Don Terrill’s Speed-Talk

I have no clue what is "the" max compression ratio. Depends a lot of engine design. I've ran about 17:1 compression ratio with small cams , and couldn't break it at wot.. on E85. Dynamic comp wasn't much less than 17:1 - bmw 2.8 liter 24 valve engine. Part throttle and lambda=1 caused exce...

E85 should reduce those emissions (CO, HC and NOX), if I remember correctly. Atleast CO and NOX. Catalytic converter (and how far it's located) has the most impact on emissions, if it's bad it'll require ridiculous amount of heat to reduce emissions enough to pass the test (depends on the car, tho. ...

I found the same thing (collector diameters)
Just got the new version of pipemax.

A lot different compared to 3.98.

Any thoughts?

I'll do some more testing later with more time on the new pipemax and see if I've just had inaccurate value(s).

Yes the cranks are very strong, but the blocks are known to crack at the water pump area. That is on the smaller bore engines that don't have the cylinder wall splitting problem. All the same it is interesting, to me, that when they went for 300hp/300ft-lb they upped the stroke from 90 to 93.someth...

Yes it is.
Also crank has quite large journals.

Thank you for the reply. I'll see what I can do.. just welding the floor doesn't seem that bad option. There is also the possibility to just fill the seat bore and have the seat and valve sit higher. Didn't even think about such as option earlier.. perhaps I should do some measuring and see if that'...

Hey, I'm currently working on a -530 Volvo 8 valve aluminum head (going to my own car for testing purposes). The ports require quite a lot work, exhaust port especially requires welding the floor (stupid shape). I have already welded the combustion chambers and done the 'raw cut' for them. What I ha...

Wouldn't the heavier crank be better, if thinking about harmonics ? 73lbs crank is quite near the crank I have in my Volvo B6304 engine. Journals are 50/65mm and weight 28kg (~62lbs), capacity being 2922cc. No problems revving more than 8000rpm, flywheel and damper bolts hold-on well, no issues. Tho...

Your work is simply just amazing.
I've read your whole thread, and it gave me a lot of motivation to just start fabricating stuff without worrying how much work it'll take in the end, or is it even possible.

Could the crankshaft mass, journal diameter and crank length (-> bore spacing) have more effect than flywheel and/or damper weights/diameters? Some straight six engines have horrible crank harmonics, that cause problems with oil pump gear's nut (BMW M54B30 atleast, fix is to use Ati super damper and...

My very optimistic target is to try achieve near 400hp (@ crank) naturally aspirated at some point, but also try how high the engine actually can be revved. Current target is to reach 300hp @ ~7000rpm (stock cams).. which shouldn't be a problem with more work, since the current results are already q...

36mm is the biggest intake valve, that is possible to fit (with larger seats). But I think 33mm is enough for quite high hp potential (and rpm). Bore is another restriction (valve shrouding), making larger intake valve worth less hp in my opinion. If the bore was something like 86-87mm, I would have...

Yes, they are adjustable independently and I've tried some slightly different timings. Pictures I found from my imgur account (minor changes done to engine, engine bay..mostly just 'cleaning' and added restrictive filters) https://i.imgur.com/DqgNcpj.jpg https://i.imgur.com/gRz30Qc.jpg Intake port (...

Yes, the cam followers are 32mm at diameter.
I'll go with the specs you recommended, and see how it'll work.
Thank you very much!

I've been working on my six cylinder Volvo B6304 N/A engine for quite a while now. Still running stock cams (about 208*@0.050" and ~9mm lift) - they are for hydraulic lifters, but I've converted them solid because I rev my engine up to 7500rpm. The valve clearances take away some lift and durat...