all who have replied so far, much appreciated

 

[miguelmcv]

But why should the valve stem seals affect high load situations? I do not get any smoke on hard decel or prolonged idle.

I'll be pulling the pan this weekend, maybe that'll clear things up as to what this engine actually is.

Thanks to all who have replied so far, much appreciated

I don't think its valve stem which it would be worst when idle, I would go more towards the pistons rings.

And if the rings are that bad shouldn't compression suffer? I ran wastegate boost tonight and there was little to no smoke, so it only happens at high cylinder pressure.

I'll be pulling the pan this weekend, maybe that'll clear things up as to what this engine actually is.

Thanks to all who have replied so far, much appreciated

No, it will not affect compression, the Oil rings are for oil purpose only, with the compression rings are only for compression, You can have really good compression and have bad oil rings which it will cause you problem, On other hand, you can have bad or broken compression rings and still have good oil rings which it will affect compression, but will not barn any oil.

 

[jeber21]

no offense you just need a new car

 

[mattasi]

no offense, but you don't know what your talking about. It's just some blue smoke, it can be fixed. It's not totaled or something.

 

[brian9397gsx]

Very helpful. With blue smoke its oil being burned during combustion, so could be pcv could be turbo. Was there any oil in the intercooler pipes possibly left from the old turbo? I doubt it's valve stem seal or really piston rings as they ussually but not all the time smoke on decel. Theres so much positve pressure in the combustion chamber to really suck oil past the rings unlike under a high vacuum.

With out looking at the car id really lean towards oil in the intercooler pipes if none is found at least you ruled that out i guess.

 

[~MoMo~]

There is no oil in any intercooler pipes, not even oil residue. They are bone dry.
I can't replicate this under low boost condition (wg boost), this only occurs with stock t25 boost levels. I haven't lost any water since last observation either, so I'm a little stumped. Maybe the head is cracked ever so slightly.

Weird that the oil rings should make me burn oil only under high boost, but I guess anything is possible.
I'll try to change the pcv today, even though I think mine is working. It rattles and I can't blow through it (from intake manifold side).

 

[1davho]

I'm sure you have resolved this by now, but I bet its your turbo. Mine went out and would smoke under high boost, but no other time. I didn't even see the oil in the exhaust housing when I pulled it off, but it was covered in carbon anyway. A new turbo solved the problem.

 

[~MoMo~]

Just to update, I eventually pulled everything apart to replace a leaking head gasket. No effect on compression, but a leakdown told the real story.

The block is infact a built 4g64, eagle(?) h-beam rods, arp head studs, balance shaft removed etc. 100mm stroke, 87mm bore. 2G head.
Installed a new HG from Cometic, MLS @ .120 thickness to reduce static compression. Car runs very strong, but the T25 is in my opinion too small for this engine. Although the massive amount of torque in the lower rpms is fun, traction is a problem and it's hard to stay out of boost even when cruising.

-Bjorn-