forcefed3.8's
Buckeye Bullet
- Joined
- May 26, 2002
The .85 housing is a waste unless you are in the 9s. The ta33 is a ta49 in a hot air housing. The t31 turbine works best with the .63 Garrett housing. No gain going larger.
Spinning motor to 6k rpm
- Thread starter Wahoo
- Start date
- Joined
- May 28, 2001
How about you clearing things up..........
Well here is my plans.
I'm already on E85 so we will start there with the fuel.
E85
Either stock turbo crank with billet mains but pistons yeilding more compression maybe around 9.5:1.
Or if funds allow forged stock stroke rotating assembly, maybe long rod stroker kit if it truly is worth what I believe might put more side load on piston skirts( I'm not a professional so I'm probably wrong) which I would imagine to be more load on the block when I could just raise boost? Again I'm not a professional so I'm probably wrong.
Probably stock heads because the funds for this year would only get me bottom end and roller cam - at least a good base to build on for the next year.
If I have more money than I anticipate, I'll get ported irons and maybe a bigger turbo.
I already have a th400 and a 3k husek converter, so might need to at least add some c clip eliminators for the 10bolt.
I'm already on E85 so we will start there with the fuel.
E85
Either stock turbo crank with billet mains but pistons yeilding more compression maybe around 9.5:1.
Or if funds allow forged stock stroke rotating assembly, maybe long rod stroker kit if it truly is worth what I believe might put more side load on piston skirts( I'm not a professional so I'm probably wrong) which I would imagine to be more load on the block when I could just raise boost? Again I'm not a professional so I'm probably wrong.
Probably stock heads because the funds for this year would only get me bottom end and roller cam - at least a good base to build on for the next year.
If I have more money than I anticipate, I'll get ported irons and maybe a bigger turbo.
I already have a th400 and a 3k husek converter, so might need to at least add some c clip eliminators for the 10bolt.
Pronto
Believe nothing you hear and half of what you see.
- Joined
- Dec 9, 2002
IMHO, if you don't have the funds to build it once don't do it until you have the funds. You're not going to want to pull heads after the engine is built and running. Ported heads will open up your power levels. Stock heads should be cleaned, etc anyway.
Jerryl
Tall Unvaccinated Chinese Guy
- Joined
- Dec 14, 2004
OP, for your reference . . . when I was stuck with NA thinking . . .
The full weight HA with stock exh manifolds, 19psi 93/alky, 103F track temp, TA33, port matched irons/zero bowl or valve cleanup, stock valves, ported intake, 235 radials, 212 Flat tappet cam, comp 980's, stock rockers, PATs 2650 0/0 LU, ran 87mph in the 1/8, 107 in the 1/4, shifting around 5500. Best 60' = 1.98
Good luck.
The full weight HA with stock exh manifolds, 19psi 93/alky, 103F track temp, TA33, port matched irons/zero bowl or valve cleanup, stock valves, ported intake, 235 radials, 212 Flat tappet cam, comp 980's, stock rockers, PATs 2650 0/0 LU, ran 87mph in the 1/8, 107 in the 1/4, shifting around 5500. Best 60' = 1.98
Good luck.
My current engine is hurt, and I want to run it reliable next year so the build has to happen, hopefully the money will be there for the extras.
I bought an 86/7 intake, just need a few things throttle body, tps sensor, iac.
I have a welder, I'll rotate the tstat inlet if it's in the way of the hot air alternator or accessory bracket.
I'll fabricate/modify my own passenger header to move the turbo up front, if it's the cheaper route then buying 86/7 stuff. I'll weld a oil return bung in my oil pan.
I'm not gonna run AC.
I'm gonna try to fab up a front mount intercooler setup on a budget.
That's my plans, not going to be hot air.
SCOOBY DOO
BASED CANADIAN PATRIOT!!
- Joined
- Feb 18, 2007
Spin mine to 5500 on the 1-2 shift and 5800 on the 2-3 shift. Stock bottom end...and I bracket/grudge race the car every weekend spring to fall...and I've been doing it for years.
When I originally made the thread I assumed all the faster guys were spinning the engine a little higher, especially if they changed out the cam.
I just assumed if I build the engine for higher rpm it would have to be built very strong which, basically what I learned from all this is I want to build it for strength and reliability.
I just assumed if I build the engine for higher rpm it would have to be built very strong which, basically what I learned from all this is I want to build it for strength and reliability.
20psiofevil
Active Member
- Joined
- Feb 10, 2013
Also waiting to hear from bison on this subject...
Luckily my ford turbo 03 v6 has a butt load or parameters I can datalog and uses a high dollar maf sensor to calculate airflow. Once desired boost is reached in 1st gear the airflow #/min and maf counts flatlines and stays the same through all the gears and rpm ranges. What this tells me that when the rpm increases the engine is utilizing that airflow more efficiently because it is pumping faster. Turbine ar selection is based on rpm range. On 260ci through a 62cea turbine the pte .63 was done around 5400rpm. You could probably get 5600-5800 on a 3.8l though.
Luckily my ford turbo 03 v6 has a butt load or parameters I can datalog and uses a high dollar maf sensor to calculate airflow. Once desired boost is reached in 1st gear the airflow #/min and maf counts flatlines and stays the same through all the gears and rpm ranges. What this tells me that when the rpm increases the engine is utilizing that airflow more efficiently because it is pumping faster. Turbine ar selection is based on rpm range. On 260ci through a 62cea turbine the pte .63 was done around 5400rpm. You could probably get 5600-5800 on a 3.8l though.
Your info looks spot on. Seems these turbos are strong when exhaust pressure to manifold pressure ratio is 1.2-1.3:1. The 62 on my engine was still making power at 1.4:1 but manifold pressure was falling off and ex pressure was increasing. It was all in and done at 5700. With manifold pressure in the low 20's using an extra wastegate on the crossover I was able to keep it 1.15-1.2:1 and it pulled to 6200 on the Dyno. Still showed higher peak with the higher manifold pressures even though exhaust pressure was rising fast which is why it's so important to have the proper gearing and converter. It was brutal between 5000 and 5500 but dying beyond 5600 when it's turned up. -8 overlap at .050" and 8.3:1 CR. Its likely -12 overlap @ .050" and 9:1 CR would have picked up power when working it. There's a very distinct turbine requirement vs mass flow. The P trim t04 76 is super strong from 55-65lbs/min and will go to about 75lbs/min even on a junk engine. The 62 high flow is about as good. The stage 5 which is also 62mm exducer flows a lot and is exceptional at high shaft speeds so it works well with smaller compressors. The high flow 66 turbine is a monster for its size. It works really well from 65-85lbs/min air flow. The larger compressor covers are required to get the flow out of the 66 wheel. We've seen huge gains in power with just a slight increase in compressor while using the larger compressor covers even even using the same 66 turbine and t4 ex housing. Literally ran away over 5500rpm with almost 100whp gain at 6000rpm. We concluded the big gain was the fact that exhaust pressure likely dropped tremendously. We were using a super aggressive hyd roller with a little too much overlap for most of the 3 bolt applications but it sure liked the big compressor cover and slightly larger turbine.
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