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We made a 3`Stainless straight ultra quiet exhaust and WOW, what a difference...

24 psi on stock manifolds, holy geeze. I think the car can only handle so much before it pops.
He's not reading it right. The graph is ancient...he would freak out reading the new one.

The Map KPA reading is in absolute pressure. You have to remove the atmosphere, here at low altitude, remove 100 KPA...
So we are running 64 KPA of boost (8 psi) on the stock 3.8 pulley.

Now my MAP sensor is maxed out at 200KPA (14.5 psi of boost) but I'm running more. Around 18 psi of boost currently with the 2.6 pulley.
I peak at 37 Lbs/min which means I'm over 350HP probably closer to 370HP (at the crank)
 


Wow boost stacking much?
Boost stacking ? lol
it's called having less V.E.
High lift Cams, ported heads, headers and gen V would reduce the need for such high boost to produce the same power.
But the way I did it is so much less work and less money.
 
and its also slower and less reliable.
I'll be going in the 12s are real street tires, close to mid 12s on E.T. street tires. That is on one engine.
I have 2 to build. My goal is most bang for the buck. This is supposed to be an economic racer.
If I start putting 3 and 4K of parts and a week of labor to install it all, that's not my goal.
I want both engines, fairly low maintenance, cheap to replace if one where to fail. Same for the transmission.

I will definately go for headers on both front and rear engines which will help some. I don't think I will go for cams...
I want these engine to sound as close to stock as possible. No loping, no extreme loud dump out the side.
My goal is to have a low 10 sec total sleeper and maybe go in the 9s without a large budget.
This is an fun experiment, nothing else.

So far I have 3K total including the car and I'm going in the 12s you can bet on it.
Of course I'm not counting our shop labor as it would then rack up a bill of 5K total.
 


I just read all 6 pages, and I am baffled and impressed at the same time. Making the assumption that you infact are NOT trolling most of everyone on the board and this is all completely legit, I am jelly. I want the exhaust, no lie. Prefer to go a different route for power, it works for you, but I DD my car so I need reliabilty over sheer power at the potential cost for re-fueling and chance to blow **** up.

But regardless, subbed for more WTH moments and a truthful :th_thumbsup-wink: Good Job.
 
How exactly is two engines a reliable and cheap budget build?
Engines can be bought low miles for under a 1 grand tested from recycling centers.
Transmissions for 600$ tested as well.

We have pick it yourself yards we can get the engines + tranny on special for 300$ together but untested.

Anyhow the whole rear engine set up can be purchased for under 2K including the sub frame including a used aluminum radiator.
The time to do the swap is where the money is but we do it at the shop.

Two engines and two transmission are more reliable. According to my calculations two stock engines would run low 12s and be very reliable.
Because it would be the equivalent of having one L67 in an AWD 2000lbs car. Less stress on the transmission.
If I can run 12s with one engine two engines of the the same power level will get me deep 10s@ 125-128mph if I can get the front the hook up.

At this point my reliability ain't bad and I can replace the engines/trans for cheap.

It is not a "cheap build" but if I can run 10s for under 7K total, AWD and stock engine/stock trans with a car that is as quiet as a stocker if not more. That will be cool.
 


I just read all 6 pages, and I am baffled and impressed at the same time. Making the assumption that you infact are NOT trolling most of everyone on the board and this is all completely legit, I am jelly. I want the exhaust, no lie. Prefer to go a different route for power, it works for you, but I DD my car so I need reliabilty over sheer power at the potential cost for re-fueling and chance to blow **** up.

But regardless, subbed for more WTH moments and a truthful :th_thumbsup-wink: Good Job.

Thanks !

I am definately not trolling. All the info I provide is true. Anyone who wants to see timeslips or other proofs just ask.
 
Two engines and two transmission are more reliable. According to my calculations two stock engines would run low 12s and be very reliable.
Because it would be the equivalent of having one L67 in an AWD 2000lbs car. Less stress on the transmission.
If I can run 12s with one engine two engines of the the same power level will get me deep 10s@ 125-128mph if I can get the front the hook up.

If you are running deep into the 12s on 1 motor, I think its still a bit of a stretch to say you would go deep 10s with a second. I say this because that is claiming a full 2 secs on a AWD change. Now granted, you should be able to pull off the line like a rocket, but I would say at best you go from a 2.0 60' to a 1.5 60' which would at most save a full second off the 1/4 time and that is to say you don't shell one of the trannies in the process.

I get the calculation that the AWD power/weight ratio will be much different, but you are also talking about the motors being different power figures, unless I missed something. You would have to have both motors built identical, making the same power, and the trans geared the exact same and able to handle the power/torque of the motors or once you get moving the 2 drivetrains will be fighting each other and that will slow you down. Could be cool, front makes 300whp and pull the car, back motor makes 500whp and smokes the tires the whole way... but you'd still only go as fast as the slowest motor could pull the car, or you'd break something along the way.
Same reason why front and rear differentials have to be the same on a 4x4, the transfer case would shell due to them turning at different speeds with different force. Everything has to work together.

Just my 2 pennies.

Still hoping for a Snowflake TVS WTH that is awesome, congrats result once this is all done. (long story)
 
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If you are running deep into the 12s on 1 motor, I think its still a bit of a stretch to say you would go deep 12s with a second. I say this because that is claiming a full 2 secs on a AWD change. Now granted, you should be able to pull off the line like a rocket, but I would say at best you go from a 2.0 60' to a 1.5 60' which would at most save a full second off the 1/4 time and that is to say you don't shell one of the trannies in the process.

I get the calculation that the AWD power/weight ratio will be much different, but you are also talking about the motors being different power figures, unless I missed something. You would have to have both motors built identical, making the same power, and the trans geared the exact same and able to handle the power/torque of the motors or once you get moving the 2 drivetrains will be fighting each other and that will slow you down. Could be cool, front makes 300whp and pull the car, back motor makes 500whp and smokes the tires the whole way... but you'd still only go as fast as the slowest motor could pull the car, or you'd break something along the way.
Same reason why front and rear differentials have to be the same on a 4x4, the transfer case would shell due to them turning at different speeds with different force. Everything has to work together.

Just my 2 pennies.

Still hoping for a Snowflake TVS WTH that is awesome, congrats result once this is all done. (long story)

Any time you talk about two engines and two transmission there are a few guys that think it cannot work unless both set ups are 100% synchronized.
This a flawed logic.

Both engines are fully independent and only help each other. You may be thinking about rowers in a boat...
motors are different. They have the advantages of running gears and both having capabilities to reach the same speed.

But ideally if they both shift at the same time, have the same gear ratio and tire size, it would cause less issues.
One issue that can arise with two engines is when one is shifting the other is pushing it above it's normal speed which messes the TCM up.
That's why I'll try and avoid this by having them both shift at the same time, although it would probably work even if they had different ratios.

Also for ease of driving, if both engine have the same powerband it's easier to handle as it would act like a 4wd, not like two independant 2WD added together.

This has been done before and it works. I had the idea about the project in 1998 but I didn't have the means to complete a project like this back then.
 
BTW I did a test today. Since I'm injecting nearly 25% methanol into my total fuel mix through methanol injection. I figured even with my stock injectors I still had enough fuel left that I could run E85 mixed with 91 at a 80/20 mix.
So my total alcohol mix would be over 85%.

Now I did the math and adjusted injector rate accordingly and I ended being way to rich on my tune. Which means the E-85 probably does not have 85% mix of alcohol, more like 70% (winter blend)

Results, KR, 3-5 all the time but a perfectly stable A/F of 11.1

So I may be on to busting a myth that says you can't mix leaded fuel with alcohol since my AV Gas LL in combinaison of 80/20% Meth/H20 mix does not knock at all.
Just like my C16 didn't knock when methanol was activated but had a lot of KR when I disabled it.

So Lead works well with Alcohol when it is injected seperately. I know leaded fuel tank rusted badly when alcohol was introduced. Maybe there is a relation. The lead does not react well with the moisture in the alcohol making it less effective.
Lead's excellent thermal conductivity is at the highest when it isn't corroded. Maybe I'm on to something but I'll keep testing.
Luckily my motor looks to be still in good shape, but I'm taking risk at the power level it is making. But the engine is worth less than the typical 1 liter engine we work with on the sleds which are worth 5K.

I'm still extremely dissapointed with how easy it is to get knock with a 3.8L iron head engine, no wonder many get hurt when guys who don't scan mod them.
 


I ran exactly the time I thought I would since the changes.

Last time I ran 13.3 @ 103mph with the 2.8 pulley
Now with the 2.6 pulley, better tuning done by Turbo Dynamics (myself) higher shift point of 6400rpm !!
ran 12.9 @ 107mph !! Still on winter tires and on a slow track. Any other track further away are .2 and 2 mph quicker !
This is one fast GTP.

I ran the 12.97 @ 107 with an exhaust dump. 13.01 @ 106.7 mph with the full exhaust. It can run 12.9 with the exhaust I just didn't run it at the right time when the track was sticker.
Made over 20 runs all 13.0 @ 106mph...very constant car. I just lack traction. With good R compound it is a 12.5 car with slicks it is a low 12s for sure. I don't get in the throttle hard until about 50mph.

So here are the mods done to achieve 12.9 @ 107mph.
Exhaust
2.6 pulley
HP tuners tuned by myself
water/meth injection precisely tuned.
Cold air intake
300 lbs weight reduction

That's it...

Bone Stock engine
Bone stock trans
Stock axles
winter tires on heavy 18" rims (46lbs per wheel)

I have over 120 runs total.
My airflow shows 40 lbs per min peak, I must be close to 390HP at the crank.

Now I'll stop messing around. E.T. Street tires are going on and maybe a nitrous kit and I will run it in between gears (not during shifts).
hoping for high 11s but realistically it has to run very low 12s.

videos and timeslip coming up.

btw the exhaust loses .5mph only because of the 44lbs weight reduction. Power is identical with the exhaust dump vs full exhaust.
 
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I would highly recomend you take a look on 3800pro. Under turbocharged400sbc username youll find the twin engine build he did a while back and get sone ideas before you commence this build
 
wicked passes man. i hope to perfect my launches and dish out wicked times.

i have a pet peeve when it comes to drag strips.

people spinning street tires in the wet box.... it is useless and does nothing but make your tires less productive. the hotter street tires are the slicker they are. they are the complete opposite of drag slicks.

not only are you messing up your street tires but, your heating up your engine before you even launch.


very annoying to me. i know your thinking, who am i to talk, i cant even launch my car. I am just annoyed by noob things like that.


PS- your still one of my idols when it comes to GPs
 
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