No power after rebuilding 18RG engine

[73GTV]

https://www.crower.com/media/pdf/regrinds.pdf

Here is a pdf that explains the different grinds via degrees/duration.

[OSS117]

https://www.crower.com/media/pdf/regrinds.pdf

Here is a pdf that explains the different grinds via degrees/duration.

Hey, very kind of you to provide the explanation sheet. Thank you.

[73GTV]

https://www.toymods.org.au/forums/th...-power-outputs

Old link but full of great information from other members of this forum back in 2007. Worth a review and should answer most of your questions without investing more than the time required to review these efforts.

[OSS117]

Thanks 73GTV!! Very helpful informations for me! Sergi

[OSS117]

Hi, as promised the dyno results:

engine power 114 hp
rear wheel power: 102 hp at 5400 rpm
torque: 160 nm at 4534 rpm

unfortunately i can not upload 19 KB file for the graph

[73GTV]

Hi, as promised the dyno results:

engine power 114 hp
rear wheel power: 102 hp at 5400 rpm
torque: 160 nm at 4534 rpm

unfortunately i can not upload 19 KB file for the graph

So this was with your current stock cams for this run correct?

This build was it with new pistons or just stock with new piston rings an refreshed cross-hatch hone?

I ask because you should be able to extract more power from that engine if these were over-sized pistons and rings.

The issues of blow-by from a worn block even with new piston rings which can't seal against worn area of that cylinder wall.

New clutch and flywheel?

Ok, I will stop with these questions!

[OSS117]

yes thats right, stock cams, just refreshed engine with new Piston rings, all gaskets a full tune up only. The header is a 421 hand made by a machine shop and a little wider with a Sebring muffler. New clutch and lighter flywheel only.

[73GTV]

After that upgrade, what was your compression on each of the four cylinders compared against the engine rebuild specs?

If you currently do not know, you should collect those reading and compare them against the factory compression specifications which will answer your original question asked at the beginning with your post.

Was the compression close to the spec?

Within the stated limits or below the minimum compression?

http://www.retrojdm.com/Files/18R-G_Cheat_Sheet.pdf

[OSS117]

Thank you for your repIy! I really do not know what compression was measured on each cylinder, because it is a swap engine and was not tested before. The guy who build he engine said will raise the compression ratio o 10.5.1 but I do not really know whether he really did and how to prove it. Or can I use the cyl compression as advised for that reading? I will check each cylinder the next days and post it.

I was never driving the car to max limit until rebuilding, I drove 2000km since then, but what I noticed is the last day, the top speed is only 160 km/h. thats slow in my opinion beside the specs I posted already. After the rebuild and with the handmade exhaust header I was expecting around 130 Hp, The muffler shop also said that the gain will be around 10% but its less then regular 122hp its only 115. Probably the cam timing is a little of or valves are not properly tuned.

[OSS117]

The datas on the cheat sheet does not match with the specs we have in europe probably. The strongest available 18RG had this specs I found:

Stock specs:
120 HP at 5600 rpm Myspecs: 114 HP at 5463 rpm

118 NM Torque at 4000 Myspecs: 160 NM Torque at 4534 rpm
Compression: 9, 7:1 Myspecs: 10,5:1 not tested
Topspeed 196,8 km/h Myspecs: 160 km/h
0-100: 10,6 sec Myspecs: not tested


So sth is wrong reaching top speed obviously.

[73GTV]

http://members.iinet.net.au/~stepho/...%20tune-up.pdf

The Green Book states: Set timing at 12 degrees BTDC. Page 2 and on page 29 please read the standard compression specification limits. Your compression is below that factory minimum compression reading for all four cylinders. Figure 3-98 item 4.

This green book is a download-able PDF which is the point I'm trying to explain to you, Slowly! This Green book is the Do It Yourself, the how to easy, to follow and understand. It list every tool you are required to personally perform these task.

The cheat sheet was from a good source but as you stated, different area may meet different emission standards.

Correction: I just re read your post from start to finish and you had indeed started looking at every possible issue.

I discovered from a good second read of your material. Keep it going, you are indeed on the right track to solving these issues with your engines performance. I hope that the source material presented answers most of your inquiries and I do not want the appearance of sounding like I know more about what is going on, when you are the person who is experiencing these issues.

I did not like how my answers came across after that review. I'm not in the military barking orders in hopes that I gave the correct advice to someone asking a serious question, and I'm only hearing my own static.....