New engine build thoughts

-
I don't know how far you are into your build but have you considered o-ringing the block and adding even more compression?
Altitude eats up compression and alcohol will take more compression them 12.5.
My buddy is running 15.8:1 compression in his stroked chivy with a flying toilet.

More compression and a good starter!
He has eaten up a couple of AKA High Torque GM started in the Past 3 years.
 
Cudafever said:
I don't know how far you are into your build but have you considered o-ringing the block and adding even more compression?
Altitude eats up compression and alcohol will take more compression them 12.5.
My buddy is running 15.8:1 compression in his stroked chivy with a flying toilet.

More compression and a good starter!
He has eaten up a couple of AKA High Torque GM started in the Past 3 years.
Click to expand...


The difference in power between 12:1 and 15:1 is maybe, maybe 40 HP. Maybe. From 13:1 it’s even less. All it does is make the tuning window smaller and taxes the ignition.

All my testing of ignitions and alcohol showed a 4.5 amp Mallory Super Mag III was better than every battery fired ignition I tried. The only thing that got close was an MSD 10, but it, like the rest of the battery fired ignitions lost power as RPM went up.

An MSD 6 box was down almost 100 HP at 8500. It was down 65 or something like that at 7000. The 7 was in between the two. What was interesting was the weaker the ignition, the quicker power fell off.
 
gumper said:
I’ve raced at Spokane many time. I first raced there in 1998 when it was still AHRA. Last time I was there was for the Division 6 finals in 2015?

I have a Coan 8” spragless, 4800 stall. 1.5 rockers for now. 1.6 would be nice, but probably not happening this year. I use an AEM wideband for tuning, so AFR is always good. Timing has been set at 35*. Our corrected altitude is always about 7000’ at home which is a battle. Also use an old nitrous plate as a primer for starting on gas. At the end of each day I bring the engine temp too 200*, pull the breathers and let the moisture evaporate. Spray the intake with WD40 then crank it over before parking the car after the weekend. Never water in the oil.
Click to expand...
Have you ever thought of using that nitrous plate for what it was really intended for?.. again considering your lack of oxygen..
 
j par said:
Again for the lack of oxygen maybe even a turbo setup?..
Click to expand...
I used to use it. The 408 was initially built for a 250 shot. The street car thing around here died, so I went back to bracket racing. If heads up racing wasn’t dead around here I’d have a twin turbo setup through EFI. Probably not on an LA engine.
 
gumper said:
I used to use it. The 408 was initially built for a 250 shot. The street car thing around here died, so I went back to bracket racing. If heads up racing wasn’t dead around here I’d have a twin turbo setup through EFI. Probably not on an LA engine.
Click to expand...


Did you run alcohol over alcohol? I was going to use some nitrous, but the consensus at the time was run the engine on gas and use alcohol with the nitrous. At that time, I didn’t want to use gas so I just skipped it. Eventually I went back to gasoline and was much happier.

If I had to do it again, I’d skip the injection and use 2 carbs on gas.
 
yellow rose said:
The difference in power between 12:1 and 15:1 is maybe, maybe 40 HP. Maybe. From 13:1 it’s even less. All it does is make the tuning window smaller and taxes the ignition.

All my testing of ignitions and alcohol showed a 4.5 amp Mallory Super Mag III was better than every battery fired ignition I tried. The only thing that got close was an MSD 10, but it, like the rest of the battery fired ignitions lost power as RPM went up.

An MSD 6 box was down almost 100 HP at 8500. It was down 65 or something like that at 7000. The 7 was in between the two. What was interesting was the weaker the ignition, the quicker power fell off.
Click to expand...

Like me , not many twist their street engines to 7000/8500 -------------the old hemi would hit 7500 faster than I could keep up w/ back in the day , but didnt go any faster than at at 6500 . Wasnt any point twisting it tighter .
 
gumper said:
I used to use it. The 408 was initially built for a 250 shot. The street car thing around here died, so I went back to bracket racing. If heads up racing wasn’t dead around here I’d have a twin turbo setup through EFI. Probably not on an LA engine.
Click to expand...
Although my engine is not set up from nitrous I am going to try a small shot just for learning purposes mostly and watch this moments with my friends. I did figure when I was going to bracket race if I get back into it I certainly wouldn't be using the nitrous as I feel it would make inconsistencies??..
 
yellow rose said:
Did you run alcohol over alcohol? I was going to use some nitrous, but the consensus at the time was run the engine on gas and use alcohol with the nitrous. At that time, I didn’t want to use gas so I just skipped it. Eventually I went back to gasoline and was much happier.

If I had to do it again, I’d skip the injection and use 2 carbs on gas.
Click to expand...
I used gas back then. I only switched to alcohol 3 years ago for the consistency which I don’t regret. I don’t want to run fast enough to require a cage and the additional safety equipment. I also like to be in the middle of the pack so to speak when it comes to ET. Makes finish line racing easier.
 
gumper said:
I used gas back then. I only switched to alcohol 3 years ago for the consistency which I don’t regret. I don’t want to run fast enough to require a cage and the additional safety equipment. I also like to be in the middle of the pack so to speak when it comes to ET. Makes finish line racing easier.
Click to expand...


I understand.
 
yellow rose said:
Did you run alcohol over alcohol? I was going to use some nitrous, but the consensus at the time was run the engine on gas and use alcohol with the nitrous. At that time, I didn’t want to use gas so I just skipped it. Eventually I went back to gasoline and was much happier.

If I had to do it again, I’d skip the injection and use 2 carbs on gas.
Click to expand...
You wasn't going to use no nitrous...
Toke.gif

That's for people with cojones...:poke:..
 
gumper said:
I used gas back then. I only switched to alcohol 3 years ago for the consistency which I don’t regret. I don’t want to run fast enough to require a cage and the additional safety equipment. I also like to be in the middle of the pack so to speak when it comes to ET. Makes finish line racing easier.
Click to expand...
Just busting YR's seeds...
 
Any guesses on power numbers, and projected ET? Another chink in the armor was the old mopar cam was 4* advanced for low rpm street drivability.
 
gumper said:
Any guesses on power numbers, and projected ET? Another chink in the armor was the old mopar cam was 4* advanced for low rpm street drivability.
Click to expand...


That’s about where I put everything. My builds are aimed for 60 foot, then 330. The rest is easy.
 
gumper said:
I’ve raced at Spokane many time. I first raced there in 1998 when it was still AHRA. Last time I was there was for the Division 6 finals in 2015?

I have a Coan 8” spragless, 4800 stall. 1.5 rockers for now. 1.6 would be nice, but probably not happening this year. I use an AEM wideband for tuning, so AFR is always good. Timing has been set at 35*. Our corrected altitude is always about 7000’ at home which is a battle. Also use an old nitrous plate as a primer for starting on gas. At the end of each day I bring the engine temp too 200*, pull the breathers and let the moisture evaporate. Spray the intake with WD40 then crank it over before parking the car after the weekend. Never water in the oil.
Click to expand...

how much WD40 do you spray into intake? let the moisture evaporate first then spray the WD40 and crank it over?
 
79410aspenrt said:
how much WD40 do you spray into intake? let the moisture evaporate first then spray the WD40 and crank it over?
Click to expand...
After I get the engine hot I open the butterfly and squirt it in a few seconds. Then crank it over a few times to run it through the valves. I have sprayed it in while running too.

If it’s going to sit more than two weeks I drain the alcohol and fill it with gas, and run the car for a few minutes.
 
79410aspenrt said:
thanks. this methanol is new territory for me
Click to expand...


You will love it. Just remember rich pollutes the oil and heat is your friend. I used to tune with an O2 when I ran pump gas and did for awhile when I switched to alcohol but an egt tells you so much more. And you can get a stand alone system if need be.
 
79410aspenrt said:
thanks. this methanol is new territory for me
Click to expand...
I’d never go back to gas. Make sure you’re running the right heat range on your plugs. I had a little trouble with that in the beginning.

When warming the car up on race day I also bring it to 200* much like when shutting it down for the day. Oil temp is the most important part here. With the injection it’s simple to build heat when you want it. I keep the water temp about 160* all day during the races. Temperature control is never an issue when things are tuned right. On a hot day I may have to use the radiator fan.
 
Update on my engine project. No good news. Still haven’t gotten things back from the machine shop. Had to wait two months to get some .010 under bearings. Tried several places, and no one had any on the shelf. TTI tells me I have a two month wait time for a set of 1 7/8 headers every time I call including today.

Racing season is half over, and my car is sitting with an empty engine bay. Pretty steamed how this scamdemic has screwed up nearly everything there is to do.
 
Well another update today. The machine shop doesn’t even have my crank ground yet. Wouldn’t you tell people when you are behind work four months before they drop stuff off?
 
gumper said:
Well another update today. The machine shop doesn’t even have my crank ground yet. Wouldn’t you tell people when you are behind work four months before they drop stuff off?
Click to expand...


I can’t tell you how pissed off I would be. Takes me about a week to have a crank ground.
 
I dropped my block off at the machine shop on October...still not here.

To be fair I brought my head's in back in Feb. for new guides, 11/32 valves, a five angle redo and a skim cut on the heads.

Three months to get pistons didn't help and my shop owner closed up for some time because if the Kung Flu.
 
You must log in or register to reply here.
-

Back
Top