What kinda boost can I pull off premium?

WiseAssJester · 09-24-2005, 03:49 PM

Thanks a lot homeslice.

I have a work provided vehicle for going to work and back.. and groceries and what not. Its a lot easier to say "I'm sorry" then ask for permission.

So the car is only gonna run about 50k miles before I pull it apart and freshen it.

That and I always baby my babies.

So about when do I have to hit up 104 race gas?

rnoswal · 09-24-2005, 06:39 PM

I think that at about 10 to 1 compression you are pushing the 93 octane pretty good. My Celica had 14 to one compression and had to use 110 octane. It would be nice if there was a chart that listed what compression you get with different boosts. There is probably a formula to figure it out. There are other sites that have monster outputs from the 7m engine, maybe some of them would have a formula for what you are looking for.

Russ

WiseAssJester · 09-25-2005, 01:14 AM

14 to 1 off of a Celica? I didn't realize they made dome pistons that big.. or a head chamber that small. Damn.

And 12:1 compression will push a muscle car(350) on 93 octane, altitude dependant.

Actually, I'm pushing about 10:1 right now, maybe a bit higher, off of my other car and haven't had much detination. Actually, because of the incredibly oversized camshaft, I had to bump up the timing a touch. Err.... more then double stock.. Heh. SHould be between 4 and 8 degrees stock. I'm running at 15.

rnoswal · 09-25-2005, 06:03 AM

Well I had a set of Wiseco domed pistons that had 25 cc domes. The head was milled so that the chambers were around 65 cc's. Giving a couple of cc's for the head gasket. I had close to 42 cc chambers. That put the compression right at 14 to one. I also had the timing set to 35 degrees total advance at 4000 rpm. I usually ran it to 7500 rpms before letting off. I had dual Dellorto carbs and that was a fun dirt track car to run. I wish I had the carb set for the Supra, 3 side draft carbs!!! Oh yeah. I had to sell the Celica though, they dropped the class at the end of last year. I sure do miss it.

Russ

intense 7MGTE · 09-26-2005, 05:59 PM

In order to run 30psi of boost you will need a bigger turbo first of all. The stock CT26 can only push out 15psi and at that point it is just blowing hot air. Secondly you will need a stronge top and bottom end wjich you have. Then you will need a tuning computer like a VPC2, a SAFC or better yet a EMS from AEM. Then you will need to run at least 100 octane to keep the motor from blowing sky high. 91-93 pump gas just will not cut it.

WiseAssJester · 09-27-2005, 12:21 AM

At what altitude? Tempuratures?

I appreciate the input, but lack only forced induction experience. I've built other beasts a'fore.

Thanks matey.

20 or 25 considered safe?

Isphius · 03-16-2006, 09:14 PM

and what is the best way to lower compression? wouldnt a thicker gasket be weaker? the only thing i can think of is shorter pistons and/or con rods, but where can you get those?

Isphius · 04-08-2006, 03:49 AM

Has anyone ever but a delorto or webber carb set up on a supra? youd only need 255 cfms for 6k rpms and at 80 % volumetric effciency. Maybe more or less. Youd just have to make your own manifold for it. I would only do that if i had an expensive fuel injection problem thou, like a fried coil or ecu. And you would also need a vaccum advance distributor or some kind of controler for the electric one

09-26-2005, 05:59 PM	#5
intense 7MGTE Stock Join Date: Jul 2005 Posts: 20	30psi and octane In order to run 30psi of boost you will need a bigger turbo first of all. The stock CT26 can only push out 15psi and at that point it is just blowing hot air. Secondly you will need a stronge top and bottom end wjich you have. Then you will need a tuning computer like a VPC2, a SAFC or better yet a EMS from AEM. Then you will need to run at least 100 octane to keep the motor from blowing sky high. 91-93 pump gas just will not cut it.

03-16-2006, 09:14 PM	#7
Isphius 500whp yet? Join Date: Nov 2005 Location: Long branch, NJ Posts: 1,006	and what is the best way to lower compression? wouldnt a thicker gasket be weaker? the only thing i can think of is shorter pistons and/or con rods, but where can you get those? __________________ Yay the supra assistant is gone!!! WEEE!!

04-08-2006, 03:49 AM	#8
Isphius 500whp yet? Join Date: Nov 2005 Location: Long branch, NJ Posts: 1,006	Has anyone ever but a delorto or webber carb set up on a supra? youd only need 255 cfms for 6k rpms and at 80 % volumetric effciency. Maybe more or less. Youd just have to make your own manifold for it. I would only do that if i had an expensive fuel injection problem thou, like a fried coil or ecu. And you would also need a vaccum advance distributor or some kind of controler for the electric one __________________ Yay the supra assistant is gone!!! WEEE!!

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09-24-2005, 03:49 PM	#1
WiseAssJester 3" Exhaust Join Date: Sep 2005 Location: Reno Posts: 77	Thanks a lot homeslice. I have a work provided vehicle for going to work and back.. and groceries and what not. Its a lot easier to say "I'm sorry" then ask for permission. So the car is only gonna run about 50k miles before I pull it apart and freshen it. That and I always baby my babies. So about when do I have to hit up 104 race gas?

09-24-2005, 06:39 PM	#2
rnoswal Lexus & 550's Join Date: Apr 2005 Location: Bossier City LA Posts: 556	I think that at about 10 to 1 compression you are pushing the 93 octane pretty good. My Celica had 14 to one compression and had to use 110 octane. It would be nice if there was a chart that listed what compression you get with different boosts. There is probably a formula to figure it out. There are other sites that have monster outputs from the 7m engine, maybe some of them would have a formula for what you are looking for. Russ

09-25-2005, 01:14 AM	#3
WiseAssJester 3" Exhaust Join Date: Sep 2005 Location: Reno Posts: 77	14 to 1 off of a Celica? I didn't realize they made dome pistons that big.. or a head chamber that small. Damn. And 12:1 compression will push a muscle car(350) on 93 octane, altitude dependant. Actually, I'm pushing about 10:1 right now, maybe a bit higher, off of my other car and haven't had much detination. Actually, because of the incredibly oversized camshaft, I had to bump up the timing a touch. Err.... more then double stock.. Heh. SHould be between 4 and 8 degrees stock. I'm running at 15.

09-25-2005, 06:03 AM	#4
rnoswal Lexus & 550's Join Date: Apr 2005 Location: Bossier City LA Posts: 556	Well I had a set of Wiseco domed pistons that had 25 cc domes. The head was milled so that the chambers were around 65 cc's. Giving a couple of cc's for the head gasket. I had close to 42 cc chambers. That put the compression right at 14 to one. I also had the timing set to 35 degrees total advance at 4000 rpm. I usually ran it to 7500 rpms before letting off. I had dual Dellorto carbs and that was a fun dirt track car to run. I wish I had the carb set for the Supra, 3 side draft carbs!!! Oh yeah. I had to sell the Celica though, they dropped the class at the end of last year. I sure do miss it. Russ

09-27-2005, 12:21 AM	#6
WiseAssJester 3" Exhaust Join Date: Sep 2005 Location: Reno Posts: 77	At what altitude? Tempuratures? I appreciate the input, but lack only forced induction experience. I've built other beasts a'fore. Thanks matey. 20 or 25 considered safe?