Compression Help

[the big JC]

im trying to work out how i could lower the compression in my L24E to make it more suitable for a turbo so what i want to know is if anyone knows if there are decompression plates advalible for the L24 and where to get them or would it work if i used 2 head gaskets if im going to do the turbo conversion i want to be able to run a decent amout of boost safely and i was told by a mate thats in the engine re-con buisness that i wouldn't be able to run any more than about 4psi boost but some one on here told me up to 15psi so i think the best option will be to lower the compression and run a intercooler to help prevent (KABOOM!!!) lol

the reason the L24ET project is back on is because ive recently found someone who will insure me but i still wont be starting it for about 12 months as i have to finish my 1200 project first

[blind_elk]

It's only 8.5 now. That's plenty low enough for a turbo. (same as a RB20DET).

The problem you may encounter is that the whole combustion chamber was never designed to be running in a forced induction environment. So it may be difficult to get the tune right.

If you really must decompress it, try a 260 or 280 head, because they have bigger combustion chambers. They probably have better port designs as well.

[the big JC]

It's only 8.5 now. That's plenty low enough for a turbo. (same as a RB20DET).

The problem you may encounter is that the whole combustion chamber was never designed to be running in a forced induction environment. So it may be difficult to get the tune right.

If you really must decompress it, try a 260 or 280 head, because they have bigger combustion chambers. They probably have better port designs as well.

so you recon that it could handle higher than 4psi boost it would just be difficult to get the air fuel mix right could a jay car digital fuel controller help to get it right

[blind_elk]

Well, RB20s handle 10 - 12 psi fairly comfortably at the same C/R. As I said, the main drawback could be the chamber design (this is the advice that has deterred me from the same course; and I've got a perfectly good L20ET sitting in the garage, and a Wolf 3D that used to run it also doing nothing. They get installed next week).

Any sort of aftermarket ECU has to have a chance of letting you run higher boost levels.

[the big JC]

Well, RB20s handle 10 - 12 psi fairly comfortably at the same C/R. As I said, the main drawback could be the chamber design (this is the advice that has deterred me from the same course; and I've got a perfectly good L20ET sitting in the garage, and a Wolf 3D that used to run it also doing nothing. They get installed next week).

Any sort of aftermarket ECU has to have a chance of letting you run higher boost levels.

I know its not going to be easy but i like a chalenge and the fact that there are only a handfull of people who have done it makes it more attractive ive always wanted my car to stand out from the crowd so if its doable then i will do it (one day)

[66yostagea]

Get on to Ghostrider. He's the GURU of 30land.

[the big JC]

yea i know ive already found out heaps from him

[Ghostrider]

yea i know ive already found out heaps from him

When your ready to do this, lets do it right, I have the manifolds and the knowledge now for what you need, but in the mean time find yourself a P90 head and Flat Top Pistons.

You will still be working with about 8.5:1 with a much better head. The P90 was the 280ZXT head.

Your also going to need a 65mm TB from either RB25DE or KA24E from an U12 Pintara T or Ti, or Corsair Ghia.

The manifolds are identical to those on L20ET's, the inlet might have slightly smaller plenum, than the L28ET but it's only marginal, it's the length of the runners that makes all the difference.

The L20ET ECU would make everything a lot easier, but your going to need a loom as well as the plugs are entirely different. Probably a Microteech Piggy Back to control the fuel and boost will do the trick.

Someone else that will help you is BenDR30, as he is in Adelaide and has a 240Z Turbo.

I am doing a 2818 L28ET at the moment to drop into my PNV, and from that I expect about 300+ HP at the wheels. If that don't make you stand out from the crowd nothing will.

Let me know when your ready and serious.

Cheers,

Dennis

[the big JC]

when i recently found out that i could get insurance i started geting ready to do it again but then i brought a datsun 1200 so most of my money goes into that at the moment and on top of that i just blew up my motocross racing bike the other weekend so thats a mess and is gonna be a bitch to fix im also re-building my little bros Honda Z50 so ive got alot on at the moment so i was planing on just starting colecting parts and then maybe by a piece of shit R30 to try it all on incase something goes wrong cos i can't afford to go with out my car but im 100% serious about it i had all the money organised but then my insurace told me they wouldn't insure me and that no one else would so i had to scrap it.

So i have to use the P90 head or can i keep the stock one cos i can't have my car off the road for too long and it would be alot of stuffing around id have to get all the valves re seated and get the head faced and shit im realy looking for a fairly basic setup that can run decent boost safely prob nothing over 10psi i rather just get started off with a basic setup and then get a head and pistons and stuff to start making some serious power later down the track.

What stuff do you have and what do you want for it so i can keep it in mind when ive got some spare cash any thing i can get off you would be a big help all the stuff i need is pretty scaerse around here when i was chasing all the stuff last time i found a guy that had everything i needed but he was in NZ.

also do you have that fuel gauge for me

Cheers josh

[Ghostrider]

when i recently found out that i could get insurance i started geting ready to do it again but then i brought a datsun 1200 so most of my money goes into that at the moment and on top of that i just blew up my motocross racing bike the other weekend so thats a mess and is gonna be a bitch to fix im also re-building my little bros Honda Z50 so ive got alot on at the moment so i was planing on just starting colecting parts and then maybe by a piece of shit R30 to try it all on incase something goes wrong cos i can't afford to go with out my car but im 100% serious about it i had all the money organised but then my insurace told me they wouldn't insure me and that no one else would so i had to scrap it.

So i have to use the P90 head or can i keep the stock one cos i can't have my car off the road for too long and it would be alot of stuffing around id have to get all the valves re seated and get the head faced and shit im realy looking for a fairly basic setup that can run decent boost safely prob nothing over 10psi i rather just get started off with a basic setup and then get a head and pistons and stuff to start making some serious power later down the track.

What stuff do you have and what do you want for it so i can keep it in mind when ive got some spare cash any thing i can get off you would be a big help all the stuff i need is pretty scaerse around here when i was chasing all the stuff last time i found a guy that had everything i needed but he was in NZ.

also do you have that fuel gauge for me

Cheers josh

Josh,

I don't particularly want to part with any of it, as I have been collecting it for quite some time now. But if I have to at the time and you can't get it anywhere else I might be tempted, but wait till you can't get it somewhere else.

You want a fairly basic setup then.

OK! You need to get the inlet & exhaust manifolds from an L20ET, get a throttle body from any 280ZX, or 280C maybe, would have to check differences in size if any. A compressor from the FJ20DET will work wonders and I just happen to have one for sale in good condition, I paid about $300 for it so I'm open to any reasonable offer. And some fuel & boost control, maybe a piggy back Microtech as I spoke of.

Probably set you back about a grand all up and you would have a package equal to or maybe better than a stock rex and at minimal cost. At under 10psi it should ber fairly quick and somewhat reliable.

You wont need a shitter to try it on as everything is bolt on except for the wiring of the piggy back ECU.

BUT! if you want real go, you want an P90 head & flat top pistons and lots of heat coatings and performance, real performance cost $$$$$'s, unfortunately.

Yes I have the gauges and i will pack em up on Friday when I'm off next.

Cheers,

Dennis