• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

mod+boost ?????


well when it comes to supers i cant really help you not my area of choice. underdriving will hurt a super engine. all i can say is good luck, and godspeed.
 
underdriving will hurt a super engine.

i dont think theres a supercharger on the market that doesnt have a rather large selection of different diameter pulleys available for it. getting your boost back with the addition of an underdrive crank pulley would be as simple as going down the next size supercharger pulley. and you still get the benifits of underdriving your other belt driven accessories.
 
You were right about a cam with a lot of overlap, but porting and larger valves are a very good thing to do with a turbo engine.

I agree. It was(still is?) a common misconception that super- and turbocharged engines did not benefit from increasing the induction and exhaust flow. Truth is that they benefit even more than normally aspirated engines. Even raising the compression makes turbo engines more efficient as long as octane isn't a limitation.
 
actually raising the compression makes it to where you cant run as much boost due to gasket failure and overpressuring breaking rods and carnage. you can boost a high compression engine just not as much as a turbo engine and everything has to be carefully monitored so knocking from spark/fuel doesnt happen. you put 20 psi on an 11:1 engine your gonna have problems, but 6-8 can be used safely w/ proper tuning.
 
actually raising the compression makes it to where you cant run as much boost due to gasket failure and overpressuring breaking rods and carnage. you can boost a high compression engine just not as much as a turbo engine and everything has to be carefully monitored so knocking from spark/fuel doesnt happen. you put 20 psi on an 11:1 engine your gonna have problems, but 6-8 can be used safely w/ proper tuning.

Out to lunch again dude.

There is way to many factors that determine if an engine is going to detonate than compression and boost.

Its all give and take, if you have an efficient chamber, you can run more Boost, Timing, and compression than a less efficient chamber. If your limited by your chamber, you can adjust timing, to get more boost, or vice versa, lots of little things. Head material also makes a difference.

My Folvo is probably going to be in the 10:1 neighborhood and it will eventually get 30 psi, but its is an aluminum head with highflow ports that has something like an 11:1 ratio stock on the volvo and runs on 87.
 
I guess my last line "as long as octane isn't a limitation" was easy to miss. If octane isn't a limitation, then knock isn't going to be an issue.

A good example of high octane and good chamber design working together can be found in the import drag racing arena. I remember a Honda from close to 15 years ago that was running 11:1 and 30psi. At the time it was the most powerful drag Honda around with something like 700bhp. And no, wandering samurai, that was not on a stock engine with any worries of bending rods or blowing gaskets.
 
Last edited:
i fig as much but i guarantee you wont be driving it daily w/ that setup. ive seen it b4 too, hart racing had it and runs one similar to that now. the highest compression/most powerful engine ive seen was an 8.5:1 skyline running twin turbos at 1550hp/890ft lb tq on 124 cam2 fuel. it had 46# boost on the engine. the largest high compression engine boosted ive seen was a 6.0 corvette running 22psi on 11:1 again on 124 cam2 fuel. it cranked 1200hp/970 ft lbs tq. the timing was almost really retarded (just a few degrees) and the chambers were hogged the hell out. i realize that it can be done, but for practicalities sake and daily driving or street/strip use your not going to go above 93 octane and about 8 psi on a high compression engine, and no more than about 20 on a lower compression engine.
 
... i realize that it can be done, but for practicalities sake and daily driving or street/strip use your not going to go above 93 octane and about 8 psi on a high compression engine, and no more than about 20 on a lower compression engine.

Once again dude, how can you make a blanket statement like that?

You dont know what you can run unless you know every aspect of a particular engine, and even then you can adjust things to make it work.
 
underdrive pulley don't help because you usually can't get a small enough pulley on the supercharger to make up the lose, and small pulley on the blower will also increase the chance of belt slip.

thomas Knight. first off have you ever scene a photo of one on a ranger? for years he was know as a hack. sending out kits claiming to fit and being 1 inch above the hood line.
 
im not saying it cant be done just saying that for a regular joe just looking for a few ponies and a longer lasting setup wont push the limit. just like me im only going for 300hp thats 15 psi in the engine im looking to build, thatll be plenty for street/strip use and daily driving if i so choose. if i wanted to push the limit and put it on the strip or extreme offroading alone id push the internals to borderline breaking point and shoot for 30psi and whatever hp figure i could imagine, prob around 450/500. thats not my intention however, so im going w/ the comfortable figure, and im pretty sure thats what the guy on here that initially asked would the upgrades work w/ boost was wanting. yes mild engine tuning and relieving of the ports w/ a proper cam will work for a few extra ponies (200+). gutting the internals and tweaking everything to the limit and cranking the boost w/ higher octane fuel/methanol etc is necessary for extreme hp (325+).
 
actually raising the compression makes it to where you cant run as much boost due to gasket failure and overpressuring breaking rods and carnage. you can boost a high compression engine just not as much as a turbo engine and everything has to be carefully monitored so knocking from spark/fuel doesnt happen. you put 20 psi on an 11:1 engine your gonna have problems, but 6-8 can be used safely w/ proper tuning.



With a decent fuel and tune, you can do some insane compression and boost. GM Racing's 2.35 liter ecotecs found in drift cars are 14:1 compression and 20lbs boost. That's on e85 that you can get at the gas station.

Granted, these are purpose built motors, but my ranger on e85 had no problem with 30 lbs at 8.5:1 c.r.

A lot more can be done than you are saying can be done.
 

Sponsored Ad


Sponsored Ad

TRS Events

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Ranger Adventure Video

TRS Merchandise

Follow TRS On Instagram

TRS Sponsors


Sponsored Ad


Sponsored Ad


Amazon Deals

Sponsored Ad

Back
Top