Any motorheads know about blown engines?

[Zoomschwortz]

I've been collecting parts for my 68 Fastback Mustang mid life crises car. So far I have a T-56 6 speed, Global West tubular suspension and EFI 5.0 with a Kenne Bell Blowzilla/Flowzilla Twin screw blower.

I have always liked the Airflow Research cylinder heads and notice that they are now making the AFR185 head in a 72cc chamber.

72cc would put the stock forged piston engine in the area of 8.12 compression and I'm thinking about running a Comp Cams XE274 cam.

This is my question

How much boost can I safely pump into my engine while running 92 octane gas?

Thanks
Ken

[Zoomschwortz]

I didn't get this edit posted in time.

Do you know of any online calculators that let you know if you have exceeded the limit of 92 octane fuel when you change compression ratio and pounds of boost?

Thanks again
Ken

[Rabidsquirrel]

What's the compression on the motor?

If it came with any sort of forced induction, just throw the blower on it. If it didn't, I'd keep it low. Sorry, not very useful, but it's a start.

[Zoomschwortz]

Originally Posted by Rabidsquirrel

What's the compression on the motor?

If it came with any sort of forced induction, just throw the blower on it. If it didn't, I'd keep it low. Sorry, not very useful, but it's a start.

Stock is 9.0 to 1
AFR 72cc chambers would drop it to 8.12 to 1

I saw dyno test with this blower, the XE274 cam and AFR185 heads and it made 508hp. The problem is, they don't say what octane fuel they used or what compression for that matter. Depending on the head they used at the time, I believe the compression would have been around 9.0 to 1 or just shy of 10.0 to 1

[GrumpyOleTroll]

http://www.performancetrends.com/download.htm#eapro


alot of free trial sims for engines.


I might have Desktop dyno around here...let me look.




Shawn

http://www.zealautowerks.com/index.html

For messing around, it tends to read high, I've used it many times. The are a very respected name for Hondas.

Well throwing a PSI # at you is not the best to help really. Being it'll depend what you are using as FI. You stated you want a blowzilla (2.1L roots blower) are you sure that's not going to be over kill?

Are you planning on doing rods pistons etc ?

Really with wedge motors they can't take as much comp or a psi (compared to same sized/speced inline) Just the nature of the beast. Not at all to say they are weak or bad.

For knowing when you pass what 92 is safe start looking at other builds what the get away with, tuning is key for sure. But there are also limits what the metals can take. Remember gas we get isn't always perfect so don't tune to the finest hair for .01 extra HP unless it's a bracket car.

I've built a ton of motors planned even more for people and tuned a bit. The only 5L I did was retrofitted to carb touch of boring, and a big lumpy cam.

A 5L plus a t-56 would be a joy stock with a good roots on it yum!

Please feel free to ask any questions or tell me I went over your head. I tend to do that lol.

funny you mention a 68 Mustang....

We just finished doing a transplant...TODAY...no kidding....a 302 stroked to 347 came OUT of her and into, well, another Ford "product"....

Keep your eyes open for an F150 that is NOT a truck


And the 68??

It's on life support right now....

[taltos]

Originally Posted by tobii3

funny you mention a 68 Mustang....

We just finished doing a transplant...TODAY...no kidding....a 302 stroked to 347 came OUT of her and into, well, another Ford "product"....

Keep your eyes open for an F150 that is NOT a truck


And the 68??

It's on life support right now....

Sounds like somebody is building a Lightning that will out perform a factory Lightning. Nice job.

[Zoomschwortz]

Originally Posted by Ace$nyper

http://www.zealautowerks.com/index.html

For messing around, it tends to read high, I've used it many times. The are a very respected name for Hondas.

Well throwing a PSI # at you is not the best to help really. Being it'll depend what you are using as FI. You stated you want a blowzilla (2.1L roots blower) are you sure that's not going to be over kill?

Are you planning on doing rods pistons etc ?

Really with wedge motors they can't take as much comp or a psi (compared to same sized/speced inline) Just the nature of the beast. Not at all to say they are weak or bad.

For knowing when you pass what 92 is safe start looking at other builds what the get away with, tuning is key for sure. But there are also limits what the metals can take. Remember gas we get isn't always perfect so don't tune to the finest hair for .01 extra HP unless it's a bracket car.

I've built a ton of motors planned even more for people and tuned a bit. The only 5L I did was retrofitted to carb touch of boring, and a big lumpy cam.

A 5L plus a t-56 would be a joy stock with a good roots on it yum!

Please feel free to ask any questions or tell me I went over your head. I tend to do that lol.

Thank you for the link.

I already have the blower and will most likely use an aftermarket EMU and 45 lb injectors.

I also have a low miles 1988 5.0 that comes from the factory with forged pistons. They tend to split this block in half when they get into the 800+ hp range, but seem to live a long and happy life in the 550 hp range.

I have Desktop Dyno and have had great luck using it for N/A engines. The problem I have is it doesn't have my Twinscrew blower and I haven't had anyluck getting the same results that books and magazines have posted, so I don't feel comfortable using it for this engine. Another thing that I really need to know is when I've gone over the 92 octane limit.

They did this build a few years ago, the problem is they don't say if he used the 58cc or 61cc heads and they don't tell what octane fuel he was running.

How well does the new Kenne Bell BLOWZILLA/FLOWZILLA work? Muscle Mustangs and Fast Fords Editor Richard Holdener recently tested the Kenne Bell BLOWZILLA/FLOWZILLA kit on his own engine with the Westech engine dyno. The little 302 had #185 AFR heads, Comp Cams #274 cam, 75mm throttle body, 77mm mass air, Kenne Bell Switch Chip and 42 lb injectors. The combination made an amazing 508HP at 9.2 psi and 484 at 7.5 psi with a pavement ripping flat torque curve (453-483 ft lbs). 483 ft lbs @ 4000 rpm. That's 500" engine torque numbers. The boost never varied or dropped off from 2500 up - and there was another 9 psi left in the supercharger.

My goal is to have an engine that makes 500-525 hp and around 500 tq.

With the price of gas likely to go up, I want to use as much ignition timing and compression as practical and still get this hp at full throttle.

As you know, the timing of the cam events can make a huge difference in effective compression, fuel requirements and fuel economy.

The higher my static compression, the better my fuel economy when I'm not on the gas. Since I want to drive this car, I want to get around 20 mpg on the freeway and with the 6 speed I should only be turning 1400-1500 rpm at 70 mph.

Everything hinges on telling when I have gone over the 92 octane limit. I also have the option of using water injection that will let me increase the boost by 2 or 3 lbs as well.

Thanks
Ken

First post on the asylum but I would have a chat with the lightning guys as they use the bells in that CC motor all the time.

My last boosted project was a 65 cobra with a chevy 350 a 142 blower. Compression was around 9.2 and running about 9 psi with the street pulley. Better equivlent heads and a much more aggresive cam though.

Fuel is going to be your main concern as well as boost bleed off on the street. Cooling in a mustang with that motor and clearance on the top is going to be a issue as well, a extended cowl and a dual fan setup with some careful coolant choices (with a larger radiator) is going to be a must. I had major trouble getting everything to fit in my 67 K code and ended up hack then bar up a good bit out of the front of the car.

Originally Posted by taltos

Sounds like somebody is building a Lightning that will out perform a factory Lightning. Nice job.

Funny thing is, the original engine barfed out the crank and the timing chain at around 1130 AM yesterday.....just shy of midnight we finished the heart transplant, cranked it over, and immediately went deaf.....

[Zoomschwortz]

Originally Posted by tobii3

funny you mention a 68 Mustang....

We just finished doing a transplant...TODAY...no kidding....a 302 stroked to 347 came OUT of her and into, well, another Ford "product"....

Keep your eyes open for an F150 that is NOT a truck


And the 68??

It's on life support right now....

I had a ride in a Lightning a couple years ago and was really impressed with how well it hooked up.

Are you using the blower on the 347?

I have kicked around doing a 331ci, but after last years gas prices and after seeing the power they are getting out of the 4.6 litre engines and still getting good gas milage, I think I'm gonna stay with the 302ci or maybe check into going down to 289ci.

Thanks
Ken

[Zoomschwortz]

Originally Posted by wearymicrobe

First post on the asylum but I would have a chat with the lightning guys as they use the bells in that CC motor all the time.

My last boosted project was a 65 cobra with a chevy 350 a 142 blower. Compression was around 9.2 and running about 9 psi with the street pulley. Better equivlent heads and a much more aggresive cam though.

Fuel is going to be your main concern as well as boost bleed off on the street. Cooling in a mustang with that motor and clearance on the top is going to be a issue as well, a extended cowl and a dual fan setup with some careful coolant choices (with a larger radiator) is going to be a must. I had major trouble getting everything to fit in my 67 K code and ended up hack then bar up a good bit out of the front of the car.

Welcome to the Asylum, I feel honored that you would make your first post on my thread. Thanks!

You make some good points.

I have been concerned about cooling and am considering the purchase of 67 or 68 GT350 glass kit with the vented hood so I can get more air into the radiator and also let more heat out of the engine compartment. I may even need to cut the firewall so the heat can go out the cowl, but that will be a last resort.

I'm not sure on what radiator I'll be using, but know it will need to be big enough for a big block and a good high volume electric fan is also a must.
I modified a Flex Lite Black Magic to fit on a Toyota pickup (big time overkill) and love how much faster the engine warms up in the morning and have never seen the temp gauge climb over half way while fully load with camp gear, pulling a boat, with the a/c on and climbing mountain roads in 80 degree heat. I love it.

What fuel were you using?

What heads were you using and were they iron or aluminum?

By "boost bleed off" are you talking about the bleed off from late intake valve timing?

Thanks again.
Ken