1G vs. 2G head for a street car

[2fastTSi]

Okay, for starters I'm trying to reassemble a 97 GST I got through a trade a while back. I have no intentions of taking this car to the track, it's strictly a street car.

What I'm wondering though, is there any benefit from swapping the stock 2G head for a 1G? I'm shooting more for torque then peak HP here, and I have a 2.3L stroker shortblock ready. The 2G head would be better right? Smaller runners, higher velocity? Maybe a set of 264/272's? I don't want anything crazy, just something fun that won't break the bank.

Just looking for some opinions before I put a top end together.

 

[jrohner]

2g heads work great. I'd say you might as well just go with 272's instead of 264/272; even 272's are probably kinda small for a stroker. My BC272's didn't hurt me anywhere, they actually seemed to help everywhere and spool rpm is identical to stock cams on my car. My 2.0 has almost too much torque; I'd seriously need slicks for daily driving if I had any more -- I'm sideways when the boost hits in 2nd gear. I wish I could get as much hp as I have torque, or maybe a little less torque since that is what's hard on drivetrain parts. I don't know how these transmissions can hold together on a stroker; even a 2.0 has a lot of torque until you get over 500hp out of them.

What turbo are you looking to run?

edit:
How do you get traction with a stroker and FWD for a daily driver? My 2.0 AWD has smoked the tires quite a few times.

I ran in FWD mode for a little while cause of a tranny issue, and I could smoke the tires hard core even passing people on the highway, and that's when I had 340fwhp/380torque with stock cams and SMIC! I had to turn my boost down to 17 to have traction in 3rd.

 

[2fastTSi]

I haven't gotten to run the stroker yet. I'm looking forward to it though.

For now, I'm gonna stick to using the 14B off of my other car. I know a 9.5:1 stroker is probably way overkill for such a small turbo, but I think I'm gonna be running a little short on funds after the longblock build.

Thanks for the info.

 

[mysticj]

9.5CR + 14b + 2.3L + 2G head = Early/Quicker Boost

 

[DSM_PWR]

I have a 2.3L stroker shortblock ready...... Maybe a set of 264/272's?

Those are waaaaay too small for a 2.3 stroker... 280s are perfect for strokers

I would go with a 1g head...

If not your going to have so much low end power that ppl with top end are gunna pass you right up

 

[dsm-onster]

Where is all the proof that a 2g head/intake spools a turbo faster? None of that, "My boyfriends buddy did a swap and found out." It makes sense that it does. But since there has never been concrete proof, and no one has reported a loss in spool speed doing a 1g head swap, thought there are 10s of thousands done over the years, there's reason to believe that the 1g head doesn't lose low end for topend as many claim.

A super budget turbo that will function like a 16g (airflow per psi and +18psi power) is a 14b with a used 7cm^2 turbine housing swapped to it. The 14b compressor wheel flows 34lb/min. With the 7cm^2 housing swapped to it, you will have a 16g compressor cover, 16g turbine wheel and 16g turbine housing. You will have a faster spooling 34lb/min compressor wheel while the the small an big 16g have 38lb/min and 39lb/min flow potential respectively. 34lb/min is enough for 300whp. The 16g can push 300whp on pumpgas. You should be able to do the same with the 14b with the larger turbine housing, since you will be flowing about the same amount of air per psi as the 16g.

Fp3 cams are stroker designed cams. Fp3 cams are fp2X cams with a slightly difference amount of overlap. Fp2x cams have about the same duration at 272s. Straight 272s with adjustable cam gears will give you a GREAT set of cams for a stroker. Or go for fp3 cams.

 

[BoredDSM]

Where do you want your power band at? 9.5:1's are WAAAAAY overkill for a street car especially a stroker running a 14b. You would have to run e85 on a very safe tune just to not get an outrageous amount of knock. People go 8's on 8.8:1's. 2g heads have smaller ports and you are correct with them having higher velocity. 1g heads are said to be stronger because you do not have to have the head stead holes in the head bored out to 12mm and they also come with larger ports which is better for forced induction.

 

[2fastTSi]

Thanks for the info everybody.

I have a set of FP2x's on my Talon, they seem a little much for the 2.0L. I may use those on this engine instead. I was hoping a wiseman was gonna jump in on this

As far as the knock goes, that's really the only thing I've been concerned with. E85 is not an option, the nearest E85 station to me is in Bristol, TN and that's an hour drive. A little much just to get gas

So what does everybody think would be a safe tune? 9psi?

 

[BoredDSM]

Thanks for the info everybody.

I have a set of FP2x's on my Talon, they seem a little much for the 2.0L. I may use those on this engine instead. I was hoping a wiseman was gonna jump in on this

As far as the knock goes, that's really the only thing I've been concerned with. E85 is not an option, the nearest E85 station to me is in Bristol, TN and that's an hour drive. A little much just to get gas

So what does everybody think would be a safe tune? 9psi?

Why in gods name would u wanna run 9.5:1 compression ratios? Just run 8.5:1. It would be ridiculous to run 9.5:1's on the street when you can just get 8.5:1 and be easier to tune.

 

[Dsmj89]

Get the higher flowing 1g head, your car will spool fast as it is with a 14b and 8.5 compression, why spool faster ? As mentioned above your car will fall on its face real fast.

 

[dsm-onster]

Thanks for the info everybody.

I have a set of FP2x's on my Talon, they seem a little much for the 2.0L. I may use those on this engine instead. I was hoping a wiseman was gonna jump in on this

As far as the knock goes, that's really the only thing I've been concerned with. E85 is not an option, the nearest E85 station to me is in Bristol, TN and that's an hour drive. A little much just to get gas

So what does everybody think would be a safe tune? 9psi?

I didn't look at your profile . Get an intake cam gear and advance the intake cam about 3 crank degrees. Wala! fp3 cams. Tested by fp to work very well with a 100mm stroke.

BTW there is absolutely nothing wrong with 9.5:1 pistons. Porsche and ford have been boosting their warrantied cars for years before direct injection with more compression. You will need a computer control system that will retard your timing to MBT for higher compression. An safc won't cut it.

 

[2fastTSi]

Looks like I've opened up a can of worms with this motor...

Why in gods name would u wanna run 9.5:1 compression ratios? Just run 8.5:1. It would be ridiculous to run 9.5:1's on the street when you can just get 8.5:1 and be easier to tune.

Well, the shortblock is all ready together so the 9.5:1 is a done deal. I had no intention of running ridiculous amounts of boost or a monster turbo with this engine (and still don't). I just wanted something fun to ride around on the street in.

By all means correct me if I am wrong, but we are looking at effective compression here correct?

((Boost / 14.7) + 1) x static compression = effective compression

So 20psi on a motor with 8.5:1 compression gives you an effective compression of 20:1. Running 16psi on a motor with 9.5:1 works out to 19.84:1. Staying below 20:1 on pump gas is what I've been told is recommended, so I figured I would be fine. Am I wrong?

 

[dsm-onster]

You can run more boost if you alter your timing curve accordingly. . . Higher compression simply increases the burn rate. Start the flame too early and you detonate. With higher compression you ahve to start the flame later to avoid detonation AND to make BETTER power. A strong timing tune is about timing the fire right; it's not about timing advance.

 

[BoredDSM]

I didn't look at your profile . Get an intake cam gear and advance the intake cam about 3 crank degrees. Wala! fp3 cams. Tested by fp to work very well with a 100mm stroke.

BTW there is absolutely nothing wrong with 9.5:1 pistons. Porsche and ford have been boosting their warrantied cars for years before direct injection with more compression. You will need a computer control system that will retard your timing to MBT for higher compression. An safc won't cut it.

Were they boosting those cars back in the day of 103 octane being pump gas?

 

[dsm-onster]

Those were 80s and 90s cars. Barring the jetfire and corvaire, turbos were not popular enough to be mass produced for use in the US until the 80s. No 103 octane leaded fuel in the 80s at the local pump.

Octane partially determines burn rate. Retard the timing if you have high compression. Since like lowering octane, raising comrpession speeds up burn rate. You won't lose power by retarding timing because MBT will be at a later time. And you'll get the benefit of better thermal efficiency of high compression.

High compression has a bad rap with boost because builders seam insistant that more timing equals more power. However, RIGHT timing equals more power.