Hey guys
i have been offered a high comp motor to buy, and although i want a VLT engine, this seems a realy good deal, and wats been done has been done really good.
Ide just like to know wat peoples thoughts are on high comp motors. i went for a drive in one last night with stock boost(7psi) and the thing was awsum...
is 2g's for engine, turbo ecu, loom, custom dump and intercooler a good deal? as far as im aware the engine was just built up..
thanks
Carl
I dont think thats a great price for a n/a converted motor unless, it has been rebuilt and stuff?... the price isnt too bad but is he negotiable.. You could probably get a genuine turbo motor minus the turbo for around $1200-$1600.
you will always get more power from low comp + high boost, than from high comp and low boost. also think about how long the motor will handle high comp + boost....
i have a highcomp in my calais bein going great for about 6 months now.. you will find allot of people bad mouth highcomp engines frced 6 is a good bloke to talk to pm him
LOL i ended up in a big fight with ^^^ about them. No hard feelings of course
I dont like it, i wouldnt do it and wouldn't encourage it. They will make good power on low boost, but for every 3psi of boost you can almost add 1 point of compression. So basically, its like having 5psi before you start. Then add the 8-10psi your gonna run and you got the equivelant of 13-15psi, if not more, into 300k km old standarad cast pistons.
Not to mention gearbox and diff that will slosh around for a while.
You see where this is headed?
Some original photos have not been recovered yet.
Quote:
Originally Posted by Epitaph
LOL i ended up in a big fight with ^^^ about them. No hard feelings of course
I dont like it, i wouldnt do it and wouldn't encourage it. They will make good power on low boost, but for every 3psi of boost you can almost add 1 point of compression. So basically, its like having 5psi before you start. Then add the 8-10psi your gonna run and you got the equivelant of 13-15psi, if not more, into 300k km old standarad cast pistons.
Not to mention gearbox and diff that will slosh around for a while.
You see where this is headed?
Thru the traffic lights or down the 1/4 faster than a stock VLT?
Some original photos have not been recovered yet.
sorry to hijack the thread, but with the decomp plates, whats the best to get? as i hear the copper head gaskets arent really good and 3layer steel gaskets are the way to go.
Quote:
Originally Posted by Epitaph
yes, but for a certain early death.
Who has stock VLT's these days anyway?
Smart people who dont want to rebuild their pieces of **** VL's every 2nd week?
can someone please answer my question im getting all my turbo gear fitted next week (hopefully if workshops dont **** me around again) just wanna get peoples opinions on the gasket to use for lowering comp.
Some original photos have not been recovered yet.
Quote:
Originally Posted by AFG-WPN
can someone please answer my question im getting all my turbo gear fitted next week (hopefully if workshops dont **** me around again) just wanna get peoples opinions on the gasket to use for lowering comp.
Ive never really had any1 say anything good about a decompression plate. If your gonna be getting a motor built spend the extra and get the lower comp pistons. Stocko ones go for what 200 on here? Get some new rings for the *******s and your set.
Some original photos have not been recovered yet.
Quote:
Originally Posted by Raptor
Then balancing also? lol price goes up man..
Decomp plate lets you run a little more boost, make sure you have enough fuel!
If you can afford to have a motor built then you can afford to have them balanced and all the rest. If not your in the wrong game, with building high powered cars. If I was you I would just run high compression and just keep winding boost into it. If it blows up it blows up buy another bottom end or complete motor. I dont see why you would want to cut corners if your gonna spend the money on building a tough motor tho
ahhhh here we go, found a good little read in an older thread
this is direct quote from what kyle (6boost) had to say
"Ok, the only RELIABLE way to decompress the thing is to use the Cometic head gasket as Matt suggested. It is 3mm thick, read- .120" thick. This would be the same as running 3 head gaskets together, or 1 head gasket and a 2mm decompression plate. On top of eliminating all of these things, the Cometic head gasket is one of the best qaulity gaskets available, they are a 3 layer metal head gasket, same thing as HKS etc, we have one in a GTR making 500rwhp on pump fuel, runs 26 psi all day everyday, standard head bolts and no O rings.
Forget all this bullsh1t about compression ratio. Peopl are all going on about stuff that is purely speculation. Tell me, what do you think has higher effective compression ratio, 7.8:1 compression with 26psi, or 8.5:1 with 20 psi?? I'll tell you, the one with more boost. People just don't understand that there are heaps of cars out there running 25+psi on turbo bottom ends, so why don't you think a NA bottom end could handle 15psi stock, and 20psi decomressed?? It will be fine."
looks like ill be getting the cometic 3 layer head gasket
Some original photos have not been recovered yet.
high comp motors are great to drive, no lag etc. had one when i first converted to turbo. but you cant really wind the boost up when your used to the power.
plus i ended up cracking the bottom end of mine, hence resulting in getting it built up again.
so yeah id now prefer to do it once instead of twice.
thats just my opinion but i still havent heard of anyone with a good story to tell about them
thanx for the response guys.
im stil unsure of wat to do, its a really good deal and has just been built up. it was a very good NA and has just been converted, has turbo injectors which have been cleaned etc
i dont want to rush things, hence me asking all of u for opinions. but i culd be going from boring NA to turbo in 2 days.. its just too exciting heh
im told its strong..
Carlos
Man just like Epitaph said above. Not the best way to go about it but not every one can afford a low comp setup.
2Grand is abit rich anyway. On the other hand i have seen plenty of High Comp Engines boogey and seen some **** themselfs. What are you planning on doing with your auto?
Guys i have 175rwkw on 10psi High comp motor.
VLT oil pump, cam, plenum, computer, injectors, etc.
Been like that for about 3 years at least, NO problems at all !
I give it a hard time, driven daily.
No lag, heaps more torque.
As said, you can't run as much boost but like any motor, you need it tuned right.
When people blow a low comp motor they say; oh it was worn/old or it was tuned bad/leening out etc.
When a high comp motor goes they say; must have been the high compresion
You need a good cooler for a high comp motor and fuel system to match.
Fact is, Holden had such low comp because there was no cooler on the stock VLT. 9:1 is probably too high but 7.8:1 is too low for a street car IMO
Low comp=Good for drags/ all out power
High comp= You'll be at the next lights by the time low comp hits boost!
You need good average power through the rev range, not just above 3000rpm.
Some original photos have not been recovered yet.
